Re: [PATCH] kernel.h: Add printk_ratelimited and pr__rl

Naohiro Ooiwa
2009-11-05T14:16:07Z

Ingo Molnar wrote:
> * Joe Perches <joe@perches.com> 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@perches.com>
>>
>> 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 ?

Thanks.
Naohiro Ooiwa