From 28e1745b9fa23f71f465f6b65f966a1ef65af517 Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Tue, 23 Mar 2021 15:42:01 +0100 Subject: [PATCH] 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 : 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: https://lore.kernel.org/r/20210323144201.486050-1-linux@rasmusvillemoes.dk --- kernel/printk/internal.h | 3 --- kernel/printk/printk.c | 8 +------- kernel/printk/printk_safe.c | 3 ++- 3 files changed, 3 insertions(+), 11 deletions(-) diff --git a/kernel/printk/internal.h b/kernel/printk/internal.h index e7acc2888c8e..51615c909b2f 100644 --- a/kernel/printk/internal.h +++ b/kernel/printk/internal.h @@ -19,7 +19,6 @@ int vprintk_store(int facility, int level, __printf(1, 0) int vprintk_default(const char *fmt, va_list args); __printf(1, 0) int vprintk_deferred(const char *fmt, va_list args); -__printf(1, 0) int vprintk_func(const char *fmt, va_list args); void __printk_safe_enter(void); void __printk_safe_exit(void); @@ -54,8 +53,6 @@ void defer_console_output(void); #else -__printf(1, 0) int vprintk_func(const char *fmt, va_list args) { return 0; } - /* * In !PRINTK builds we still export console_sem * semaphore and some of console functions (console_unlock()/etc.), so diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 2f829fbf0a13..45ae60f3e489 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -2180,12 +2180,6 @@ asmlinkage int vprintk_emit(int facility, int level, } EXPORT_SYMBOL(vprintk_emit); -asmlinkage int vprintk(const char *fmt, va_list args) -{ - return vprintk_func(fmt, args); -} -EXPORT_SYMBOL(vprintk); - int vprintk_default(const char *fmt, va_list args) { return vprintk_emit(0, LOGLEVEL_DEFAULT, NULL, fmt, args); @@ -2219,7 +2213,7 @@ asmlinkage __visible int printk(const char *fmt, ...) int r; va_start(args, fmt); - r = vprintk_func(fmt, args); + r = vprintk(fmt, args); va_end(args); return r; 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) this_cpu_dec(printk_context); } -__printf(1, 0) int vprintk_func(const char *fmt, va_list args) +asmlinkage int vprintk(const char *fmt, va_list args) { #ifdef CONFIG_KGDB_KDB /* 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. */ printk_safe_flush(); } +EXPORT_SYMBOL(vprintk);