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-rw-r--r--kernel/perf_counter.c1088
1 files changed, 775 insertions, 313 deletions
diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c
index 1a933a221ea..534e20d14d6 100644
--- a/kernel/perf_counter.c
+++ b/kernel/perf_counter.c
@@ -42,6 +42,7 @@ static int perf_overcommit __read_mostly = 1;
static atomic_t nr_counters __read_mostly;
static atomic_t nr_mmap_counters __read_mostly;
static atomic_t nr_comm_counters __read_mostly;
+static atomic_t nr_task_counters __read_mostly;
/*
* perf counter paranoia level:
@@ -87,6 +88,7 @@ void __weak hw_perf_disable(void) { barrier(); }
void __weak hw_perf_enable(void) { barrier(); }
void __weak hw_perf_counter_setup(int cpu) { barrier(); }
+void __weak hw_perf_counter_setup_online(int cpu) { barrier(); }
int __weak
hw_perf_group_sched_in(struct perf_counter *group_leader,
@@ -146,6 +148,28 @@ static void put_ctx(struct perf_counter_context *ctx)
}
}
+static void unclone_ctx(struct perf_counter_context *ctx)
+{
+ if (ctx->parent_ctx) {
+ put_ctx(ctx->parent_ctx);
+ ctx->parent_ctx = NULL;
+ }
+}
+
+/*
+ * If we inherit counters we want to return the parent counter id
+ * to userspace.
+ */
+static u64 primary_counter_id(struct perf_counter *counter)
+{
+ u64 id = counter->id;
+
+ if (counter->parent)
+ id = counter->parent->id;
+
+ return id;
+}
+
/*
* Get the perf_counter_context for a task and lock it.
* This has to cope with with the fact that until it is locked,
@@ -236,6 +260,8 @@ list_add_counter(struct perf_counter *counter, struct perf_counter_context *ctx)
list_add_rcu(&counter->event_entry, &ctx->event_list);
ctx->nr_counters++;
+ if (counter->attr.inherit_stat)
+ ctx->nr_stat++;
}
/*
@@ -250,6 +276,8 @@ list_del_counter(struct perf_counter *counter, struct perf_counter_context *ctx)
if (list_empty(&counter->list_entry))
return;
ctx->nr_counters--;
+ if (counter->attr.inherit_stat)
+ ctx->nr_stat--;
list_del_init(&counter->list_entry);
list_del_rcu(&counter->event_entry);
@@ -279,6 +307,10 @@ counter_sched_out(struct perf_counter *counter,
return;
counter->state = PERF_COUNTER_STATE_INACTIVE;
+ if (counter->pending_disable) {
+ counter->pending_disable = 0;
+ counter->state = PERF_COUNTER_STATE_OFF;
+ }
counter->tstamp_stopped = ctx->time;
counter->pmu->disable(counter);
counter->oncpu = -1;
@@ -1006,6 +1038,81 @@ static int context_equiv(struct perf_counter_context *ctx1,
&& !ctx1->pin_count && !ctx2->pin_count;
}
+static void __perf_counter_read(void *counter);
+
+static void __perf_counter_sync_stat(struct perf_counter *counter,
+ struct perf_counter *next_counter)
+{
+ u64 value;
+
+ if (!counter->attr.inherit_stat)
+ return;
+
+ /*
+ * Update the counter value, we cannot use perf_counter_read()
+ * because we're in the middle of a context switch and have IRQs
+ * disabled, which upsets smp_call_function_single(), however
+ * we know the counter must be on the current CPU, therefore we
+ * don't need to use it.
+ */
+ switch (counter->state) {
+ case PERF_COUNTER_STATE_ACTIVE:
+ __perf_counter_read(counter);
+ break;
+
+ case PERF_COUNTER_STATE_INACTIVE:
+ update_counter_times(counter);
+ break;
+
+ default:
+ break;
+ }
+
+ /*
+ * In order to keep per-task stats reliable we need to flip the counter
+ * values when we flip the contexts.
+ */
+ value = atomic64_read(&next_counter->count);
+ value = atomic64_xchg(&counter->count, value);
+ atomic64_set(&next_counter->count, value);
+
+ swap(counter->total_time_enabled, next_counter->total_time_enabled);
+ swap(counter->total_time_running, next_counter->total_time_running);
+
+ /*
+ * Since we swizzled the values, update the user visible data too.
+ */
+ perf_counter_update_userpage(counter);
+ perf_counter_update_userpage(next_counter);
+}
+
+#define list_next_entry(pos, member) \
+ list_entry(pos->member.next, typeof(*pos), member)
+
+static void perf_counter_sync_stat(struct perf_counter_context *ctx,
+ struct perf_counter_context *next_ctx)
+{
+ struct perf_counter *counter, *next_counter;
+
+ if (!ctx->nr_stat)
+ return;
+
+ counter = list_first_entry(&ctx->event_list,
+ struct perf_counter, event_entry);
+
+ next_counter = list_first_entry(&next_ctx->event_list,
+ struct perf_counter, event_entry);
+
+ while (&counter->event_entry != &ctx->event_list &&
+ &next_counter->event_entry != &next_ctx->event_list) {
+
+ __perf_counter_sync_stat(counter, next_counter);
+
+ counter = list_next_entry(counter, event_entry);
+ next_counter = list_next_entry(next_counter, event_entry);
+ }
+}
+
/*
* Called from scheduler to remove the counters of the current task,
* with interrupts disabled.
@@ -1061,6 +1168,8 @@ void perf_counter_task_sched_out(struct task_struct *task,
ctx->task = next;
next_ctx->task = task;
do_switch = 0;
+
+ perf_counter_sync_stat(ctx, next_ctx);
}
spin_unlock(&next_ctx->lock);
spin_unlock(&ctx->lock);
@@ -1207,7 +1316,6 @@ static void perf_counter_cpu_sched_in(struct perf_cpu_context *cpuctx, int cpu)
#define MAX_INTERRUPTS (~0ULL)
static void perf_log_throttle(struct perf_counter *counter, int enable);
-static void perf_log_period(struct perf_counter *counter, u64 period);
static void perf_adjust_period(struct perf_counter *counter, u64 events)
{
@@ -1226,8 +1334,6 @@ static void perf_adjust_period(struct perf_counter *counter, u64 events)
if (!sample_period)
sample_period = 1;
- perf_log_period(counter, sample_period);
-
hwc->sample_period = sample_period;
}
@@ -1348,9 +1454,54 @@ void perf_counter_task_tick(struct task_struct *curr, int cpu)
}
/*
+ * Enable all of a task's counters that have been marked enable-on-exec.
+ * This expects task == current.
+ */
+static void perf_counter_enable_on_exec(struct task_struct *task)
+{
+ struct perf_counter_context *ctx;
+ struct perf_counter *counter;
+ unsigned long flags;
+ int enabled = 0;
+
+ local_irq_save(flags);
+ ctx = task->perf_counter_ctxp;
+ if (!ctx || !ctx->nr_counters)
+ goto out;
+
+ __perf_counter_task_sched_out(ctx);
+
+ spin_lock(&ctx->lock);
+
+ list_for_each_entry(counter, &ctx->counter_list, list_entry) {
+ if (!counter->attr.enable_on_exec)
+ continue;
+ counter->attr.enable_on_exec = 0;
+ if (counter->state >= PERF_COUNTER_STATE_INACTIVE)
+ continue;
+ counter->state = PERF_COUNTER_STATE_INACTIVE;
+ counter->tstamp_enabled =
+ ctx->time - counter->total_time_enabled;
+ enabled = 1;
+ }
+
+ /*
+ * Unclone this context if we enabled any counter.
+ */
+ if (enabled)
+ unclone_ctx(ctx);
+
+ spin_unlock(&ctx->lock);
+
+ perf_counter_task_sched_in(task, smp_processor_id());
+ out:
+ local_irq_restore(flags);
+}
+
+/*
* Cross CPU call to read the hardware counter
*/
-static void __read(void *info)
+static void __perf_counter_read(void *info)
{
struct perf_counter *counter = info;
struct perf_counter_context *ctx = counter->ctx;
@@ -1372,7 +1523,7 @@ static u64 perf_counter_read(struct perf_counter *counter)
*/
if (counter->state == PERF_COUNTER_STATE_ACTIVE) {
smp_call_function_single(counter->oncpu,
- __read, counter, 1);
+ __perf_counter_read, counter, 1);
} else if (counter->state == PERF_COUNTER_STATE_INACTIVE) {
update_counter_times(counter);
}
@@ -1398,7 +1549,6 @@ __perf_counter_init_context(struct perf_counter_context *ctx,
static struct perf_counter_context *find_get_context(pid_t pid, int cpu)
{
- struct perf_counter_context *parent_ctx;
struct perf_counter_context *ctx;
struct perf_cpu_context *cpuctx;
struct task_struct *task;
@@ -1458,11 +1608,7 @@ static struct perf_counter_context *find_get_context(pid_t pid, int cpu)
retry:
ctx = perf_lock_task_context(task, &flags);
if (ctx) {
- parent_ctx = ctx->parent_ctx;
- if (parent_ctx) {
- put_ctx(parent_ctx);
- ctx->parent_ctx = NULL; /* no longer a clone */
- }
+ unclone_ctx(ctx);
spin_unlock_irqrestore(&ctx->lock, flags);
}
@@ -1508,11 +1654,15 @@ static void free_counter(struct perf_counter *counter)
{
perf_pending_sync(counter);
- atomic_dec(&nr_counters);
- if (counter->attr.mmap)
- atomic_dec(&nr_mmap_counters);
- if (counter->attr.comm)
- atomic_dec(&nr_comm_counters);
+ if (!counter->parent) {
+ atomic_dec(&nr_counters);
+ if (counter->attr.mmap)
+ atomic_dec(&nr_mmap_counters);
+ if (counter->attr.comm)
+ atomic_dec(&nr_comm_counters);
+ if (counter->attr.task)
+ atomic_dec(&nr_task_counters);
+ }
if (counter->destroy)
counter->destroy(counter);
@@ -1546,14 +1696,133 @@ static int perf_release(struct inode *inode, struct file *file)
return 0;
}
+static int perf_counter_read_size(struct perf_counter *counter)
+{
+ int entry = sizeof(u64); /* value */
+ int size = 0;
+ int nr = 1;
+
+ if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
+ size += sizeof(u64);
+
+ if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
+ size += sizeof(u64);
+
+ if (counter->attr.read_format & PERF_FORMAT_ID)
+ entry += sizeof(u64);
+
+ if (counter->attr.read_format & PERF_FORMAT_GROUP) {
+ nr += counter->group_leader->nr_siblings;
+ size += sizeof(u64);
+ }
+
+ size += entry * nr;
+
+ return size;
+}
+
+static u64 perf_counter_read_value(struct perf_counter *counter)
+{
+ struct perf_counter *child;
+ u64 total = 0;
+
+ total += perf_counter_read(counter);
+ list_for_each_entry(child, &counter->child_list, child_list)
+ total += perf_counter_read(child);
+
+ return total;
+}
+
+static int perf_counter_read_entry(struct perf_counter *counter,
+ u64 read_format, char __user *buf)
+{
+ int n = 0, count = 0;
+ u64 values[2];
+
+ values[n++] = perf_counter_read_value(counter);
+ if (read_format & PERF_FORMAT_ID)
+ values[n++] = primary_counter_id(counter);
+
+ count = n * sizeof(u64);
+
+ if (copy_to_user(buf, values, count))
+ return -EFAULT;
+
+ return count;
+}
+
+static int perf_counter_read_group(struct perf_counter *counter,
+ u64 read_format, char __user *buf)
+{
+ struct perf_counter *leader = counter->group_leader, *sub;
+ int n = 0, size = 0, err = -EFAULT;
+ u64 values[3];
+
+ values[n++] = 1 + leader->nr_siblings;
+ if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
+ values[n++] = leader->total_time_enabled +
+ atomic64_read(&leader->child_total_time_enabled);
+ }
+ if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
+ values[n++] = leader->total_time_running +
+ atomic64_read(&leader->child_total_time_running);
+ }
+
+ size = n * sizeof(u64);
+
+ if (copy_to_user(buf, values, size))
+ return -EFAULT;
+
+ err = perf_counter_read_entry(leader, read_format, buf + size);
+ if (err < 0)
+ return err;
+
+ size += err;
+
+ list_for_each_entry(sub, &leader->sibling_list, list_entry) {
+ err = perf_counter_read_entry(counter, read_format,
+ buf + size);
+ if (err < 0)
+ return err;
+
+ size += err;
+ }
+
+ return size;
+}
+
+static int perf_counter_read_one(struct perf_counter *counter,
+ u64 read_format, char __user *buf)
+{
+ u64 values[4];
+ int n = 0;
+
+ values[n++] = perf_counter_read_value(counter);
+ if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
+ values[n++] = counter->total_time_enabled +
+ atomic64_read(&counter->child_total_time_enabled);
+ }
+ if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
+ values[n++] = counter->total_time_running +
+ atomic64_read(&counter->child_total_time_running);
+ }
+ if (read_format & PERF_FORMAT_ID)
+ values[n++] = primary_counter_id(counter);
+
+ if (copy_to_user(buf, values, n * sizeof(u64)))
+ return -EFAULT;
+
+ return n * sizeof(u64);
+}
+
/*
* Read the performance counter - simple non blocking version for now
*/
static ssize_t
perf_read_hw(struct perf_counter *counter, char __user *buf, size_t count)
{
- u64 values[4];
- int n;
+ u64 read_format = counter->attr.read_format;
+ int ret;
/*
* Return end-of-file for a read on a counter that is in
@@ -1563,28 +1832,18 @@ perf_read_hw(struct perf_counter *counter, char __user *buf, size_t count)
if (counter->state == PERF_COUNTER_STATE_ERROR)
return 0;
+ if (count < perf_counter_read_size(counter))
+ return -ENOSPC;
+
WARN_ON_ONCE(counter->ctx->parent_ctx);
mutex_lock(&counter->child_mutex);
- values[0] = perf_counter_read(counter);
- n = 1;
- if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
- values[n++] = counter->total_time_enabled +
- atomic64_read(&counter->child_total_time_enabled);
- if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
- values[n++] = counter->total_time_running +
- atomic64_read(&counter->child_total_time_running);
- if (counter->attr.read_format & PERF_FORMAT_ID)
- values[n++] = counter->id;
+ if (read_format & PERF_FORMAT_GROUP)
+ ret = perf_counter_read_group(counter, read_format, buf);
+ else
+ ret = perf_counter_read_one(counter, read_format, buf);
mutex_unlock(&counter->child_mutex);
- if (count < n * sizeof(u64))
- return -EINVAL;
- count = n * sizeof(u64);
-
- if (copy_to_user(buf, values, count))
- return -EFAULT;
-
- return count;
+ return ret;
}
static ssize_t
@@ -1681,8 +1940,6 @@ static int perf_counter_period(struct perf_counter *counter, u64 __user *arg)
counter->attr.sample_freq = value;
} else {
- perf_log_period(counter, value);
-
counter->attr.sample_period = value;
counter->hw.sample_period = value;
}
@@ -1751,6 +2008,14 @@ int perf_counter_task_disable(void)
return 0;
}
+static int perf_counter_index(struct perf_counter *counter)
+{
+ if (counter->state != PERF_COUNTER_STATE_ACTIVE)
+ return 0;
+
+ return counter->hw.idx + 1 - PERF_COUNTER_INDEX_OFFSET;
+}
+
/*
* Callers need to ensure there can be no nesting of this function, otherwise
* the seqlock logic goes bad. We can not serialize this because the arch
@@ -1775,11 +2040,17 @@ void perf_counter_update_userpage(struct perf_counter *counter)
preempt_disable();
++userpg->lock;
barrier();
- userpg->index = counter->hw.idx;
+ userpg->index = perf_counter_index(counter);
userpg->offset = atomic64_read(&counter->count);
if (counter->state == PERF_COUNTER_STATE_ACTIVE)
userpg->offset -= atomic64_read(&counter->hw.prev_count);
+ userpg->time_enabled = counter->total_time_enabled +
+ atomic64_read(&counter->child_total_time_enabled);
+
+ userpg->time_running = counter->total_time_running +
+ atomic64_read(&counter->child_total_time_running);
+
barrier();
++userpg->lock;
preempt_enable();
@@ -1876,7 +2147,7 @@ fail:
static void perf_mmap_free_page(unsigned long addr)
{
- struct page *page = virt_to_page(addr);
+ struct page *page = virt_to_page((void *)addr);
page->mapping = NULL;
__free_page(page);
@@ -2076,7 +2347,7 @@ static void perf_pending_counter(struct perf_pending_entry *entry)
if (counter->pending_disable) {
counter->pending_disable = 0;
- perf_counter_disable(counter);
+ __perf_counter_disable(counter);
}
if (counter->pending_wakeup) {
@@ -2461,7 +2732,80 @@ static u32 perf_counter_tid(struct perf_counter *counter, struct task_struct *p)
return task_pid_nr_ns(p, counter->ns);
}
-static void perf_counter_output(struct perf_counter *counter, int nmi,
+static void perf_output_read_one(struct perf_output_handle *handle,
+ struct perf_counter *counter)
+{
+ u64 read_format = counter->attr.read_format;
+ u64 values[4];
+ int n = 0;
+
+ values[n++] = atomic64_read(&counter->count);
+ if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
+ values[n++] = counter->total_time_enabled +
+ atomic64_read(&counter->child_total_time_enabled);
+ }
+ if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
+ values[n++] = counter->total_time_running +
+ atomic64_read(&counter->child_total_time_running);
+ }
+ if (read_format & PERF_FORMAT_ID)
+ values[n++] = primary_counter_id(counter);
+
+ perf_output_copy(handle, values, n * sizeof(u64));
+}
+
+/*
+ * XXX PERF_FORMAT_GROUP vs inherited counters seems difficult.
+ */
+static void perf_output_read_group(struct perf_output_handle *handle,
+ struct perf_counter *counter)
+{
+ struct perf_counter *leader = counter->group_leader, *sub;
+ u64 read_format = counter->attr.read_format;
+ u64 values[5];
+ int n = 0;
+
+ values[n++] = 1 + leader->nr_siblings;
+
+ if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
+ values[n++] = leader->total_time_enabled;
+
+ if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
+ values[n++] = leader->total_time_running;
+
+ if (leader != counter)
+ leader->pmu->read(leader);
+
+ values[n++] = atomic64_read(&leader->count);
+ if (read_format & PERF_FORMAT_ID)
+ values[n++] = primary_counter_id(leader);
+
+ perf_output_copy(handle, values, n * sizeof(u64));
+
+ list_for_each_entry(sub, &leader->sibling_list, list_entry) {
+ n = 0;
+
+ if (sub != counter)
+ sub->pmu->read(sub);
+
+ values[n++] = atomic64_read(&sub->count);
+ if (read_format & PERF_FORMAT_ID)
+ values[n++] = primary_counter_id(sub);
+
+ perf_output_copy(handle, values, n * sizeof(u64));
+ }
+}
+
+static void perf_output_read(struct perf_output_handle *handle,
+ struct perf_counter *counter)
+{
+ if (counter->attr.read_format & PERF_FORMAT_GROUP)
+ perf_output_read_group(handle, counter);
+ else
+ perf_output_read_one(handle, counter);
+}
+
+void perf_counter_output(struct perf_counter *counter, int nmi,
struct perf_sample_data *data)
{
int ret;
@@ -2472,10 +2816,6 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,
struct {
u32 pid, tid;
} tid_entry;
- struct {
- u64 id;
- u64 counter;
- } group_entry;
struct perf_callchain_entry *callchain = NULL;
int callchain_size = 0;
u64 time;
@@ -2483,15 +2823,14 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,
u32 cpu, reserved;
} cpu_entry;
- header.type = 0;
+ header.type = PERF_EVENT_SAMPLE;
header.size = sizeof(header);
- header.misc = PERF_EVENT_MISC_OVERFLOW;
+ header.misc = 0;
header.misc |= perf_misc_flags(data->regs);
if (sample_type & PERF_SAMPLE_IP) {
ip = perf_instruction_pointer(data->regs);
- header.type |= PERF_SAMPLE_IP;
header.size += sizeof(ip);
}
@@ -2500,7 +2839,6 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,
tid_entry.pid = perf_counter_pid(counter, current);
tid_entry.tid = perf_counter_tid(counter, current);
- header.type |= PERF_SAMPLE_TID;
header.size += sizeof(tid_entry);
}
@@ -2510,47 +2848,51 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,
*/
time = sched_clock();
- header.type |= PERF_SAMPLE_TIME;
header.size += sizeof(u64);
}
- if (sample_type & PERF_SAMPLE_ADDR) {
- header.type |= PERF_SAMPLE_ADDR;
+ if (sample_type & PERF_SAMPLE_ADDR)
header.size += sizeof(u64);
- }
- if (sample_type & PERF_SAMPLE_ID) {
- header.type |= PERF_SAMPLE_ID;
+ if (sample_type & PERF_SAMPLE_ID)
+ header.size += sizeof(u64);
+
+ if (sample_type & PERF_SAMPLE_STREAM_ID)
header.size += sizeof(u64);
- }
if (sample_type & PERF_SAMPLE_CPU) {
- header.type |= PERF_SAMPLE_CPU;
header.size += sizeof(cpu_entry);
cpu_entry.cpu = raw_smp_processor_id();
+ cpu_entry.reserved = 0;
}
- if (sample_type & PERF_SAMPLE_PERIOD) {
- header.type |= PERF_SAMPLE_PERIOD;
+ if (sample_type & PERF_SAMPLE_PERIOD)
header.size += sizeof(u64);
- }
- if (sample_type & PERF_SAMPLE_GROUP) {
- header.type |= PERF_SAMPLE_GROUP;
- header.size += sizeof(u64) +
- counter->nr_siblings * sizeof(group_entry);
- }
+ if (sample_type & PERF_SAMPLE_READ)
+ header.size += perf_counter_read_size(counter);
if (sample_type & PERF_SAMPLE_CALLCHAIN) {
callchain = perf_callchain(data->regs);
if (callchain) {
callchain_size = (1 + callchain->nr) * sizeof(u64);
-
- header.type |= PERF_SAMPLE_CALLCHAIN;
header.size += callchain_size;
- }
+ } else
+ header.size += sizeof(u64);
+ }
+
+ if (sample_type & PERF_SAMPLE_RAW) {
+ int size = sizeof(u32);
+
+ if (data->raw)
+ size += data->raw->size;
+ else
+ size += sizeof(u32);
+
+ WARN_ON_ONCE(size & (sizeof(u64)-1));
+ header.size += size;
}
ret = perf_output_begin(&handle, counter, header.size, nmi, 1);
@@ -2571,7 +2913,13 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,
if (sample_type & PERF_SAMPLE_ADDR)
perf_output_put(&handle, data->addr);
- if (sample_type & PERF_SAMPLE_ID)
+ if (sample_type & PERF_SAMPLE_ID) {
+ u64 id = primary_counter_id(counter);
+
+ perf_output_put(&handle, id);
+ }
+
+ if (sample_type & PERF_SAMPLE_STREAM_ID)
perf_output_put(&handle, counter->id);
if (sample_type & PERF_SAMPLE_CPU)
@@ -2580,76 +2928,125 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,
if (sample_type & PERF_SAMPLE_PERIOD)
perf_output_put(&handle, data->period);
- /*
- * XXX PERF_SAMPLE_GROUP vs inherited counters seems difficult.
- */
- if (sample_type & PERF_SAMPLE_GROUP) {
- struct perf_counter *leader, *sub;
- u64 nr = counter->nr_siblings;
+ if (sample_type & PERF_SAMPLE_READ)
+ perf_output_read(&handle, counter);
- perf_output_put(&handle, nr);
-
- leader = counter->group_leader;
- list_for_each_entry(sub, &leader->sibling_list, list_entry) {
- if (sub != counter)
- sub->pmu->read(sub);
-
- group_entry.id = sub->id;
- group_entry.counter = atomic64_read(&sub->count);
+ if (sample_type & PERF_SAMPLE_CALLCHAIN) {
+ if (callchain)
+ perf_output_copy(&handle, callchain, callchain_size);
+ else {
+ u64 nr = 0;
+ perf_output_put(&handle, nr);
+ }
+ }
- perf_output_put(&handle, group_entry);
+ if (sample_type & PERF_SAMPLE_RAW) {
+ if (data->raw) {
+ perf_output_put(&handle, data->raw->size);
+ perf_output_copy(&handle, data->raw->data, data->raw->size);
+ } else {
+ struct {
+ u32 size;
+ u32 data;
+ } raw = {
+ .size = sizeof(u32),
+ .data = 0,
+ };
+ perf_output_put(&handle, raw);
}
}
- if (callchain)
- perf_output_copy(&handle, callchain, callchain_size);
+ perf_output_end(&handle);
+}
+
+/*
+ * read event
+ */
+
+struct perf_read_event {
+ struct perf_event_header header;
+
+ u32 pid;
+ u32 tid;
+};
+
+static void
+perf_counter_read_event(struct perf_counter *counter,
+ struct task_struct *task)
+{
+ struct perf_output_handle handle;
+ struct perf_read_event event = {
+ .header = {
+ .type = PERF_EVENT_READ,
+ .misc = 0,
+ .size = sizeof(event) + perf_counter_read_size(counter),
+ },
+ .pid = perf_counter_pid(counter, task),
+ .tid = perf_counter_tid(counter, task),
+ };
+ int ret;
+
+ ret = perf_output_begin(&handle, counter, event.header.size, 0, 0);
+ if (ret)
+ return;
+
+ perf_output_put(&handle, event);
+ perf_output_read(&handle, counter);
perf_output_end(&handle);
}
/*
- * fork tracking
+ * task tracking -- fork/exit
+ *
+ * enabled by: attr.comm | attr.mmap | attr.task
*/
-struct perf_fork_event {
- struct task_struct *task;
+struct perf_task_event {
+ struct task_struct *task;
+ struct perf_counter_context *task_ctx;
struct {
struct perf_event_header header;
u32 pid;
u32 ppid;
+ u32 tid;
+ u32 ptid;
} event;
};
-static void perf_counter_fork_output(struct perf_counter *counter,
- struct perf_fork_event *fork_event)
+static void perf_counter_task_output(struct perf_counter *counter,
+ struct perf_task_event *task_event)
{
struct perf_output_handle handle;
- int size = fork_event->event.header.size;
- struct task_struct *task = fork_event->task;
+ int size = task_event->event.header.size;
+ struct task_struct *task = task_event->task;
int ret = perf_output_begin(&handle, counter, size, 0, 0);
if (ret)
return;
- fork_event->event.pid = perf_counter_pid(counter, task);
- fork_event->event.ppid = perf_counter_pid(counter, task->real_parent);
+ task_event->event.pid = perf_counter_pid(counter, task);
+ task_event->event.ppid = perf_counter_pid(counter, current);
+
+ task_event->event.tid = perf_counter_tid(counter, task);
+ task_event->event.ptid = perf_counter_tid(counter, current);
- perf_output_put(&handle, fork_event->event);
+ perf_output_put(&handle, task_event->event);
perf_output_end(&handle);
}
-static int perf_counter_fork_match(struct perf_counter *counter)
+static int perf_counter_task_match(struct perf_counter *counter)
{
- if (counter->attr.comm || counter->attr.mmap)
+ if (counter->attr.comm || counter->attr.mmap || counter->attr.task)
return 1;
return 0;
}
-static void perf_counter_fork_ctx(struct perf_counter_context *ctx,
- struct perf_fork_event *fork_event)
+static void perf_counter_task_ctx(struct perf_counter_context *ctx,
+ struct perf_task_event *task_event)
{
struct perf_counter *counter;
@@ -2658,51 +3055,62 @@ static void perf_counter_fork_ctx(struct perf_counter_context *ctx,
rcu_read_lock();
list_for_each_entry_rcu(counter, &ctx->event_list, event_entry) {
- if (perf_counter_fork_match(counter))
- perf_counter_fork_output(counter, fork_event);
+ if (perf_counter_task_match(counter))
+ perf_counter_task_output(counter, task_event);
}
rcu_read_unlock();
}
-static void perf_counter_fork_event(struct perf_fork_event *fork_event)
+static void perf_counter_task_event(struct perf_task_event *task_event)
{
struct perf_cpu_context *cpuctx;
- struct perf_counter_context *ctx;
+ struct perf_counter_context *ctx = task_event->task_ctx;
cpuctx = &get_cpu_var(perf_cpu_context);
- perf_counter_fork_ctx(&cpuctx->ctx, fork_event);
+ perf_counter_task_ctx(&cpuctx->ctx, task_event);
put_cpu_var(perf_cpu_context);
rcu_read_lock();
- /*
- * doesn't really matter which of the child contexts the
- * events ends up in.
- */
- ctx = rcu_dereference(current->perf_counter_ctxp);
+ if (!ctx)
+ ctx = rcu_dereference(task_event->task->perf_counter_ctxp);
if (ctx)
- perf_counter_fork_ctx(ctx, fork_event);
+ perf_counter_task_ctx(ctx, task_event);
rcu_read_unlock();
}
-void perf_counter_fork(struct task_struct *task)
+static void perf_counter_task(struct task_struct *task,
+ struct perf_counter_context *task_ctx,
+ int new)
{
- struct perf_fork_event fork_event;
+ struct perf_task_event task_event;
if (!atomic_read(&nr_comm_counters) &&
- !atomic_read(&nr_mmap_counters))
+ !atomic_read(&nr_mmap_counters) &&
+ !atomic_read(&nr_task_counters))
return;
- fork_event = (struct perf_fork_event){
- .task = task,
- .event = {
+ task_event = (struct perf_task_event){
+ .task = task,
+ .task_ctx = task_ctx,
+ .event = {
.header = {
- .type = PERF_EVENT_FORK,
- .size = sizeof(fork_event.event),
+ .type = new ? PERF_EVENT_FORK : PERF_EVENT_EXIT,
+ .misc = 0,
+ .size = sizeof(task_event.event),
},
+ /* .pid */
+ /* .ppid */
+ /* .tid */
+ /* .ptid */
},
};
- perf_counter_fork_event(&fork_event);
+ perf_counter_task_event(&task_event);
+}
+
+void perf_counter_fork(struct task_struct *task)
+{
+ perf_counter_task(task, NULL, 1);
}
/*
@@ -2770,8 +3178,10 @@ static void perf_counter_comm_event(struct perf_comm_event *comm_event)
struct perf_cpu_context *cpuctx;
struct perf_counter_context *ctx;
unsigned int size;
- char *comm = comm_event->task->comm;
+ char comm[TASK_COMM_LEN];
+ memset(comm, 0, sizeof(comm));
+ strncpy(comm, comm_event->task->comm, sizeof(comm));
size = ALIGN(strlen(comm)+1, sizeof(u64));
comm_event->comm = comm;
@@ -2798,13 +3208,24 @@ void perf_counter_comm(struct task_struct *task)
{
struct perf_comm_event comm_event;
+ if (task->perf_counter_ctxp)
+ perf_counter_enable_on_exec(task);
+
if (!atomic_read(&nr_comm_counters))
return;
comm_event = (struct perf_comm_event){
.task = task,
+ /* .comm */
+ /* .comm_size */
.event = {
- .header = { .type = PERF_EVENT_COMM, },
+ .header = {
+ .type = PERF_EVENT_COMM,
+ .misc = 0,
+ /* .size */
+ },
+ /* .pid */
+ /* .tid */
},
};
@@ -2887,8 +3308,15 @@ static void perf_counter_mmap_event(struct perf_mmap_event *mmap_event)
char *buf = NULL;
const char *name;
+ memset(tmp, 0, sizeof(tmp));
+
if (file) {
- buf = kzalloc(PATH_MAX, GFP_KERNEL);
+ /*
+ * d_path works from the end of the buffer backwards, so we
+ * need to add enough zero bytes after the string to handle
+ * the 64bit alignment we do later.
+ */
+ buf = kzalloc(PATH_MAX + sizeof(u64), GFP_KERNEL);
if (!buf) {
name = strncpy(tmp, "//enomem", sizeof(tmp));
goto got_name;
@@ -2899,9 +3327,11 @@ static void perf_counter_mmap_event(struct perf_mmap_event *mmap_event)
goto got_name;
}
} else {
- name = arch_vma_name(mmap_event->vma);
- if (name)
+ if (arch_vma_name(mmap_event->vma)) {
+ name = strncpy(tmp, arch_vma_name(mmap_event->vma),
+ sizeof(tmp));
goto got_name;
+ }
if (!vma->vm_mm) {
name = strncpy(tmp, "[vdso]", sizeof(tmp));
@@ -2946,8 +3376,16 @@ void __perf_counter_mmap(struct vm_area_struct *vma)
mmap_event = (struct perf_mmap_event){
.vma = vma,
+ /* .file_name */
+ /* .file_size */
.event = {
- .header = { .type = PERF_EVENT_MMAP, },
+ .header = {
+ .type = PERF_EVENT_MMAP,
+ .misc = 0,
+ /* .size */
+ },
+ /* .pid */
+ /* .tid */
.start = vma->vm_start,
.len = vma->vm_end - vma->vm_start,
.pgoff = vma->vm_pgoff,
@@ -2958,49 +3396,6 @@ void __perf_counter_mmap(struct vm_area_struct *vma)
}
/*
- * Log sample_period changes so that analyzing tools can re-normalize the
- * event flow.
- */
-
-struct freq_event {
- struct perf_event_header header;
- u64 time;
- u64 id;
- u64 period;
-};
-
-static void perf_log_period(struct perf_counter *counter, u64 period)
-{
- struct perf_output_handle handle;
- struct freq_event event;
- int ret;
-
- if (counter->hw.sample_period == period)
- return;
-
- if (counter->attr.sample_type & PERF_SAMPLE_PERIOD)
- return;
-
- event = (struct freq_event) {
- .header = {
- .type = PERF_EVENT_PERIOD,
- .misc = 0,
- .size = sizeof(event),
- },
- .time = sched_clock(),
- .id = counter->id,
- .period = period,
- };
-
- ret = perf_output_begin(&handle, counter, sizeof(event), 1, 0);
- if (ret)
- return;
-
- perf_output_put(&handle, event);
- perf_output_end(&handle);
-}
-
-/*
* IRQ throttle logging
*/
@@ -3013,16 +3408,21 @@ static void perf_log_throttle(struct perf_counter *counter, int enable)
struct perf_event_header header;
u64 time;
u64 id;
+ u64 stream_id;
} throttle_event = {
.header = {
- .type = PERF_EVENT_THROTTLE + 1,
+ .type = PERF_EVENT_THROTTLE,
.misc = 0,
.size = sizeof(throttle_event),
},
- .time = sched_clock(),
- .id = counter->id,
+ .time = sched_clock(),
+ .id = primary_counter_id(counter),
+ .stream_id = counter->id,
};
+ if (enable)
+ throttle_event.header.type = PERF_EVENT_UNTHROTTLE;
+
ret = perf_output_begin(&handle, counter, sizeof(throttle_event), 1, 0);
if (ret)
return;
@@ -3099,125 +3499,111 @@ int perf_counter_overflow(struct perf_counter *counter, int nmi,
* Generic software counter infrastructure
*/
-static void perf_swcounter_update(struct perf_counter *counter)
+/*
+ * We directly increment counter->count and keep a second value in
+ * counter->hw.period_left to count intervals. This period counter
+ * is kept in the range [-sample_period, 0] so that we can use the
+ * sign as trigger.
+ */
+
+static u64 perf_swcounter_set_period(struct perf_counter *counter)
{
struct hw_perf_counter *hwc = &counter->hw;
- u64 prev, now;
- s64 delta;
+ u64 period = hwc->last_period;
+ u64 nr, offset;
+ s64 old, val;
+
+ hwc->last_period = hwc->sample_period;
again:
- prev = atomic64_read(&hwc->prev_count);
- now = atomic64_read(&hwc->count);
- if (atomic64_cmpxchg(&hwc->prev_count, prev, now) != prev)
- goto again;
+ old = val = atomic64_read(&hwc->period_left);
+ if (val < 0)
+ return 0;
- delta = now - prev;
+ nr = div64_u64(period + val, period);
+ offset = nr * period;
+ val -= offset;
+ if (atomic64_cmpxchg(&hwc->period_left, old, val) != old)
+ goto again;
- atomic64_add(delta, &counter->count);
- atomic64_sub(delta, &hwc->period_left);
+ return nr;
}
-static void perf_swcounter_set_period(struct perf_counter *counter)
+static void perf_swcounter_overflow(struct perf_counter *counter,
+ int nmi, struct perf_sample_data *data)
{
struct hw_perf_counter *hwc = &counter->hw;
- s64 left = atomic64_read(&hwc->period_left);
- s64 period = hwc->sample_period;
+ u64 overflow;
- if (unlikely(left <= -period)) {
- left = period;
- atomic64_set(&hwc->period_left, left);
- hwc->last_period = period;
- }
+ data->period = counter->hw.last_