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-rw-r--r--kernel/trace/trace.c2261
1 files changed, 1601 insertions, 660 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index c2e2c2310374..ae6fa2d1cdf7 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1,7 +1,7 @@
/*
* ring buffer based function tracer
*
- * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
+ * Copyright (C) 2007-2012 Steven Rostedt <srostedt@redhat.com>
* Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
*
* Originally taken from the RT patch by:
@@ -19,7 +19,6 @@
#include <linux/seq_file.h>
#include <linux/notifier.h>
#include <linux/irqflags.h>
-#include <linux/irq_work.h>
#include <linux/debugfs.h>
#include <linux/pagemap.h>
#include <linux/hardirq.h>
@@ -48,7 +47,7 @@
* On boot up, the ring buffer is set to the minimum size, so that
* we do not waste memory on systems that are not using tracing.
*/
-int ring_buffer_expanded;
+bool ring_buffer_expanded;
/*
* We need to change this state when a selftest is running.
@@ -87,14 +86,6 @@ static int dummy_set_flag(u32 old_flags, u32 bit, int set)
static DEFINE_PER_CPU(bool, trace_cmdline_save);
/*
- * When a reader is waiting for data, then this variable is
- * set to true.
- */
-static bool trace_wakeup_needed;
-
-static struct irq_work trace_work_wakeup;
-
-/*
* Kill all tracing for good (never come back).
* It is initialized to 1 but will turn to zero if the initialization
* of the tracer is successful. But that is the only place that sets
@@ -130,12 +121,14 @@ static int tracing_set_tracer(const char *buf);
static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata;
static char *default_bootup_tracer;
+static bool allocate_snapshot;
+
static int __init set_cmdline_ftrace(char *str)
{
- strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE);
+ strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE);
default_bootup_tracer = bootup_tracer_buf;
/* We are using ftrace early, expand it */
- ring_buffer_expanded = 1;
+ ring_buffer_expanded = true;
return 1;
}
__setup("ftrace=", set_cmdline_ftrace);
@@ -156,13 +149,22 @@ static int __init set_ftrace_dump_on_oops(char *str)
}
__setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops);
+static int __init boot_alloc_snapshot(char *str)
+{
+ allocate_snapshot = true;
+ /* We also need the main ring buffer expanded */
+ ring_buffer_expanded = true;
+ return 1;
+}
+__setup("alloc_snapshot", boot_alloc_snapshot);
+
static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata;
static char *trace_boot_options __initdata;
static int __init set_trace_boot_options(char *str)
{
- strncpy(trace_boot_options_buf, str, MAX_TRACER_SIZE);
+ strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE);
trace_boot_options = trace_boot_options_buf;
return 0;
}
@@ -189,7 +191,7 @@ unsigned long long ns2usecs(cycle_t nsec)
*/
static struct trace_array global_trace;
-static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu);
+LIST_HEAD(ftrace_trace_arrays);
int filter_current_check_discard(struct ring_buffer *buffer,
struct ftrace_event_call *call, void *rec,
@@ -204,29 +206,15 @@ cycle_t ftrace_now(int cpu)
u64 ts;
/* Early boot up does not have a buffer yet */
- if (!global_trace.buffer)
+ if (!global_trace.trace_buffer.buffer)
return trace_clock_local();
- ts = ring_buffer_time_stamp(global_trace.buffer, cpu);
- ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts);
+ ts = ring_buffer_time_stamp(global_trace.trace_buffer.buffer, cpu);
+ ring_buffer_normalize_time_stamp(global_trace.trace_buffer.buffer, cpu, &ts);
return ts;
}
-/*
- * The max_tr is used to snapshot the global_trace when a maximum
- * latency is reached. Some tracers will use this to store a maximum
- * trace while it continues examining live traces.
- *
- * The buffers for the max_tr are set up the same as the global_trace.
- * When a snapshot is taken, the link list of the max_tr is swapped
- * with the link list of the global_trace and the buffers are reset for
- * the global_trace so the tracing can continue.
- */
-static struct trace_array max_tr;
-
-static DEFINE_PER_CPU(struct trace_array_cpu, max_tr_data);
-
int tracing_is_enabled(void)
{
return tracing_is_on();
@@ -249,9 +237,6 @@ static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT;
/* trace_types holds a link list of available tracers. */
static struct tracer *trace_types __read_mostly;
-/* current_trace points to the tracer that is currently active */
-static struct tracer *current_trace __read_mostly = &nop_trace;
-
/*
* trace_types_lock is used to protect the trace_types list.
*/
@@ -285,13 +270,13 @@ static DEFINE_PER_CPU(struct mutex, cpu_access_lock);
static inline void trace_access_lock(int cpu)
{
- if (cpu == TRACE_PIPE_ALL_CPU) {
+ if (cpu == RING_BUFFER_ALL_CPUS) {
/* gain it for accessing the whole ring buffer. */
down_write(&all_cpu_access_lock);
} else {
/* gain it for accessing a cpu ring buffer. */
- /* Firstly block other trace_access_lock(TRACE_PIPE_ALL_CPU). */
+ /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */
down_read(&all_cpu_access_lock);
/* Secondly block other access to this @cpu ring buffer. */
@@ -301,7 +286,7 @@ static inline void trace_access_lock(int cpu)
static inline void trace_access_unlock(int cpu)
{
- if (cpu == TRACE_PIPE_ALL_CPU) {
+ if (cpu == RING_BUFFER_ALL_CPUS) {
up_write(&all_cpu_access_lock);
} else {
mutex_unlock(&per_cpu(cpu_access_lock, cpu));
@@ -339,30 +324,11 @@ static inline void trace_access_lock_init(void)
#endif
-/* trace_wait is a waitqueue for tasks blocked on trace_poll */
-static DECLARE_WAIT_QUEUE_HEAD(trace_wait);
-
/* trace_flags holds trace_options default values */
unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK |
TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME |
TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE |
- TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS;
-
-static int trace_stop_count;
-static DEFINE_RAW_SPINLOCK(tracing_start_lock);
-
-/**
- * trace_wake_up - wake up tasks waiting for trace input
- *
- * Schedules a delayed work to wake up any task that is blocked on the
- * trace_wait queue. These is used with trace_poll for tasks polling the
- * trace.
- */
-static void trace_wake_up(struct irq_work *work)
-{
- wake_up_all(&trace_wait);
-
-}
+ TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | TRACE_ITER_FUNCTION;
/**
* tracing_on - enable tracing buffers
@@ -372,8 +338,8 @@ static void trace_wake_up(struct irq_work *work)
*/
void tracing_on(void)
{
- if (global_trace.buffer)
- ring_buffer_record_on(global_trace.buffer);
+ if (global_trace.trace_buffer.buffer)
+ ring_buffer_record_on(global_trace.trace_buffer.buffer);
/*
* This flag is only looked at when buffers haven't been
* allocated yet. We don't really care about the race
@@ -385,6 +351,196 @@ void tracing_on(void)
EXPORT_SYMBOL_GPL(tracing_on);
/**
+ * __trace_puts - write a constant string into the trace buffer.
+ * @ip: The address of the caller
+ * @str: The constant string to write
+ * @size: The size of the string.
+ */
+int __trace_puts(unsigned long ip, const char *str, int size)
+{
+ struct ring_buffer_event *event;
+ struct ring_buffer *buffer;
+ struct print_entry *entry;
+ unsigned long irq_flags;
+ int alloc;
+
+ alloc = sizeof(*entry) + size + 2; /* possible \n added */
+
+ local_save_flags(irq_flags);
+ buffer = global_trace.trace_buffer.buffer;
+ event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc,
+ irq_flags, preempt_count());
+ if (!event)
+ return 0;
+
+ entry = ring_buffer_event_data(event);
+ entry->ip = ip;
+
+ memcpy(&entry->buf, str, size);
+
+ /* Add a newline if necessary */
+ if (entry->buf[size - 1] != '\n') {
+ entry->buf[size] = '\n';
+ entry->buf[size + 1] = '\0';
+ } else
+ entry->buf[size] = '\0';
+
+ __buffer_unlock_commit(buffer, event);
+
+ return size;
+}
+EXPORT_SYMBOL_GPL(__trace_puts);
+
+/**
+ * __trace_bputs - write the pointer to a constant string into trace buffer
+ * @ip: The address of the caller
+ * @str: The constant string to write to the buffer to
+ */
+int __trace_bputs(unsigned long ip, const char *str)
+{
+ struct ring_buffer_event *event;
+ struct ring_buffer *buffer;
+ struct bputs_entry *entry;
+ unsigned long irq_flags;
+ int size = sizeof(struct bputs_entry);
+
+ local_save_flags(irq_flags);
+ buffer = global_trace.trace_buffer.buffer;
+ event = trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size,
+ irq_flags, preempt_count());
+ if (!event)
+ return 0;
+
+ entry = ring_buffer_event_data(event);
+ entry->ip = ip;
+ entry->str = str;
+
+ __buffer_unlock_commit(buffer, event);
+
+ return 1;
+}
+EXPORT_SYMBOL_GPL(__trace_bputs);
+
+#ifdef CONFIG_TRACER_SNAPSHOT
+/**
+ * trace_snapshot - take a snapshot of the current buffer.
+ *
+ * This causes a swap between the snapshot buffer and the current live
+ * tracing buffer. You can use this to take snapshots of the live
+ * trace when some condition is triggered, but continue to trace.
+ *
+ * Note, make sure to allocate the snapshot with either
+ * a tracing_snapshot_alloc(), or by doing it manually
+ * with: echo 1 > /sys/kernel/debug/tracing/snapshot
+ *
+ * If the snapshot buffer is not allocated, it will stop tracing.
+ * Basically making a permanent snapshot.
+ */
+void tracing_snapshot(void)
+{
+ struct trace_array *tr = &global_trace;
+ struct tracer *tracer = tr->current_trace;
+ unsigned long flags;
+
+ if (in_nmi()) {
+ internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n");
+ internal_trace_puts("*** snapshot is being ignored ***\n");
+ return;
+ }
+
+ if (!tr->allocated_snapshot) {
+ internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n");
+ internal_trace_puts("*** stopping trace here! ***\n");
+ tracing_off();
+ return;
+ }
+
+ /* Note, snapshot can not be used when the tracer uses it */
+ if (tracer->use_max_tr) {
+ internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n");
+ internal_trace_puts("*** Can not use snapshot (sorry) ***\n");
+ return;
+ }
+
+ local_irq_save(flags);
+ update_max_tr(tr, current, smp_processor_id());
+ local_irq_restore(flags);
+}
+EXPORT_SYMBOL_GPL(tracing_snapshot);
+
+static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf,
+ struct trace_buffer *size_buf, int cpu_id);
+static void set_buffer_entries(struct trace_buffer *buf, unsigned long val);
+
+static int alloc_snapshot(struct trace_array *tr)
+{
+ int ret;
+
+ if (!tr->allocated_snapshot) {
+
+ /* allocate spare buffer */
+ ret = resize_buffer_duplicate_size(&tr->max_buffer,
+ &tr->trace_buffer, RING_BUFFER_ALL_CPUS);
+ if (ret < 0)
+ return ret;
+
+ tr->allocated_snapshot = true;
+ }
+
+ return 0;
+}
+
+void free_snapshot(struct trace_array *tr)
+{
+ /*
+ * We don't free the ring buffer. instead, resize it because
+ * The max_tr ring buffer has some state (e.g. ring->clock) and
+ * we want preserve it.
+ */
+ ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS);
+ set_buffer_entries(&tr->max_buffer, 1);
+ tracing_reset_online_cpus(&tr->max_buffer);
+ tr->allocated_snapshot = false;
+}
+
+/**
+ * trace_snapshot_alloc - allocate and take a snapshot of the current buffer.
+ *
+ * This is similar to trace_snapshot(), but it will allocate the
+ * snapshot buffer if it isn't already allocated. Use this only
+ * where it is safe to sleep, as the allocation may sleep.
+ *
+ * This causes a swap between the snapshot buffer and the current live
+ * tracing buffer. You can use this to take snapshots of the live
+ * trace when some condition is triggered, but continue to trace.
+ */
+void tracing_snapshot_alloc(void)
+{
+ struct trace_array *tr = &global_trace;
+ int ret;
+
+ ret = alloc_snapshot(tr);
+ if (WARN_ON(ret < 0))
+ return;
+
+ tracing_snapshot();
+}
+EXPORT_SYMBOL_GPL(tracing_snapshot_alloc);
+#else
+void tracing_snapshot(void)
+{
+ WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used");
+}
+EXPORT_SYMBOL_GPL(tracing_snapshot);
+void tracing_snapshot_alloc(void)
+{
+ /* Give warning */
+ tracing_snapshot();
+}
+EXPORT_SYMBOL_GPL(tracing_snapshot_alloc);
+#endif /* CONFIG_TRACER_SNAPSHOT */
+
+/**
* tracing_off - turn off tracing buffers
*
* This function stops the tracing buffers from recording data.
@@ -394,8 +550,8 @@ EXPORT_SYMBOL_GPL(tracing_on);
*/
void tracing_off(void)
{
- if (global_trace.buffer)
- ring_buffer_record_off(global_trace.buffer);
+ if (global_trace.trace_buffer.buffer)
+ ring_buffer_record_off(global_trace.trace_buffer.buffer);
/*
* This flag is only looked at when buffers haven't been
* allocated yet. We don't really care about the race
@@ -411,8 +567,8 @@ EXPORT_SYMBOL_GPL(tracing_off);
*/
int tracing_is_on(void)
{
- if (global_trace.buffer)
- return ring_buffer_record_is_on(global_trace.buffer);
+ if (global_trace.trace_buffer.buffer)
+ return ring_buffer_record_is_on(global_trace.trace_buffer.buffer);
return !global_trace.buffer_disabled;
}
EXPORT_SYMBOL_GPL(tracing_is_on);
@@ -479,6 +635,7 @@ static const char *trace_options[] = {
"disable_on_free",
"irq-info",
"markers",
+ "function-trace",
NULL
};
@@ -490,6 +647,8 @@ static struct {
{ trace_clock_local, "local", 1 },
{ trace_clock_global, "global", 1 },
{ trace_clock_counter, "counter", 0 },
+ { trace_clock_jiffies, "uptime", 1 },
+ { trace_clock, "perf", 1 },
ARCH_TRACE_CLOCKS
};
@@ -670,13 +829,14 @@ unsigned long __read_mostly tracing_max_latency;
static void
__update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
{
- struct trace_array_cpu *data = tr->data[cpu];
- struct trace_array_cpu *max_data;
+ struct trace_buffer *trace_buf = &tr->trace_buffer;
+ struct trace_buffer *max_buf = &tr->max_buffer;
+ struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu);
+ struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu);
- max_tr.cpu = cpu;
- max_tr.time_start = data->preempt_timestamp;
+ max_buf->cpu = cpu;
+ max_buf->time_start = data->preempt_timestamp;
- max_data = max_tr.data[cpu];
max_data->saved_latency = tracing_max_latency;
max_data->critical_start = data->critical_start;
max_data->critical_end = data->critical_end;
@@ -704,23 +864,24 @@ __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
void
update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
{
- struct ring_buffer *buf = tr->buffer;
+ struct ring_buffer *buf;
- if (trace_stop_count)
+ if (tr->stop_count)
return;
WARN_ON_ONCE(!irqs_disabled());
- if (!current_trace->allocated_snapshot) {
+ if (!tr->allocated_snapshot) {
/* Only the nop tracer should hit this when disabling */
- WARN_ON_ONCE(current_trace != &nop_trace);
+ WARN_ON_ONCE(tr->current_trace != &nop_trace);
return;
}
arch_spin_lock(&ftrace_max_lock);
- tr->buffer = max_tr.buffer;
- max_tr.buffer = buf;
+ buf = tr->trace_buffer.buffer;
+ tr->trace_buffer.buffer = tr->max_buffer.buffer;
+ tr->max_buffer.buffer = buf;
__update_max_tr(tr, tsk, cpu);
arch_spin_unlock(&ftrace_max_lock);
@@ -739,16 +900,19 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
{
int ret;
- if (trace_stop_count)
+ if (tr->stop_count)
return;
WARN_ON_ONCE(!irqs_disabled());
- if (WARN_ON_ONCE(!current_trace->allocated_snapshot))
+ if (!tr->allocated_snapshot) {
+ /* Only the nop tracer should hit this when disabling */
+ WARN_ON_ONCE(tr->current_trace != &nop_trace);
return;
+ }
arch_spin_lock(&ftrace_max_lock);
- ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu);
+ ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu);
if (ret == -EBUSY) {
/*
@@ -757,7 +921,7 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
* the max trace buffer (no one writes directly to it)
* and flag that it failed.
*/
- trace_array_printk(&max_tr, _THIS_IP_,
+ trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_,
"Failed to swap buffers due to commit in progress\n");
}
@@ -770,37 +934,78 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
static void default_wait_pipe(struct trace_iterator *iter)
{
- DEFINE_WAIT(wait);
+ /* Iterators are static, they should be filled or empty */
+ if (trace_buffer_iter(iter, iter->cpu_file))
+ return;
- prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE);
+ ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file);
+}
+
+#ifdef CONFIG_FTRACE_STARTUP_TEST
+static int run_tracer_selftest(struct tracer *type)
+{
+ struct trace_array *tr = &global_trace;
+ struct tracer *saved_tracer = tr->current_trace;
+ int ret;
+
+ if (!type->selftest || tracing_selftest_disabled)
+ return 0;
/*
- * The events can happen in critical sections where
- * checking a work queue can cause deadlocks.
- * After adding a task to the queue, this flag is set
- * only to notify events to try to wake up the queue
- * using irq_work.
- *
- * We don't clear it even if the buffer is no longer
- * empty. The flag only causes the next event to run
- * irq_work to do the work queue wake up. The worse
- * that can happen if we race with !trace_empty() is that
- * an event will cause an irq_work to try to wake up
- * an empty queue.
- *
- * There's no reason to protect this flag either, as
- * the work queue and irq_work logic will do the necessary
- * synchronization for the wake ups. The only thing
- * that is necessary is that the wake up happens after
- * a task has been queued. It's OK for spurious wake ups.
+ * Run a selftest on this tracer.
+ * Here we reset the trace buffer, and set the current
+ * tracer to be this tracer. The tracer can then run some
+ * internal tracing to verify that everything is in order.
+ * If we fail, we do not register this tracer.
*/
- trace_wakeup_needed = true;
+ tracing_reset_online_cpus(&tr->trace_buffer);
- if (trace_empty(iter))
- schedule();
+ tr->current_trace = type;
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+ if (type->use_max_tr) {
+ /* If we expanded the buffers, make sure the max is expanded too */
+ if (ring_buffer_expanded)
+ ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size,
+ RING_BUFFER_ALL_CPUS);
+ tr->allocated_snapshot = true;
+ }
+#endif
- finish_wait(&trace_wait, &wait);
+ /* the test is responsible for initializing and enabling */
+ pr_info("Testing tracer %s: ", type->name);
+ ret = type->selftest(type, tr);
+ /* the test is responsible for resetting too */
+ tr->current_trace = saved_tracer;
+ if (ret) {
+ printk(KERN_CONT "FAILED!\n");
+ /* Add the warning after printing 'FAILED' */
+ WARN_ON(1);
+ return -1;
+ }
+ /* Only reset on passing, to avoid touching corrupted buffers */
+ tracing_reset_online_cpus(&tr->trace_buffer);
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+ if (type->use_max_tr) {
+ tr->allocated_snapshot = false;
+
+ /* Shrink the max buffer again */
+ if (ring_buffer_expanded)
+ ring_buffer_resize(tr->max_buffer.buffer, 1,
+ RING_BUFFER_ALL_CPUS);
+ }
+#endif
+
+ printk(KERN_CONT "PASSED\n");
+ return 0;
}
+#else
+static inline int run_tracer_selftest(struct tracer *type)
+{
+ return 0;
+}
+#endif /* CONFIG_FTRACE_STARTUP_TEST */
/**
* register_tracer - register a tracer with the ftrace system.
@@ -847,57 +1052,9 @@ int register_tracer(struct tracer *type)
if (!type->wait_pipe)
type->wait_pipe = default_wait_pipe;
-
-#ifdef CONFIG_FTRACE_STARTUP_TEST
- if (type->selftest && !tracing_selftest_disabled) {
- struct tracer *saved_tracer = current_trace;
- struct trace_array *tr = &global_trace;
-
- /*
- * Run a selftest on this tracer.
- * Here we reset the trace buffer, and set the current
- * tracer to be this tracer. The tracer can then run some
- * internal tracing to verify that everything is in order.
- * If we fail, we do not register this tracer.
- */
- tracing_reset_online_cpus(tr);
-
- current_trace = type;
-
- if (type->use_max_tr) {
- /* If we expanded the buffers, make sure the max is expanded too */
- if (ring_buffer_expanded)
- ring_buffer_resize(max_tr.buffer, trace_buf_size,
- RING_BUFFER_ALL_CPUS);
- type->allocated_snapshot = true;
- }
-
- /* the test is responsible for initializing and enabling */
- pr_info("Testing tracer %s: ", type->name);
- ret = type->selftest(type, tr);
- /* the test is responsible for resetting too */
- current_trace = saved_tracer;
- if (ret) {
- printk(KERN_CONT "FAILED!\n");
- /* Add the warning after printing 'FAILED' */
- WARN_ON(1);
- goto out;
- }
- /* Only reset on passing, to avoid touching corrupted buffers */
- tracing_reset_online_cpus(tr);
-
- if (type->use_max_tr) {
- type->allocated_snapshot = false;
-
- /* Shrink the max buffer again */
- if (ring_buffer_expanded)
- ring_buffer_resize(max_tr.buffer, 1,
- RING_BUFFER_ALL_CPUS);
- }
-
- printk(KERN_CONT "PASSED\n");
- }
-#endif
+ ret = run_tracer_selftest(type);
+ if (ret < 0)
+ goto out;
type->next = trace_types;
trace_types = type;
@@ -917,7 +1074,7 @@ int register_tracer(struct tracer *type)
tracing_set_tracer(type->name);
default_bootup_tracer = NULL;
/* disable other selftests, since this will break it. */
- tracing_selftest_disabled = 1;
+ tracing_selftest_disabled = true;
#ifdef CONFIG_FTRACE_STARTUP_TEST
printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n",
type->name);
@@ -927,9 +1084,9 @@ int register_tracer(struct tracer *type)
return ret;
}
-void tracing_reset(struct trace_array *tr, int cpu)
+void tracing_reset(struct trace_buffer *buf, int cpu)
{
- struct ring_buffer *buffer = tr->buffer;
+ struct ring_buffer *buffer = buf->buffer;
if (!buffer)
return;
@@ -943,9 +1100,9 @@ void tracing_reset(struct trace_array *tr, int cpu)
ring_buffer_record_enable(buffer);
}
-void tracing_reset_online_cpus(struct trace_array *tr)
+void tracing_reset_online_cpus(struct trace_buffer *buf)
{
- struct ring_buffer *buffer = tr->buffer;
+ struct ring_buffer *buffer = buf->buffer;
int cpu;
if (!buffer)
@@ -956,7 +1113,7 @@ void tracing_reset_online_cpus(struct trace_array *tr)
/* Make sure all commits have finished */
synchronize_sched();
- tr->time_start = ftrace_now(tr->cpu);
+ buf->time_start = ftrace_now(buf->cpu);
for_each_online_cpu(cpu)
ring_buffer_reset_cpu(buffer, cpu);
@@ -966,12 +1123,21 @@ void tracing_reset_online_cpus(struct trace_array *tr)
void tracing_reset_current(int cpu)
{
- tracing_reset(&global_trace, cpu);
+ tracing_reset(&global_trace.trace_buffer, cpu);
}
-void tracing_reset_current_online_cpus(void)
+void tracing_reset_all_online_cpus(void)
{
- tracing_reset_online_cpus(&global_trace);
+ struct trace_array *tr;
+
+ mutex_lock(&trace_types_lock);
+ list_for_each_entry(tr, &ftrace_trace_arrays, list) {
+ tracing_reset_online_cpus(&tr->trace_buffer);
+#ifdef CONFIG_TRACER_MAX_TRACE
+ tracing_reset_online_cpus(&tr->max_buffer);
+#endif
+ }
+ mutex_unlock(&trace_types_lock);
}
#define SAVED_CMDLINES 128
@@ -994,7 +1160,7 @@ static void trace_init_cmdlines(void)
int is_tracing_stopped(void)
{
- return trace_stop_count;
+ return global_trace.stop_count;
}
/**
@@ -1026,12 +1192,12 @@ void tracing_start(void)
if (tracing_disabled)
return;
- raw_spin_lock_irqsave(&tracing_start_lock, flags);
- if (--trace_stop_count) {
- if (trace_stop_count < 0) {
+ raw_spin_lock_irqsave(&global_trace.start_lock, flags);
+ if (--global_trace.stop_count) {
+ if (global_trace.stop_count < 0) {
/* Someone screwed up their debugging */
WARN_ON_ONCE(1);
- trace_stop_count = 0;
+ global_trace.stop_count = 0;
}
goto out;
}
@@ -1039,19 +1205,52 @@ void tracing_start(void)
/* Prevent the buffers from switching */
arch_spin_lock(&ftrace_max_lock);
- buffer = global_trace.buffer;
+ buffer = global_trace.trace_buffer.buffer;
if (buffer)
ring_buffer_record_enable(buffer);
- buffer = max_tr.buffer;
+#ifdef CONFIG_TRACER_MAX_TRACE
+ buffer = global_trace.max_buffer.buffer;
if (buffer)
ring_buffer_record_enable(buffer);
+#endif
arch_spin_unlock(&ftrace_max_lock);
ftrace_start();
out:
- raw_spin_unlock_irqrestore(&tracing_start_lock, flags);
+ raw_spin_unlock_irqrestore(&global_trace.start_lock, flags);
+}
+
+static void tracing_start_tr(struct trace_array *tr)
+{
+ struct ring_buffer *buffer;
+ unsigned long flags;
+
+ if (tracing_disabled)
+ return;
+
+ /* If global, we need to also start the max tracer */
+ if (tr->flags & TRACE_ARRAY_FL_GLOBAL)
+ return tracing_start();
+
+ raw_spin_lock_irqsave(&tr->start_lock, flags);
+
+ if (--tr->stop_count) {
+ if (tr->stop_count < 0) {
+ /* Someone screwed up their debugging */
+ WARN_ON_ONCE(1);
+ tr->stop_count = 0;
+ }
+ goto out;
+ }
+
+ buffer = tr->trace_buffer.buffer;
+ if (buffer)
+ ring_buffer_record_enable(buffer);
+
+ out:
+ raw_spin_unlock_irqrestore(&tr->start_lock, flags);
}
/**
@@ -1066,25 +1265,48 @@ void tracing_stop(void)
unsigned long flags;
ftrace_stop();
- raw_spin_lock_irqsave(&tracing_start_lock, flags);
- if (trace_stop_count++)
+ raw_spin_lock_irqsave(&global_trace.start_lock, flags);
+ if (global_trace.stop_count++)
goto out;
/* Prevent the buffers from switching */
arch_spin_lock(&ftrace_max_lock);
- buffer = global_trace.buffer;
+ buffer = global_trace.trace_buffer.buffer;
if (buffer)
ring_buffer_record_disable(buffer);
- buffer = max_tr.buffer;
+#ifdef CONFIG_TRACER_MAX_TRACE
+ buffer = global_trace.max_buffer.buffer;
if (buffer)
ring_buffer_record_disable(buffer);
+#endif
arch_spin_unlock(&ftrace_max_lock);
out:
- raw_spin_unlock_irqrestore(&tracing_start_lock, flags);
+ raw_spin_unlock_irqrestore(&global_trace.start_lock, flags);
+}
+
+static void tracing_stop_tr(struct trace_array *tr)
+{
+ struct ring_buffer *buffer;
+ unsigned long flags;
+
+ /* If global, we need to also stop the max tracer */
+ if (tr->flags & TRACE_ARRAY_FL_GLOBAL)
+ return tracing_stop();
+
+ raw_spin_lock_irqsave(&tr->start_lock, flags);
+ if (tr->stop_count++)
+ goto out;
+
+ buffer = tr->trace_buffer.buffer;
+ if (buffer)
+ ring_buffer_record_disable(buffer);
+
+ out:
+ raw_spin_unlock_irqrestore(&tr->start_lock, flags);
}
void trace_stop_cmdline_recording(void);
@@ -1217,11 +1439,6 @@ void
__buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event)
{
__this_cpu_write(trace_cmdline_save, true);
- if (trace_wakeup_needed) {
- trace_wakeup_needed = false;
- /* irq_work_queue() supplies it's own memory barriers */
- irq_work_queue(&trace_work_wakeup);
- }
ring_buffer_unlock_commit(buffer, event);
}
@@ -1245,11 +1462,23 @@ void trace_buffer_unlock_commit(struct ring_buffer *buffer,
EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit);
struct ring_buffer_event *
+trace_event_buffer_lock_reserve(struct ring_buffer **current_rb,
+ struct ftrace_event_file *ftrace_file,
+ int type, unsigned long len,
+ unsigned long flags, int pc)
+{
+ *current_rb = ftrace_file->tr->trace_buffer.buffer;
+ return trace_buffer_lock_reserve(*current_rb,
+ type, len, flags, pc);
+}
+EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve);
+
+struct ring_buffer_event *
trace_current_buffer_lock_reserve(struct ring_buffer **current_rb,
int type, unsigned long len,
unsigned long flags, int pc)
{
- *current_rb = global_trace.buffer;
+ *current_rb = global_trace.trace_buffer.buffer;
return trace_buffer_lock_reserve(*current_rb,
type, len, flags, pc);
}
@@ -1288,7 +1517,7 @@ trace_function(struct trace_array *tr,
int pc)
{
struct ftrace_event_call *call = &event_function;
- struct ring_buffer *buffer = tr->buffer;
+ struct ring_buffer *buffer = tr->trace_buffer.buffer;
struct ring_buffer_event *event;
struct ftrace_entry *entry;
@@ -1429,13 +1658,14 @@ void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
int pc)
{
- __ftrace_trace_stack(tr->buffer, flags, skip, pc, NULL);
+ __ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL);
}
/**
* trace_dump_stack - record a stack back trace in the trace buffer
+ * @skip: Number of functions to skip (helper handlers)
*/
-void trace_dump_stack(void)
+void trace_dump_stack(int skip)
{
unsigned long flags;
@@ -1444,8 +1674,13 @@ void trace_dump_stack(void)
local_save_flags(flags);
- /* skipping 3 traces, seems to get us at the caller of this function */
- __ftrace_trace_stack(global_trace.buffer, flags, 3, preempt_count(), NULL);
+ /*
+ * Skip 3 more, seems to get us at the caller of
+ * this function.
+ */
+ skip += 3;
+ __ftrace_trace_stack(global_trace.trace_buffer.buffer,
+ flags, skip, preempt_count(), NULL);
}
static DEFINE_PER_CPU(int, user_stack_count);
@@ -1615,7 +1850,7 @@ void trace_printk_init_buffers(void)
* directly here. If the global_trace.buffer is already
* allocated here, then this was called by module code.
*/
- if (global_trace.buffer)
+ if (global_trace.trace_buffer.buffer)
tracing_start_cmdline_record();
}
@@ -1675,7 +1910,7 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
local_save_flags(flags);
size = sizeof(*entry) + sizeof(u32) * len;
- buffer = tr->buffer;
+ buffer = tr->trace_buffer.buffer;
event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size,
flags, pc);
if (!event)
@@ -1698,27 +1933,12 @@ out:
}
EXPORT_SYMBOL_GPL(trace_vbprintk);
-int trace_array_printk(struct trace_array *tr,
- unsigned long ip, const char *fmt, ...)
-{
- int ret;
- va_list ap;
-
- if (!(trace_flags & TRACE_ITER_PRINTK))
- return 0;
-
- va_start(ap, fmt);
- ret = trace_array_vprintk(tr, ip, fmt, ap);
- va_end(ap);
- return ret;
-}
-
-int trace_array_vprintk(struct trace_array *tr,
- unsigned long ip, const char *fmt, va_list args)
+static int
+__trace_array_vprintk(struct ring_buffer *buffer,
+ unsigned long ip, const char *fmt, va_list args)
{
struct ftrace_event_call *call = &event_print;
struct ring_buffer_event *event;
- struct ring_buffer *buffer;
int len = 0, size, pc;
struct print_entry *entry;
unsigned long flags;
@@ -1746,7 +1966,6 @@ int trace_array_vprintk(struct trace_array *tr,
local_save_flags(flags);
size = sizeof(*entry) + len + 1;
- buffer = tr->buffer;
event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size,
flags, pc);
if (!event)
@@ -1767,6 +1986,42 @@ int trace_array_vprintk(struct trace_array *tr,
return len;
}
+int trace_array_vprintk(struct trace_array *tr,
+ unsigned long ip, const char *fmt, va_list args)
+{
+ return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args);
+}
+
+int trace_array_printk(struct trace_array *tr,
+ unsigned long ip, const char *fmt, ...)
+{
+ int ret;
+ va_list ap;
+
+ if (!(trace_flags & TRACE_ITER_PRINTK))
+ return 0;
+
+ va_start(ap, fmt);
+ ret = trace_array_vprintk(tr, ip, fmt, ap);
+ va_end(ap);
+ return ret;
+}
+
+int trace_array_printk_buf(struct ring_buffer *buffer,
+ unsigned long ip, const char *fmt, ...)
+{
+ int ret;
+ va_list ap;
+
+ if (!(trace_flags & TRACE_ITER_PRINTK))
+ return 0;
+
+ va_start(ap, fmt);
+ ret = __trace_array_vprintk(buffer, ip, fmt, ap);
+ va_end(ap);
+ return ret;
+}
+
int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
{
return trace_array_vprintk(&global_trace, ip, fmt, args);
@@ -1792,7 +2047,7 @@ peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts,
if (buf_iter)
event = ring_buffer_iter_peek(buf_iter, ts);
else
- event = ring_buffer_peek(iter->tr->buffer, cpu, ts,
+ event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts,
lost_events);
if (event) {
@@ -1807,7 +2062,7 @@ static struct trace_entry *
__find_next_entry(struct trace_iterator *iter, int *ent_cpu,
unsigned long *missing_events, u64 *ent_ts)
{
- struct ring_buffer *buffer = iter->tr->buffer;
+ struct ring_buffer *buffer = iter->trace_buffer->buffer;
struct trace_entry *ent, *next = NULL;
unsigned long lost_events = 0, next_lost = 0;
int cpu_file = iter->cpu_file;
@@ -1820,7 +2075,7 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu,
* If we are in a per_cpu trace file, don't bother by iterating over
* all cpu and peek directly.
*/
- if (cpu_file > TRACE_PIPE_ALL_CPU) {
+ if (cpu_file > RING_BUFFER_ALL_CPUS) {
if (ring_buffer_empty_cpu(buffer, cpu_file))
return NULL;
ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events);
@@ -1884,7 +2139,7 @@ void *trace_find_next_entry_inc(struct trace_iterator *iter)
static void trace_consume(struct trace_iterator *iter)
{
- ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts,
+ ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts,
&iter->lost_events);
}
@@ -1917,13 +2172,12 @@ static void *s_next(struct seq_file *m, void *v, loff_t *pos)
void tracing_iter_reset(struct trace_iterator *iter, int cpu)
{
- struct trace_array *tr = iter->tr;
struct ring_buffer_event *event;
struct ring_buffer_iter *buf_iter;
unsigned long entries = 0;
u64 ts;
- tr->data[cpu]->skipped_entries = 0;
+ per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0;
buf_iter = trace_buffer_iter(iter, cpu);
if (!buf_iter)
@@ -1937,13 +2191,13 @@ void tracing_iter_reset(struct trace_iterator *iter, int cpu)
* by the timestamp being before the start of the buffer.
*/
while ((event = ring_buffer_iter_peek(buf_iter, &ts))) {
- if (ts >= iter->tr->time_start)
+ if (ts >= iter->trace_buffer->time_start)
break;
entries++;
ring_buffer_read(buf_iter, NULL);
}
- tr->data[cpu]->skipped_entries = entries;
+ per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries;
}
/*
@@ -1953,6 +2207,7 @@ void tracing_iter_reset(struct trace_iterator *iter, int cpu)
static void *s_start(struct seq_file *m, loff_t *pos)
{
struct trace_iterator *iter = m->private;
+ struct trace_array *tr = iter->tr;
int cpu_file = iter->cpu_file;
void *p = NULL;
loff_t l = 0;
@@ -1965,12 +2220,14 @@ static void *s_start(struct seq_file *m, loff_t *pos)
* will point to the same string as current_trace->name.
*/
mutex_lock(&trace_types_lock);
- if (unlikely(current_trace && iter->trace->name != current_trace->name))
- *iter->trace = *current_trace;
+ if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name))
+ *iter->trace = *tr->current_trace;
mutex_unlock(&trace_types_lock);
+#ifdef CONFIG_TRACER_MAX_TRACE
if (iter->snapshot && iter->trace->use_max_tr)
return ERR_PTR(-EBUSY);
+#endif
if (!iter->snapshot)
atomic_inc(&trace_record_cmdline_disabled);
@@ -1980,7 +2237,7 @@ static void *s_start(struct seq_file *m, loff_t *pos)
iter->cpu = 0;
iter->idx = -1;
- if (cpu_file == TRACE_PIPE_ALL_CPU) {
+ if (cpu_file == RING_BUFFER_ALL_CPUS) {
for_each_tracing_cpu(cpu)
tracing_iter_reset(iter, cpu);
} else
@@ -2012,17 +2269,21 @@ static void s_stop(struct seq_file *m, void *p)
{
struct trace_iterator *iter = m->private;
+#ifdef CONFIG_TRACER_MAX_TRACE
if (iter->snapshot && iter->trace->use_max_tr)
return;
+#endif
if (!iter->snapshot)
atomic_dec(&trace_record_cmdline_disabled);
+
trace_access_unlock(iter->cpu_file);
trace_event_read_unlock();
}
static void
-get_total_entries(struct trace_array *tr, unsigned long *total, unsigned long *entries)
+get_total_entries(struct trace_buffer *buf,
+ unsigned long *total, unsigned long *entries)
{
unsigned long count;
int cpu;
@@ -2031,19 +2292,19 @@ get_total_entries(struct trace_array *tr, unsigned long *total, unsigned long *e
*entries = 0;
for_each_tracing_cpu(cpu) {
- count = ring_buffer_entries_cpu(tr->buffer, cpu);
+ count = ring_buffer_entries_cpu(buf->buffer, cpu);
/*
* If this buffer has skipped entries, then we hold all
* entries for the trace and we need to ignore the
* ones before the time stamp.
*/
- if (tr->data[cpu]->skipped_entries) {
- count -= tr->data[cpu]->skipped_entries;
+ if (per_cpu_ptr(buf->data, cpu)->skipped_entries) {
+ count -= per_cpu_ptr(buf->data, cpu)->skipped_entries;
/* total is the same as the entries */
*total += count;
} else
*total += count +
- ring_buffer_overrun_cpu(tr->buffer, cpu);
+ ring_buffer_overrun_cpu(buf->buffer, cpu);
*entries += count;
}
}
@@ -2060,27 +2321,27 @@ static void print_lat_help_header(struct seq_file *m)
seq_puts(m, "# \\ / ||||| \\ | / \n");
}
-static void print_event_info(struct trace_array *tr, struct seq_file *m)
+static void print_event_info(struct trace_buffer *buf, struct seq_file *m)
{
unsigned long total;
unsigned long entries;
- get_total_entries(tr, &total, &entries);
+ get_total_entries(buf, &total, &entries);
seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n",
entries, total, num_online_cpus());
seq_puts(m, "#\n");
}
-static void print_func_help_header(struct trace_array *tr, struct seq_file *m)
+static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m)
{
- print_event_info(tr, m);
+ print_event_info(buf, m);
seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n");
seq_puts(m, "# | | | | |\n");
}
-static void print_func_help_header_irq(struct trace_array *tr, struct seq_file *m)
+static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m)
{
- print_event_info(tr, m);
+ print_event_info(buf, m);
seq_puts(m, "# _-----=> irqs-off\n");
seq_puts(m, "# / _----=> need-resched\n");
seq_puts(m, "# | / _---=> hardirq/softirq\n");
@@ -2094,16 +2355,16 @@ void
print_trace_header(struct seq_file *m, struct trace_iterator *iter)
{
unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK);
- struct trace_array *tr = iter->tr;
- struct trace_array_cpu *data = tr->data[tr->cpu];
- struct tracer *type = current_trace;
+ struct trace_buffer *buf = iter->trace_buffer;
+ struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu);
+ struct tracer *type = iter->trace;
unsigned long entries;
unsigned long total;
const char *name = "preemption";
name = type->name;
- get_total_entries(tr, &total, &entries);
+ get_total_entries(buf, &total, &entries);
seq_printf(m, "# %s latency trace v1.1.5 on %s\n",
name, UTS_RELEASE);
@@ -2114,7 +2375,7 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter)
nsecs_to_usecs(data->saved_latency),
entries,
total,
- tr->cpu,
+ buf->cpu,
#if defined(CONFIG_PREEMPT_NONE)
"server",
#elif defined(CONFIG_PREEMPT_VOLUNTARY)
@@ -2165,7 +2426,7 @@ static void test_cpu_buff_start(struct trace_iterator *iter)
if (cpumask_test_cpu(iter->cpu, iter->started))
return;
- if (iter->tr->data[iter->cpu]->skipped_entries)
+ if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries)
return;
cpumask_set_cpu(iter->cpu, iter->started);
@@ -2288,14 +2549,14 @@ int trace_empty(struct trace_iterator *iter)
int cpu;
/* If we are looking at one CPU buffer, only check that one */
- if (iter->cpu_file != TRACE_PIPE_ALL_CPU) {
+ if (iter->cpu_file != RING_BUFFER_ALL_CPUS) {
cpu = iter->cpu_file;
buf_iter = trace_buffer_iter(iter, cpu);
if (buf_iter) {
if (!ring_buffer_iter_empty(buf_iter))
return 0;
} else {
- if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu))
+ if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu))
return 0;
}
return 1;
@@ -2307,7 +2568,7 @@ int trace_empty(struct trace_iterator *iter)
if (!ring_buffer_iter_empty(buf_iter))
return 0;
} else {
- if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu))
+ if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu))
return 0;
}
}
@@ -2331,6 +2592,11 @@ enum print_line_t print_trace_line(struct trace_iterator *iter)
return ret;
}
+ if (iter->ent->type == TRACE_BPUTS &&
+ trace_flags & TRACE_ITER_PRINTK &&
+ trace_flags & TRACE_ITER_PRINTK_MSGONLY)
+ return trace_print_bputs_msg_only(iter);
+
if (iter->ent->type == TRACE_BPRINT &&
trace_flags & TRACE_ITER_PRINTK &&
trace_flags & TRACE_ITER_PRINTK_MSGONLY)
@@ -2385,9 +2651,9 @@ void trace_default_header(struct seq_file *m)
} else {
if (!(trace_flags & TRACE_ITER_VERBOSE)) {
if (trace_flags & TRACE_ITER_IRQ_INFO)
- print_func_help_header_irq(iter->tr, m);
+ print_func_help_header_irq(iter->trace_buffer, m);
else
- print_func_help_header(iter->tr, m);
+ print_func_help_header(iter->trace_buffer, m);
}
}
}
@@ -2400,6 +2666,50 @@ static void test_ftrace_alive(struct seq_file *m)
seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n");
}
+#ifdef CONFIG_TRACER_MAX_TRACE
+static void show_snapshot_main_help(struct seq_file *m)
+{
+ seq_printf(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n");
+ seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n");
+ seq_printf(m, "# Takes a snapshot of the main buffer.\n");
+ seq_printf(m, "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate)\n");
+ seq_printf(m, "# (Doesn't have to be '2' works with any number that\n");
+ seq_printf(m, "# is not a '0' or '1')\n");
+}
+
+static void show_snapshot_percpu_help(struct seq_file *m)
+{
+ seq_printf(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n");
+#ifdef CONFIG_RING_BUFFER_ALLOW_SWAP
+ seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n");
+ seq_printf(m, "# Takes a snapshot of the main buffer for this cpu.\n");
+#else
+ seq_printf(m, "# echo 1 > snapshot : Not supported with this kernel.\n");
+ seq_printf(m, "# Must use main snapshot file to allocate.\n");
+#endif
+ seq_printf(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n");
+ seq_printf(m, "# (Doesn't have to be '2' works with any number that\n");
+ seq_printf(m, "# is not a '0' or '1')\n");
+}
+
+static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter)
+{
+ if (iter->tr->allocated_snapshot)
+ seq_printf(m, "#\n# * Snapshot is allocated *\n#\n");
+ else
+ seq_printf(m, "#\n# * Snapshot is freed *\n#\n");
+
+ seq_printf(m, "# Snapshot commands:\n");
+ if (iter->cpu_file == RING_BUFFER_ALL_CPUS)
+ show_snapshot_main_help(m);
+ else
+ show_snapshot_percpu_help(m);
+}
+#else
+/* Should never be called */
+static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { }
+#endif
+
static int s_show(struct seq_file *m, void *v)
{
struct trace_iterator *iter = v;
@@ -2411,7 +2721,9 @@ static int s_show(struct seq_file *m, void *v)
seq_puts(m, "#\n");
test_ftrace_alive(m);
}
- if (iter->trace && iter->trace->print_header)
+ if (iter->snapshot && trace_empty(iter))
+ print_snapshot_help(m, iter);
+ else if (iter->trace && iter->trace->print_header)
iter->trace->print_header(m);
else
trace_default_header(m);
@@ -2452,7 +2764,8 @@ static const struct seq_operations tracer_seq_ops = {
static struct trace_iterator *
__tracing_open(struct inode *inode, struct file *file, bool snapshot)
{
- long cpu_file = (long) inode->i_private;
+ struct trace_cpu *tc = inode->i_private;
+ struct trace_array *tr = tc->tr;
struct trace_iterator *iter;
int cpu;
@@ -2477,26 +2790,31 @@ __tracing_open(struct inode *inode, struct file *file, bool snapshot)
if (!iter->trace)
goto fail;
- *iter->trace = *current_trace;
+ *iter->trace = *tr->current_trace;
if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL))
goto fail;
- if (current_trace->print_max || snapshot)
- iter->tr = &max_tr;
+ iter->tr = tr;
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+ /* Currently only the top directory has a snapshot */
+ if (tr->current_trace->print_max || snapshot)
+ iter->trace_buffer = &tr->max_buffer;
else
- iter->tr = &global_trace;
+#endif
+ iter->trace_buffer = &tr->trace_buffer;
iter->snapshot = snapshot;
iter->pos = -1;
mutex_init(&iter->mutex);
- iter->cpu_file = cpu_file;
+ iter->cpu_file = tc->cpu;
/* Notify the tracer early; before we stop tracing. */
if (iter->trace && iter->trace->open)
iter->trace->open(iter);
/* Annotate start of buffers if we had overruns */
- if (ring_buffer_overruns(iter->tr->buffer))
+ if (ring_buffer_overruns(iter->trace_buffer->buffer))
iter->iter_flags |= TRACE_FILE_ANNOTATE;
/* Output in nanoseconds only if we are using a clock in nanoseconds. */
@@ -2505,12 +2823,12 @@ __tracing_open(struct inode *inode, struct file *file, bool snapshot)
/* stop the trace while dumping if we are not opening "snapshot" */
if (!iter->snapshot)
- tracing_stop();
+ tracing_stop_tr(tr);
- if (iter->cpu_file == TRACE_PIPE_ALL_CPU) {
+ if (iter->cpu_file == RING_BUFFER_ALL_CPUS) {
for_each_tracing_cpu(cpu) {
iter->buffer_iter[cpu] =
- ring_buffer_read_prepare(iter->tr->buffer, cpu);
+ ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu);
}
ring_buffer_read_prepare_sync();
for_each_tracing_cpu(cpu) {
@@ -2520,12 +2838,14 @@ __tracing_open(struct inode *inode, struct file *file, bool snapshot)
} else {
cpu = iter->cpu_file;
iter->buffer_iter[cpu] =
- ring_buffer_read_prepare(iter->tr->buffer, cpu);
+ ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu);
ring_buffer_read_prepare_sync();
ring_buffer_read_start(iter->buffer_iter[cpu]);
tracing_iter_reset(iter, cpu);
}
+ tr->ref++;
+
mutex_unlock(&trace_types_lock);
return iter;
@@ -2552,14 +2872,20 @@ static int tracing_release(struct inode *inode, struct file *file)
{
struct seq_file *m = file->private_data;
struct trace_iterator *iter;
+ struct trace_array *tr;
int cpu;
if (!(file->f_mode & FMODE_READ))
return 0;
iter = m->private;
+ tr = iter->tr;
mutex_lock(&trace_types_lock);
+
+ WARN_ON(!tr->ref);
+ tr->ref--;
+
for_each_tracing_cpu(cpu) {
if (iter->buffer_iter[cpu])
ring_buffer_read_finish(iter->buffer_iter[cpu]);
@@ -2570,7 +2896,7 @@ static int tracing_release(struct inode *inode, struct file *file)
if (!iter->snapshot)
/* reenable tracing if it was previously enabled */
- tracing_start();
+ tracing_start_tr(tr);
mutex_unlock(&trace_types_lock);
mutex_destroy(&iter->mutex);
@@ -2589,12 +2915,13 @@ static int tracing_open(struct inode *inode, struct file *file)
/* If this file was open for write, then erase contents */
if ((file->f_mode & FMODE_WRITE) &&
(file->f_flags & O_TRUNC)) {
- long cpu = (long) inode->i_private;
+ struct trace_cpu *tc = inode->i_private;
+ struct trace_array *tr = tc->tr;
- if (cpu == TRACE_PIPE_ALL_CPU)
- tracing_reset_online_cpus(&global_trace);
+ if (tc->cpu == RING_BUFFER_ALL_CPUS)
+ tracing_reset_online_cpus(&tr->trace_buffer);
else
- tracing_reset(&global_trace, cpu);
+ tracing_reset(&tr->trace_buffer, tc->cpu);
}
if (file->f_mode & FMODE_READ) {
@@ -2741,8 +3068,9 @@ static ssize_t
tracing_cpumask_write(struct file *filp, const char __user *ubuf,
size_t count, loff_t *ppos)
{
- int err, cpu;
+ struct trace_array *tr = filp->private_data;
cpumask_var_t tracing_cpumask_new;
+ int err, cpu;
if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL))
return -ENOMEM;
@@ -2762,13 +3090,13 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
*/
if (cpumask_test_cpu(cpu, tracing_cpumask) &&
!cpumask_test_cpu(cpu, tracing_cpumask_new)) {
- atomic_inc(&global_trace.data[cpu]->disabled);
- ring_buffer_record_disable_cpu(global_trace.buffer, cpu);
+ atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled);
+ ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu);
}
if (!cpumask_test_cpu(cpu, tracing_cpumask) &&
cpumask_test_cpu(cpu, tracing_cpumask_new)) {
- atomic_dec(&global_trace.data[cpu]->disabled);
- ring_buffer_record_enable_cpu(global_trace.buffer, cpu);
+ atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled);
+ ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu);
}
}
arch_spin_unlock(&ftrace_max_lock);
@@ -2797,12 +3125,13 @@ static const struct file_operations tracing_cpumask_fops = {
static int tracing_trace_options_show(struct seq_file *m, void *v)
{
struct tracer_opt *trace_opts;
+ struct trace_array *tr = m->private;
u32 tracer_flags;
int i;
mutex_lock(&trace_types_lock);
- tracer_flags = current_trace->flags->val;
- trace_opts = current_trace->flags->opts;
+ tracer_flags = tr->current_trace->flags->val;
+ trace_opts = tr->current_trace->flags->opts;
for (i = 0; trace_options[i]; i++) {
if (trace_flags & (1 << i))
@@ -2857,11 +3186,25 @@ static int set_tracer_option(struct tracer *trace, char *cmp, int neg)
return -EINVAL;
}
-static void set_tracer_flags(unsigned int mask, int enabled)
+/* Some tracers require overwrite to stay enabled */
+int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set)
+{
+ if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set)
+ return -1;
+
+ return 0;
+}
+
+int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled)
{
/* do nothing if flag is already set */
if (!!(trace_flags & mask) == !!enabled)
- return;
+ return 0;
+
+ /* Give the tracer a chance to approve the change */
+ if (tr->current_trace->flag_changed)
+ if (tr->current_trace->flag_changed(tr->current_trace, mask, !!enabled))
+ return -EINVAL;
if (enabled)
trace_flags |= mask;
@@ -2871,18 +3214,24 @@ static void set_tracer_flags(unsigned int mask, int enabled)
if (mask == TRACE_ITER_RECORD_CMD)
trace_event_enable_cmd_record(enabled);
- if (mask == TRACE_ITER_OVERWRITE)
- ring_buffer_change_overwrite(global_trace.buffer, enabled);
+ if (mask == TRACE_ITER_OVERWRITE) {
+ ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled);
+#ifdef CONFIG_TRACER_MAX_TRACE
+ ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled);
+#endif
+ }
if (mask == TRACE_ITER_PRINTK)
trace_printk_start_stop_comm(enabled);
+
+ return 0;
}
-static int trace_set_options(char *option)
+static int trace_set_options(struct trace_array *tr, char *option)
{
char *cmp;
int neg = 0;
- int ret = 0;
+ int ret = -ENODEV;
int i;
cmp = strstrip(option);
@@ -2892,19 +3241,20 @@ static int trace_set_options(char *option)
cmp += 2;
}
+ mutex_lock(&trace_types_lock);
+
for (i = 0; trace_options[i]; i++) {
if (strcmp(cmp, trace_options[i]) == 0) {
- set_tracer_flags(1 << i, !neg);
+ ret = set_tracer_flag(tr, 1 << i, !neg);
break;
}
}
/* If no option could be set, test the specific tracer options */
- if (!trace_options[i]) {
- mutex_lock(&trace_types_lock);
- ret = set_tracer_option(current_trace, cmp, neg);
- mutex_unlock(&trace_types_lock);
- }
+ if (!trace_options[i])
+ ret = set_tracer_option(tr->current_trace, cmp, neg);
+
+ mutex_unlock(&trace_types_lock);
return ret;
}
@@ -2913,7 +3263,10 @@ static ssize_t
tracing_trace_options_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
+ struct seq_file *m = filp->private_data;
+ struct trace_array *tr = m->private;
char buf[64];
+ int ret;
if (cnt >= sizeof(buf))
return -EINVAL;
@@ -2923,7 +3276,9 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf,
buf[cnt] = 0;
- trace_set_options(buf);
+ ret = trace_set_options(tr, buf);
+ if (ret < 0)
+ return ret;
*ppos += cnt;
@@ -2934,7 +3289,8 @@ static int tracing_trace_options_open(struct inode *inode, struct file *file)
{
if (tracing_disabled)
return -ENODEV;
- return single_open(file, tracing_trace_options_show, NULL);
+
+ return single_open(file, tracing_trace_options_show, inode->i_private);
}
static const struct file_operations tracing_iter_fops = {
@@ -2947,20 +3303,84 @@ static const struct file_operations tracing_iter_fops = {
static const char readme_msg[] =
"tracing mini-HOWTO:\n\n"
- "# mount -t debugfs nodev /sys/kernel/debug\n\n"
- "# cat /sys/kernel/debug/tracing/available_tracers\n"
- "wakeup wakeup_rt preemptirqsoff preemptoff irqsoff function nop\n\n"
- "# cat /sys/kernel/debug/tracing/current_tracer\n"
- "nop\n"
- "# echo wakeup > /sys/kernel/debug/tracing/current_tracer\n"
- "# cat /sys/kernel/debug/tracing/current_tracer\n"
- "wakeup\n"
- "# cat /sys/kernel/debug/tracing/trace_options\n"
- "noprint-parent nosym-offset nosym-addr noverbose\n"
- "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n"
- "# echo 1 > /sys/kernel/debug/tracing/tracing_on\n"
- "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n"
- "# echo 0 > /sys/kernel/debug/tracing/tracing_on\n"
+ "# echo 0 > tracing_on : quick way to disable tracing\n"
+ "# echo 1 > tracing_on : quick way to re-enable tracing\n\n"
+ " Important files:\n"
+ " trace\t\t\t- The static contents of the buffer\n"
+ "\t\t\t To clear the buffer write into this file: echo > trace\n"
+ " trace_pipe\t\t- A consuming read to see the contents of the buffer\n"
+ " current_tracer\t- function and latency tracers\n"
+ " available_tracers\t- list of configured tracers for current_tracer\n"
+ " buffer_size_kb\t- view and modify size of per cpu buffer\n"
+ " buffer_total_size_kb - view total size of all cpu buffers\n\n"
+ " trace_clock\t\t-change the clock used to order events\n"
+ " local: Per cpu clock but may not be synced across CPUs\n"
+ " global: Synced across CPUs but slows tracing down.\n"
+ " counter: Not a clock, but just an increment\n"
+ " uptime: Jiffy counter from time of boot\n"
+ " perf: Same clock that perf events use\n"
+#ifdef CONFIG_X86_64
+ " x86-tsc: TSC cycle counter\n"
+#endif
+ "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n"
+ " tracing_cpumask\t- Limit which CPUs to trace\n"
+ " instances\t\t- Make sub-buffers with: mkdir instances/foo\n"
+ "\t\t\t Remove sub-buffer with rmdir\n"
+ " trace_options\t\t- Set format or modify how tracing happens\n"
+ "\t\t\t Disable an option by adding a suffix 'no' to the option name\n"
+#ifdef CONFIG_DYNAMIC_FTRACE
+ "\n available_filter_functions - list of functions that can be filtered on\n"
+ " set_ftrace_filter\t- echo function name in here to only trace these functions\n"
+ " accepts: func_full_name, *func_end, func_begin*, *func_middle*\n"
+ " modules: Can select a group via module\n"
+ " Format: :mod:<module-name>\n"
+ " example: echo :mod:ext3 > set_ftrace_filter\n"
+ " triggers: a command to perform when function is hit\n"
+ " Format: <function>:<trigger>[:count]\n"
+ " trigger: traceon, traceoff\n"
+ " enable_event:<system>:<event>\n"
+ " disable_event:<system>:<event>\n"
+#ifdef CONFIG_STACKTRACE
+ " stacktrace\n"
+#endif
+#ifdef CONFIG_TRACER_SNAPSHOT
+ " snapshot\n"
+#endif
+ " example: echo do_fault:traceoff > set_ftrace_filter\n"
+ " echo do_trap:traceoff:3 > set_ftrace_filter\n"
+ " The first one will disable tracing every time do_fault is hit\n"
+ " The second will disable tracing at most 3 times when do_trap is hit\n"
+ " The first time do trap is hit and it disables tracing, the counter\n"
+ " will decrement to 2. If tracing is already disabled, the counter\n"
+ " will not decrement. It only decrements when the trigger did work\n"
+ " To remove trigger without count:\n"
+ " echo '!<function>:<trigger> > set_ftrace_filter\n"
+ " To remove trigger with a count:\n"
+ " echo '!<function>:<trigger>:0 > set_ftrace_filter\n"
+ " set_ftrace_notrace\t- echo function name in here to never trace.\n"
+ " accepts: func_full_name, *func_end, func_begin*, *func_middle*\n"
+ " modules: Can select a group via module command :mod:\n"
+ " Does not accept triggers\n"
+#endif /* CONFIG_DYNAMIC_FTRACE */
+#ifdef CONFIG_FUNCTION_TRACER
+ " set_ftrace_pid\t- Write pid(s) to only function trace those pids (function)\n"
+#endif
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ " set_graph_function\t- Trace the nested calls of a function (function_graph)\n"
+ " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n"
+#endif
+#ifdef CONFIG_TRACER_SNAPSHOT
+ "\n snapshot\t\t- Like 'trace' but shows the content of the static snapshot buffer\n"
+ "\t\t\t Read the contents for more information\n"
+#endif
+#ifdef CONFIG_STACKTRACE
+ " stack_trace\t\t- Shows the max stack trace when active\n"
+ " stack_max_size\t- Shows current max stack size that was traced\n"
+ "\t\t\t Write into this file to reset the max size (trigger a new trace)\n"
+#ifdef CONFIG_DYNAMIC_FTRACE
+ " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace traces\n"
+#endif
+#endif /* CONFIG_STACKTRACE */
;
static ssize_t
@@ -3032,11 +3452,12 @@ static ssize_t
tracing_set_trace_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
+ struct trace_array *tr = filp->private_data;
char buf[MAX_TRACER_SIZE+2];
int r;
mutex_lock(&trace_types_lock);
- r = sprintf(buf, "%s\n", current_trace->name);
+ r = sprintf(buf, "%s\n", tr->current_trace->name);
mutex_unlock(&trace_types_lock);
return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
@@ -3044,43 +3465,48 @@ tracing_set_trace_read(struct file *filp, char __user *ubuf,
int tracer_init(struct tracer *t, struct trace_array *tr)
{
- tracing_reset_online_cpus(tr);
+ tracing_reset_online_cpus(&tr->trace_buffer);
return t->init(tr);
}
-static void set_buffer_entries(struct trace_array *tr, unsigned long val)
+static void set_buffer_entries(struct trace_buffer *buf, unsigned long val)
{
int cpu;
+
for_each_tracing_cpu(cpu)
- tr->data[cpu]->entries = val;
+ per_cpu_ptr(buf->data, cpu)->entries = val;
}
+#ifdef CONFIG_TRACER_MAX_TRACE
/* resize @tr's buffer to the size of @size_tr's entries */
-static int resize_buffer_duplicate_size(struct trace_array *tr,
- struct trace_array *size_tr, int cpu_id)
+static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf,
+ struct trace_buffer *size_buf, int cpu_id)
{
int cpu, ret = 0;
if (cpu_id == RING_BUFFER_ALL_CPUS) {
for_each_tracing_cpu(cpu) {
- ret = ring_buffer_resize(tr->buffer,
- size_tr->data[cpu]->entries, cpu);
+ ret = ring_buffer_resize(trace_buf->buffer,
+ per_cpu_ptr(size_buf->data, cpu)->entries, cpu);
if (ret < 0)
break;
- tr->data[cpu]->entries = size_tr->data[cpu]->entries;
+ per_cpu_ptr(trace_buf->data, cpu)->entries =
+ per_cpu_ptr(size_buf->data, cpu)->entries;
}
} else {
- ret = ring_buffer_resize(tr->buffer,
- size_tr->data[cpu_id]->entries, cpu_id);
+ ret = ring_buffer_resize(trace_buf->buffer,
+ per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id);
if (ret == 0)
- tr->data[cpu_id]->entries =
- size_tr->data[cpu_id]->entries;
+ per_cpu_ptr(trace_buf->data, cpu_id)->entries =
+ per_cpu_ptr(size_buf->data, cpu_id)->entries;
}
return ret;
}
+#endif /* CONFIG_TRACER_MAX_TRACE */
-static int __tracing_resize_ring_buffer(unsigned long size, int cpu)
+static int __tracing_resize_ring_buffer(struct trace_array *tr,
+ unsigned long size, int cpu)
{
int ret;
@@ -3089,23 +3515,25 @@ static int __tracing_resize_ring_buffer(unsigned long size, int cpu)
* we use the size that was given, and we can forget about
* expanding it later.
*/
- ring_buffer_expanded = 1;
+ ring_buffer_expanded = true;
/* May be called before buffers are initialized */
- if (!global_trace.buffer)
+ if (!tr->trace_buffer.buffer)
return 0;
- ret = ring_buffer_resize(global_trace.buffer, size, cpu);
+ ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu);
if (ret < 0)
return ret;
- if (!current_trace->use_max_tr)
+#ifdef CONFIG_TRACER_MAX_TRACE
+ if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) ||
+ !tr->current_trace->use_max_tr)
goto out;
- ret = ring_buffer_resize(max_tr.buffer, size, cpu);
+ ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu);
if (ret < 0) {
- int r = resize_buffer_duplicate_size(&global_trace,
- &global_trace, cpu);
+ int r = resize_buffer_duplicate_size(&tr->trace_buffer,
+ &tr->trace_buffer, cpu);
if (r < 0) {
/*
* AARGH! We are left with different
@@ -3128,20 +3556,23 @@ static int __tracing_resize_ring_buffer(unsigned long size, int cpu)
}
if (cpu == RING_BUFFER_ALL_CPUS)
- set_buffer_entries(&max_tr, size);
+ set_buffer_entries(&tr->max_buffer, size);
else
- max_tr.data[cpu]->entries = size;
+ per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size;
out:
+#endif /* CONFIG_TRACER_MAX_TRACE */
+
if (cpu == RING_BUFFER_ALL_CPUS)
- set_buffer_entries(&global_trace, size);
+ set_buffer_entries(&tr->trace_buffer, size);
else
- global_trace.data[cpu]->entries = size;
+ per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size;
return ret;
}
-static ssize_t tracing_resize_ring_buffer(unsigned long size, int cpu_id)
+static ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
+ unsigned long size, int cpu_id)
{
int ret = size;
@@ -3155,7 +3586,7 @@ static ssize_t tracing_resize_ring_buffer(unsigned long size, int cpu_id)
}
}
- ret = __tracing_resize_ring_buffer(size, cpu_id);
+ ret = __tracing_resize_ring_buffer(tr, size, cpu_id);
if (ret < 0)
ret = -ENOMEM;
@@ -3182,7 +3613,7 @@ int tracing_update_buffers(void)
mutex_lock(&trace_types_lock);
if (!ring_buffer_expanded)
- ret = __tracing_resize_ring_buffer(trace_buf_size,
+ ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size,
RING_BUFFER_ALL_CPUS);
mutex_unlock(&trace_types_lock);
@@ -3192,7 +3623,7 @@ int tracing_update_buffers(void)
struct trace_option_dentry;
static struct trace_option_dentry *
-create_trace_option_files(struct tracer *tracer);
+create_trace_option_files(struct trace_array *tr, struct tracer *tracer);
static void
destroy_trace_option_files(struct trace_option_dentry *topts);
@@ -3202,13 +3633,15 @@ static int tracing_set_tracer(const char *buf)
static struct trace_option_dentry *topts;
struct trace_array *tr = &global_trace;
struct tracer *t;
+#ifdef CONFIG_TRACER_MAX_TRACE
bool had_max_tr;
+#endif
int ret = 0;
mutex_lock(&trace_types_lock);
if (!ring_buffer_expanded) {
- ret = __tracing_resize_ring_buffer(trace_buf_size,
+ ret = __tracing_resize_ring_buffer(tr, trace_buf_size,
RING_BUFFER_ALL_CPUS);
if (ret < 0)
goto out;
@@ -3223,15 +3656,21 @@ static int tracing_set_tracer(const char *buf)
ret = -EINVAL;
goto out;
}
- if (t == current_trace)
+ if (t == tr->current_trace)
goto out;
trace_branch_disable();
- if (current_trace->reset)
- current_trace->reset(tr);
- had_max_tr = current_trace->allocated_snapshot;
- current_trace = &nop_trace;
+ tr->current_trace->enabled = false;
+
+ if (tr->current_trace->reset)
+ tr->current_trace->reset(tr);
+
+ /* Current trace needs to be nop_trace before synchronize_sched */
+ tr->current_trace = &nop_trace;
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+ had_max_tr = tr->allocated_snapshot;
if (had_max_tr && !t->use_max_tr) {
/*
@@ -3242,27 +3681,20 @@ static int tracing_set_tracer(const char *buf)
* so a synchronized_sched() is sufficient.
*/
synchronize_sched();
- /*
- * We don't free the ring buffer. instead, resize it because
- * The max_tr ring buffer has some state (e.g. ring->clock) and
- * we want preserve it.
- */
- ring_buffer_resize(max_tr.buffer, 1, RING_BUFFER_ALL_CPUS);
- set_buffer_entries(&max_tr, 1);
- tracing_reset_online_cpus(&max_tr);
- current_trace->allocated_snapshot = false;
+ free_snapshot(tr);
}
+#endif
destroy_trace_option_files(topts);
- topts = create_trace_option_files(t);
+ topts = create_trace_option_files(tr, t);
+
+#ifdef CONFIG_TRACER_MAX_TRACE
if (t->use_max_tr && !had_max_tr) {
- /* we need to make per cpu buffer sizes equivalent */
- ret = resize_buffer_duplicate_size(&max_tr, &global_trace,
- RING_BUFFER_ALL_CPUS);
+ ret = alloc_snapshot(tr);
if (ret < 0)
goto out;
- t->allocated_snapshot = true;
}
+#endif
if (t->init) {
ret = tracer_init(t, tr);
@@ -3270,7 +3702,8 @@ static int tracing_set_tracer(const char *buf)
goto out;
}
- current_trace = t;
+ tr->current_trace = t;
+ tr->current_trace->enabled = true;
trace_branch_enable(tr);
out:
mutex_unlock(&trace_types_lock);
@@ -3344,7 +3777,8 @@ tracing_max_lat_write(struct file *filp, const char __user *ubuf,
static int tracing_open_pipe(struct inode *inode, struct file *filp)
{
- long cpu_file = (long) inode->i_private;
+ struct trace_cpu *tc = inode->i_private;
+ struct trace_array *tr = tc->tr;
struct trace_iterator *iter;
int ret = 0;
@@ -3369,7 +3803,7 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp)
ret = -ENOMEM;
goto fail;
}
- *iter->trace = *current_trace;
+ *iter->trace = *tr->current_trace;
if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) {
ret = -ENOMEM;
@@ -3386,8 +3820,9 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp)
if (trace_clocks[trace_clock_id].in_ns)
iter->iter_flags |= TRACE_FILE_TIME_IN_NS;
- iter->cpu_file = cpu_file;
- iter->tr = &global_trace;
+ iter->cpu_file = tc->cpu;
+ iter->tr = tc->tr;
+ iter->trace_buffer = &tc->tr->trace_buffer;
mutex_init(&iter->mutex);
filp->private_data = iter;
@@ -3426,24 +3861,28 @@ static int tracing_release_pipe(struct inode *inode, struct file *file)
}
static unsigned int
-tracing_poll_pipe(struct file *filp, poll_table *poll_table)
+trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table)
{
- struct trace_iterator *iter = filp->private_data;
+ /* Iterators are static, they should be filled or empty */
+ if (trace_buffer_iter(iter, iter->cpu_file))
+ return POLLIN | POLLRDNORM;
- if (trace_flags & TRACE_ITER_BLOCK) {
+ if (trace_flags & TRACE_ITER_BLOCK)
/*
* Always select as readable when in blocking mode
*/
return POLLIN | POLLRDNORM;
- } else {
- if (!trace_empty(iter))
- return POLLIN | POLLRDNORM;
- poll_wait(filp, &trace_wait, poll_table);
- if (!trace_empty(iter))
- return POLLIN | POLLRDNORM;
+ else
+ return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file,
+ filp, poll_table);
+}
- return 0;
- }
+static unsigned int
+tracing_poll_pipe(struct file *filp, poll_table *poll_table)
+{
+ struct trace_iterator *iter = filp->private_data;
+
+ return trace_poll(iter, filp, poll_table);
}
/*
@@ -3509,6 +3948,7 @@ tracing_read_pipe(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
struct trace_iterator *iter = filp->private_data;
+ struct trace_array *tr = iter->tr;
ssize_t sret;
/* return any leftover data */
@@ -3520,8 +3960,8 @@ tracing_read_pipe(struct file *filp, char __user *ubuf,
/* copy the tracer to avoid using a global lock all around */
mutex_lock(&trace_types_lock);
- if (unlikely(iter->trace->name != current_trace->name))
- *iter->trace = *current_trace;
+ if (unlikely(iter->trace->name != tr->current_trace->name))
+ *iter->trace = *tr->current_trace;
mutex_unlock(&trace_types_lock);
/*
@@ -3677,6 +4117,7 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
.ops = &tracing_pipe_buf_ops,
.spd_release = tracing_spd_release_pipe,
};
+ struct trace_array *tr = iter->tr;
ssize_t ret;
size_t rem;
unsigned int i;
@@ -3686,8 +4127,8 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
/* copy the tracer to avoid using a global lock all around */
mutex_lock(&trace_types_lock);
- if (unlikely(iter->trace->name != current_trace->name))
- *iter->trace = *current_trace;
+ if (unlikely(iter->trace->name != tr->current_trace->name))
+ *iter->trace = *tr->current_trace;
mutex_unlock(&trace_types_lock);
mutex_lock(&iter->mutex);
@@ -3749,43 +4190,19 @@ out_err:
goto out;
}
-struct ftrace_entries_info {
- struct trace_array *tr;
- int cpu;
-};
-
-static int tracing_entries_open(struct inode *inode, struct file *filp)
-{
- struct ftrace_entries_info *info;
-
- if (tracing_disabled)
- return -ENODEV;
-
- info = kzalloc(sizeof(*info), GFP_KERNEL);
- if (!info)
- return -ENOMEM;
-
- info->tr = &global_trace;
- info->cpu = (unsigned long)inode->i_private;
-
- filp->private_data = info;
-
- return 0;
-}
-
static ssize_t
tracing_entries_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- struct ftrace_entries_info *info = filp->private_data;
- struct trace_array *tr = info->tr;
+ struct trace_cpu *tc = filp->private_data;
+ struct trace_array *tr = tc->tr;
char buf[64];
int r = 0;
ssize_t ret;
mutex_lock(&trace_types_lock);
- if (info->cpu == RING_BUFFER_ALL_CPUS) {
+ if (tc->cpu == RING_BUFFER_ALL_CPUS) {
int cpu, buf_size_same;
unsigned long size;
@@ -3795,8 +4212,8 @@ tracing_entries_read(struct file *filp, char __user *ubuf,
for_each_tracing_cpu(cpu) {
/* fill in the size from first enabled cpu */
if (size == 0)
- size = tr->data[cpu]->entries;
- if (size != tr->data[cpu]->entries) {
+ size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries;
+ if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) {
buf_size_same = 0;
break;
}
@@ -3812,7 +4229,7 @@ tracing_entries_read(struct file *filp, char __user *ubuf,
} else
r = sprintf(buf, "X\n");
} else
- r = sprintf(buf, "%lu\n", tr->data[info->cpu]->entries >> 10);
+ r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, tc->cpu)->entries >> 10);
mutex_unlock(&trace_types_lock);
@@ -3824,7 +4241,7 @@ static ssize_t
tracing_entries_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- struct ftrace_entries_info *info = filp->private_data;
+ struct trace_cpu *tc = filp->private_data;
unsigned long val;
int ret;
@@ -3839,7 +4256,7 @@ tracing_entries_write(struct file *filp, const char __user *ubuf,
/* value is in KB */
val <<= 10;
- ret = tracing_resize_ring_buffer(val, info->cpu);
+ ret = tracing_resize_ring_buffer(tc->tr, val, tc->cpu);
if (ret < 0)
return ret;
@@ -3848,16 +4265,6 @@ tracing_entries_write(struct file *filp, const char __user *ubuf,
return cnt;
}
-static int
-tracing_entries_release(struct inode *inode, struct file *filp)
-{
- struct ftrace_entries_info *info = filp->private_data;
-
- kfree(info);
-
- return 0;
-}
-
static ssize_t
tracing_total_entries_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
@@ -3869,7 +4276,7 @@ tracing_total_entries_read(struct file *filp, char __user *ubuf,
mutex_lock(&trace_types_lock);
for_each_tracing_cpu(cpu) {
- size += tr->data[cpu]->entries >> 10;
+ size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10;
if (!ring_buffer_expanded)
expanded_size += trace_buf_size >> 10;
}
@@ -3899,11 +4306,13 @@ tracing_free_buffer_write(struct file *filp, const char __user *ubuf,
static int
tracing_free_buffer_release(struct inode *inode, struct file *filp)
{
+ struct trace_array *tr = inode->i_private;
+
/* disable tracing ? */
if (trace_flags & TRACE_ITER_STOP_ON_FREE)
tracing_off();
/* resize the ring buffer to 0 */
- tracing_resize_ring_buffer(0, RING_BUFFER_ALL_CPUS);
+ tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS);
return 0;
}
@@ -3972,7 +4381,7 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
local_save_flags(irq_flags);
size = sizeof(*entry) + cnt + 2; /* possible \n added */
- buffer = global_trace.buffer;
+ buffer = global_trace.trace_buffer.buffer;
event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size,
irq_flags, preempt_count());
if (!event) {
@@ -4014,13 +4423,14 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
static int tracing_clock_show(struct seq_file *m, void *v)
{
+ struct trace_array *tr = m->private;
int i;
for (i = 0; i < ARRAY_SIZE(trace_clocks); i++)
seq_printf(m,
"%s%s%s%s", i ? " " : "",
- i == trace_clock_id ? "[" : "", trace_clocks[i].name,
- i == trace_clock_id ? "]" : "");
+ i == tr->clock_id ? "[" : "", trace_clocks[i].name,
+ i == tr->clock_id ? "]" : "");
seq_putc(m, '\n');
return 0;
@@ -4029,6 +4439,8 @@ static int tracing_clock_show(struct seq_file *m, void *v)
static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *fpos)
{
+ struct seq_file *m = filp->private_data;
+ struct trace_array *tr = m->private;
char buf[64];
const char *clockstr;
int i;
@@ -4050,20 +4462,23 @@ static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf,
if (i == ARRAY_SIZE(trace_clocks))
return -EINVAL;
- trace_clock_id = i;
-
mutex_lock(&trace_types_lock);
- ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func);
- if (max_tr.buffer)
- ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func);
+ tr->clock_id = i;
+
+ ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func);
/*
* New clock may not be consistent with the previous clock.
* Reset the buffer so that it doesn't have incomparable timestamps.
*/
- tracing_reset_online_cpus(&global_trace);
- tracing_reset_online_cpus(&max_tr);
+ tracing_reset_online_cpus(&global_trace.trace_buffer);
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+ if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer)
+ ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func);
+ tracing_reset_online_cpus(&global_trace.max_buffer);
+#endif
mutex_unlock(&trace_types_lock);
@@ -4076,20 +4491,45 @@ static int tracing_clock_open(struct inode *inode, struct file *file)
{
if (tracing_disabled)
return -ENODEV;
- return single_open(file, tracing_clock_show, NULL);
+
+ return single_open(file, tracing_clock_show, inode->i_private);
}
+struct ftrace_buffer_info {
+ struct trace_iterator iter;
+ void *spare;
+ unsigned int read;
+};
+
#ifdef CONFIG_TRACER_SNAPSHOT
static int tracing_snapshot_open(struct inode *inode, struct file *file)
{
+ struct trace_cpu *tc = inode->i_private;
struct trace_iterator *iter;
+ struct seq_file *m;
int ret = 0;
if (file->f_mode & FMODE_READ) {
iter = __tracing_open(inode, file, true);
if (IS_ERR(iter))
ret = PTR_ERR(iter);
+ } else {
+ /* Writes still need the seq_file to hold the private data */
+ m = kzalloc(sizeof(*m), GFP_KERNEL);
+ if (!m)
+ return -ENOMEM;
+ iter = kzalloc(sizeof(*iter), GFP_KERNEL);
+ if (!iter) {
+ kfree(m);
+ return -ENOMEM;
+ }
+ iter->tr = tc->tr;
+ iter->trace_buffer = &tc->tr->max_buffer;
+ iter->cpu_file = tc->cpu;
+ m->private = iter;
+ file->private_data = m;
}
+
return ret;
}
@@ -4097,6 +4537,9 @@ static ssize_t
tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt,
loff_t *ppos)
{
+ struct seq_file *m = filp->private_data;
+ struct trace_iterator *iter = m->private;
+ struct trace_array *tr = iter->tr;
unsigned long val;
int ret;
@@ -4110,42 +4553,48 @@ tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt,
mutex_lock(&trace_types_lock);
- if (current_trace->use_max_tr) {
+ if (tr->current_trace->use_max_tr) {
ret = -EBUSY;
goto out;
}
switch (val) {
case 0:
- if (current_trace->allocated_snapshot) {
- /* free spare buffer */
- ring_buffer_resize(max_tr.buffer, 1,
- RING_BUFFER_ALL_CPUS);
- set_buffer_entries(&max_tr, 1);
- tracing_reset_online_cpus(&max_tr);
- current_trace->allocated_snapshot = false;
+ if (iter->cpu_file != RING_BUFFER_ALL_CPUS) {
+ ret = -EINVAL;
+ break;
}
+ if (tr->allocated_snapshot)
+ free_snapshot(tr);
break;
case 1:
- if (!current_trace->allocated_snapshot) {
- /* allocate spare buffer */
- ret = resize_buffer_duplicate_size(&max_tr,
- &global_trace, RING_BUFFER_ALL_CPUS);
+/* Only allow per-cpu swap if the ring buffer supports it */
+#ifndef CONFIG_RING_BUFFER_ALLOW_SWAP
+ if (iter->cpu_file != RING_BUFFER_ALL_CPUS) {
+ ret = -EINVAL;
+ break;
+ }
+#endif
+ if (!tr->allocated_snapshot) {
+ ret = alloc_snapshot(tr);
if (ret < 0)
break;
- current_trace->allocated_snapshot = true;
}
-
local_irq_disable();
/* Now, we're going to swap */
- update_max_tr(&global_trace, current, smp_processor_id());
+ if (iter->cpu_file == RING_BUFFER_ALL_CPUS)
+ update_max_tr(tr, current, smp_processor_id());
+ else
+ update_max_tr_single(tr, current, iter->cpu_file);
local_irq_enable();
break;
default:
- if (current_trace->allocated_snapshot)
- tracing_reset_online_cpus(&max_tr);
- else
- ret = -EINVAL;
+ if (tr->allocated_snapshot) {
+ if (iter->cpu_file == RING_BUFFER_ALL_CPUS)
+ tracing_reset_online_cpus(&tr->max_buffer);
+ else
+ tracing_reset(&tr->max_buffer, iter->cpu_file);
+ }
break;
}
@@ -4157,6 +4606,51 @@ out:
mutex_unlock(&trace_types_lock);
return ret;
}
+
+static int tracing_snapshot_release(struct inode *inode, struct file *file)
+{
+ struct seq_file *m = file->private_data;
+
+ if (file->f_mode & FMODE_READ)
+ return tracing_release(inode, file);
+
+ /* If write only, the seq_file is just a stub */
+ if (m)
+ kfree(m->private);
+ kfree(m);
+
+ return 0;
+}
+
+static int tracing_buffers_open(struct inode *inode, struct file *filp);
+static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf,
+ size_t count, loff_t *ppos);
+static int tracing_buffers_release(struct inode *inode, struct file *file);
+static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos,
+ struct pipe_inode_info *pipe, size_t len, unsigned int flags);
+
+static int snapshot_raw_open(struct inode *inode, struct file *filp)
+{
+ struct ftrace_buffer_info *info;
+ int ret;
+
+ ret = tracing_buffers_open(inode, filp);
+ if (ret < 0)
+ return ret;
+
+ info = filp->private_data;
+
+ if (info->iter.trace->use_max_tr) {
+ tracing_buffers_release(inode, filp);
+ return -EBUSY;
+ }
+
+ info->iter.snapshot = true;
+ info->iter.trace_buffer = &info->iter.tr->max_buffer;
+
+ return ret;
+}
+
#endif /* CONFIG_TRACER_SNAPSHOT */
@@ -4184,10 +4678,9 @@ static const struct file_operations tracing_pipe_fops = {
};
static const struct file_operations tracing_entries_fops = {
- .open = tracing_entries_open,
+ .open = tracing_open_generic,
.read = tracing_entries_read,
.write = tracing_entries_write,
- .release = tracing_entries_release,
.llseek = generic_file_llseek,
};
@@ -4222,20 +4715,23 @@ static const struct file_operations snapshot_fops = {
.read = seq_read,
.write = tracing_snapshot_write,
.llseek = tracing_seek,
- .release = tracing_release,
+ .release = tracing_snapshot_release,
};
-#endif /* CONFIG_TRACER_SNAPSHOT */
-struct ftrace_buffer_info {
- struct trace_array *tr;
- void *spare;
- int cpu;
- unsigned int read;
+static const struct file_operations snapshot_raw_fops = {
+ .open = snapshot_raw_open,
+ .read = tracing_buffers_read,
+ .release = tracing_buffers_release,
+ .splice_read = tracing_buffers_splice_read,
+ .llseek = no_llseek,
};
+#endif /* CONFIG_TRACER_SNAPSHOT */
+
static int tracing_buffers_open(struct inode *inode, struct file *filp)
{
- int cpu = (int)(long)inode->i_private;
+ struct trace_cpu *tc = inode->i_private;
+ struct trace_array *tr = tc->tr;
struct ftrace_buffer_info *info;
if (tracing_disabled)
@@ -4245,72 +4741,131 @@ static int tracing_buffers_open(struct inode *inode, struct file *filp)
if (!info)
return -ENOMEM;
- info->tr = &global_trace;
- info->cpu = cpu;
- info->spare = NULL;
+ mutex_lock(&trace_types_lock);
+
+ tr->ref++;
+
+ info->iter.tr = tr;
+ info->iter.cpu_file = tc->cpu;
+ info->iter.trace = tr->current_trace;
+ info->iter.trace_buffer = &tr->trace_buffer;
+ info->spare = NULL;
/* Force reading ring buffer for first read */
- info->read = (unsigned int)-1;
+ info->read = (unsigned int)-1;
filp->private_data = info;
+ mutex_unlock(&trace_types_lock);
+
return nonseekable_open(inode, filp);
}
+static unsigned int
+tracing_buffers_poll(struct file *filp, poll_table *poll_table)
+{
+ struct ftrace_buffer_info *info = filp->private_data;
+ struct trace_iterator *iter = &info->iter;
+
+ return trace_poll(iter, filp, poll_table);
+}
+
static ssize_t
tracing_buffers_read(struct file *filp, char __user *ubuf,
size_t count, loff_t *ppos)
{
struct ftrace_buffer_info *info = filp->private_data;
+ struct trace_iterator *iter = &info->iter;
ssize_t ret;
- size_t size;
+ ssize_t size;
if (!count)
return 0;
+ mutex_lock(&trace_types_lock);
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+ if (iter->snapshot && iter->tr->current_trace->use_max_tr) {
+ size = -EBUSY;
+ goto out_unlock;
+ }
+#endif
+
if (!info->spare)
- info->spare = ring_buffer_alloc_read_page(info->tr->buffer, info->cpu);
+ info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer,
+ iter->cpu_file);
+ size = -ENOMEM;
if (!info->spare)
- return -ENOMEM;
+ goto out_unlock;
/* Do we have previous read data to read? */
if (info->read < PAGE_SIZE)
goto read;
- trace_access_lock(info->cpu);
- ret = ring_buffer_read_page(info->tr->buffer,
+ again:
+ trace_access_lock(iter->cpu_file);
+ ret = ring_buffer_read_page(iter->trace_buffer->buffer,
&info->spare,
count,
- info->cpu, 0);
- trace_access_unlock(info->cpu);
- if (ret < 0)
- return 0;
+ iter->cpu_file, 0);
+ trace_access_unlock(iter->cpu_file);
- info->read = 0;
+ if (ret < 0) {
+ if (trace_empty(iter)) {
+ if ((filp->f_flags & O_NONBLOCK)) {
+ size = -EAGAIN;
+ goto out_unlock;
+ }
+ mutex_unlock(&trace_types_lock);
+ iter->trace->wait_pipe(iter);
+ mutex_lock(&trace_types_lock);
+ if (signal_pending(current)) {
+ size = -EINTR;
+ goto out_unlock;
+ }
+ goto again;
+ }
+ size = 0;
+ goto out_unlock;
+ }
-read:
+ info->read = 0;
+ read:
size = PAGE_SIZE - info->read;
if (size > count)
size = count;
ret = copy_to_user(ubuf, info->spare + info->read, size);
- if (ret == size)
- return -EFAULT;
+ if (ret == size) {
+ size = -EFAULT;
+ goto out_unlock;
+ }
size -= ret;
*ppos += size;
info->read += size;
+ out_unlock:
+ mutex_unlock(&trace_types_lock);
+
return size;
}
static int tracing_buffers_release(struct inode *inode, struct file *file)
{
struct ftrace_buffer_info *info = file->private_data;
+ struct trace_iterator *iter = &info->iter;
+
+ mutex_lock(&trace_types_lock);
+
+ WARN_ON(!iter->tr->ref);
+ iter->tr->ref--;
if (info->spare)
- ring_buffer_free_read_page(info->tr->buffer, info->spare);
+ ring_buffer_free_read_page(iter->trace_buffer->buffer, info->spare);
kfree(info);
+ mutex_unlock(&trace_types_lock);
+
return 0;
}
@@ -4375,6 +4930,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
unsigned int flags)
{
struct ftrace_buffer_info *info = file->private_data;
+ struct trace_iterator *iter = &info->iter;
struct partial_page partial_def[PIPE_DEF_BUFFERS];
struct page *pages_def[PIPE_DEF_BUFFERS];
struct splice_pipe_desc spd = {
@@ -4387,10 +4943,21 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
};
struct buffer_ref *ref;
int entries, size, i;
- size_t ret;
+ ssize_t ret;
- if (splice_grow_spd(pipe, &spd))
- return -ENOMEM;
+ mutex_lock(&trace_types_lock);
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+ if (iter->snapshot && iter->tr->current_trace->use_max_tr) {
+ ret = -EBUSY;
+ goto out;
+ }
+#endif
+
+ if (splice_grow_spd(pipe, &spd)) {
+ ret = -ENOMEM;
+ goto out;
+ }
if (*ppos & (PAGE_SIZE - 1)) {
ret = -EINVAL;
@@ -4405,8 +4972,9 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
len &= PAGE_MASK;
}
- trace_access_lock(info->cpu);
- entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu);
+ again:
+ trace_access_lock(iter->cpu_file);
+ entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file);
for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) {
struct page *page;
@@ -4417,15 +4985,15 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
break;
ref->ref = 1;
- ref->buffer = info->tr->buffer;
- ref->page = ring_buffer_alloc_read_page(ref->buffer, info->cpu);
+ ref->buffer = iter->trace_buffer->buffer;
+ ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file);
if (!ref->page) {
kfree(ref);
break;
}
r = ring_buffer_read_page(ref->buffer, &ref->page,
- len, info->cpu, 1);
+ len, iter->cpu_file, 1);
if (r < 0) {
ring_buffer_free_read_page(ref->buffer, ref->page);
kfree(ref);
@@ -4449,31 +5017,40 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
spd.nr_pages++;
*ppos += PAGE_SIZE;
- entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu);
+ entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file);
}
- trace_access_unlock(info->cpu);
+ trace_access_unlock(iter->cpu_file);
spd.nr_pages = i;
/* did we read anything? */
if (!spd.nr_pages) {
- if (flags & SPLICE_F_NONBLOCK)
+ if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) {
ret = -EAGAIN;
- else
- ret = 0;
- /* TODO: block */
- goto out;
+ goto out;
+ }
+ mutex_unlock(&trace_types_lock);
+ iter->trace->wait_pipe(iter);
+ mutex_lock(&trace_types_lock);
+ if (signal_pending(current)) {
+ ret = -EINTR;
+ goto out;
+ }
+ goto again;
}
ret = splice_to_pipe(pipe, &spd);
splice_shrink_spd(&spd);
out:
+ mutex_unlock(&trace_types_lock);
+
return ret;
}
static const struct file_operations tracing_buffers_fops = {
.open = tracing_buffers_open,
.read = tracing_buffers_read,
+ .poll = tracing_buffers_poll,
.release = tracing_buffers_release,
.splice_read = tracing_buffers_splice_read,
.llseek = no_llseek,
@@ -4483,12 +5060,14 @@ static ssize_t
tracing_stats_read(struct file *filp, char __user *ubuf,
size_t count, loff_t *ppos)
{
- unsigned long cpu = (unsigned long)filp->private_data;
- struct trace_array *tr = &global_trace;
+ struct trace_cpu *tc = filp->private_data;
+ struct trace_array *tr = tc->tr;
+ struct trace_buffer *trace_buf = &tr->trace_buffer;
struct trace_seq *s;
unsigned long cnt;
unsigned long long t;
unsigned long usec_rem;
+ int cpu = tc->cpu;
s = kmalloc(sizeof(*s), GFP_KERNEL);
if (!s)
@@ -4496,41 +5075,41 @@ tracing_stats_read(struct file *filp, char __user *ubuf,
trace_seq_init(s);
- cnt = ring_buffer_entries_cpu(tr->buffer, cpu);
+ cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu);
trace_seq_printf(s, "entries: %ld\n", cnt);
- cnt = ring_buffer_overrun_cpu(tr->buffer, cpu);
+ cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu);
trace_seq_printf(s, "overrun: %ld\n", cnt);
- cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu);
+ cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu);
trace_seq_printf(s, "commit overrun: %ld\n", cnt);
- cnt = ring_buffer_bytes_cpu(tr->buffer, cpu);
+ cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu);
trace_seq_printf(s, "bytes: %ld\n", cnt);
if (trace_clocks[trace_clock_id].in_ns) {
/* local or global for trace_clock */
- t = ns2usecs(ring_buffer_oldest_event_ts(tr->buffer, cpu));
+ t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu));
usec_rem = do_div(t, USEC_PER_SEC);
trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n",
t, usec_rem);
- t = ns2usecs(ring_buffer_time_stamp(tr->buffer, cpu));
+ t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu));
usec_rem = do_div(t, USEC_PER_SEC);
trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem);
} else {
/* counter or tsc mode for trace_clock */
trace_seq_printf(s, "oldest event ts: %llu\n",
- ring_buffer_oldest_event_ts(tr->buffer, cpu));
+ ring_buffer_oldest_event_ts(trace_buf->buffer, cpu));
trace_seq_printf(s, "now ts: %llu\n",
- ring_buffer_time_stamp(tr->buffer, cpu));
+ ring_buffer_time_stamp(trace_buf->buffer, cpu));
}
- cnt = ring_buffer_dropped_events_cpu(tr->buffer, cpu);
+ cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu);
trace_seq_printf(s, "dropped events: %ld\n", cnt);
- cnt = ring_buffer_read_events_cpu(tr->buffer, cpu);
+ cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu);
trace_seq_printf(s, "read events: %ld\n", cnt);
count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len);
@@ -4582,60 +5161,161 @@ static const struct file_operations tracing_dyn_info_fops = {
.read = tracing_read_dyn_info,
.llseek = generic_file_llseek,
};
-#endif
+#endif /* CONFIG_DYNAMIC_FTRACE */
-static struct dentry *d_tracer;
+#if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE)
+static void
+ftrace_snapshot(unsigned long ip, unsigned long parent_ip, void **data)
+{
+ tracing_snapshot();
+}
-struct dentry *tracing_init_dentry(void)
+static void
+ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, void **data)
+{
+ unsigned long *count = (long *)data;
+
+ if (!*count)
+ return;
+
+ if (*count != -1)
+ (*count)--;
+
+ tracing_snapshot();
+}
+
+static int
+ftrace_snapshot_print(struct seq_file *m, unsigned long ip,
+ struct ftrace_probe_ops *ops, void *data)
+{
+ long count = (long)data;
+
+ seq_printf(m, "%ps:", (void *)ip);
+
+ seq_printf(m, "snapshot");
+
+ if (count == -1)
+ seq_printf(m, ":unlimited\n");
+ else
+ seq_printf(m, ":count=%ld\n", count);
+
+ return 0;
+}
+
+static struct ftrace_probe_ops snapshot_probe_ops = {
+ .func = ftrace_snapshot,
+ .print = ftrace_snapshot_print,
+};
+
+static struct ftrace_probe_ops snapshot_count_probe_ops = {
+ .func = ftrace_count_snapshot,
+ .print = ftrace_snapshot_print,
+};
+
+static int
+ftrace_trace_snapshot_callback(struct ftrace_hash *hash,
+ char *glob, char *cmd, char *param, int enable)
+{
+ struct ftrace_probe_ops *ops;
+ void *count = (void *)-1;
+ char *number;
+ int ret;
+
+ /* hash funcs only work with set_ftrace_filter */
+ if (!enable)
+ return -EINVAL;
+
+ ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops;
+
+ if (glob[0] == '!') {
+ unregister_ftrace_function_probe_func(glob+1, ops);
+ return 0;
+ }
+
+ if (!param)
+ goto out_reg;
+
+ number = strsep(&param, ":");
+
+ if (!strlen(number))
+ goto out_reg;
+
+ /*
+ * We use the callback data field (which is a pointer)
+ * as our counter.
+ */
+ ret = kstrtoul(number, 0, (unsigned long *)&count);
+ if (ret)
+ return ret;
+
+ out_reg:
+ ret = register_ftrace_function_probe(glob, ops, count);
+
+ if (ret >= 0)
+ alloc_snapshot(&global_trace);
+
+ return ret < 0 ? ret : 0;
+}
+
+static struct ftrace_func_command ftrace_snapshot_cmd = {
+ .name = "snapshot",
+ .func = ftrace_trace_snapshot_callback,
+};
+
+static int register_snapshot_cmd(void)
{
- static int once;
+ return register_ftrace_command(&ftrace_snapshot_cmd);
+}
+#else
+static inline int register_snapshot_cmd(void) { return 0; }
+#endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */
- if (d_tracer)
- return d_tracer;
+struct dentry *tracing_init_dentry_tr(struct trace_array *tr)
+{
+ if (tr->dir)
+ return tr->dir;
if (!debugfs_initialized())
return NULL;
- d_tracer = debugfs_create_dir("tracing", NULL);
+ if (tr->flags & TRACE_ARRAY_FL_GLOBAL)
+ tr->dir = debugfs_create_dir("tracing", NULL);
- if (!d_tracer && !once) {
- once = 1;
- pr_warning("Could not create debugfs directory 'tracing'\n");
- return NULL;
- }
+ if (!tr->dir)
+ pr_warn_once("Could not create debugfs directory 'tracing'\n");
- return d_tracer;
+ return tr->dir;
}
-static struct dentry *d_percpu;
+struct dentry *tracing_init_dentry(void)
+{
+ return tracing_init_dentry_tr(&global_trace);
+}
-static struct dentry *tracing_dentry_percpu(void)
+static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu)
{
- static int once;
struct dentry *d_tracer;
- if (d_percpu)
- return d_percpu;
-
- d_tracer = tracing_init_dentry();
+ if (tr->percpu_dir)
+ return tr->percpu_dir;
+ d_tracer = tracing_init_dentry_tr(tr);
if (!d_tracer)
return NULL;
- d_percpu = debugfs_create_dir("per_cpu", d_tracer);
+ tr->percpu_dir = debugfs_create_dir("per_cpu", d_tracer);
- if (!d_percpu && !once) {
- once = 1;
- pr_warning("Could not create debugfs directory 'per_cpu'\n");
- return NULL;
- }
+ WARN_ONCE(!tr->percpu_dir,
+ "Could not create debugfs directory 'per_cpu/%d'\n", cpu);
- return d_percpu;
+ return tr->percpu_dir;
}
-static void tracing_init_debugfs_percpu(long cpu)
+static void
+tracing_init_debugfs_percpu(struct trace_array *tr, long cpu)
{
- struct dentry *d_percpu = tracing_dentry_percpu();
+ struct trace_array_cpu *data = per_cpu_ptr(tr->trace_buffer.data, cpu);
+ struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu);
struct dentry *d_cpu;
char cpu_dir[30]; /* 30 characters should be more than enough */
@@ -4651,20 +5331,28 @@ static void tracing_init_debugfs_percpu(long cpu)
/* per cpu trace_pipe */
trace_create_file("trace_pipe", 0444, d_cpu,
- (void *) cpu, &tracing_pipe_fops);
+ (void *)&data->trace_cpu, &tracing_pipe_fops);
/* per cpu trace */
trace_create_file("trace", 0644, d_cpu,
- (void *) cpu, &tracing_fops);
+ (void *)&data->trace_cpu, &tracing_fops);
trace_create_file("trace_pipe_raw", 0444, d_cpu,
- (void *) cpu, &tracing_buffers_fops);
+ (void *)&data->trace_cpu, &tracing_buffers_fops);
trace_create_file("stats", 0444, d_cpu,
- (void *) cpu, &tracing_stats_fops);
+ (void *)&data->trace_cpu, &tracing_stats_fops);
trace_create_file("buffer_size_kb", 0444, d_cpu,
- (void *) cpu, &tracing_entries_fops);
+ (void *)&data->trace_cpu, &tracing_entries_fops);
+
+#ifdef CONFIG_TRACER_SNAPSHOT
+ trace_create_file("snapshot", 0644, d_cpu,
+ (void *)&data->trace_cpu, &snapshot_fops);
+
+ trace_create_file("snapshot_raw", 0444, d_cpu,
+ (void *)&data->trace_cpu, &snapshot_raw_fops);
+#endif
}
#ifdef CONFIG_FTRACE_SELFTEST
@@ -4675,6 +5363,7 @@ static void tracing_init_debugfs_percpu(long cpu)
struct trace_option_dentry {
struct tracer_opt *opt;
struct tracer_flags *flags;
+ struct trace_array *tr;
struct dentry *entry;
};
@@ -4710,7 +5399,7 @@ trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt,
if (!!(topt->flags->val & topt->opt->bit) != val) {
mutex_lock(&trace_types_lock);
- ret = __set_tracer_option(current_trace, topt->flags,
+ ret = __set_tracer_option(topt->tr->current_trace, topt->flags,
topt->opt, !val);
mutex_unlock(&trace_types_lock);
if (ret)
@@ -4749,6 +5438,7 @@ static ssize_t
trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt,
loff_t *ppos)
{
+ struct trace_array *tr = &global_trace;
long index = (long)filp->private_data;
unsigned long val;
int ret;
@@ -4759,7 +5449,13 @@ trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt,
if (val != 0 && val != 1)
return -EINVAL;
- set_tracer_flags(1 << index, val);
+
+ mutex_lock(&trace_types_lock);
+ ret = set_tracer_flag(tr, 1 << index, val);
+ mutex_unlock(&trace_types_lock);
+
+ if (ret < 0)
+ return ret;
*ppos += cnt;
@@ -4789,40 +5485,41 @@ struct dentry *trace_create_file(const char *name,
}
-static struct dentry *trace_options_init_dentry(void)
+static struct dentry *trace_options_init_dentry(struct trace_array *tr)
{
struct dentry *d_tracer;
- static struct dentry *t_options;
- if (t_options)
- return t_options;
+ if (tr->options)
+ return tr->options;
- d_tracer = tracing_init_dentry();
+ d_tracer = tracing_init_dentry_tr(tr);
if (!d_tracer)
return NULL;
- t_options = debugfs_create_dir("options", d_tracer);
- if (!t_options) {
+ tr->options = debugfs_create_dir("options", d_tracer);
+ if (!tr->options) {
pr_warning("Could not create debugfs directory 'options'\n");
return NULL;
}
- return t_options;
+ return tr->options;
}
static void
-create_trace_option_file(struct trace_option_dentry *topt,
+create_trace_option_file(struct trace_array *tr,
+ struct trace_option_dentry *topt,
struct tracer_flags *flags,
struct tracer_opt *opt)
{
struct dentry *t_options;
- t_options = trace_options_init_dentry();
+ t_options = trace_options_init_dentry(tr);
if (!t_options)
return;
topt->flags = flags;
topt->opt = opt;
+ topt->tr = tr;
topt->entry = trace_create_file(opt->name, 0644, t_options, topt,
&trace_options_fops);
@@ -4830,7 +5527,7 @@ create_trace_option_file(struct trace_option_dentry *topt,
}
static struct trace_option_dentry *
-create_trace_option_files(struct tracer *tracer)
+create_trace_option_files(struct trace_array *tr, struct tracer *tracer)
{
struct trace_option_dentry *topts;
struct tracer_flags *flags;
@@ -4855,7 +5552,7 @@ create_trace_option_files(struct tracer *tracer)
return NULL;
for (cnt = 0; opts[cnt].name; cnt++)
- create_trace_option_file(&topts[cnt], flags,
+ create_trace_option_file(tr, &topts[cnt], flags,
&opts[cnt]);
return topts;
@@ -4878,11 +5575,12 @@ destroy_trace_option_files(struct trace_option_dentry *topts)
}
static struct dentry *
-create_trace_option_core_file(const char *option, long index)
+create_trace_option_core_file(struct trace_array *tr,
+ const char *option, long index)
{
struct dentry *t_options;
- t_options = trace_options_init_dentry();
+ t_options = trace_options_init_dentry(tr);
if (!t_options)
return NULL;
@@ -4890,17 +5588,17 @@ create_trace_option_core_file(const char *option, long index)
&trace_options_core_fops);
}
-static __init void create_trace_options_dir(void)
+static __init void create_trace_options_dir(struct trace_array *tr)
{
struct dentry *t_options;
int i;
- t_options = trace_options_init_dentry();
+ t_options = trace_options_init_dentry(tr);
if (!t_options)
return;
for (i = 0; trace_options[i]; i++)
- create_trace_option_core_file(trace_options[i], i);
+ create_trace_option_core_file(tr, trace_options[i], i);
}
static ssize_t
@@ -4908,7 +5606,7 @@ rb_simple_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
struct trace_array *tr = filp->private_data;
- struct ring_buffer *buffer = tr->buffer;
+ struct ring_buffer *buffer = tr->trace_buffer.buffer;
char buf[64];
int r;
@@ -4927,7 +5625,7 @@ rb_simple_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
struct trace_array *tr = filp->private_data;
- struct ring_buffer *buffer = tr->buffer;
+ struct ring_buffer *buffer = tr->trace_buffer.buffer;
unsigned long val;
int ret;
@@ -4939,12 +5637,12 @@ rb_simple_write(struct file *filp, const char __user *ubuf,
mutex_lock(&trace_types_lock);
if (val) {
ring_buffer_record_on(buffer);
- if (current_trace->start)
- current_trace->start(tr);
+ if (tr->current_trace->start)
+ tr->current_trace->start(tr);
} else {
ring_buffer_record_off(buffer);
- if (current_trace->stop)
- current_trace->stop(tr);
+ if (tr->current_trace->stop)
+ tr->current_trace->stop(tr);
}
mutex_unlock(&trace_types_lock);
}
@@ -4961,23 +5659,310 @@ static const struct file_operations rb_simple_fops = {
.llseek = default_llseek,
};
+struct dentry *trace_instance_dir;
+
+static void
+init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer);
+
+static void init_trace_buffers(struct trace_array *tr, struct trace_buffer *buf)
+{
+ int cpu;
+
+ for_each_tracing_cpu(cpu) {
+ memset(per_cpu_ptr(buf->data, cpu), 0, sizeof(struct trace_array_cpu));
+ per_cpu_ptr(buf->data, cpu)->trace_cpu.cpu = cpu;
+ per_cpu_ptr(buf->data, cpu)->trace_cpu.tr = tr;
+ }
+}
+
+static int
+allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size)
+{
+ enum ring_buffer_flags rb_flags;
+
+ rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0;
+
+ buf->buffer = ring_buffer_alloc(size, rb_flags);
+ if (!buf->buffer)
+ return -ENOMEM;
+
+ buf->data = alloc_percpu(struct trace_array_cpu);
+ if (!buf->data) {
+ ring_buffer_free(buf->buffer);
+ return -ENOMEM;
+ }
+
+ init_trace_buffers(tr, buf);
+
+ /* Allocate the first page for all buffers */
+ set_buffer_entries(&tr->trace_buffer,
+ ring_buffer_size(tr->trace_buffer.buffer, 0));
+
+ return 0;
+}
+
+static int allocate_trace_buffers(struct trace_array *tr, int size)
+{
+ int ret;
+
+ ret = allocate_trace_buffer(tr, &tr->trace_buffer, size);
+ if (ret)
+ return ret;
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+ ret = allocate_trace_buffer(tr, &tr->max_buffer,
+ allocate_snapshot ? size : 1);
+ if (WARN_ON(ret)) {
+ ring_buffer_free(tr->trace_buffer.buffer);
+ free_percpu(tr->trace_buffer.data);
+ return -ENOMEM;
+ }
+ tr->allocated_snapshot = allocate_snapshot;
+
+ /*
+ * Only the top level trace array gets its snapshot allocated
+ * from the kernel command line.
+ */
+ allocate_snapshot = false;
+#endif
+ return 0;
+}
+
+static int new_instance_create(const char *name)
+{
+ struct trace_array *tr;
+ int ret;
+
+ mutex_lock(&trace_types_lock);
+
+ ret = -EEXIST;
+ list_for_each_entry(tr, &ftrace_trace_arrays, list) {
+ if (tr->name && strcmp(tr->name, name) == 0)
+ goto out_unlock;
+ }
+
+ ret = -ENOMEM;
+ tr = kzalloc(sizeof(*tr), GFP_KERNEL);
+ if (!tr)
+ goto out_unlock;
+
+ tr->name = kstrdup(name, GFP_KERNEL);
+ if (!tr->name)
+ goto out_free_tr;
+
+ raw_spin_lock_init(&tr->start_lock);
+
+ tr->current_trace = &nop_trace;
+
+ INIT_LIST_HEAD(&tr->systems);
+ INIT_LIST_HEAD(&tr->events);
+
+ if (allocate_trace_buffers(tr, trace_buf_size) < 0)
+ goto out_free_tr;
+
+ /* Holder for file callbacks */
+ tr->trace_cpu.cpu = RING_BUFFER_ALL_CPUS;
+ tr->trace_cpu.tr = tr;
+
+ tr->dir = debugfs_create_dir(name, trace_instance_dir);
+ if (!tr->dir)
+ goto out_free_tr;
+
+ ret = event_trace_add_tracer(tr->dir, tr);
+ if (ret)
+ goto out_free_tr;
+
+ init_tracer_debugfs(tr, tr->dir);
+
+ list_add(&tr->list, &ftrace_trace_arrays);
+
+ mutex_unlock(&trace_types_lock);
+
+ return 0;
+
+ out_free_tr:
+ if (tr->trace_buffer.buffer)
+ ring_buffer_free(tr->trace_buffer.buffer);
+ kfree(tr->name);
+ kfree(tr);
+
+ out_unlock:
+ mutex_unlock(&trace_types_lock);
+
+ return ret;
+
+}
+
+static int instance_delete(const char *name)
+{
+ struct trace_array *tr;
+ int found = 0;
+ int ret;
+
+ mutex_lock(&trace_types_lock);
+
+ ret = -ENODEV;
+ list_for_each_entry(tr, &ftrace_trace_arrays, list) {
+ if (tr->name && strcmp(tr->name, name) == 0) {
+ found = 1;
+ break;
+ }
+ }
+ if (!found)
+ goto out_unlock;
+
+ ret = -EBUSY;
+ if (tr->ref)
+ goto out_unlock;
+
+ list_del(&tr->list);
+
+ event_trace_del_tracer(tr);
+ debugfs_remove_recursive(tr->dir);
+ free_percpu(tr->trace_buffer.data);
+ ring_buffer_free(tr->trace_buffer.buffer);
+
+ kfree(tr->name);
+ kfree(tr);
+
+ ret = 0;
+
+ out_unlock:
+ mutex_unlock(&trace_types_lock);
+
+ return ret;
+}
+
+static int instance_mkdir (struct inode *inode, struct dentry *dentry, umode_t mode)
+{
+ struct dentry *parent;
+ int ret;
+
+ /* Paranoid: Make sure the parent is the "instances" directory */
+ parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias);
+ if (WARN_ON_ONCE(parent != trace_instance_dir))
+ return -ENOENT;
+
+ /*
+ * The inode mutex is locked, but debugfs_create_dir() will also
+ * take the mutex. As the instances directory can not be destroyed
+ * or changed in any other way, it is safe to unlock it, and
+ * let the dentry try. If two users try to make the same dir at
+ * the same time, then the new_instance_create() will determine the
+ * winner.
+ */
+ mutex_unlock(&inode->i_mutex);
+
+ ret = new_instance_create(dentry->d_iname);
+
+ mutex_lock(&inode->i_mutex);
+
+ return ret;
+}
+
+static int instance_rmdir(struct inode *inode, struct dentry *dentry)
+{
+ struct dentry *parent;
+ int ret;
+
+ /* Paranoid: Make sure the parent is the "instances" directory */
+ parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias);
+ if (WARN_ON_ONCE(parent != trace_instance_dir))
+ return -ENOENT;
+
+ /* The caller did a dget() on dentry */
+ mutex_unlock(&dentry->d_inode->i_mutex);
+
+ /*
+ * The inode mutex is locked, but debugfs_create_dir() will also
+ * take the mutex. As the instances directory can not be destroyed
+ * or changed in any other way, it is safe to unlock it, and
+ * let the dentry try. If two users try to make the same dir at
+ * the same time, then the instance_delete() will determine the
+ * winner.
+ */
+ mutex_unlock(&inode->i_mutex);
+
+ ret = instance_delete(dentry->d_iname);
+
+ mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
+ mutex_lock(&dentry->d_inode->i_mutex);
+
+ return ret;
+}
+
+static const struct inode_operations instance_dir_inode_operations = {
+ .lookup = simple_lookup,
+ .mkdir = instance_mkdir,
+ .rmdir = instance_rmdir,
+};
+
+static __init void create_trace_instances(struct dentry *d_tracer)
+{
+ trace_instance_dir = debugfs_create_dir("instances", d_tracer);
+ if (WARN_ON(!trace_instance_dir))
+ return;
+
+ /* Hijack the dir inode operations, to allow mkdir */
+ trace_instance_dir->d_inode->i_op = &instance_dir_inode_operations;
+}
+
+static void
+init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer)
+{
+ int cpu;
+
+ trace_create_file("trace_options", 0644, d_tracer,
+ tr, &tracing_iter_fops);
+
+ trace_create_file("trace", 0644, d_tracer,
+ (void *)&tr->trace_cpu, &tracing_fops);
+
+ trace_create_file("trace_pipe", 0444, d_tracer,
+ (void *)&tr->trace_cpu, &tracing_pipe_fops);
+
+ trace_create_file("buffer_size_kb", 0644, d_tracer,
+ (void *)&tr->trace_cpu, &tracing_entries_fops);
+
+ trace_create_file("buffer_total_size_kb", 0444, d_tracer,
+ tr, &tracing_total_entries_fops);
+
+ trace_create_file("free_buffer", 0644, d_tracer,
+ tr, &tracing_free_buffer_fops);
+
+ trace_create_file("trace_marker", 0220, d_tracer,
+ tr, &tracing_mark_fops);
+
+ trace_create_file("trace_clock", 0644, d_tracer, tr,
+ &trace_clock_fops);
+
+ trace_create_file("tracing_on", 0644, d_tracer,
+ tr, &rb_simple_fops);
+
+#ifdef CONFIG_TRACER_SNAPSHOT
+ trace_create_file("snapshot", 0644, d_tracer,
+ (void *)&tr->trace_cpu, &snapshot_fops);
+#endif
+
+ for_each_tracing_cpu(cpu)
+ tracing_init_debugfs_percpu(tr, cpu);
+
+}
+
static __init int tracer_init_debugfs(void)
{
struct dentry *d_tracer;
- int cpu;
trace_access_lock_init();
d_tracer = tracing_init_dentry();
+ if (!d_tracer)
+ return 0;
- trace_create_file("trace_options", 0644, d_tracer,
- NULL, &tracing_iter_fops);
+ init_tracer_debugfs(&global_trace, d_tracer);
trace_create_file("tracing_cpumask", 0644, d_tracer,
- NULL, &tracing_cpumask_fops);
-
- trace_create_file("trace", 0644, d_tracer,
- (void *) TRACE_PIPE_ALL_CPU, &tracing_fops);
+ &global_trace, &tracing_cpumask_fops);
trace_create_file("available_tracers", 0444, d_tracer,
&global_trace, &show_traces_fops);
@@ -4996,44 +5981,17 @@ static __init int tracer_init_debugfs(void)
trace_create_file("README", 0444, d_tracer,
NULL, &tracing_readme_fops);
- trace_create_file("trace_pipe", 0444, d_tracer,
- (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops);
-
- trace_create_file("buffer_size_kb", 0644, d_tracer,
- (void *) RING_BUFFER_ALL_CPUS, &tracing_entries_fops);
-
- trace_create_file("buffer_total_size_kb", 0444, d_tracer,
- &global_trace, &tracing_total_entries_fops);
-
- trace_create_file("free_buffer", 0644, d_tracer,
- &global_trace, &tracing_free_buffer_fops);
-
- trace_create_file("trace_marker", 0220, d_tracer,
- NULL, &tracing_mark_fops);
-
trace_create_file("saved_cmdlines", 0444, d_tracer,
NULL, &tracing_saved_cmdlines_fops);
- trace_create_file("trace_clock", 0644, d_tracer, NULL,
- &trace_clock_fops);
-
- trace_create_file("tracing_on", 0644, d_tracer,
- &global_trace, &rb_simple_fops);
-
#ifdef CONFIG_DYNAMIC_FTRACE
trace_create_file("dyn_ftrace_total_info", 0444, d_tracer,
&ftrace_update_tot_cnt, &tracing_dyn_info_fops);
#endif
-#ifdef CONFIG_TRACER_SNAPSHOT
- trace_create_file("snapshot", 0644, d_tracer,
- (void *) TRACE_PIPE_ALL_CPU, &snapshot_fops);
-#endif
-
- create_trace_options_dir();
+ create_trace_instances(d_tracer);
- for_each_tracing_cpu(cpu)
- tracing_init_debugfs_percpu(cpu);
+ create_trace_options_dir(&global_trace);
return 0;
}
@@ -5089,8 +6047,8 @@ void
trace_printk_seq(struct trace_seq *s)
{
/* Probably should print a warning here. */
- if (s->len >= 1000)
- s->len = 1000;
+ if (s->len >= TRACE_MAX_PRINT)
+ s->len = TRACE_MAX_PRINT;
/* should be zero ended, but we are paranoid. */
s->buffer[s->len] = 0;
@@ -5103,46 +6061,43 @@ trace_printk_seq(struct trace_seq *s)
void trace_init_global_iter(struct trace_iterator *iter)
{
iter->tr = &global_trace;
- iter->trace = current_trace;
- iter->cpu_file = TRACE_PIPE_ALL_CPU;
+ iter->trace = iter->tr->current_trace;
+ iter->cpu_file = RING_BUFFER_ALL_CPUS;
+ iter->trace_buffer = &global_trace.trace_buffer;
}
-static void
-__ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode)
+void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
{
- static arch_spinlock_t ftrace_dump_lock =
- (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
/* use static because iter can be a bit big for the stack */
static struct trace_iterator iter;
+ static atomic_t dump_running;
unsigned int old_userobj;
- static int dump_ran;
unsigned long flags;
int cnt = 0, cpu;
- /* only one dump */
- local_irq_save(flags);
- arch_spin_lock(&ftrace_dump_lock);
- if (dump_ran)
- goto out;
-
- dump_ran = 1;
+ /* Only allow one dump user at a time. */
+ if (atomic_inc_return(&dump_running) != 1) {
+ atomic_dec(&dump_running);
+ return;
+ }
+ /*
+ * Always turn off tracing when we dump.
+ * We don't need to show trace output of what happens
+ * between multiple crashes.
+ *
+ * If the user does a sysrq-z, then they can re-enable
+ * tracing with echo 1 > tracing_on.
+ */
tracing_off();
- /* Did function tracer already get disabled? */
- if (ftrace_is_dead()) {
- printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n");
- printk("# MAY BE MISSING FUNCTION EVENTS\n");
- }
-
- if (disable_tracing)
- ftrace_kill();
+ local_irq_save(flags);
/* Simulate the iterator */
trace_init_global_iter(&iter);
for_each_tracing_cpu(cpu) {
- atomic_inc(&iter.tr->data[cpu]->disabled);
+ atomic_inc(&per_cpu_ptr(iter.tr->trace_buffer.data, cpu)->disabled);
}
old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ;
@@ -5152,7 +6107,7 @@ __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode)
switch (oops_dump_mode) {
case DUMP_ALL:
- iter.cpu_file = TRACE_PIPE_ALL_CPU;
+ iter.cpu_file = RING_BUFFER_ALL_CPUS;
break;
case DUMP_ORIG:
iter.cpu_file = raw_smp_processor_id();
@@ -5161,11 +6116,17 @@ __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode)
goto out_enable;
default:
printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n");
- iter.cpu_file = TRACE_PIPE_ALL_CPU;
+ iter.cpu_file = RING_BUFFER_ALL_CPUS;
}
printk(KERN_TRACE "Dumping ftrace buffer:\n");
+ /* Did function tracer already get disabled? */
+ if (ftrace_is_dead()) {
+ printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n");
+ printk("# MAY BE MISSING FUNCTION EVENTS\n");
+ }
+
/*
* We need to stop all tracing on all CPUS to read the
* the next buffer. This is a bit expensive, but is
@@ -5205,33 +6166,19 @@ __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode)
printk(KERN_TRACE "---------------------------------\n");
out_enable:
- /* Re-enable tracing if requested */
- if (!disable_tracing) {
- trace_flags |= old_userobj;
+ trace_flags |= old_userobj;
- for_each_tracing_cpu(cpu) {
- atomic_dec(&iter.tr->data[cpu]->disabled);
- }
- tracing_on();
+ for_each_tracing_cpu(cpu) {
+ atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled);
}
-
- out:
- arch_spin_unlock(&ftrace_dump_lock);
+ atomic_dec(&dump_running);
local_irq_restore(flags);
}
-
-/* By default: disable tracing after the dump */
-void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
-{
- __ftrace_dump(true, oops_dump_mode);
-}
EXPORT_SYMBOL_GPL(ftrace_dump);
__init static int tracer_alloc_buffers(void)
{
int ring_buf_size;
- enum ring_buffer_flags rb_flags;
- int i;
int ret = -ENOMEM;
@@ -5252,49 +6199,27 @@ __init static int tracer_alloc_buffers(void)
else
ring_buf_size = 1;
- rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0;
-
cpumask_copy(tracing_buffer_mask, cpu_possible_mask);
cpumask_copy(tracing_cpumask, cpu_all_mask);
+ raw_spin_lock_init(&global_trace.start_lock);
+
/* TODO: make the number of buffers hot pluggable with CPUS */
- global_trace.buffer = ring_buffer_alloc(ring_buf_size, rb_flags);
- if (!global_trace.buffer) {
+ if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) {
printk(KERN_ERR "tracer: failed to allocate ring buffer!\n");
WARN_ON(1);
goto out_free_cpumask;
}
+
if (global_trace.buffer_disabled)
tracing_off();
-
-#ifdef CONFIG_TRACER_MAX_TRACE
- max_tr.buffer = ring_buffer_alloc(1, rb_flags);
- if (!max_tr.buffer) {
- printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n");
- WARN_ON(1);
- ring_buffer_free(global_trace.buffer);
- goto out_free_cpumask;
- }
-#endif
-
- /* Allocate the first page for all buffers */
- for_each_tracing_cpu(i) {
- global_trace.data[i] = &per_cpu(global_trace_cpu, i);
- max_tr.data[i] = &per_cpu(max_tr_data, i);
- }
-
- set_buffer_entries(&global_trace,
- ring_buffer_size(global_trace.buffer, 0));
-#ifdef CONFIG_TRACER_MAX_TRACE
- set_buffer_entries(&max_tr, 1);
-#endif
-
trace_init_cmdlines();
- init_irq_work(&trace_work_wakeup, trace_wake_up);
register_tracer(&nop_trace);
+ global_trace.current_trace = &nop_trace;
+
/* All seems OK, enable tracing */
tracing_disabled = 0;
@@ -5303,16 +6228,32 @@ __init static int tracer_alloc_buffers(void)
register_die_notifier(&trace_die_notifier);
+ global_trace.flags = TRACE_ARRAY_FL_GLOBAL;
+
+ /* Holder for file callbacks */
+ global_trace.trace_cpu.cpu = RING_BUFFER_ALL_CPUS;
+ global_trace.trace_cpu.tr = &global_trace;
+
+ INIT_LIST_HEAD(&global_trace.systems);
+ INIT_LIST_HEAD(&global_trace.events);
+ list_add(&global_trace.list, &ftrace_trace_arrays);
+
while (trace_boot_options) {
char *option;
option = strsep(&trace_boot_options, ",");
- trace_set_options(option);
+ trace_set_options(&global_trace, option);
}
+ register_snapshot_cmd();
+
return 0;
out_free_cpumask:
+ free_percpu(global_trace.trace_buffer.data);
+#ifdef CONFIG_TRACER_MAX_TRACE
+ free_percpu(global_trace.max_buffer.data);
+#endif
free_cpumask_var(tracing_cpumask);
out_free_buffer_mask:
free_cpumask_var(tracing_buffer_mask);