Re: [BUGFIX PATCH perf/core ] perf-probe: Fix to add missed brace around if block

From: Arnaldo Carvalho de Melo
Date: Thu Aug 13 2015 - 14:09:53 EST


Em Thu, Aug 13, 2015 at 06:55:41AM +0900, Masami Hiramatsu escreveu:
> The commit 75186a9b09e4 (perf probe: Fix to show lines of
> sys_ functions correctly) introduced a bug by a missed brace
> around if block. This fixes to add it.
>
> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>

Thanks! now it works:

[root@zoo ~]# perf probe 'get_timeval=sys_select:11 tv_sec=tv.tv_sec tv_usec=tv.tv_usec'
Added new event:
probe:get_timeval (on sys_select:11 with tv_sec=tv.tv_sec tv_usec=tv.tv_usec)

You can now use it in all perf tools, such as:

perf record -e probe:get_timeval -aR sleep 1

[root@zoo ~]# perf probe -l
probe:get_timeval (on SYSC_select:11@/home/git/linux/fs/select.c with tv_sec tv_usec)
probe:vfs_getname (on getname_flags:72@/home/git/linux/fs/namei.c with pathname)
[root@zoo ~]#

Now we have:

# strace -e select -p 960
Process 960 attached
select(13, [4 5 7 9 10 11 12], [], [5], {10, 0}) = 0 (Timeout)
select(13, [4 5 7 9 10 11 12], [], [5], {9, 999999}) = 0 (Timeout)
select(13, [4 5 7 9 10 11 12], [], [5], {10, 0}) = 0 (Timeout)
select(13, [4 5 7 9 10 11 12], [], [5], {10, 0}) = 0 (Timeout)
select(13, [4 5 7 9 10 11 12], [], [5], {0, 3072}) = 0 (Timeout)

At the same time as:

# trace --ev probe:get_timeval -e select -p 960
0.322 ( 0.013 ms): select(n: 13, inp: 0x55ac425996c0, outp: 0x55ac42599750, exp: 0x55ac425997e0, tvp: 0x7ffd3371fa30) ...
0.322 ( ): probe:get_timeval:(ffffffff81228f15) tv_sec=10 tv_usec=0)
10022.189 (10021.880 ms): ... [continued]: select()) = 0 Timeout
10022.681 ( 0.043 ms): select(n: 13, inp: 0x55ac425996c0, outp: 0x55ac42599750, exp: 0x55ac425997e0, tvp: 0x7ffd3371fa30) ...
10022.681 ( ): probe:get_timeval:(ffffffff81228f15) tv_sec=9 tv_usec=999999)
20040.673 (10018.035 ms): ... [continued]: select()) = 0 Timeout
20041.174 ( 0.046 ms): select(n: 13, inp: 0x55ac425996c0, outp: 0x55ac42599750, exp: 0x55ac425997e0, tvp: 0x7ffd3371fa30) ...
20041.174 ( ): probe:get_timeval:(ffffffff81228f15) tv_sec=10 tv_usec=0)
30063.041 (10021.912 ms): ... [continued]: select()) = 0 Timeout
30063.581 ( 0.042 ms): select(n: 13, inp: 0x55ac425996c0, outp: 0x55ac42599750, exp: 0x55ac425997e0, tvp: 0x7ffd3371fa30) ...
30063.581 ( ): probe:get_timeval:(ffffffff81228f15) tv_sec=10 tv_usec=0)
40085.448 (10021.909 ms): ... [continued]: select()) = 0 Timeout
40087.983 ( 0.033 ms): select(n: 13, inp: 0x55ac425996c0, outp: 0x55ac42599750, exp: 0x55ac425997e0, tvp: 0x7ffd3371fa30) ...
40087.983 ( ): probe:get_timeval:(ffffffff81228f15) tv_sec=0 tv_usec=3072)
40091.202 ( 3.252 ms): ... [continued]: select()) = 0 Timeout

Seems to be working, now its just to add support in 'perf trace' for a
"get_timeval" wannabe tracepoint in the same fashion as there is support for
another wannabe tracepoint: "vfs_getname", add more of these where timevals are
copied from the kernel, etc.

Anyway, now 'perf probe' suits my needs with syscalls, applied!

Thanks,

- Arnaldo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/