diff options
Diffstat (limited to 'lib/ratelimit.c')
-rw-r--r-- | lib/ratelimit.c | 45 |
1 files changed, 25 insertions, 20 deletions
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 @@ | |||
7 | * parameter. Now every user can use their own standalone ratelimit_state. | 7 | * parameter. Now every user can use their own standalone ratelimit_state. |
8 | * | 8 | * |
9 | * This file is released under the GPLv2. | 9 | * This file is released under the GPLv2. |
10 | * | ||
11 | */ | 10 | */ |
12 | 11 | ||
13 | #include <linux/kernel.h> | 12 | #include <linux/ratelimit.h> |
14 | #include <linux/jiffies.h> | 13 | #include <linux/jiffies.h> |
15 | #include <linux/module.h> | 14 | #include <linux/module.h> |
16 | 15 | ||
17 | static DEFINE_SPINLOCK(ratelimit_lock); | ||
18 | |||
19 | /* | 16 | /* |
20 | * __ratelimit - rate limiting | 17 | * __ratelimit - rate limiting |
21 | * @rs: ratelimit_state data | 18 | * @rs: ratelimit_state data |
@@ -23,35 +20,43 @@ static DEFINE_SPINLOCK(ratelimit_lock); | |||
23 | * This enforces a rate limit: not more than @rs->ratelimit_burst callbacks | 20 | * This enforces a rate limit: not more than @rs->ratelimit_burst callbacks |
24 | * in every @rs->ratelimit_jiffies | 21 | * in every @rs->ratelimit_jiffies |
25 | */ | 22 | */ |
26 | int __ratelimit(struct ratelimit_state *rs) | 23 | int ___ratelimit(struct ratelimit_state *rs, const char *func) |
27 | { | 24 | { |
28 | unsigned long flags; | 25 | unsigned long flags; |
26 | int ret; | ||
29 | 27 | ||
30 | if (!rs->interval) | 28 | if (!rs->interval) |
31 | return 1; | 29 | return 1; |
32 | 30 | ||
33 | spin_lock_irqsave(&ratelimit_lock, flags); | 31 | /* |
32 | * If we contend on this state's lock then almost | ||
33 | * by definition we are too busy to print a message, | ||
34 | * in addition to the one that will be printed by | ||
35 | * the entity that is holding the lock already: | ||
36 | */ | ||
37 | if (!spin_trylock_irqsave(&rs->lock, flags)) | ||
38 | return 1; | ||
39 | |||
34 | if (!rs->begin) | 40 | if (!rs->begin) |
35 | rs->begin = jiffies; | 41 | rs->begin = jiffies; |
36 | 42 | ||
37 | if (time_is_before_jiffies(rs->begin + rs->interval)) { | 43 | if (time_is_before_jiffies(rs->begin + rs->interval)) { |
38 | if (rs->missed) | 44 | if (rs->missed) |
39 | printk(KERN_WARNING "%s: %d callbacks suppressed\n", | 45 | printk(KERN_WARNING "%s: %d callbacks suppressed\n", |
40 | __func__, rs->missed); | 46 | func, rs->missed); |
41 | rs->begin = 0; | 47 | rs->begin = 0; |
42 | rs->printed = 0; | 48 | rs->printed = 0; |
43 | rs->missed = 0; | 49 | rs->missed = 0; |
44 | } | 50 | } |
45 | if (rs->burst && rs->burst > rs->printed) | 51 | if (rs->burst && rs->burst > rs->printed) { |
46 | goto print; | 52 | rs->printed++; |
47 | 53 | ret = 1; | |
48 | rs->missed++; | 54 | } else { |
49 | spin_unlock_irqrestore(&ratelimit_lock, flags); | 55 | rs->missed++; |
50 | return 0; | 56 | ret = 0; |
57 | } | ||
58 | spin_unlock_irqrestore(&rs->lock, flags); | ||
51 | 59 | ||
52 | print: | 60 | return ret; |
53 | rs->printed++; | ||
54 | spin_unlock_irqrestore(&ratelimit_lock, flags); | ||
55 | return 1; | ||
56 | } | 61 | } |
57 | EXPORT_SYMBOL(__ratelimit); | 62 | EXPORT_SYMBOL(___ratelimit); |