Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932196AbZJ0I1f (ORCPT ); Tue, 27 Oct 2009 04:27:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932140AbZJ0I1d (ORCPT ); Tue, 27 Oct 2009 04:27:33 -0400 Received: from mailgw.miraclelinux.com ([122.216.84.157]:61918 "EHLO mailgw.miraclelinux.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932184AbZJ0I1a (ORCPT ); Tue, 27 Oct 2009 04:27:30 -0400 Message-ID: <4AE6AEEB.3020109@miraclelinux.com> Date: Tue, 27 Oct 2009 17:27:23 +0900 From: nooiwa User-Agent: Thunderbird 2.0.0.23 (Windows/20090812) MIME-Version: 1.0 To: Hiroshi Shimamoto CC: Ingo Molnar , roland@redhat.com, akpm@linux-foundation.org, oleg@redhat.com, LKML , Thomas Gleixner , Peter Zijlstra Subject: Re: [PATCH] show message when exceeded rlimit of pending signals References: <4AE1804A.2050404@miraclelinux.com> <20091023114600.GG5886@elte.hu> <4AE2A6A1.1070904@miraclelinux.com> <4AE2C151.8070006@miraclelinux.com> <20091024085848.GA23215@elte.hu> <4AE57745.8080701@miraclelinux.com> <20091026113800.GA9503@elte.hu> <4AE5D0B2.2050706@miraclelinux.com> <20091026202808.GA7107@elte.hu> <4AE661D4.5090306@miraclelinux.com> <4AE678C6.2090007@ct.jp.nec.com> In-Reply-To: <4AE678C6.2090007@ct.jp.nec.com> Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5942 Lines: 198 Hi Hiroshi > And nitpicks below. Thank you so much. Sorry, I will run scripts/checkpatch.pl in the next time. > there are white spaces before tabs. oops... >> + printk(KERN_WARNING "%s/%d: reached the limit of pending signals.\n", current->comm, current->pid); > > this line over 80 characters. I deleted "KERN_WARNING", because there is not it in print_faital_signal(). Thanks you. Naohiro Ooiwa Signed-off-by: Naohiro Ooiwa Acked-by: Ingo Molnar --- Documentation/kernel-parameters.txt | 11 +++++++++-- kernel/signal.c | 17 ++++++++++++++--- 2 files changed, 23 insertions(+), 5 deletions(-) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 9107b38..6b74dd4 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2032,8 +2032,15 @@ and is between 256 and 4096 characters. It is defined in the file print-fatal-signals= [KNL] debug: print fatal signals - print-fatal-signals=1: print segfault info to - the kernel console. + + If enabled, warn about various signal handling + related application anomalies: too many signals, + too many POSIX.1 timers, fatal signals causing a + coredump - etc. + + If you hit the warning due to signal overflow, + you might want to try "ulimit -i unlimited". + default: off. printk.time= Show timing data prefixed to each printk message line diff --git a/kernel/signal.c b/kernel/signal.c index 6705320..8588833 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -41,6 +41,8 @@ static struct kmem_cache *sigqueue_cachep; +int print_fatal_signals __read_mostly; + static void __user *sig_handler(struct task_struct *t, int sig) { return t->sighand->action[sig - 1].sa.sa_handler; @@ -188,6 +190,13 @@ int next_signal(struct sigpending *pending, sigset_t *mask) return sig; } +static void show_reach_rlimit_sigpending(void) +{ + if (printk_ratelimit()) + printk("%s/%d: reached the limit of pending signals.\n", + current->comm, current->pid); +} + /* * allocate a new signal queue record * - this may be called without locks if and only if t == current, otherwise an @@ -209,8 +218,12 @@ static struct sigqueue *__sigqueue_alloc(struct task_struct *t, gfp_t flags, atomic_inc(&user->sigpending); if (override_rlimit || atomic_read(&user->sigpending) <= - t->signal->rlim[RLIMIT_SIGPENDING].rlim_cur) + t->signal->rlim[RLIMIT_SIGPENDING].rlim_cur) { q = kmem_cache_alloc(sigqueue_cachep, flags); + } else { + if (print_fatal_signals) + show_reach_rlimit_sigpending(); + } if (unlikely(q == NULL)) { atomic_dec(&user->sigpending); free_uid(user); @@ -925,8 +938,6 @@ static int send_signal(int sig, struct siginfo *info, struct task_struct *t, return __send_signal(sig, info, t, group, from_ancestor_ns); } -int print_fatal_signals; - static void print_fatal_signal(struct pt_regs *regs, int signr) { printk("%s/%d: potentially unexpected fatal signal %d.\n", -- 1.5.4.1 Hiroshi Shimamoto wrote: > Naohiro Ooiwa wrote: >> Hi Ingo, >> >>> Here's a slightly improved version of the text: >> Thank you for your review and collect my English. >> >>>> +int print_fatal_signals; >>> i'd suggest __read_mostly. >>> Plus please move variables to the top of the file. (i know this comes >>> from the previous code but we can improve it while we are touching it) >> Of course. You're right, if we found one like it, >> I want to improve the code little by little too. >> >> How is the following patch. > > If you can provide a test case, it's helpful to confirm this improve. > And nitpicks below. > >> Signed-off-by: Naohiro Ooiwa >> Acked-by: Ingo Molnar >> --- >> Documentation/kernel-parameters.txt | 13 ++++++++++--- >> kernel/signal.c | 16 +++++++++++++--- >> 2 files changed, 23 insertions(+), 6 deletions(-) >> >> diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt >> index 9107b38..8492ad3 100644 >> --- a/Documentation/kernel-parameters.txt >> +++ b/Documentation/kernel-parameters.txt >> @@ -2032,9 +2032,16 @@ and is between 256 and 4096 characters. It is defined in the file >> >> print-fatal-signals= >> [KNL] debug: print fatal signals >> - print-fatal-signals=1: print segfault info to >> - the kernel console. >> - default: off. >> + >> + If enabled, warn about various signal handling >> + related application anomalies: too many signals, >> + too many POSIX.1 timers, fatal signals causing a >> + coredump - etc. >> + >> + If you hit the warning due to signal overflow, >> + you might want to try "ulimit -i unlimited". >> + >> + default: off. > > there are white spaces before tabs. > >> printk.time= Show timing data prefixed to each printk message line >> Format: (1/Y/y=enable, 0/N/n=disable) >> diff --git a/kernel/signal.c b/kernel/signal.c >> index 6705320..c913eb7 100644 >> --- a/kernel/signal.c >> +++ b/kernel/signal.c >> @@ -41,6 +41,8 @@ >> >> static struct kmem_cache *sigqueue_cachep; >> >> +int print_fatal_signals __read_mostly; >> + >> static void __user *sig_handler(struct task_struct *t, int sig) >> { >> return t->sighand->action[sig - 1].sa.sa_handler; >> @@ -188,6 +190,12 @@ int next_signal(struct sigpending *pending, sigset_t *mask) >> return sig; >> } >> >> +static void show_reach_rlimit_sigpending(void) >> +{ >> + if (printk_ratelimit()) >> + printk(KERN_WARNING "%s/%d: reached the limit of pending signals.\n", current->comm, current->pid); > > this line over 80 characters. > > thanks, > Hiroshi -- 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/