From d1eb650ff4130972fa21462fa49cd35a2865403b Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Tue, 24 Nov 2009 16:56:45 -0500 Subject: tracepoint: Move signal sending tracepoint to events/signal.h Move signal sending event to events/signal.h. This patch also renames sched_signal_send event to signal_generate. Changes in v4: - Fix a typo of task_struct pointer. Changes in v3: - Add docbook style comments Changes in v2: - Add siginfo argument - Add siginfo storing macro Signed-off-by: Masami Hiramatsu Reviewed-by: Jason Baron Acked-by: Roland McGrath Cc: systemtap Cc: DLE Cc: Oleg Nesterov LKML-Reference: <20091124215645.30449.60208.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar --- kernel/signal.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'kernel/signal.c') diff --git a/kernel/signal.c b/kernel/signal.c index 6705320784fd..a1e0cc6b32c3 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -27,7 +27,8 @@ #include #include #include -#include +#define CREATE_TRACE_POINTS +#include #include #include @@ -834,7 +835,7 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t, struct sigqueue *q; int override_rlimit; - trace_sched_signal_send(sig, t); + trace_signal_generate(sig, info, t); assert_spin_locked(&t->sighand->siglock); -- cgit v1.2.3-70-g09d2 From f9d4257e01d266e67420cc99d456b6d4c8464f54 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Tue, 24 Nov 2009 16:56:51 -0500 Subject: 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(+) (limited to 'kernel/signal.c') 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) { -- cgit v1.2.3-70-g09d2 From ba005e1f417295d28cd1563ab82bc33af07fb16a Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Tue, 24 Nov 2009 16:56:58 -0500 Subject: tracepoint: Add signal loss events Add signal_overflow_fail and signal_lose_info tracepoints for signal-lost events. Changes in v3: - Add docbook style comments Changes in v2: - Use siginfo string macro Suggested-by: Roland McGrath Reviewed-by: Jason Baron Signed-off-by: Masami Hiramatsu Acked-by: Roland McGrath Cc: systemtap Cc: DLE Cc: Oleg Nesterov LKML-Reference: <20091124215658.30449.9934.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar --- include/trace/events/signal.h | 68 +++++++++++++++++++++++++++++++++++++++++++ kernel/signal.c | 19 ++++++++---- 2 files changed, 82 insertions(+), 5 deletions(-) (limited to 'kernel/signal.c') diff --git a/include/trace/events/signal.h b/include/trace/events/signal.h index a6d71de0dc0d..a510b75ac304 100644 --- a/include/trace/events/signal.h +++ b/include/trace/events/signal.h @@ -99,6 +99,74 @@ TRACE_EVENT(signal_deliver, __entry->sig, __entry->errno, __entry->code, __entry->sa_handler, __entry->sa_flags) ); + +/** + * signal_overflow_fail - called when signal queue is overflow + * @sig: signal number + * @group: signal to process group or not (bool) + * @info: pointer to struct siginfo + * + * Kernel fails to generate 'sig' signal with 'info' siginfo, because + * siginfo queue is overflow, and the signal is dropped. + * 'group' is not 0 if the signal will be sent to a process group. + * 'sig' is always one of RT signals. + */ +TRACE_EVENT(signal_overflow_fail, + + TP_PROTO(int sig, int group, struct siginfo *info), + + TP_ARGS(sig, group, info), + + TP_STRUCT__entry( + __field( int, sig ) + __field( int, group ) + __field( int, errno ) + __field( int, code ) + ), + + TP_fast_assign( + __entry->sig = sig; + __entry->group = group; + TP_STORE_SIGINFO(__entry, info); + ), + + TP_printk("sig=%d group=%d errno=%d code=%d", + __entry->sig, __entry->group, __entry->errno, __entry->code) +); + +/** + * signal_lose_info - called when siginfo is lost + * @sig: signal number + * @group: signal to process group or not (bool) + * @info: pointer to struct siginfo + * + * Kernel generates 'sig' signal but loses 'info' siginfo, because siginfo + * queue is overflow. + * 'group' is not 0 if the signal will be sent to a process group. + * 'sig' is always one of non-RT signals. + */ +TRACE_EVENT(signal_lose_info, + + TP_PROTO(int sig, int group, struct siginfo *info), + + TP_ARGS(sig, group, info), + + TP_STRUCT__entry( + __field( int, sig ) + __field( int, group ) + __field( int, errno ) + __field( int, code ) + ), + + TP_fast_assign( + __entry->sig = sig; + __entry->group = group; + TP_STORE_SIGINFO(__entry, info); + ), + + TP_printk("sig=%d group=%d errno=%d code=%d", + __entry->sig, __entry->group, __entry->errno, __entry->code) +); #endif /* _TRACE_SIGNAL_H */ /* This part must be outside protection */ diff --git a/kernel/signal.c b/kernel/signal.c index 349d44937406..93e72e5feae6 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -897,12 +897,21 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t, break; } } else if (!is_si_special(info)) { - if (sig >= SIGRTMIN && info->si_code != SI_USER) - /* - * Queue overflow, abort. We may abort if the signal was rt - * and sent by user using something other than kill(). - */ + if (sig >= SIGRTMIN && info->si_code != SI_USER) { + /* + * Queue overflow, abort. We may abort if the + * signal was rt and sent by user using something + * other than kill(). + */ + trace_signal_overflow_fail(sig, group, info); return -EAGAIN; + } else { + /* + * This is a silent loss of information. We still + * send the signal, but the *info bits are lost. + */ + trace_signal_lose_info(sig, group, info); + } } out_set: -- cgit v1.2.3-70-g09d2