Re: [PATCH] kernel.h: Add printk_ratelimited and pr_<level>_rl

From: Naohiro Ooiwa
Date: Thu Nov 05 2009 - 09:44:09 EST


Naohiro Ooiwa wrote:
> Ingo Molnar wrote:
>> * Joe Perches <joe@xxxxxxxxxxx> wrote:
>>
>>> Add a printk_ratelimited statement expression macro that uses a
>>> per-call ratelimit_state so that multiple subsystems output messages
>>> are not suppressed by a global __ratelimit state.
>>>
>>> Signed-off-by: Joe Perches <joe@xxxxxxxxxxx>
>>>
>>> diff --git a/include/linux/kernel.h b/include/linux/kernel.h
>>> index f4e3184..555560c 100644
>>> --- a/include/linux/kernel.h
>>> +++ b/include/linux/kernel.h
>>> @@ -407,6 +407,50 @@ static inline char *pack_hex_byte(char *buf, u8 byte)
>>> #endif
>>>
>>> /*
>>> + * ratelimited messages with local ratelimit_state,
>>> + * no local ratelimit_state used in the !PRINTK case
>>> + */
>>> +#ifdef CONFIG_PRINTK
>>> +#define printk_ratelimited(fmt, ...) ({ \
>>> + static struct ratelimit_state _rs = { \
>>> + .interval = DEFAULT_RATELIMIT_INTERVAL, \
>>> + .burst = DEFAULT_RATELIMIT_BURST, \
>>> + }; \
>>> + \
>>> + if (!__ratelimit(&_rs)) \
>>> + printk(fmt, ##__VA_ARGS__); \
>>> +})
>>> +#else
>>> +/* No effect, but we still get type checking even in the !PRINTK case: */
>>> +#define printk_ratelimited printk
>>> +#endif
>>> +
>>> +#define pr_emerg_rl(fmt, ...) \
>>> + printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
>>> +#define pr_alert_rl(fmt, ...) \
>>> + printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
>>> +#define pr_crit_rl(fmt, ...) \
>>> + printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
>>> +#define pr_err_rl(fmt, ...) \
>>> + printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
>>> +#define pr_warning_rl(fmt, ...) \
>>> + printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
>>> +#define pr_notice_rl(fmt, ...) \
>>> + printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
>>> +#define pr_info_rl(fmt, ...) \
>>> + printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
>>> +/* no pr_cont_rl, don't do that... */
>>> +/* If you are writing a driver, please use dev_dbg instead */
>>> +#if defined(DEBUG)
>>> +#define pr_debug_rl(fmt, ...) \
>>> + printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
>>> +#else
>>> +#define pr_debug_rl(fmt, ...) \
>>> + ({ if (0) printk_ratelimited(KERN_DEBUG pr_fmt(fmt), \
>>> + ##__VA_ARGS__); 0; })
>>> +#endif
>>> +
>> Looks like a useful addition. Somewhat bloatier, but then again, more
>> correct and the bloat problem can be solved by explicit state
>> definitions.
>>
>> Ingo
>
> I waiting for this patch to merge.
> And then, I think I will remake my patch.
>
> How do you delete printk_ratelimit() in this patch at a same time ?
>
> I have a personal question.
> Why aren't they codes in the include/linux/ratelimit.h ?
>

Ah, They are originally in kernel.h . Sorry.

>
> Thanks.
> Naohiro Ooiwa
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/