Re: [PATCH 3/3] perf events: Change perf parameter --pid to process-wide collection instead of thread-wide

[Li Zefan <lizf@cn.fujitsu.com>]

Zhang, Yanmin wrote:
> From: Zhang, Yanmin <yanmin_zhang@linux.intel.com>
> 
> Parameter --pid (or -p) of perf currently means a thread-wide collection.
> For exmaple, if a process whose id is 8888 has 10 threads, 'perf top -p 8888'
> just collects the main thread statistics. That's misleading. Users are
> used to attach a whole process when debugging a process by gdb. To follow
> normal usage style, the patch change --pid to process-wide collection and
> add --tid (-t) to mean a thread-wide collection.
> 
> Usage example is:
> #perf top -p 8888
> #perf record -p 8888 -f sleep 10
> #perf stat -p 8888 -f sleep 10
> Above commands collect the statistics of all threads of process 8888.
> 
> Signed-off-by: Zhang Yanmin <yanmin_zhang@linux.intel.com>
> 

Seems this patch causes seg faults:

# ./perf sched record
Segmentation fault
# ./perf kmem record
Segmentation fault
# ./perf timechart record
Segmentation fault