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Diffstat (limited to 'kernel/trace/trace.c')
-rw-r--r--kernel/trace/trace.c201
1 files changed, 151 insertions, 50 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 5c75deeefe30..026e715a0c7a 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -125,19 +125,19 @@ int ftrace_dump_on_oops;
static int tracing_set_tracer(const char *buf);
-#define BOOTUP_TRACER_SIZE 100
-static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata;
+#define MAX_TRACER_SIZE 100
+static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata;
static char *default_bootup_tracer;
-static int __init set_ftrace(char *str)
+static int __init set_cmdline_ftrace(char *str)
{
- strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE);
+ strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE);
default_bootup_tracer = bootup_tracer_buf;
/* We are using ftrace early, expand it */
ring_buffer_expanded = 1;
return 1;
}
-__setup("ftrace=", set_ftrace);
+__setup("ftrace=", set_cmdline_ftrace);
static int __init set_ftrace_dump_on_oops(char *str)
{
@@ -242,13 +242,6 @@ static struct tracer *trace_types __read_mostly;
static struct tracer *current_trace __read_mostly;
/*
- * max_tracer_type_len is used to simplify the allocating of
- * buffers to read userspace tracer names. We keep track of
- * the longest tracer name registered.
- */
-static int max_tracer_type_len;
-
-/*
* trace_types_lock is used to protect the trace_types list.
* This lock is also used to keep user access serialized.
* Accesses from userspace will grab this lock while userspace
@@ -275,12 +268,18 @@ static DEFINE_SPINLOCK(tracing_start_lock);
*/
void trace_wake_up(void)
{
+ int cpu;
+
+ if (trace_flags & TRACE_ITER_BLOCK)
+ return;
/*
* The runqueue_is_locked() can fail, but this is the best we
* have for now:
*/
- if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked())
+ cpu = get_cpu();
+ if (!runqueue_is_locked(cpu))
wake_up(&trace_wait);
+ put_cpu();
}
static int __init set_buf_size(char *str)
@@ -339,6 +338,112 @@ static struct {
int trace_clock_id;
+/*
+ * trace_parser_get_init - gets the buffer for trace parser
+ */
+int trace_parser_get_init(struct trace_parser *parser, int size)
+{
+ memset(parser, 0, sizeof(*parser));
+
+ parser->buffer = kmalloc(size, GFP_KERNEL);
+ if (!parser->buffer)
+ return 1;
+
+ parser->size = size;
+ return 0;
+}
+
+/*
+ * trace_parser_put - frees the buffer for trace parser
+ */
+void trace_parser_put(struct trace_parser *parser)
+{
+ kfree(parser->buffer);
+}
+
+/*
+ * trace_get_user - reads the user input string separated by space
+ * (matched by isspace(ch))
+ *
+ * For each string found the 'struct trace_parser' is updated,
+ * and the function returns.
+ *
+ * Returns number of bytes read.
+ *
+ * See kernel/trace/trace.h for 'struct trace_parser' details.
+ */
+int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char ch;
+ size_t read = 0;
+ ssize_t ret;
+
+ if (!*ppos)
+ trace_parser_clear(parser);
+
+ ret = get_user(ch, ubuf++);
+ if (ret)
+ goto out;
+
+ read++;
+ cnt--;
+
+ /*
+ * The parser is not finished with the last write,
+ * continue reading the user input without skipping spaces.
+ */
+ if (!parser->cont) {
+ /* skip white space */
+ while (cnt && isspace(ch)) {
+ ret = get_user(ch, ubuf++);
+ if (ret)
+ goto out;
+ read++;
+ cnt--;
+ }
+
+ /* only spaces were written */
+ if (isspace(ch)) {
+ *ppos += read;
+ ret = read;
+ goto out;
+ }
+
+ parser->idx = 0;
+ }
+
+ /* read the non-space input */
+ while (cnt && !isspace(ch)) {
+ if (parser->idx < parser->size - 1)
+ parser->buffer[parser->idx++] = ch;
+ else {
+ ret = -EINVAL;
+ goto out;
+ }
+ ret = get_user(ch, ubuf++);
+ if (ret)
+ goto out;
+ read++;
+ cnt--;
+ }
+
+ /* We either got finished input or we have to wait for another call. */
+ if (isspace(ch)) {
+ parser->buffer[parser->idx] = 0;
+ parser->cont = false;
+ } else {
+ parser->cont = true;
+ parser->buffer[parser->idx++] = ch;
+ }
+
+ *ppos += read;
+ ret = read;
+
+out:
+ return ret;
+}
+
ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt)
{
int len;
@@ -513,7 +618,6 @@ __releases(kernel_lock)
__acquires(kernel_lock)
{
struct tracer *t;
- int len;
int ret = 0;
if (!type->name) {
@@ -521,6 +625,11 @@ __acquires(kernel_lock)
return -1;
}
+ if (strlen(type->name) > MAX_TRACER_SIZE) {
+ pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE);
+ return -1;
+ }
+
/*
* When this gets called we hold the BKL which means that
* preemption is disabled. Various trace selftests however
@@ -535,7 +644,7 @@ __acquires(kernel_lock)
for (t = trace_types; t; t = t->next) {
if (strcmp(type->name, t->name) == 0) {
/* already found */
- pr_info("Trace %s already registered\n",
+ pr_info("Tracer %s already registered\n",
type->name);
ret = -1;
goto out;
@@ -586,9 +695,6 @@ __acquires(kernel_lock)
type->next = trace_types;
trace_types = type;
- len = strlen(type->name);
- if (len > max_tracer_type_len)
- max_tracer_type_len = len;
out:
tracing_selftest_running = false;
@@ -597,7 +703,7 @@ __acquires(kernel_lock)
if (ret || !default_bootup_tracer)
goto out_unlock;
- if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE))
+ if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE))
goto out_unlock;
printk(KERN_INFO "Starting tracer '%s'\n", type->name);
@@ -619,14 +725,13 @@ __acquires(kernel_lock)
void unregister_tracer(struct tracer *type)
{
struct tracer **t;
- int len;
mutex_lock(&trace_types_lock);
for (t = &trace_types; *t; t = &(*t)->next) {
if (*t == type)
goto found;
}
- pr_info("Trace %s not registered\n", type->name);
+ pr_info("Tracer %s not registered\n", type->name);
goto out;
found:
@@ -639,17 +744,7 @@ void unregister_tracer(struct tracer *type)
current_trace->stop(&global_trace);
current_trace = &nop_trace;
}
-
- if (strlen(type->name) != max_tracer_type_len)
- goto out;
-
- max_tracer_type_len = 0;
- for (t = &trace_types; *t; t = &(*t)->next) {
- len = strlen((*t)->name);
- if (len > max_tracer_type_len)
- max_tracer_type_len = len;
- }
- out:
+out:
mutex_unlock(&trace_types_lock);
}
@@ -719,6 +814,11 @@ static void trace_init_cmdlines(void)
cmdline_idx = 0;
}
+int is_tracing_stopped(void)
+{
+ return trace_stop_count;
+}
+
/**
* ftrace_off_permanent - disable all ftrace code permanently
*
@@ -886,7 +986,7 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
entry->preempt_count = pc & 0xff;
entry->pid = (tsk) ? tsk->pid : 0;
- entry->tgid = (tsk) ? tsk->tgid : 0;
+ entry->lock_depth = (tsk) ? tsk->lock_depth : 0;
entry->flags =
#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
(irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) |
@@ -1068,6 +1168,7 @@ ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc)
return;
entry = ring_buffer_event_data(event);
+ entry->tgid = current->tgid;
memset(&entry->caller, 0, sizeof(entry->caller));
trace.nr_entries = 0;
@@ -1094,6 +1195,7 @@ ftrace_trace_special(void *__tr,
unsigned long arg1, unsigned long arg2, unsigned long arg3,
int pc)
{
+ struct ftrace_event_call *call = &event_special;
struct ring_buffer_event *event;
struct trace_array *tr = __tr;
struct ring_buffer *buffer = tr->buffer;
@@ -1107,7 +1209,9 @@ ftrace_trace_special(void *__tr,
entry->arg1 = arg1;
entry->arg2 = arg2;
entry->arg3 = arg3;
- trace_buffer_unlock_commit(buffer, event, 0, pc);
+
+ if (!filter_check_discard(call, entry, buffer, event))
+ trace_buffer_unlock_commit(buffer, event, 0, pc);
}
void
@@ -1289,7 +1393,7 @@ int trace_array_vprintk(struct trace_array *tr,
int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
{
- return trace_array_printk(&global_trace, ip, fmt, args);
+ return trace_array_vprintk(&global_trace, ip, fmt, args);
}
EXPORT_SYMBOL_GPL(trace_vprintk);
@@ -1530,10 +1634,10 @@ static void print_lat_help_header(struct seq_file *m)
seq_puts(m, "# | / _----=> need-resched \n");
seq_puts(m, "# || / _---=> hardirq/softirq \n");
seq_puts(m, "# ||| / _--=> preempt-depth \n");
- seq_puts(m, "# |||| / \n");
- seq_puts(m, "# ||||| delay \n");
- seq_puts(m, "# cmd pid ||||| time | caller \n");
- seq_puts(m, "# \\ / ||||| \\ | / \n");
+ seq_puts(m, "# |||| /_--=> lock-depth \n");
+ seq_puts(m, "# |||||/ delay \n");
+ seq_puts(m, "# cmd pid |||||| time | caller \n");
+ seq_puts(m, "# \\ / |||||| \\ | / \n");
}
static void print_func_help_header(struct seq_file *m)
@@ -1845,7 +1949,7 @@ static int s_show(struct seq_file *m, void *v)
return 0;
}
-static struct seq_operations tracer_seq_ops = {
+static const struct seq_operations tracer_seq_ops = {
.start = s_start,
.next = s_next,
.stop = s_stop,
@@ -1880,11 +1984,9 @@ __tracing_open(struct inode *inode, struct file *file)
if (current_trace)
*iter->trace = *current_trace;
- if (!alloc_cpumask_var(&iter->started, GFP_KERNEL))
+ if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL))
goto fail;
- cpumask_clear(iter->started);
-
if (current_trace && current_trace->print_max)
iter->tr = &max_tr;
else
@@ -2059,7 +2161,7 @@ static int t_show(struct seq_file *m, void *v)
return 0;
}
-static struct seq_operations show_traces_seq_ops = {
+static const struct seq_operations show_traces_seq_ops = {
.start = t_start,
.next = t_next,
.stop = t_stop,
@@ -2489,7 +2591,7 @@ static ssize_t
tracing_set_trace_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- char buf[max_tracer_type_len+2];
+ char buf[MAX_TRACER_SIZE+2];
int r;
mutex_lock(&trace_types_lock);
@@ -2639,15 +2741,15 @@ static ssize_t
tracing_set_trace_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- char buf[max_tracer_type_len+1];
+ char buf[MAX_TRACER_SIZE+1];
int i;
size_t ret;
int err;
ret = cnt;
- if (cnt > max_tracer_type_len)
- cnt = max_tracer_type_len;
+ if (cnt > MAX_TRACER_SIZE)
+ cnt = MAX_TRACER_SIZE;
if (copy_from_user(&buf, ubuf, cnt))
return -EFAULT;
@@ -4285,7 +4387,7 @@ __init static int tracer_alloc_buffers(void)
if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL))
goto out_free_buffer_mask;
- if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL))
+ if (!zalloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL))
goto out_free_tracing_cpumask;
/* To save memory, keep the ring buffer size to its minimum */
@@ -4296,7 +4398,6 @@ __init static int tracer_alloc_buffers(void)
cpumask_copy(tracing_buffer_mask, cpu_possible_mask);
cpumask_copy(tracing_cpumask, cpu_all_mask);
- cpumask_clear(tracing_reader_cpumask);
/* TODO: make the number of buffers hot pluggable with CPUS */
global_trace.buffer = ring_buffer_alloc(ring_buf_size,