summaryrefslogtreecommitdiff
path: root/include/linux/printk.h
diff options
context:
space:
mode:
authorTanner Love <tannerlove@google.com>2021-06-28 16:50:06 +0300
committerDavid S. Miller <davem@davemloft.net>2021-06-29 01:54:57 +0300
commita358f40600b3b39ae3906b6118625b99c0aa7a34 (patch)
treeab09aec9e381aa45a20e183ab807890782b1c83a /include/linux/printk.h
parentb74ef9f9cb91fc86c642af965b7598c4df1c9922 (diff)
downloadlinux-a358f40600b3b39ae3906b6118625b99c0aa7a34.tar.xz
once: implement DO_ONCE_LITE for non-fast-path "do once" functionality
Certain uses of "do once" functionality reside outside of fast path, and so do not require jump label patching via static keys, making existing DO_ONCE undesirable in such cases. Replace uses of __section(".data.once") with DO_ONCE_LITE(_IF)? This patch changes the return values of xfs_printk_once, printk_once, and printk_deferred_once. Before, they returned whether the print was performed, but now, they always return true. This is okay because the return values of the following macros are entirely ignored throughout the kernel: - xfs_printk_once - xfs_warn_once - xfs_notice_once - xfs_info_once - printk_once - pr_emerg_once - pr_alert_once - pr_crit_once - pr_err_once - pr_warn_once - pr_notice_once - pr_info_once - pr_devel_once - pr_debug_once - printk_deferred_once - orc_warn Changes v3: - Expand commit message to explain why changing return values of xfs_printk_once, printk_once, printk_deferred_once is benign v2: - Fix i386 build warnings Signed-off-by: Tanner Love <tannerlove@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Acked-by: Mahesh Bandewar <maheshb@google.com> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/linux/printk.h')
-rw-r--r--include/linux/printk.h23
1 files changed, 3 insertions, 20 deletions
diff --git a/include/linux/printk.h b/include/linux/printk.h
index fe7eb2351610..885379a1c9a1 100644
--- a/include/linux/printk.h
+++ b/include/linux/printk.h
@@ -8,6 +8,7 @@
#include <linux/linkage.h>
#include <linux/cache.h>
#include <linux/ratelimit_types.h>
+#include <linux/once_lite.h>
extern const char linux_banner[];
extern const char linux_proc_banner[];
@@ -436,27 +437,9 @@ extern int kptr_restrict;
#ifdef CONFIG_PRINTK
#define printk_once(fmt, ...) \
-({ \
- static bool __section(".data.once") __print_once; \
- bool __ret_print_once = !__print_once; \
- \
- if (!__print_once) { \
- __print_once = true; \
- printk(fmt, ##__VA_ARGS__); \
- } \
- unlikely(__ret_print_once); \
-})
+ DO_ONCE_LITE(printk, fmt, ##__VA_ARGS__)
#define printk_deferred_once(fmt, ...) \
-({ \
- static bool __section(".data.once") __print_once; \
- bool __ret_print_once = !__print_once; \
- \
- if (!__print_once) { \
- __print_once = true; \
- printk_deferred(fmt, ##__VA_ARGS__); \
- } \
- unlikely(__ret_print_once); \
-})
+ DO_ONCE_LITE(printk_deferred, fmt, ##__VA_ARGS__)
#else
#define printk_once(fmt, ...) \
no_printk(fmt, ##__VA_ARGS__)