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perf: Factor out auxiliary events notification
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Add perf_event_aux() function to send out all types of
auxiliary events - mmap, task, comm events. For each type
there's match and output functions defined and used as
callbacks during perf_event_aux processing.

This way we can centralize the pmu/context iterating and
event matching logic. Also since lot of the code was
duplicated, this patch reduces the .text size about 2kB
on my setup:

  snipped output from 'objdump -x kernel/events/core.o'

  before:
  Idx Name          Size
    0 .text         0000d313

  after:
  Idx Name          Size
    0 .text         0000cad3

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/1367857638-27631-3-git-send-email-jolsa@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Jiri Olsa authored and Ingo Molnar committed May 7, 2013
1 parent 524eff1 commit 52d857a
Showing 1 changed file with 89 additions and 153 deletions.
242 changes: 89 additions & 153 deletions kernel/events/core.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -4394,6 +4394,64 @@ perf_event_read_event(struct perf_event *event,
perf_output_end(&handle);
}

typedef int (perf_event_aux_match_cb)(struct perf_event *event, void *data);
typedef void (perf_event_aux_output_cb)(struct perf_event *event, void *data);

static void
perf_event_aux_ctx(struct perf_event_context *ctx,
perf_event_aux_match_cb match,
perf_event_aux_output_cb output,
void *data)
{
struct perf_event *event;

list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
if (event->state < PERF_EVENT_STATE_INACTIVE)
continue;
if (!event_filter_match(event))
continue;
if (match(event, data))
output(event, data);
}
}

static void
perf_event_aux(perf_event_aux_match_cb match,
perf_event_aux_output_cb output,
void *data,
struct perf_event_context *task_ctx)
{
struct perf_cpu_context *cpuctx;
struct perf_event_context *ctx;
struct pmu *pmu;
int ctxn;

rcu_read_lock();
list_for_each_entry_rcu(pmu, &pmus, entry) {
cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
if (cpuctx->unique_pmu != pmu)
goto next;
perf_event_aux_ctx(&cpuctx->ctx, match, output, data);
if (task_ctx)
goto next;
ctxn = pmu->task_ctx_nr;
if (ctxn < 0)
goto next;
ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
if (ctx)
perf_event_aux_ctx(ctx, match, output, data);
next:
put_cpu_ptr(pmu->pmu_cpu_context);
}

if (task_ctx) {
preempt_disable();
perf_event_aux_ctx(task_ctx, match, output, data);
preempt_enable();
}
rcu_read_unlock();
}

/*
* task tracking -- fork/exit
*
Expand All @@ -4416,8 +4474,9 @@ struct perf_task_event {
};

static void perf_event_task_output(struct perf_event *event,
struct perf_task_event *task_event)
void *data)
{
struct perf_task_event *task_event = data;
struct perf_output_handle handle;
struct perf_sample_data sample;
struct task_struct *task = task_event->task;
Expand Down Expand Up @@ -4445,64 +4504,11 @@ static void perf_event_task_output(struct perf_event *event,
task_event->event_id.header.size = size;
}

static int perf_event_task_match(struct perf_event *event)
{
if (event->state < PERF_EVENT_STATE_INACTIVE)
return 0;

if (!event_filter_match(event))
return 0;

if (event->attr.comm || event->attr.mmap ||
event->attr.mmap_data || event->attr.task)
return 1;

return 0;
}

static void perf_event_task_ctx(struct perf_event_context *ctx,
struct perf_task_event *task_event)
{
struct perf_event *event;

list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
if (perf_event_task_match(event))
perf_event_task_output(event, task_event);
}
}

static void perf_event_task_event(struct perf_task_event *task_event)
static int perf_event_task_match(struct perf_event *event,
void *data __maybe_unused)
{
struct perf_cpu_context *cpuctx;
struct perf_event_context *ctx, *task_ctx = task_event->task_ctx;
struct pmu *pmu;
int ctxn;

rcu_read_lock();
list_for_each_entry_rcu(pmu, &pmus, entry) {
cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
if (cpuctx->unique_pmu != pmu)
goto next;
perf_event_task_ctx(&cpuctx->ctx, task_event);

if (task_ctx)
goto next;
ctxn = pmu->task_ctx_nr;
if (ctxn < 0)
goto next;
ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
if (ctx)
perf_event_task_ctx(ctx, task_event);
next:
put_cpu_ptr(pmu->pmu_cpu_context);
}
if (task_ctx) {
preempt_disable();
perf_event_task_ctx(task_ctx, task_event);
preempt_enable();
}

rcu_read_unlock();
return event->attr.comm || event->attr.mmap ||
event->attr.mmap_data || event->attr.task;
}

static void perf_event_task(struct task_struct *task,
Expand Down Expand Up @@ -4533,7 +4539,10 @@ static void perf_event_task(struct task_struct *task,
},
};

perf_event_task_event(&task_event);
perf_event_aux(perf_event_task_match,
perf_event_task_output,
&task_event,
task_ctx);
}

void perf_event_fork(struct task_struct *task)
Expand All @@ -4559,8 +4568,9 @@ struct perf_comm_event {
};

static void perf_event_comm_output(struct perf_event *event,
struct perf_comm_event *comm_event)
void *data)
{
struct perf_comm_event *comm_event = data;
struct perf_output_handle handle;
struct perf_sample_data sample;
int size = comm_event->event_id.header.size;
Expand All @@ -4587,39 +4597,16 @@ static void perf_event_comm_output(struct perf_event *event,
comm_event->event_id.header.size = size;
}

static int perf_event_comm_match(struct perf_event *event)
{
if (event->state < PERF_EVENT_STATE_INACTIVE)
return 0;

if (!event_filter_match(event))
return 0;

if (event->attr.comm)
return 1;

return 0;
}

static void perf_event_comm_ctx(struct perf_event_context *ctx,
struct perf_comm_event *comm_event)
static int perf_event_comm_match(struct perf_event *event,
void *data __maybe_unused)
{
struct perf_event *event;

list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
if (perf_event_comm_match(event))
perf_event_comm_output(event, comm_event);
}
return event->attr.comm;
}

static void perf_event_comm_event(struct perf_comm_event *comm_event)
{
struct perf_cpu_context *cpuctx;
struct perf_event_context *ctx;
char comm[TASK_COMM_LEN];
unsigned int size;
struct pmu *pmu;
int ctxn;

memset(comm, 0, sizeof(comm));
strlcpy(comm, comm_event->task->comm, sizeof(comm));
Expand All @@ -4629,24 +4616,11 @@ static void perf_event_comm_event(struct perf_comm_event *comm_event)
comm_event->comm_size = size;

comm_event->event_id.header.size = sizeof(comm_event->event_id) + size;
rcu_read_lock();
list_for_each_entry_rcu(pmu, &pmus, entry) {
cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
if (cpuctx->unique_pmu != pmu)
goto next;
perf_event_comm_ctx(&cpuctx->ctx, comm_event);

ctxn = pmu->task_ctx_nr;
if (ctxn < 0)
goto next;

ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
if (ctx)
perf_event_comm_ctx(ctx, comm_event);
next:
put_cpu_ptr(pmu->pmu_cpu_context);
}
rcu_read_unlock();
perf_event_aux(perf_event_comm_match,
perf_event_comm_output,
comm_event,
NULL);
}

void perf_event_comm(struct task_struct *task)
Expand Down Expand Up @@ -4708,8 +4682,9 @@ struct perf_mmap_event {
};

static void perf_event_mmap_output(struct perf_event *event,
struct perf_mmap_event *mmap_event)
void *data)
{
struct perf_mmap_event *mmap_event = data;
struct perf_output_handle handle;
struct perf_sample_data sample;
int size = mmap_event->event_id.header.size;
Expand All @@ -4736,46 +4711,24 @@ static void perf_event_mmap_output(struct perf_event *event,
}

static int perf_event_mmap_match(struct perf_event *event,
struct perf_mmap_event *mmap_event,
int executable)
void *data)
{
if (event->state < PERF_EVENT_STATE_INACTIVE)
return 0;

if (!event_filter_match(event))
return 0;

if ((!executable && event->attr.mmap_data) ||
(executable && event->attr.mmap))
return 1;

return 0;
}

static void perf_event_mmap_ctx(struct perf_event_context *ctx,
struct perf_mmap_event *mmap_event,
int executable)
{
struct perf_event *event;
struct perf_mmap_event *mmap_event = data;
struct vm_area_struct *vma = mmap_event->vma;
int executable = vma->vm_flags & VM_EXEC;

list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
if (perf_event_mmap_match(event, mmap_event, executable))
perf_event_mmap_output(event, mmap_event);
}
return (!executable && event->attr.mmap_data) ||
(executable && event->attr.mmap);
}

static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)
{
struct perf_cpu_context *cpuctx;
struct perf_event_context *ctx;
struct vm_area_struct *vma = mmap_event->vma;
struct file *file = vma->vm_file;
unsigned int size;
char tmp[16];
char *buf = NULL;
const char *name;
struct pmu *pmu;
int ctxn;

memset(tmp, 0, sizeof(tmp));

Expand Down Expand Up @@ -4831,27 +4784,10 @@ static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)

mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size;

rcu_read_lock();
list_for_each_entry_rcu(pmu, &pmus, entry) {
cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
if (cpuctx->unique_pmu != pmu)
goto next;
perf_event_mmap_ctx(&cpuctx->ctx, mmap_event,
vma->vm_flags & VM_EXEC);

ctxn = pmu->task_ctx_nr;
if (ctxn < 0)
goto next;

ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
if (ctx) {
perf_event_mmap_ctx(ctx, mmap_event,
vma->vm_flags & VM_EXEC);
}
next:
put_cpu_ptr(pmu->pmu_cpu_context);
}
rcu_read_unlock();
perf_event_aux(perf_event_mmap_match,
perf_event_mmap_output,
mmap_event,
NULL);

kfree(buf);
}
Expand Down

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