diff options
author | Borislav Petkov <bp@suse.de> | 2016-08-03 00:04:04 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-08-03 02:35:06 +0300 |
commit | 6b1d174b0c27b5de421eda55c2731f32b6bd9852 (patch) | |
tree | 3095928a9c579090ef8db9cb6df7125ec1c638db /include/linux/ratelimit.h | |
parent | b5644a153d2701ffc335cfb9ef49967bd5b6a3c2 (diff) | |
download | linux-6b1d174b0c27b5de421eda55c2731f32b6bd9852.tar.xz |
ratelimit: extend to print suppressed messages on release
Extend the ratelimiting facility to print the amount of suppressed lines
when it is being released.
This use case is aimed at short-termed, burst-like users for which we
want to output the suppressed lines stats only once, after it has been
disposed of. For an example, see /dev/kmsg usage in a follow-on patch.
Also, change the printk() line we issue on release to not use
"callbacks" as it is misleading: we're not suppressing callbacks but
printk() calls.
This has been separated from a previous patch by Linus.
Link: http://lkml.kernel.org/r/20160716061745.15795-2-bp@alien8.de
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Dave Young <dyoung@redhat.com>
Cc: Franck Bui <fbui@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/ratelimit.h')
-rw-r--r-- | include/linux/ratelimit.h | 38 |
1 files changed, 33 insertions, 5 deletions
diff --git a/include/linux/ratelimit.h b/include/linux/ratelimit.h index 18102529254e..57c9e0622a38 100644 --- a/include/linux/ratelimit.h +++ b/include/linux/ratelimit.h @@ -2,11 +2,15 @@ #define _LINUX_RATELIMIT_H #include <linux/param.h> +#include <linux/sched.h> #include <linux/spinlock.h> #define DEFAULT_RATELIMIT_INTERVAL (5 * HZ) #define DEFAULT_RATELIMIT_BURST 10 +/* issue num suppressed message on exit */ +#define RATELIMIT_MSG_ON_RELEASE BIT(0) + struct ratelimit_state { raw_spinlock_t lock; /* protect the state */ @@ -15,6 +19,7 @@ struct ratelimit_state { int printed; int missed; unsigned long begin; + unsigned long flags; }; #define RATELIMIT_STATE_INIT(name, interval_init, burst_init) { \ @@ -34,12 +39,35 @@ struct ratelimit_state { static inline void ratelimit_state_init(struct ratelimit_state *rs, int interval, int burst) { + memset(rs, 0, sizeof(*rs)); + raw_spin_lock_init(&rs->lock); - rs->interval = interval; - rs->burst = burst; - rs->printed = 0; - rs->missed = 0; - rs->begin = 0; + rs->interval = interval; + rs->burst = burst; +} + +static inline void ratelimit_default_init(struct ratelimit_state *rs) +{ + return ratelimit_state_init(rs, DEFAULT_RATELIMIT_INTERVAL, + DEFAULT_RATELIMIT_BURST); +} + +static inline void ratelimit_state_exit(struct ratelimit_state *rs) +{ + if (!(rs->flags & RATELIMIT_MSG_ON_RELEASE)) + return; + + if (rs->missed) { + pr_warn("%s: %d output lines suppressed due to ratelimiting\n", + current->comm, rs->missed); + rs->missed = 0; + } +} + +static inline void +ratelimit_set_flags(struct ratelimit_state *rs, unsigned long flags) +{ + rs->flags = flags; } extern struct ratelimit_state printk_ratelimit_state; |