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 <geert@linux-m68k.org>
Acked-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/init/Kconfig b/init/Kconfig
index 1c505e0..3ee28ae 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -838,6 +838,7 @@
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 7a6e694..a4436b0 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -267,7 +267,6 @@
#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 @@
}
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 @@
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)
{