aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorMatt Mackall <mpm@selenic.com>2005-05-01 08:59:02 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-05-01 08:59:02 -0700
commitd59745ce3e7aa13856bca16d3bcbb95041775ff6 (patch)
tree6e495bb6697d86534685bf813c43e210a8d8323a
parentcd7619d6bf36564cf54ff7218ef54e558a741913 (diff)
[PATCH] clean up kernel messages
Arrange for all kernel printks to be no-ops. Only available if CONFIG_EMBEDDED. This patch saves about 375k on my laptop config and nearly 100k on minimal configs. Signed-off-by: Matt Mackall <mpm@selenic.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
-rw-r--r--arch/i386/kernel/head.S2
-rw-r--r--include/linux/kernel.h9
-rw-r--r--init/Kconfig11
-rw-r--r--kernel/printk.c27
4 files changed, 43 insertions, 6 deletions
diff --git a/arch/i386/kernel/head.S b/arch/i386/kernel/head.S
index d273fd746192..e966fc8c44c4 100644
--- a/arch/i386/kernel/head.S
+++ b/arch/i386/kernel/head.S
@@ -380,6 +380,7 @@ rp_sidt:
ALIGN
ignore_int:
cld
+#ifdef CONFIG_PRINTK
pushl %eax
pushl %ecx
pushl %edx
@@ -400,6 +401,7 @@ ignore_int:
popl %edx
popl %ecx
popl %eax
+#endif
iret
/*
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 7c1cba4a5278..e25b97062ce1 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -115,10 +115,19 @@ extern int __kernel_text_address(unsigned long addr);
extern int kernel_text_address(unsigned long addr);
extern int session_of_pgrp(int pgrp);
+#ifdef CONFIG_PRINTK
asmlinkage int vprintk(const char *fmt, va_list args)
__attribute__ ((format (printf, 1, 0)));
asmlinkage int printk(const char * fmt, ...)
__attribute__ ((format (printf, 1, 2)));
+#else
+static inline int vprintk(const char *s, va_list args)
+ __attribute__ ((format (printf, 1, 0)));
+static inline int vprintk(const char *s, va_list args) { return 0; }
+static inline int printk(const char *s, ...)
+ __attribute__ ((format (printf, 1, 2)));
+static inline int printk(const char *s, ...) { return 0; }
+#endif
unsigned long int_sqrt(unsigned long);
diff --git a/init/Kconfig b/init/Kconfig
index 42dca393b94e..40d286d1d118 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -275,6 +275,17 @@ config KALLSYMS_EXTRA_PASS
reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while
you wait for kallsyms to be fixed.
+
+config PRINTK
+ default y
+ bool "Enable support for printk" if EMBEDDED
+ help
+ This option enables normal printk support. Removing it
+ eliminates most of the message strings from the kernel image
+ and makes the kernel more or less silent. As this makes it
+ very difficult to diagnose system problems, saying N here is
+ strongly discouraged.
+
config BUG
bool "BUG() support" if EMBEDDED
default y
diff --git a/kernel/printk.c b/kernel/printk.c
index 1498689548d1..290a07ce2c8a 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -85,10 +85,6 @@ static int console_locked;
*/
static DEFINE_SPINLOCK(logbuf_lock);
-static char __log_buf[__LOG_BUF_LEN];
-static char *log_buf = __log_buf;
-static int log_buf_len = __LOG_BUF_LEN;
-
#define LOG_BUF_MASK (log_buf_len-1)
#define LOG_BUF(idx) (log_buf[(idx) & LOG_BUF_MASK])
@@ -99,7 +95,6 @@ static int log_buf_len = __LOG_BUF_LEN;
static unsigned long log_start; /* Index into log_buf: next char to be read by syslog() */
static unsigned long con_start; /* Index into log_buf: next char to be sent to consoles */
static unsigned long log_end; /* Index into log_buf: most-recently-written-char + 1 */
-static unsigned long logged_chars; /* Number of chars produced since last read+clear operation */
/*
* Array of consoles built from command line options (console=)
@@ -120,6 +115,13 @@ static int preferred_console = -1;
/* Flag: console code may call schedule() */
static int console_may_schedule;
+#ifdef CONFIG_PRINTK
+
+static char __log_buf[__LOG_BUF_LEN];
+static char *log_buf = __log_buf;
+static int log_buf_len = __LOG_BUF_LEN;
+static unsigned long logged_chars; /* Number of chars produced since last read+clear operation */
+
/*
* Setup a list of consoles. Called from init/main.c
*/
@@ -535,6 +537,7 @@ __setup("time", printk_time_setup);
* then changes console_loglevel may break. This is because console_loglevel
* is inspected when the actual printing occurs.
*/
+
asmlinkage int printk(const char *fmt, ...)
{
va_list args;
@@ -655,6 +658,18 @@ out:
EXPORT_SYMBOL(printk);
EXPORT_SYMBOL(vprintk);
+#else
+
+asmlinkage long sys_syslog(int type, char __user * buf, int len)
+{
+ return 0;
+}
+
+int do_syslog(int type, char __user * buf, int len) { return 0; }
+static void call_console_drivers(unsigned long start, unsigned long end) {}
+
+#endif
+
/**
* acquire_console_sem - lock the console system for exclusive use.
*
@@ -931,7 +946,7 @@ int unregister_console(struct console * console)
return res;
}
EXPORT_SYMBOL(unregister_console);
-
+
/**
* tty_write_message - write a message to a certain tty, not just the console.
*

Privacy Policy