mirror of
https://github.com/torvalds/linux.git
synced 2024-11-27 06:31:52 +00:00
4d9c377c81
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Dave Young <hidave.darkstar@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
58 lines
1.3 KiB
C
58 lines
1.3 KiB
C
/*
|
|
* ratelimit.c - Do something with rate limit.
|
|
*
|
|
* Isolated from kernel/printk.c by Dave Young <hidave.darkstar@gmail.com>
|
|
*
|
|
* 2008-05-01 rewrite the function and use a ratelimit_state data struct as
|
|
* parameter. Now every user can use their own standalone ratelimit_state.
|
|
*
|
|
* This file is released under the GPLv2.
|
|
*
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/jiffies.h>
|
|
#include <linux/module.h>
|
|
|
|
static DEFINE_SPINLOCK(ratelimit_lock);
|
|
|
|
/*
|
|
* __ratelimit - rate limiting
|
|
* @rs: ratelimit_state data
|
|
*
|
|
* This enforces a rate limit: not more than @rs->ratelimit_burst callbacks
|
|
* in every @rs->ratelimit_jiffies
|
|
*/
|
|
int __ratelimit(struct ratelimit_state *rs)
|
|
{
|
|
unsigned long flags;
|
|
|
|
if (!rs->interval)
|
|
return 1;
|
|
|
|
spin_lock_irqsave(&ratelimit_lock, flags);
|
|
if (!rs->begin)
|
|
rs->begin = jiffies;
|
|
|
|
if (time_is_before_jiffies(rs->begin + rs->interval)) {
|
|
if (rs->missed)
|
|
printk(KERN_WARNING "%s: %d callbacks suppressed\n",
|
|
__func__, rs->missed);
|
|
rs->begin = 0;
|
|
rs->printed = 0;
|
|
rs->missed = 0;
|
|
}
|
|
if (rs->burst && rs->burst > rs->printed)
|
|
goto print;
|
|
|
|
rs->missed++;
|
|
spin_unlock_irqrestore(&ratelimit_lock, flags);
|
|
return 0;
|
|
|
|
print:
|
|
rs->printed++;
|
|
spin_unlock_irqrestore(&ratelimit_lock, flags);
|
|
return 1;
|
|
}
|
|
EXPORT_SYMBOL(__ratelimit);
|