Merge branch 'core-printk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-printk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
ratelimit: Make suppressed output messages more useful
printk: Remove ratelimit.h from kernel.h
ratelimit: Fix/allow use in atomic contexts
ratelimit: Use per ratelimit context locking
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index f4e3184..3fa4c59 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -15,7 +15,6 @@
#include <linux/bitops.h>
#include <linux/log2.h>
#include <linux/typecheck.h>
-#include <linux/ratelimit.h>
#include <linux/dynamic_debug.h>
#include <asm/byteorder.h>
#include <asm/bug.h>
@@ -241,8 +240,8 @@
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 529a093..d7e26e3 100644
--- a/include/linux/net.h
+++ b/include/linux/net.h
@@ -358,6 +358,7 @@
#ifdef CONFIG_SYSCTL
#include <linux/sysctl.h>
+#include <linux/ratelimit.h>
extern struct ratelimit_state net_ratelimit_state;
#endif
diff --git a/include/linux/ratelimit.h b/include/linux/ratelimit.h
index 00044b8..668cf1b 100644
--- a/include/linux/ratelimit.h
+++ b/include/linux/ratelimit.h
@@ -1,20 +1,31 @@
#ifndef _LINUX_RATELIMIT_H
#define _LINUX_RATELIMIT_H
-#include <linux/param.h>
-#define DEFAULT_RATELIMIT_INTERVAL (5 * HZ)
-#define DEFAULT_RATELIMIT_BURST 10
+#include <linux/param.h>
+#include <linux/spinlock_types.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;
+ 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 f38b07f..b5ac4d9 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -33,6 +33,7 @@
#include <linux/bootmem.h>
#include <linux/syscalls.h>
#include <linux/kexec.h>
+#include <linux/ratelimit.h>
#include <asm/uaccess.h>
@@ -1376,11 +1377,11 @@
*/
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 0d949c5..4dbf93a 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -36,6 +36,7 @@
#include <linux/sysrq.h>
#include <linux/highuid.h>
#include <linux/writeback.h>
+#include <linux/ratelimit.h>
#include <linux/hugetlb.h>
#include <linux/initrd.h>
#include <linux/key.h>
@@ -158,6 +159,8 @@
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 26187ed..09f5ce1 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 <linux/kernel.h>
+#include <linux/ratelimit.h>
#include <linux/jiffies.h>
#include <linux/module.h>
-static DEFINE_SPINLOCK(ratelimit_lock);
-
/*
* __ratelimit - rate limiting
* @rs: ratelimit_state data
@@ -23,35 +20,43 @@
* 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 7db1de0..887c03c 100644
--- a/net/core/sysctl_net_core.c
+++ b/net/core/sysctl_net_core.c
@@ -10,7 +10,9 @@
#include <linux/module.h>
#include <linux/socket.h>
#include <linux/netdevice.h>
+#include <linux/ratelimit.h>
#include <linux/init.h>
+
#include <net/ip.h>
#include <net/sock.h>
diff --git a/net/core/utils.c b/net/core/utils.c
index 83221ae..8382502 100644
--- a/net/core/utils.c
+++ b/net/core/utils.c
@@ -24,6 +24,8 @@
#include <linux/types.h>
#include <linux/percpu.h>
#include <linux/init.h>
+#include <linux/ratelimit.h>
+
#include <net/sock.h>
#include <asm/byteorder.h>