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-rw-r--r--kernel/events/Makefile2
-rw-r--r--kernel/events/callchain.c191
-rw-r--r--kernel/events/core.c218
-rw-r--r--kernel/events/internal.h39
4 files changed, 238 insertions, 212 deletions
diff --git a/kernel/events/Makefile b/kernel/events/Makefile
index 89e5e8aa4c36..22d901f9caf4 100644
--- a/kernel/events/Makefile
+++ b/kernel/events/Makefile
@@ -2,5 +2,5 @@ ifdef CONFIG_FUNCTION_TRACER
CFLAGS_REMOVE_core.o = -pg
endif
-obj-y := core.o ring_buffer.o
+obj-y := core.o ring_buffer.o callchain.o
obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o
diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c
new file mode 100644
index 000000000000..057e24b665cf
--- /dev/null
+++ b/kernel/events/callchain.c
@@ -0,0 +1,191 @@
+/*
+ * Performance events callchain code, extracted from core.c:
+ *
+ * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de>
+ * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar
+ * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
+ *
+ * For licensing details see kernel-base/COPYING
+ */
+
+#include <linux/perf_event.h>
+#include <linux/slab.h>
+#include "internal.h"
+
+struct callchain_cpus_entries {
+ struct rcu_head rcu_head;
+ struct perf_callchain_entry *cpu_entries[0];
+};
+
+static DEFINE_PER_CPU(int, callchain_recursion[PERF_NR_CONTEXTS]);
+static atomic_t nr_callchain_events;
+static DEFINE_MUTEX(callchain_mutex);
+static struct callchain_cpus_entries *callchain_cpus_entries;
+
+
+__weak void perf_callchain_kernel(struct perf_callchain_entry *entry,
+ struct pt_regs *regs)
+{
+}
+
+__weak void perf_callchain_user(struct perf_callchain_entry *entry,
+ struct pt_regs *regs)
+{
+}
+
+static void release_callchain_buffers_rcu(struct rcu_head *head)
+{
+ struct callchain_cpus_entries *entries;
+ int cpu;
+
+ entries = container_of(head, struct callchain_cpus_entries, rcu_head);
+
+ for_each_possible_cpu(cpu)
+ kfree(entries->cpu_entries[cpu]);
+
+ kfree(entries);
+}
+
+static void release_callchain_buffers(void)
+{
+ struct callchain_cpus_entries *entries;
+
+ entries = callchain_cpus_entries;
+ rcu_assign_pointer(callchain_cpus_entries, NULL);
+ call_rcu(&entries->rcu_head, release_callchain_buffers_rcu);
+}
+
+static int alloc_callchain_buffers(void)
+{
+ int cpu;
+ int size;
+ struct callchain_cpus_entries *entries;
+
+ /*
+ * We can't use the percpu allocation API for data that can be
+ * accessed from NMI. Use a temporary manual per cpu allocation
+ * until that gets sorted out.
+ */
+ size = offsetof(struct callchain_cpus_entries, cpu_entries[nr_cpu_ids]);
+
+ entries = kzalloc(size, GFP_KERNEL);
+ if (!entries)
+ return -ENOMEM;
+
+ size = sizeof(struct perf_callchain_entry) * PERF_NR_CONTEXTS;
+
+ for_each_possible_cpu(cpu) {
+ entries->cpu_entries[cpu] = kmalloc_node(size, GFP_KERNEL,
+ cpu_to_node(cpu));
+ if (!entries->cpu_entries[cpu])
+ goto fail;
+ }
+
+ rcu_assign_pointer(callchain_cpus_entries, entries);
+
+ return 0;
+
+fail:
+ for_each_possible_cpu(cpu)
+ kfree(entries->cpu_entries[cpu]);
+ kfree(entries);
+
+ return -ENOMEM;
+}
+
+int get_callchain_buffers(void)
+{
+ int err = 0;
+ int count;
+
+ mutex_lock(&callchain_mutex);
+
+ count = atomic_inc_return(&nr_callchain_events);
+ if (WARN_ON_ONCE(count < 1)) {
+ err = -EINVAL;
+ goto exit;
+ }
+
+ if (count > 1) {
+ /* If the allocation failed, give up */
+ if (!callchain_cpus_entries)
+ err = -ENOMEM;
+ goto exit;
+ }
+
+ err = alloc_callchain_buffers();
+ if (err)
+ release_callchain_buffers();
+exit:
+ mutex_unlock(&callchain_mutex);
+
+ return err;
+}
+
+void put_callchain_buffers(void)
+{
+ if (atomic_dec_and_mutex_lock(&nr_callchain_events, &callchain_mutex)) {
+ release_callchain_buffers();
+ mutex_unlock(&callchain_mutex);
+ }
+}
+
+static struct perf_callchain_entry *get_callchain_entry(int *rctx)
+{
+ int cpu;
+ struct callchain_cpus_entries *entries;
+
+ *rctx = get_recursion_context(__get_cpu_var(callchain_recursion));
+ if (*rctx == -1)
+ return NULL;
+
+ entries = rcu_dereference(callchain_cpus_entries);
+ if (!entries)
+ return NULL;
+
+ cpu = smp_processor_id();
+
+ return &entries->cpu_entries[cpu][*rctx];
+}
+
+static void
+put_callchain_entry(int rctx)
+{
+ put_recursion_context(__get_cpu_var(callchain_recursion), rctx);
+}
+
+struct perf_callchain_entry *perf_callchain(struct pt_regs *regs)
+{
+ int rctx;
+ struct perf_callchain_entry *entry;
+
+
+ entry = get_callchain_entry(&rctx);
+ if (rctx == -1)
+ return NULL;
+
+ if (!entry)
+ goto exit_put;
+
+ entry->nr = 0;
+
+ if (!user_mode(regs)) {
+ perf_callchain_store(entry, PERF_CONTEXT_KERNEL);
+ perf_callchain_kernel(entry, regs);
+ if (current->mm)
+ regs = task_pt_regs(current);
+ else
+ regs = NULL;
+ }
+
+ if (regs) {
+ perf_callchain_store(entry, PERF_CONTEXT_USER);
+ perf_callchain_user(entry, regs);
+ }
+
+exit_put:
+ put_callchain_entry(rctx);
+
+ return entry;
+}
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 600c1629b64d..a355ffb0b28f 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -1325,6 +1325,7 @@ retry:
}
raw_spin_unlock_irq(&ctx->lock);
}
+EXPORT_SYMBOL_GPL(perf_event_disable);
static void perf_set_shadow_time(struct perf_event *event,
struct perf_event_context *ctx,
@@ -1809,6 +1810,7 @@ retry:
out:
raw_spin_unlock_irq(&ctx->lock);
}
+EXPORT_SYMBOL_GPL(perf_event_enable);
int perf_event_refresh(struct perf_event *event, int refresh)
{
@@ -2574,215 +2576,6 @@ static u64 perf_event_read(struct perf_event *event)
}
/*
- * Callchain support
- */
-
-struct callchain_cpus_entries {
- struct rcu_head rcu_head;
- struct perf_callchain_entry *cpu_entries[0];
-};
-
-static DEFINE_PER_CPU(int, callchain_recursion[PERF_NR_CONTEXTS]);
-static atomic_t nr_callchain_events;
-static DEFINE_MUTEX(callchain_mutex);
-struct callchain_cpus_entries *callchain_cpus_entries;
-
-
-__weak void perf_callchain_kernel(struct perf_callchain_entry *entry,
- struct pt_regs *regs)
-{
-}
-
-__weak void perf_callchain_user(struct perf_callchain_entry *entry,
- struct pt_regs *regs)
-{
-}
-
-static void release_callchain_buffers_rcu(struct rcu_head *head)
-{
- struct callchain_cpus_entries *entries;
- int cpu;
-
- entries = container_of(head, struct callchain_cpus_entries, rcu_head);
-
- for_each_possible_cpu(cpu)
- kfree(entries->cpu_entries[cpu]);
-
- kfree(entries);
-}
-
-static void release_callchain_buffers(void)
-{
- struct callchain_cpus_entries *entries;
-
- entries = callchain_cpus_entries;
- rcu_assign_pointer(callchain_cpus_entries, NULL);
- call_rcu(&entries->rcu_head, release_callchain_buffers_rcu);
-}
-
-static int alloc_callchain_buffers(void)
-{
- int cpu;
- int size;
- struct callchain_cpus_entries *entries;
-
- /*
- * We can't use the percpu allocation API for data that can be
- * accessed from NMI. Use a temporary manual per cpu allocation
- * until that gets sorted out.
- */
- size = offsetof(struct callchain_cpus_entries, cpu_entries[nr_cpu_ids]);
-
- entries = kzalloc(size, GFP_KERNEL);
- if (!entries)
- return -ENOMEM;
-
- size = sizeof(struct perf_callchain_entry) * PERF_NR_CONTEXTS;
-
- for_each_possible_cpu(cpu) {
- entries->cpu_entries[cpu] = kmalloc_node(size, GFP_KERNEL,
- cpu_to_node(cpu));
- if (!entries->cpu_entries[cpu])
- goto fail;
- }
-
- rcu_assign_pointer(callchain_cpus_entries, entries);
-
- return 0;
-
-fail:
- for_each_possible_cpu(cpu)
- kfree(entries->cpu_entries[cpu]);
- kfree(entries);
-
- return -ENOMEM;
-}
-
-static int get_callchain_buffers(void)
-{
- int err = 0;
- int count;
-
- mutex_lock(&callchain_mutex);
-
- count = atomic_inc_return(&nr_callchain_events);
- if (WARN_ON_ONCE(count < 1)) {
- err = -EINVAL;
- goto exit;
- }
-
- if (count > 1) {
- /* If the allocation failed, give up */
- if (!callchain_cpus_entries)
- err = -ENOMEM;
- goto exit;
- }
-
- err = alloc_callchain_buffers();
- if (err)
- release_callchain_buffers();
-exit:
- mutex_unlock(&callchain_mutex);
-
- return err;
-}
-
-static void put_callchain_buffers(void)
-{
- if (atomic_dec_and_mutex_lock(&nr_callchain_events, &callchain_mutex)) {
- release_callchain_buffers();
- mutex_unlock(&callchain_mutex);
- }
-}
-
-static int get_recursion_context(int *recursion)
-{
- int rctx;
-
- if (in_nmi())
- rctx = 3;
- else if (in_irq())
- rctx = 2;
- else if (in_softirq())
- rctx = 1;
- else
- rctx = 0;
-
- if (recursion[rctx])
- return -1;
-
- recursion[rctx]++;
- barrier();
-
- return rctx;
-}
-
-static inline void put_recursion_context(int *recursion, int rctx)
-{
- barrier();
- recursion[rctx]--;
-}
-
-static struct perf_callchain_entry *get_callchain_entry(int *rctx)
-{
- int cpu;
- struct callchain_cpus_entries *entries;
-
- *rctx = get_recursion_context(__get_cpu_var(callchain_recursion));
- if (*rctx == -1)
- return NULL;
-
- entries = rcu_dereference(callchain_cpus_entries);
- if (!entries)
- return NULL;
-
- cpu = smp_processor_id();
-
- return &entries->cpu_entries[cpu][*rctx];
-}
-
-static void
-put_callchain_entry(int rctx)
-{
- put_recursion_context(__get_cpu_var(callchain_recursion), rctx);
-}
-
-static struct perf_callchain_entry *perf_callchain(struct pt_regs *regs)
-{
- int rctx;
- struct perf_callchain_entry *entry;
-
-
- entry = get_callchain_entry(&rctx);
- if (rctx == -1)
- return NULL;
-
- if (!entry)
- goto exit_put;
-
- entry->nr = 0;
-
- if (!user_mode(regs)) {
- perf_callchain_store(entry, PERF_CONTEXT_KERNEL);
- perf_callchain_kernel(entry, regs);
- if (current->mm)
- regs = task_pt_regs(current);
- else
- regs = NULL;
- }
-
- if (regs) {
- perf_callchain_store(entry, PERF_CONTEXT_USER);
- perf_callchain_user(entry, regs);
- }
-
-exit_put:
- put_callchain_entry(rctx);
-
- return entry;
-}
-
-/*
* Initialize the perf_event context in a task_struct:
*/
static void __perf_event_init_context(struct perf_event_context *ctx)
@@ -4816,7 +4609,6 @@ static void perf_swevent_overflow(struct perf_event *event, u64 overflow,
struct hw_perf_event *hwc = &event->hw;
int throttle = 0;
- data->period = event->hw.last_period;
if (!overflow)
overflow = perf_swevent_set_period(event);
@@ -4850,6 +4642,12 @@ static void perf_swevent_event(struct perf_event *event, u64 nr,
if (!is_sampling_event(event))
return;
+ if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) {
+ data->period = nr;
+ return perf_swevent_overflow(event, 1, data, regs);
+ } else
+ data->period = event->hw.last_period;
+
if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq)
return perf_swevent_overflow(event, 1, data, regs);
diff --git a/kernel/events/internal.h b/kernel/events/internal.h
index 64568a699375..b0b107f90afc 100644
--- a/kernel/events/internal.h
+++ b/kernel/events/internal.h
@@ -1,6 +1,10 @@
#ifndef _KERNEL_EVENTS_INTERNAL_H
#define _KERNEL_EVENTS_INTERNAL_H
+#include <linux/hardirq.h>
+
+/* Buffer handling */
+
#define RING_BUFFER_WRITABLE 0x01
struct ring_buffer {
@@ -67,7 +71,7 @@ static inline int page_order(struct ring_buffer *rb)
}
#endif
-static unsigned long perf_data_size(struct ring_buffer *rb)
+static inline unsigned long perf_data_size(struct ring_buffer *rb)
{
return rb->nr_pages << (PAGE_SHIFT + page_order(rb));
}
@@ -96,4 +100,37 @@ __output_copy(struct perf_output_handle *handle,
} while (len);
}
+/* Callchain handling */
+extern struct perf_callchain_entry *perf_callchain(struct pt_regs *regs);
+extern int get_callchain_buffers(void);
+extern void put_callchain_buffers(void);
+
+static inline int get_recursion_context(int *recursion)
+{
+ int rctx;
+
+ if (in_nmi())
+ rctx = 3;
+ else if (in_irq())
+ rctx = 2;
+ else if (in_softirq())
+ rctx = 1;
+ else
+ rctx = 0;
+
+ if (recursion[rctx])
+ return -1;
+
+ recursion[rctx]++;
+ barrier();
+
+ return rctx;
+}
+
+static inline void put_recursion_context(int *recursion, int rctx)
+{
+ barrier();
+ recursion[rctx]--;
+}
+
#endif /* _KERNEL_EVENTS_INTERNAL_H */
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-11-14 04:40:42 +0100