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>

1 files changed, 2 insertions, 2 deletions

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 1a8299d1fe59..35a50db9b6ce 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -624,7 +624,7 @@ static struct ctl_table kern_table[] = {
         {
                 .ctl_name       = KERN_PRINTK_RATELIMIT,
                 .procname       = "printk_ratelimit",
-                .data           = &printk_ratelimit_jiffies,
+                .data           = &printk_ratelimit_state.interval,
                 .maxlen         = sizeof(int),
                 .mode           = 0644,
                 .proc_handler   = &proc_dointvec_jiffies,
@@ -633,7 +633,7 @@ static struct ctl_table kern_table[] = {
         {
                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
                 .procname       = "printk_ratelimit_burst",
-                .data           = &printk_ratelimit_burst,
+                .data           = &printk_ratelimit_state.burst,
                 .maxlen         = sizeof(int),
                 .mode           = 0644,
                 .proc_handler   = &proc_dointvec,