Re: [PATCH 24/41] perf tools: Add cpu to struct thread

From: Adrian Hunter
Date: Tue Jul 15 2014 - 13:58:24 EST

On 15/07/2014 5:24 p.m., Arnaldo Carvalho de Melo wrote:
Em Mon, Jul 14, 2014 at 01:02:48PM +0300, Adrian Hunter escreveu:
Tools may wish to track on which cpu a thread
is running. Add 'cpu' to struct thread for
that purpose.

This will be used to determine the cpu when
decoding a per-thread Instruction Trace.

Humm, is this the last cpu we got some event telling the cpu was running
on? Continuing looking at the patches...

Yes. Intel PT decoding uses sched_switch events to determine which
task is running on which cpu. The Intel PT data comes straight
from the hardware which doesn't know about linux threads.

- Arnaldo

Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
tools/perf/util/thread.c | 1 +
tools/perf/util/thread.h | 1 +
2 files changed, 2 insertions(+)

diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
index b9a3ee4..2f8c0c1 100644
--- a/tools/perf/util/thread.c
+++ b/tools/perf/util/thread.c
@@ -69,6 +69,7 @@ struct thread *thread__new(pid_t pid, pid_t tid)
thread->pid_ = pid;
thread->tid = tid;
thread->ppid = -1;
+ thread->cpu = -1;

comm_str = malloc(32);
diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h
index b4269af..e4920ff 100644
--- a/tools/perf/util/thread.h
+++ b/tools/perf/util/thread.h
@@ -17,6 +17,7 @@ struct thread {
pid_t pid_; /* Not all tools update this */
pid_t tid;
pid_t ppid;
+ int cpu;
char shortname[3];
bool comm_set;
bool dead; /* if set thread has exited */
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