tracepoint: Add signal deliver event

Add a tracepoint where a process gets a signal. This tracepoint
shows signal-number, sa-handler and sa-flag.

Changes in v3:
 - Add docbook style comments

Changes in v2:
 - Add siginfo argument
 - Fix comment

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Reviewed-by: Jason Baron <jbaron@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Oleg Nesterov <oleg@redhat.com>
LKML-Reference: <20091124215651.30449.20926.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Masami Hiramatsu 2009-11-24 16:56:51 -05:00 committed by Ingo Molnar
parent d1eb650ff4
commit f9d4257e01
2 changed files with 42 additions and 0 deletions

View File

@ -60,6 +60,45 @@ TRACE_EVENT(signal_generate,
__entry->comm, __entry->pid)
);
/**
* signal_deliver - called when a signal is delivered
* @sig: signal number
* @info: pointer to struct siginfo
* @ka: pointer to struct k_sigaction
*
* A 'sig' signal is delivered to current process with 'info' siginfo,
* and it will be handled by 'ka'. ka->sa.sa_handler can be SIG_IGN or
* SIG_DFL.
* Note that some signals reported by signal_generate tracepoint can be
* lost, ignored or modified (by debugger) before hitting this tracepoint.
* This means, this can show which signals are actually delivered, but
* matching generated signals and delivered signals may not be correct.
*/
TRACE_EVENT(signal_deliver,
TP_PROTO(int sig, struct siginfo *info, struct k_sigaction *ka),
TP_ARGS(sig, info, ka),
TP_STRUCT__entry(
__field( int, sig )
__field( int, errno )
__field( int, code )
__field( unsigned long, sa_handler )
__field( unsigned long, sa_flags )
),
TP_fast_assign(
__entry->sig = sig;
TP_STORE_SIGINFO(__entry, info);
__entry->sa_handler = (unsigned long)ka->sa.sa_handler;
__entry->sa_flags = ka->sa.sa_flags;
),
TP_printk("sig=%d errno=%d code=%d sa_handler=%lx sa_flags=%lx",
__entry->sig, __entry->errno, __entry->code,
__entry->sa_handler, __entry->sa_flags)
);
#endif /* _TRACE_SIGNAL_H */
/* This part must be outside protection */

View File

@ -1840,6 +1840,9 @@ relock:
ka = &sighand->action[signr-1];
}
/* Trace actually delivered signals. */
trace_signal_deliver(signr, info, ka);
if (ka->sa.sa_handler == SIG_IGN) /* Do nothing. */
continue;
if (ka->sa.sa_handler != SIG_DFL) {