Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760277AbZKZK1e (ORCPT ); Thu, 26 Nov 2009 05:27:34 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759679AbZKZK1c (ORCPT ); Thu, 26 Nov 2009 05:27:32 -0500 Received: from hera.kernel.org ([140.211.167.34]:48415 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760263AbZKZK13 (ORCPT ); Thu, 26 Nov 2009 05:27:29 -0500 Date: Thu, 26 Nov 2009 10:25:07 GMT From: tip-bot for Masami Hiramatsu Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, roland@redhat.com, dle-develop@lists.sourceforge.net, oleg@redhat.com, tglx@linutronix.de, jbaron@redhat.com, mhiramat@redhat.com, mingo@elte.hu, systemtap@sources.redhat.com Reply-To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, roland@redhat.com, dle-develop@lists.sourceforge.net, oleg@redhat.com, tglx@linutronix.de, jbaron@redhat.com, mhiramat@redhat.com, systemtap@sources.redhat.com, mingo@elte.hu In-Reply-To: <20091124215658.30449.9934.stgit@dhcp-100-2-132.bos.redhat.com> References: <20091124215658.30449.9934.stgit@dhcp-100-2-132.bos.redhat.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] tracepoint: Add signal loss events Message-ID: Git-Commit-ID: ba005e1f417295d28cd1563ab82bc33af07fb16a X-Mailer: tip-git-log-daemon MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4491 Lines: 147 Commit-ID: ba005e1f417295d28cd1563ab82bc33af07fb16a Gitweb: http://git.kernel.org/tip/ba005e1f417295d28cd1563ab82bc33af07fb16a Author: Masami Hiramatsu AuthorDate: Tue, 24 Nov 2009 16:56:58 -0500 Committer: Ingo Molnar CommitDate: Thu, 26 Nov 2009 10:55:38 +0100 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(-) diff --git a/include/trace/events/signal.h b/include/trace/events/signal.h index a6d71de..a510b75 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 349d449..93e72e5 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: -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/