From f9d4257e01d266e67420cc99d456b6d4c8464f54 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Tue, 24 Nov 2009 16:56:51 -0500 Subject: [PATCH] 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 Reviewed-by: Jason Baron Acked-by: Roland McGrath Cc: systemtap Cc: DLE Cc: Oleg Nesterov LKML-Reference: <20091124215651.30449.20926.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar --- include/trace/events/signal.h | 39 +++++++++++++++++++++++++++++++++++ kernel/signal.c | 3 +++ 2 files changed, 42 insertions(+) diff --git a/include/trace/events/signal.h b/include/trace/events/signal.h index ef51756a801d..a6d71de0dc0d 100644 --- a/include/trace/events/signal.h +++ b/include/trace/events/signal.h @@ -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 */ diff --git a/kernel/signal.c b/kernel/signal.c index a1e0cc6b32c3..349d44937406 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -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) { -- 2.20.1