path: root/kernel/printk/printk_safe.c
diff options
authorRasmus Villemoes <>2021-03-23 15:42:01 +0100
committerPetr Mladek <>2021-03-30 15:21:18 +0200
commit28e1745b9fa23f71f465f6b65f966a1ef65af517 (patch)
tree9e2e6d3c75df3d1574b72f6ac9bc0c6d77917a04 /kernel/printk/printk_safe.c
parent505a27a7342912f25ef3d9dabd6a08857e76efc2 (diff)
printk: rename vprintk_func to vprintk
The printk code is already hard enough to understand. Remove an unnecessary indirection by renaming vprintk_func to vprintk (adding the asmlinkage annotation), and removing the vprintk definition from printk.c. That way, printk is implemented in terms of vprintk as one would expect, and there's no "vprintk_func, what's that? Some function pointer that gets set where?" The declaration of vprintk in linux/printk.h already has the __printf(1,0) attribute, there's no point repeating that with the definition - it's for diagnostics in callers. linux/printk.h already contains a static inline {return 0;} definition of vprintk when !CONFIG_PRINTK. Since the corresponding stub definition of vprintk_func was not marked "static inline", any translation unit including internal.h would get a definition of vprintk_func - it just so happens that for !CONFIG_PRINTK, there is precisely one such TU, namely printk.c. Had there been more, it would be a link error; now it's just a silly waste of a few bytes of .text, which one must assume are rather precious to anyone disabling PRINTK. $ objdump -dr kernel/printk/printk.o 00000330 <vprintk_func>: 330: 31 c0 xor %eax,%eax 332: c3 ret 333: 8d b4 26 00 00 00 00 lea 0x0(%esi,%eiz,1),%esi 33a: 8d b6 00 00 00 00 lea 0x0(%esi),%esi Signed-off-by: Rasmus Villemoes <> Reviewed-by: Steven Rostedt (VMware) <> Reviewed-by: Petr Mladek <> Signed-off-by: Petr Mladek <> Link:
Diffstat (limited to 'kernel/printk/printk_safe.c')
1 files changed, 2 insertions, 1 deletions
diff --git a/kernel/printk/printk_safe.c b/kernel/printk/printk_safe.c
index bbf5c1993636..7a1414622051 100644
--- a/kernel/printk/printk_safe.c
+++ b/kernel/printk/printk_safe.c
@@ -357,7 +357,7 @@ void __printk_safe_exit(void)
-__printf(1, 0) int vprintk_func(const char *fmt, va_list args)
+asmlinkage int vprintk(const char *fmt, va_list args)
/* Allow to pass printk() to kdb but avoid a recursion. */
@@ -411,3 +411,4 @@ void __init printk_safe_init(void)
/* Flush pending messages that did not have scheduled IRQ works. */