diff options
| author | Andrew Morton <akpm@osdl.org> | 2006-11-02 22:07:16 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-11-03 12:27:58 -0800 |
| commit | f46c483357c2d87606bbefb511321e3efd4baae0 (patch) | |
| tree | e3276379337a56353cce051d8f7efbc87dc61fdb | |
| parent | 7f6b8876c7e66b0d15af134e2a5b87e55514eb6d (diff) | |
[PATCH] Add printk_timed_ratelimit()
printk_ratelimit() has global state which makes it not useful for callers
which wish to perform ratelimiting at a particular frequency.
Add a printk_timed_ratelimit() which utilises caller-provided state storage to
permit more flexibility.
This function can in fact be used for things other than printk ratelimiting
and is perhaps poorly named.
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
| -rw-r--r-- | include/linux/kernel.h | 2 | ||||
| -rw-r--r-- | kernel/printk.c | 21 |
2 files changed, 23 insertions, 0 deletions
diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 80f39cab470a..24b611147adb 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -171,6 +171,8 @@ __attribute_const__ roundup_pow_of_two(unsigned long x) extern int printk_ratelimit(void); extern int __printk_ratelimit(int ratelimit_jiffies, int ratelimit_burst); +extern bool printk_timed_ratelimit(unsigned long *caller_jiffies, + unsigned int interval_msec); static inline void console_silent(void) { diff --git a/kernel/printk.c b/kernel/printk.c index f7d427ef5038..66426552fbfe 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -31,6 +31,7 @@ #include <linux/security.h> #include <linux/bootmem.h> #include <linux/syscalls.h> +#include <linux/jiffies.h> #include <asm/uaccess.h> @@ -1101,3 +1102,23 @@ int printk_ratelimit(void) printk_ratelimit_burst); } EXPORT_SYMBOL(printk_ratelimit); + +/** + * printk_timed_ratelimit - caller-controlled printk ratelimiting + * @caller_jiffies: pointer to caller's state + * @interval_msecs: minimum interval between prints + * + * printk_timed_ratelimit() returns true if more than @interval_msecs + * milliseconds have elapsed since the last time printk_timed_ratelimit() + * returned true. + */ +bool printk_timed_ratelimit(unsigned long *caller_jiffies, + unsigned int interval_msecs) +{ + if (*caller_jiffies == 0 || time_after(jiffies, *caller_jiffies)) { + *caller_jiffies = jiffies + msecs_to_jiffies(interval_msecs); + return true; + } + return false; +} +EXPORT_SYMBOL(printk_timed_ratelimit); |