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>
This commit is contained in:
Joe Perches 2013-10-26 20:41:53 -07:00 коммит произвёл Greg Kroah-Hartman
Родитель 9d3bd76846
Коммит 29fc2bc753
1 изменённых файлов: 15 добавлений и 1 удалений

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@ -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