From: "Christophe Bédard via lttng-dev" <lttng-dev@lists.lttng.org> To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: lttng-dev <lttng-dev@lists.lttng.org> Subject: Re: Correctly using callstack-user context Date: Wed, 13 May 2020 09:42:42 -0400 [thread overview] Message-ID: <CAAS9dobxi52FyWn=9zVDkMMpmZztc1Q1msdiErMKhkDEYCtqCA@mail.gmail.com> (raw) In-Reply-To: <1486835767.11198.1589286441675.JavaMail.zimbra@efficios.com> [-- Attachment #1.1: Type: text/plain, Size: 838 bytes --] On Tue, 12 May 2020 at 08:27, Mathieu Desnoyers < mathieu.desnoyers@efficios.com> wrote: > How does your test program issue the system call ? Is it directly with > syscall() (see syscall(2) man page), or > does it call into libc ? Is your entire libc compiled with > -fno-omit-frame-pointer ? > Indirectly, through libc/libstdc++. We use the default system libs (which I assume use -O, which in turn implies -fomit-frame-pointer). > As soon as one library in the chain to the system call is compiled without > frame pointers, this is where the > stack walk stops. This is usually libc. > I see. Thanks for the information. Not sure we want to ship a custom libc unfortunately. Related question: how feasible would adding the callstack-user context to userspace events be? If it is feasible, is such a feature planned? Christophe [-- Attachment #1.2: Type: text/html, Size: 1677 bytes --] [-- Attachment #2: Type: text/plain, Size: 156 bytes --] _______________________________________________ lttng-dev mailing list lttng-dev@lists.lttng.org https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
WARNING: multiple messages have this Message-ID (diff)
From: "Christophe Bédard via lttng-dev" <lttng-dev@lists.lttng.org> To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: lttng-dev <lttng-dev@lists.lttng.org> Subject: Re: [lttng-dev] Correctly using callstack-user context Date: Wed, 13 May 2020 09:42:42 -0400 [thread overview] Message-ID: <CAAS9dobxi52FyWn=9zVDkMMpmZztc1Q1msdiErMKhkDEYCtqCA@mail.gmail.com> (raw) Message-ID: <20200513134242.B8ftyiYEWF_mIXu9zk6HIUpz_e3Kwsy7zEtnX3GdY_g@z> (raw) In-Reply-To: <1486835767.11198.1589286441675.JavaMail.zimbra@efficios.com> [-- Attachment #1.1: Type: text/plain, Size: 838 bytes --] On Tue, 12 May 2020 at 08:27, Mathieu Desnoyers < mathieu.desnoyers@efficios.com> wrote: > How does your test program issue the system call ? Is it directly with > syscall() (see syscall(2) man page), or > does it call into libc ? Is your entire libc compiled with > -fno-omit-frame-pointer ? > Indirectly, through libc/libstdc++. We use the default system libs (which I assume use -O, which in turn implies -fomit-frame-pointer). > As soon as one library in the chain to the system call is compiled without > frame pointers, this is where the > stack walk stops. This is usually libc. > I see. Thanks for the information. Not sure we want to ship a custom libc unfortunately. Related question: how feasible would adding the callstack-user context to userspace events be? If it is feasible, is such a feature planned? Christophe [-- Attachment #1.2: Type: text/html, Size: 1677 bytes --] [-- Attachment #2: Type: text/plain, Size: 156 bytes --] _______________________________________________ lttng-dev mailing list lttng-dev@lists.lttng.org https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
next prev parent reply other threads:[~2020-05-13 13:43 UTC|newest] Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-05-11 21:09 Correctly using callstack-user context Christophe Bédard via lttng-dev 2020-05-11 21:09 ` [lttng-dev] " Christophe Bédard via lttng-dev 2020-05-12 12:27 ` Mathieu Desnoyers via lttng-dev 2020-05-12 12:27 ` [lttng-dev] " Mathieu Desnoyers via lttng-dev 2020-05-13 13:42 ` Christophe Bédard via lttng-dev [this message] 2020-05-13 13:42 ` Christophe Bédard via lttng-dev 2020-05-13 14:02 ` Genevieve Bastien via lttng-dev 2020-05-13 14:02 ` [lttng-dev] " Genevieve Bastien via lttng-dev 2020-05-13 15:34 ` Christophe Bédard via lttng-dev 2020-05-13 15:34 ` [lttng-dev] " Christophe Bédard via lttng-dev
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='CAAS9dobxi52FyWn=9zVDkMMpmZztc1Q1msdiErMKhkDEYCtqCA@mail.gmail.com' \ --to=lttng-dev@lists.lttng.org \ --cc=bedard.christophe@gmail.com \ --cc=mathieu.desnoyers@efficios.com \ /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: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.