printk ratelimiting rewrite
All ratelimit user use same jiffies and burst params, so some messages
(callbacks) will be lost.
For example:
a call printk_ratelimit(5 * HZ, 1)
b call printk_ratelimit(5 * HZ, 1) before the 5*HZ timeout of a, then b will
will be supressed.
- rewrite __ratelimit, and use a ratelimit_state as parameter. Thanks for
hints from andrew.
- Add WARN_ON_RATELIMIT, update rcupreempt.h
- remove __printk_ratelimit
- use __ratelimit in net_ratelimit
Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "Paul E. McKenney" <paulmck@us.ibm.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>
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 5c4b125..fdbbf72 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -15,6 +15,7 @@
#include <linux/bitops.h>
#include <linux/log2.h>
#include <linux/typecheck.h>
+#include <linux/ratelimit.h>
#include <asm/byteorder.h>
#include <asm/bug.h>
@@ -189,11 +190,8 @@
asmlinkage int printk(const char * fmt, ...)
__attribute__ ((format (printf, 1, 2))) __cold;
-extern int printk_ratelimit_jiffies;
-extern int printk_ratelimit_burst;
+extern struct ratelimit_state printk_ratelimit_state;
extern int printk_ratelimit(void);
-extern int __ratelimit(int ratelimit_jiffies, int ratelimit_burst);
-extern int __printk_ratelimit(int ratelimit_jiffies, int ratelimit_burst);
extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
unsigned int interval_msec);
#else
@@ -204,8 +202,6 @@
__attribute__ ((format (printf, 1, 2)));
static inline int __cold printk(const char *s, ...) { return 0; }
static inline int printk_ratelimit(void) { return 0; }
-static inline int __printk_ratelimit(int ratelimit_jiffies, \
- int ratelimit_burst) { return 0; }
static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \
unsigned int interval_msec) \
{ return false; }
diff --git a/include/linux/net.h b/include/linux/net.h
index 2f999fb..4a9a30f 100644
--- a/include/linux/net.h
+++ b/include/linux/net.h
@@ -351,8 +351,7 @@
#ifdef CONFIG_SYSCTL
#include <linux/sysctl.h>
-extern int net_msg_cost;
-extern int net_msg_burst;
+extern struct ratelimit_state net_ratelimit_state;
#endif
#endif /* __KERNEL__ */
diff --git a/include/linux/ratelimit.h b/include/linux/ratelimit.h
new file mode 100644
index 0000000..18a5b9b
--- /dev/null
+++ b/include/linux/ratelimit.h
@@ -0,0 +1,27 @@
+#ifndef _LINUX_RATELIMIT_H
+#define _LINUX_RATELIMIT_H
+#include <linux/param.h>
+
+#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;
+};
+
+#define DEFINE_RATELIMIT_STATE(name, interval, burst) \
+ struct ratelimit_state name = {interval, burst,}
+
+extern int __ratelimit(struct ratelimit_state *rs);
+
+static inline int ratelimit(void)
+{
+ static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL,
+ DEFAULT_RATELIMIT_BURST);
+ return __ratelimit(&rs);
+}
+#endif
diff --git a/include/linux/rcupreempt.h b/include/linux/rcupreempt.h
index f04b64e..0967f03 100644
--- a/include/linux/rcupreempt.h
+++ b/include/linux/rcupreempt.h
@@ -115,16 +115,21 @@
static inline void rcu_enter_nohz(void)
{
+ static DEFINE_RATELIMIT_STATE(rs, 10 * HZ, 1);
+
smp_mb(); /* CPUs seeing ++ must see prior RCU read-side crit sects */
__get_cpu_var(rcu_dyntick_sched).dynticks++;
- WARN_ON(__get_cpu_var(rcu_dyntick_sched).dynticks & 0x1);
+ WARN_ON_RATELIMIT(__get_cpu_var(rcu_dyntick_sched).dynticks & 0x1, &rs);
}
static inline void rcu_exit_nohz(void)
{
+ static DEFINE_RATELIMIT_STATE(rs, 10 * HZ, 1);
+
smp_mb(); /* CPUs seeing ++ must see later RCU read-side crit sects */
__get_cpu_var(rcu_dyntick_sched).dynticks++;
- WARN_ON(!(__get_cpu_var(rcu_dyntick_sched).dynticks & 0x1));
+ WARN_ON_RATELIMIT(!(__get_cpu_var(rcu_dyntick_sched).dynticks & 0x1),
+ &rs);
}
#else /* CONFIG_NO_HZ */