diff --git a/include/linux/kernel.h b/include/linux/kernel.h index f4e3184fa054..3fa4c590cf12 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -15,7 +15,6 @@ #include #include #include -#include #include #include #include @@ -241,8 +240,8 @@ asmlinkage int vprintk(const char *fmt, va_list args) asmlinkage int printk(const char * fmt, ...) __attribute__ ((format (printf, 1, 2))) __cold; -extern struct ratelimit_state printk_ratelimit_state; -extern int printk_ratelimit(void); +extern int __printk_ratelimit(const char *func); +#define printk_ratelimit() __printk_ratelimit(__func__) extern bool printk_timed_ratelimit(unsigned long *caller_jiffies, unsigned int interval_msec); diff --git a/include/linux/net.h b/include/linux/net.h index 529a0931711d..d7e26e30c8c2 100644 --- a/include/linux/net.h +++ b/include/linux/net.h @@ -358,6 +358,7 @@ static const struct proto_ops name##_ops = { \ #ifdef CONFIG_SYSCTL #include +#include extern struct ratelimit_state net_ratelimit_state; #endif diff --git a/include/linux/ratelimit.h b/include/linux/ratelimit.h index 00044b856453..668cf1bef030 100644 --- a/include/linux/ratelimit.h +++ b/include/linux/ratelimit.h @@ -1,20 +1,31 @@ #ifndef _LINUX_RATELIMIT_H #define _LINUX_RATELIMIT_H -#include -#define DEFAULT_RATELIMIT_INTERVAL (5 * HZ) -#define DEFAULT_RATELIMIT_BURST 10 +#include +#include + +#define DEFAULT_RATELIMIT_INTERVAL (5 * HZ) +#define DEFAULT_RATELIMIT_BURST 10 struct ratelimit_state { - int interval; - int burst; - int printed; - int missed; - unsigned long begin; + spinlock_t lock; /* protect the state */ + + int interval; + int burst; + int printed; + int missed; + unsigned long begin; }; -#define DEFINE_RATELIMIT_STATE(name, interval, burst) \ - struct ratelimit_state name = {interval, burst,} +#define DEFINE_RATELIMIT_STATE(name, interval_init, burst_init) \ + \ + struct ratelimit_state name = { \ + .lock = __SPIN_LOCK_UNLOCKED(name.lock), \ + .interval = interval_init, \ + .burst = burst_init, \ + } -extern int __ratelimit(struct ratelimit_state *rs); -#endif +extern int ___ratelimit(struct ratelimit_state *rs, const char *func); +#define __ratelimit(state) ___ratelimit(state, __func__) + +#endif /* _LINUX_RATELIMIT_H */ diff --git a/kernel/printk.c b/kernel/printk.c index f38b07f78a4e..b5ac4d99c667 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -33,6 +33,7 @@ #include #include #include +#include #include @@ -1376,11 +1377,11 @@ late_initcall(disable_boot_consoles); */ DEFINE_RATELIMIT_STATE(printk_ratelimit_state, 5 * HZ, 10); -int printk_ratelimit(void) +int __printk_ratelimit(const char *func) { - return __ratelimit(&printk_ratelimit_state); + return ___ratelimit(&printk_ratelimit_state, func); } -EXPORT_SYMBOL(printk_ratelimit); +EXPORT_SYMBOL(__printk_ratelimit); /** * printk_timed_ratelimit - caller-controlled printk ratelimiting diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 0d949c517412..4dbf93a52ee9 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -36,6 +36,7 @@ #include #include #include +#include #include #include #include @@ -158,6 +159,8 @@ extern int no_unaligned_warning; extern int unaligned_dump_stack; #endif +extern struct ratelimit_state printk_ratelimit_state; + #ifdef CONFIG_RT_MUTEXES extern int max_lock_depth; #endif diff --git a/lib/ratelimit.c b/lib/ratelimit.c index 26187edcc7ea..09f5ce1810dc 100644 --- a/lib/ratelimit.c +++ b/lib/ratelimit.c @@ -7,15 +7,12 @@ * parameter. Now every user can use their own standalone ratelimit_state. * * This file is released under the GPLv2. - * */ -#include +#include #include #include -static DEFINE_SPINLOCK(ratelimit_lock); - /* * __ratelimit - rate limiting * @rs: ratelimit_state data @@ -23,35 +20,43 @@ static DEFINE_SPINLOCK(ratelimit_lock); * This enforces a rate limit: not more than @rs->ratelimit_burst callbacks * in every @rs->ratelimit_jiffies */ -int __ratelimit(struct ratelimit_state *rs) +int ___ratelimit(struct ratelimit_state *rs, const char *func) { unsigned long flags; + int ret; if (!rs->interval) return 1; - spin_lock_irqsave(&ratelimit_lock, flags); + /* + * If we contend on this state's lock then almost + * by definition we are too busy to print a message, + * in addition to the one that will be printed by + * the entity that is holding the lock already: + */ + if (!spin_trylock_irqsave(&rs->lock, flags)) + return 1; + 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; + func, rs->missed); + rs->begin = 0; rs->printed = 0; - rs->missed = 0; + rs->missed = 0; } - if (rs->burst && rs->burst > rs->printed) - goto print; + if (rs->burst && rs->burst > rs->printed) { + rs->printed++; + ret = 1; + } else { + rs->missed++; + ret = 0; + } + spin_unlock_irqrestore(&rs->lock, flags); - rs->missed++; - spin_unlock_irqrestore(&ratelimit_lock, flags); - return 0; - -print: - rs->printed++; - spin_unlock_irqrestore(&ratelimit_lock, flags); - return 1; + return ret; } -EXPORT_SYMBOL(__ratelimit); +EXPORT_SYMBOL(___ratelimit); diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c index 7db1de0497c6..887c03c4e3c6 100644 --- a/net/core/sysctl_net_core.c +++ b/net/core/sysctl_net_core.c @@ -10,7 +10,9 @@ #include #include #include +#include #include + #include #include diff --git a/net/core/utils.c b/net/core/utils.c index 83221aee7084..838250241d26 100644 --- a/net/core/utils.c +++ b/net/core/utils.c @@ -24,6 +24,8 @@ #include #include #include +#include + #include #include