From 2240a31db67582468e2f7a5a5962b7d0ffaaa6a4 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Mon, 13 Oct 2014 15:51:11 -0700 Subject: [PATCH] printk: don't bother using LOG_CPU_MAX_BUF_SHIFT on !SMP When configuring a uniprocessor kernel, don't bother the user with an irrelevant LOG_CPU_MAX_BUF_SHIFT question, and don't build the unused code. Signed-off-by: Geert Uytterhoeven Acked-by: Luis R. Rodriguez Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- init/Kconfig | 1 + kernel/printk/printk.c | 7 ++++++- 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/init/Kconfig b/init/Kconfig index 1c505e090422..3ee28ae02cc8 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -838,6 +838,7 @@ config LOG_BUF_SHIFT config LOG_CPU_MAX_BUF_SHIFT int "CPU kernel log buffer size contribution (13 => 8 KB, 17 => 128KB)" + depends on SMP range 0 21 default 12 if !BASE_SMALL default 0 if BASE_SMALL diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 7a6e69441f75..a4436b0cf769 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -267,7 +267,6 @@ static u32 clear_idx; #define LOG_ALIGN __alignof__(struct printk_log) #endif #define __LOG_BUF_LEN (1 << CONFIG_LOG_BUF_SHIFT) -#define __LOG_CPU_MAX_BUF_LEN (1 << CONFIG_LOG_CPU_MAX_BUF_SHIFT) static char __log_buf[__LOG_BUF_LEN] __aligned(LOG_ALIGN); static char *log_buf = __log_buf; static u32 log_buf_len = __LOG_BUF_LEN; @@ -852,6 +851,9 @@ static int __init log_buf_len_setup(char *str) } early_param("log_buf_len", log_buf_len_setup); +#ifdef CONFIG_SMP +#define __LOG_CPU_MAX_BUF_LEN (1 << CONFIG_LOG_CPU_MAX_BUF_SHIFT) + static void __init log_buf_add_cpu(void) { unsigned int cpu_extra; @@ -878,6 +880,9 @@ static void __init log_buf_add_cpu(void) log_buf_len_update(cpu_extra + __LOG_BUF_LEN); } +#else /* !CONFIG_SMP */ +static inline void log_buf_add_cpu(void) {} +#endif /* CONFIG_SMP */ void __init setup_log_buf(int early) { -- 2.20.1