diff options
| author | Joe Perches <joe@perches.com> | 2013-10-27 07:41:53 +0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-10-30 03:50:52 +0400 |
| commit | 29fc2bc75393864bbc9b90a7a13a0d0e11c6f41e (patch) | |
| tree | c01b58e6f7bc61d12e1d1d1eeb036da31ea0ab6d /include/linux/printk.h | |
| parent | 9d3bd7684645834ede59d285af1d70ccabee9bf3 (diff) | |
| download | linux-29fc2bc75393864bbc9b90a7a13a0d0e11c6f41e.tar.xz | |
printk: pr_debug_ratelimited: check state first to reduce "callbacks suppressed" messages
pr_debug_ratelimited should be coded similarly to dev_dbg_ratelimited
to reduce the "callbacks suppressed" messages.
Add #include <linux/dynamic_debug.h> to printk.h. Unfortunately, this
new #include must be after the prototype/declaration of function printk.
It may be better to split out these _ratelimited declarations into
a separate file one day.
Any use of these pr_<foo>_ratelimited functions must also have another
specific #include <ratelimited.h>. Most users have this done indirectly
via #include <linux/kernel.h>
printk.h may not #include <linux/ratelimit.h> as it causes circular
dependencies and compilation failures.
Signed-off-by: Joe Perches <joe@perches.com>
Tested-by: Krzysztof Mazur <krzysiek@podlesie.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux/printk.h')
| -rw-r--r-- | include/linux/printk.h | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/include/linux/printk.h b/include/linux/printk.h index e6131a782481..694925837a16 100644 --- a/include/linux/printk.h +++ b/include/linux/printk.h @@ -233,6 +233,8 @@ extern asmlinkage void dump_stack(void) __cold; no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) #endif +#include <linux/dynamic_debug.h> + /* If you are writing a driver, please use dev_dbg instead */ #if defined(CONFIG_DYNAMIC_DEBUG) /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */ @@ -343,7 +345,19 @@ extern asmlinkage void dump_stack(void) __cold; #endif /* If you are writing a driver, please use dev_dbg instead */ -#if defined(DEBUG) +#if defined(CONFIG_DYNAMIC_DEBUG) +/* descriptor check is first to prevent flooding with "callbacks suppressed" */ +#define pr_debug_ratelimited(fmt, ...) \ +do { \ + static DEFINE_RATELIMIT_STATE(_rs, \ + DEFAULT_RATELIMIT_INTERVAL, \ + DEFAULT_RATELIMIT_BURST); \ + DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt); \ + if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) && \ + __ratelimit(&_rs)) \ + __dynamic_pr_debug(&descriptor, fmt, ##__VA_ARGS__); \ +} while (0) +#elif defined(DEBUG) #define pr_debug_ratelimited(fmt, ...) \ printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) #else |