perf probe: Seaching the cache automatically

perf probe: Seaching the cache automatically

[Arnaldo Carvalho de Melo]

Hi Masami,

	While reviewing your latest patchkit I figured out I left some
sdt entries in my cache, cool! Tried to use but:

[root@jouet 22]# perf probe --cache --list
/usr/lib64/libc-2.23.so (88686319c72f1a9d9cd514af519aa5602880bab2):
sdt_libc:setjmp=setjmp
sdt_libc:longjmp=longjmp
sdt_libc:longjmp_target=longjmp_target
sdt_libc:memory_arena_reuse_free_list=memory_arena_reuse_free_list
sdt_libc:memory_heap_new=memory_heap_new
sdt_libc:memory_sbrk_less=memory_sbrk_less
sdt_libc:memory_arena_reuse_wait=memory_arena_reuse_wait
sdt_libc:memory_arena_reuse=memory_arena_reuse
sdt_libc:memory_arena_new=memory_arena_new
sdt_libc:memory_arena_retry=memory_arena_retry
sdt_libc:memory_heap_free=memory_heap_free
sdt_libc:memory_heap_less=memory_heap_less
sdt_libc:memory_heap_more=memory_heap_more
sdt_libc:memory_sbrk_more=memory_sbrk_more
sdt_libc:memory_malloc_retry=memory_malloc_retry
sdt_libc:memory_mallopt_free_dyn_thresholds=memory_mallopt_free_dyn_thresholds
sdt_libc:memory_realloc_retry=memory_realloc_retry
sdt_libc:memory_memalign_retry=memory_memalign_retry
sdt_libc:memory_calloc_retry=memory_calloc_retry
sdt_libc:memory_mallopt=memory_mallopt
sdt_libc:memory_mallopt_mxfast=memory_mallopt_mxfast
sdt_libc:memory_mallopt_arena_max=memory_mallopt_arena_max
sdt_libc:memory_mallopt_arena_test=memory_mallopt_arena_test
sdt_libc:memory_mallopt_mmap_max=memory_mallopt_mmap_max
sdt_libc:memory_mallopt_mmap_threshold=memory_mallopt_mmap_threshold
sdt_libc:memory_mallopt_top_pad=memory_mallopt_top_pad
sdt_libc:memory_mallopt_trim_threshold=memory_mallopt_trim_threshold
sdt_libc:memory_mallopt_perturb=memory_mallopt_perturb
sdt_libc:memory_mallopt_check_action=memory_mallopt_check_action
sdt_libc:lll_lock_wait_private=lll_lock_wait_private
[root@jouet 22]# 

[root@jouet 22]# perf record --event sdt_libc:memory_heap_new -a
event syntax error: 'sdt_libc:memory_heap_new'
                     \___ unknown tracepoint

Error:	File /sys/kernel/debug/tracing/events/sdt_libc/memory_heap_new not found.
Hint:	Perhaps this kernel misses some CONFIG_ setting to enable this feature?.

Run 'perf list' for a list of valid events

 Usage: perf record [<options>] [<command>]
    or: perf record [<options>] -- <command> [<options>]

    -e, --event <event>   event selector. use 'perf list' to list available events
[root@jouet 22]#

So probably I need to do something else, will dig that, scratching my head, as
my expectation was that it would look at that cache and pick things from there,
etc. Perhaps this is in a patch in this series, will check...

- Arnaldo

Re: perf probe: Seaching the cache automatically

[Masami Hiramatsu]

On Wed, 13 Jul 2016 16:11:37 -0300
Arnaldo Carvalho de Melo <acme@kernel.org> wrote:

> Hi Masami,
> 
> 	While reviewing your latest patchkit I figured out I left some
> sdt entries in my cache, cool! Tried to use but:
> 
> [root@jouet 22]# perf probe --cache --list
> /usr/lib64/libc-2.23.so (88686319c72f1a9d9cd514af519aa5602880bab2):
> sdt_libc:setjmp=setjmp
> sdt_libc:longjmp=longjmp
> sdt_libc:longjmp_target=longjmp_target
> sdt_libc:memory_arena_reuse_free_list=memory_arena_reuse_free_list
> sdt_libc:memory_heap_new=memory_heap_new
> sdt_libc:memory_sbrk_less=memory_sbrk_less
> sdt_libc:memory_arena_reuse_wait=memory_arena_reuse_wait
> sdt_libc:memory_arena_reuse=memory_arena_reuse
> sdt_libc:memory_arena_new=memory_arena_new
> sdt_libc:memory_arena_retry=memory_arena_retry
> sdt_libc:memory_heap_free=memory_heap_free
> sdt_libc:memory_heap_less=memory_heap_less
> sdt_libc:memory_heap_more=memory_heap_more
> sdt_libc:memory_sbrk_more=memory_sbrk_more
> sdt_libc:memory_malloc_retry=memory_malloc_retry
> sdt_libc:memory_mallopt_free_dyn_thresholds=memory_mallopt_free_dyn_thresholds
> sdt_libc:memory_realloc_retry=memory_realloc_retry
> sdt_libc:memory_memalign_retry=memory_memalign_retry
> sdt_libc:memory_calloc_retry=memory_calloc_retry
> sdt_libc:memory_mallopt=memory_mallopt
> sdt_libc:memory_mallopt_mxfast=memory_mallopt_mxfast
> sdt_libc:memory_mallopt_arena_max=memory_mallopt_arena_max
> sdt_libc:memory_mallopt_arena_test=memory_mallopt_arena_test
> sdt_libc:memory_mallopt_mmap_max=memory_mallopt_mmap_max
> sdt_libc:memory_mallopt_mmap_threshold=memory_mallopt_mmap_threshold
> sdt_libc:memory_mallopt_top_pad=memory_mallopt_top_pad
> sdt_libc:memory_mallopt_trim_threshold=memory_mallopt_trim_threshold
> sdt_libc:memory_mallopt_perturb=memory_mallopt_perturb
> sdt_libc:memory_mallopt_check_action=memory_mallopt_check_action
> sdt_libc:lll_lock_wait_private=lll_lock_wait_private
> [root@jouet 22]# 
> 
> [root@jouet 22]# perf record --event sdt_libc:memory_heap_new -a
> event syntax error: 'sdt_libc:memory_heap_new'
>                      \___ unknown tracepoint
> 
> Error:	File /sys/kernel/debug/tracing/events/sdt_libc/memory_heap_new not found.
> Hint:	Perhaps this kernel misses some CONFIG_ setting to enable this feature?.
> 
> Run 'perf list' for a list of valid events
> 
>  Usage: perf record [<options>] [<command>]
>     or: perf record [<options>] -- <command> [<options>]
> 
>     -e, --event <event>   event selector. use 'perf list' to list available events
> [root@jouet 22]#
> 
> So probably I need to do something else, will dig that, scratching my head, as
> my expectation was that it would look at that cache and pick things from there,
> etc. Perhaps this is in a patch in this series, will check...

Ah, yes, that is currently under development. What happened in the series is I dropped
direct SDT record, because I felt it was not prepared to be merged. This is why
perf list still doesn't show the SDT events. (only perf-probe shows it)

So, currently, you have to use perf-probe to set up SDT events as same as
other dynamic events. So, before run the perf record, please run below command.

# perf probe sdt_libc:memory_heap_new

Then you can record the event.

Thanks,

-- 
Masami Hiramatsu <mhiramat@kernel.org>