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| author | Paul Gortmaker <paul.gortmaker@windriver.com> | 2019-04-13 05:11:31 +0300 |
|---|---|---|
| committer | Petr Mladek <pmladek@suse.com> | 2019-04-15 11:23:53 +0300 |
| commit | 3ec25826ae33618a03c28235af8d62e8a7f7f15f (patch) | |
| tree | 142911824661921ae29ccc96d894c2e6e3782dc8 | |
| parent | 2821fd0c2be0c4e513b1622d86df9170ef62a6d4 (diff) | |
| download | linux-3ec25826ae33618a03c28235af8d62e8a7f7f15f.tar.xz | |
printk: Tie printk_once / printk_deferred_once into .data.once for reset
In commit b1fca27d384e ("kernel debug: support resetting WARN*_ONCE")
we got the opportunity to reset state on the one shot messages,
without having to reboot.
However printk_once (printk_deferred_once) live in a different file
and didn't get the same kind of update/conversion, so they remain
unconditionally one shot, until the system is rebooted.
For example, we currently have:
sched/rt.c: printk_deferred_once("sched: RT throttling activated\n");
..which could reasonably be tripped as someone is testing and tuning
a new system/workload and their task placements. For consistency, and
to avoid reboots in the same vein as the original commit, we make these
two instances of _once the same as the WARN*_ONCE instances are.
Link: http://lkml.kernel.org/r/1555121491-31213-1-git-send-email-paul.gortmaker@windriver.com
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
| -rw-r--r-- | Documentation/clearing-warn-once.txt | 2 | ||||
| -rw-r--r-- | include/linux/printk.h | 4 |
2 files changed, 3 insertions, 3 deletions
diff --git a/Documentation/clearing-warn-once.txt b/Documentation/clearing-warn-once.txt index 5b1f5d547be1..c68598b31428 100644 --- a/Documentation/clearing-warn-once.txt +++ b/Documentation/clearing-warn-once.txt @@ -1,5 +1,5 @@ -WARN_ONCE / WARN_ON_ONCE only print a warning once. +WARN_ONCE / WARN_ON_ONCE / printk_once only emit a message once. echo 1 > /sys/kernel/debug/clear_warn_once diff --git a/include/linux/printk.h b/include/linux/printk.h index d7c77ed1a4cb..84ea4d094af3 100644 --- a/include/linux/printk.h +++ b/include/linux/printk.h @@ -347,7 +347,7 @@ extern int kptr_restrict; #ifdef CONFIG_PRINTK #define printk_once(fmt, ...) \ ({ \ - static bool __print_once __read_mostly; \ + static bool __section(.data.once) __print_once; \ bool __ret_print_once = !__print_once; \ \ if (!__print_once) { \ @@ -358,7 +358,7 @@ extern int kptr_restrict; }) #define printk_deferred_once(fmt, ...) \ ({ \ - static bool __print_once __read_mostly; \ + static bool __section(.data.once) __print_once; \ bool __ret_print_once = !__print_once; \ \ if (!__print_once) { \ |