public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: "Wangnan (F)" <wangnan0@huawei.com>
To: <acme@kernel.org>, <masami.hiramatsu.pt@hitachi.com>,
	<rostedt@goodmis.org>
Cc: <mingo@redhat.com>, <namhyung@kernel.org>, <pi3orama@163.com>,
	<lizefan@huawei.com>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v3 2/6] perf probe: Fix list result when neither dwarf nor map can't find symbol
Date: Wed, 26 Aug 2015 19:03:03 +0800	[thread overview]
Message-ID: <55DD9CE7.1070806@huawei.com> (raw)
In-Reply-To: <1440586666-235233-3-git-send-email-wangnan0@huawei.com>

Please ignore this one, and use the identical one with shorter title.

Sorry for the noisy.

On 2015/8/26 18:57, Wang Nan wrote:
> 'perf probe -l' reports error if it is unable find symbol through
> address. Here is an example.
>
>   # echo 'p:probe_libc/abs_5 /lib64/libc.so.6:0x5' >
>            /sys/kernel/debug/tracing/uprobe_events
>   # cat /sys/kernel/debug/tracing/uprobe_events
>    p:probe_libc/abs_5 /lib64/libc.so.6:0x0000000000000005
>   # perf probe -l
>     Error: Failed to show event list
>
> Also, this situation triggers a logical inconsistency in
> convert_to_perf_probe_point() that, it returns ENOMEM but actually
> it never try strdup().
>
> This patch removes !tp->module && !is_kprobe condition, so it
> always uses address to build function name if symbol not found.
>
> Test result:
>
>   # perf probe -l
>     probe_libc:abs_5     (on 0x5 in /lib64/libc.so.6)
>
> Signed-off-by: Wang Nan <wangnan0@huawei.com>
> Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
> Cc: Namhyung Kim <namhyung@kernel.org>
> Cc: Steven Rostedt <rostedt@goodmis.org>
> ---
>   tools/perf/util/probe-event.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
> index 6c7e538..f7bacbb 100644
> --- a/tools/perf/util/probe-event.c
> +++ b/tools/perf/util/probe-event.c
> @@ -1866,7 +1866,7 @@ static int convert_to_perf_probe_point(struct probe_trace_point *tp,
>   	if (tp->symbol) {
>   		pp->function = strdup(tp->symbol);
>   		pp->offset = tp->offset;
> -	} else if (!tp->module && !is_kprobe) {
> +	} else {
>   		ret = e_snprintf(buf, 128, "0x%" PRIx64, (u64)tp->address);
>   		if (ret < 0)
>   			return ret;



  reply	other threads:[~2015-08-26 11:03 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-08-26 10:57 [PATCH v3 0/6] perf probe, tracing/uprobes: Support probing at absolute address Wang Nan
2015-08-26 10:57 ` [PATCH v3 1/6] perf probe: Prevent segfault when reading probe point with " Wang Nan
2015-08-26 10:57 ` [PATCH v3 2/6] perf probe: Fix list result when neither dwarf nor map can't find symbol Wang Nan
2015-08-26 11:03   ` Wangnan (F) [this message]
2015-08-26 10:57 ` [PATCH v3 2/6] perf probe: Fix list result when symbol can't be found Wang Nan
2015-08-26 12:27   ` 平松雅巳 / HIRAMATU,MASAMI
2015-08-28  6:41   ` [tip:perf/core] perf probe: Fix list result when symbol can' t " tip-bot for Wang Nan
2015-08-26 10:57 ` [PATCH v3 3/6] perf probe: Fix list result when address is zero Wang Nan
2015-08-26 12:14   ` 平松雅巳 / HIRAMATU,MASAMI
2015-08-28  6:42   ` [tip:perf/core] " tip-bot for Wang Nan
2015-08-26 10:57 ` [PATCH v3 4/6] perf probe: Fix error reported when offset without function Wang Nan
2015-08-26 12:21   ` 平松雅巳 / HIRAMATU,MASAMI
2015-08-28  6:42   ` [tip:perf/core] " tip-bot for Wang Nan
2015-08-26 10:57 ` [PATCH v3 5/6] perf probe: Support probing at absolute address Wang Nan
2015-08-26 12:16   ` 平松雅巳 / HIRAMATU,MASAMI
2015-08-28  6:42   ` [tip:perf/core] " tip-bot for Wang Nan
2015-08-26 10:57 ` [PATCH v3 6/6] tracing/uprobes: Do not print '0x (null)' when offset is 0 Wang Nan
2015-08-28  6:43   ` [tip:perf/core] " tip-bot for Wang Nan

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=55DD9CE7.1070806@huawei.com \
    --to=wangnan0@huawei.com \
    --cc=acme@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=lizefan@huawei.com \
    --cc=masami.hiramatsu.pt@hitachi.com \
    --cc=mingo@redhat.com \
    --cc=namhyung@kernel.org \
    --cc=pi3orama@163.com \
    --cc=rostedt@goodmis.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox