Re: [PATCH] show message when exceeded rlimit of pending signals

[Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>]

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 <nooiwa@miraclelinux.com>
> Acked-by: Ingo Molnar <mingo@elte.hu>
> ---
>  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: <bool>  (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