adulau/aha
1
0
Fork 0
mirror of https://github.com/adulau/aha.git synced 2024-12-28 03:36:19 +00:00
Code Issues Projects Releases Packages Wiki Activity

perf_counter: optionally provide the pid/tid of the sampled task

Browse source 
Allow cpu wide counters to profile userspace by providing what process
the sample belongs to.

This raises the first issue with the output type, lots of these
options: group, tid, callchain, etc.. are non-exclusive and could be
combined, suggesting a bitfield.

However, things like the mmap() data stream doesn't fit in that.

How to split the type field...

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Orig-LKML-Reference: <20090325113317.013775235@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Peter Zijlstra 2009-03-25 12:30:25 +01:00 committed by Ingo Molnar
parent 63e35b25d6
commit ea5d20cf99
2 changed files with 20 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

5
include/linux/perf_counter.h
View file

@ -127,8 +127,9 @@ struct perf_counter_hw_event {
exclude_kernel : 1, /* ditto kernel */
exclude_hv : 1, /* ditto hypervisor */
exclude_idle : 1, /* don't count when idle */
include_tid : 1, /* include the tid */
__reserved_1 : 55;
__reserved_1 : 54;
__u32 extra_config_len;
__u32 __reserved_4;
@ -164,6 +165,8 @@ struct perf_event_header {
enum perf_event_type {
PERF_EVENT_IP = 0,
PERF_EVENT_GROUP = 1,
__PERF_EVENT_TID = 0x100,
};
#ifdef __KERNEL__

18
kernel/perf_counter.c
View file

@ -1528,16 +1528,30 @@ out:
static void perf_output_simple(struct perf_counter *counter,
int nmi, struct pt_regs *regs)
{
unsigned int size;
struct {
struct perf_event_header header;
u64 ip;
u32 pid, tid;
} event;
event.header.type = PERF_EVENT_IP;
event.header.size = sizeof(event);
event.ip = instruction_pointer(regs);
perf_output_write(counter, nmi, &event, sizeof(event));
size = sizeof(event);
if (counter->hw_event.include_tid) {
/* namespace issues */
event.pid = current->group_leader->pid;
event.tid = current->pid;
event.header.type |= __PERF_EVENT_TID;
} else
size -= sizeof(u64);
event.header.size = size;
perf_output_write(counter, nmi, &event, size);
}
static void perf_output_group(struct perf_counter *counter, int nmi)