From 29fc2bc75393864bbc9b90a7a13a0d0e11c6f41e Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Sat, 26 Oct 2013 20:41:53 -0700 Subject: [PATCH] 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 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__ratelimited functions must also have another specific #include . Most users have this done indirectly via #include printk.h may not #include as it causes circular dependencies and compilation failures. Signed-off-by: Joe Perches Tested-by: Krzysztof Mazur Signed-off-by: Greg Kroah-Hartman --- include/linux/printk.h | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) 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 + /* 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 -- 2.30.2