Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[safe/jmp/linux-2.6] / kernel / printk.c

diff --git a/kernel/printk.c b/kernel/printk.c
index 668df35..f38b07f 100644 (file)
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -67,6 +67,8 @@ int console_printk[4] = {
        DEFAULT_CONSOLE_LOGLEVEL,       /* default_console_loglevel */
 };
 
+static int saved_console_loglevel = -1;
+
 /*
  * Low level drivers may need that to know if they can schedule in
  * their unblank() callback or not. So let's export it.
@@ -204,12 +206,11 @@ __setup("log_buf_len=", log_buf_len_setup);
 #ifdef CONFIG_BOOT_PRINTK_DELAY
 
 static unsigned int boot_delay; /* msecs delay after each printk during bootup */
-static unsigned long long printk_delay_msec; /* per msec, based on boot_delay */
+static unsigned long long loops_per_msec;      /* based on boot_delay */
 
 static int __init boot_delay_setup(char *str)
 {
        unsigned long lpj;
-       unsigned long long loops_per_msec;
 
        lpj = preset_lpj ? preset_lpj : 1000000;        /* some guess */
        loops_per_msec = (unsigned long long)lpj / 1000 * HZ;
@@ -218,10 +219,9 @@ static int __init boot_delay_setup(char *str)
        if (boot_delay > 10 * 1000)
                boot_delay = 0;
 
-       printk_delay_msec = loops_per_msec;
-       printk(KERN_DEBUG "boot_delay: %u, preset_lpj: %ld, lpj: %lu, "
-               "HZ: %d, printk_delay_msec: %llu\n",
-               boot_delay, preset_lpj, lpj, HZ, printk_delay_msec);
+       pr_debug("boot_delay: %u, preset_lpj: %ld, lpj: %lu, "
+               "HZ: %d, loops_per_msec: %llu\n",
+               boot_delay, preset_lpj, lpj, HZ, loops_per_msec);
        return 1;
 }
 __setup("boot_delay=", boot_delay_setup);
@@ -234,7 +234,7 @@ static void boot_delay_msec(void)
        if (boot_delay == 0 || system_state != SYSTEM_BOOTING)
                return;
 
-       k = (unsigned long long)printk_delay_msec * boot_delay;
+       k = (unsigned long long)loops_per_msec * boot_delay;
 
        timeout = jiffies + msecs_to_jiffies(boot_delay);
        while (k) {
@@ -378,10 +378,15 @@ int do_syslog(int type, char __user *buf, int len)
                logged_chars = 0;
                break;
        case 6:         /* Disable logging to console */
+               if (saved_console_loglevel == -1)
+                       saved_console_loglevel = console_loglevel;
                console_loglevel = minimum_console_loglevel;
                break;
        case 7:         /* Enable logging to console */
-               console_loglevel = default_console_loglevel;
+               if (saved_console_loglevel != -1) {
+                       console_loglevel = saved_console_loglevel;
+                       saved_console_loglevel = -1;
+               }
                break;
        case 8:         /* Set level of messages printed to console */
                error = -EINVAL;
@@ -390,6 +395,8 @@ int do_syslog(int type, char __user *buf, int len)
                if (len < minimum_console_loglevel)
                        len = minimum_console_loglevel;
                console_loglevel = len;
+               /* Implicitly re-enable logging to console */
+               saved_console_loglevel = -1;
                error = 0;
                break;
        case 9:         /* Number of chars in the log buffer */
@@ -646,6 +653,20 @@ static int recursion_bug;
 static int new_text_line = 1;
 static char printk_buf[1024];
 
+int printk_delay_msec __read_mostly;
+
+static inline void printk_delay(void)
+{
+       if (unlikely(printk_delay_msec)) {
+               int m = printk_delay_msec;
+
+               while (m--) {
+                       mdelay(1);
+                       touch_nmi_watchdog();
+               }
+       }
+}
+
 asmlinkage int vprintk(const char *fmt, va_list args)
 {
        int printed_len = 0;
@@ -655,6 +676,7 @@ asmlinkage int vprintk(const char *fmt, va_list args)
        char *p;
 
        boot_delay_msec();
+       printk_delay();
 
        preempt_disable();
        /* This stops the holder of console_sem just where we want him */
@@ -1066,12 +1088,6 @@ void __sched console_conditional_schedule(void)
 }
 EXPORT_SYMBOL(console_conditional_schedule);
 
-void console_print(const char *s)
-{
-       printk(KERN_EMERG "%s", s);
-}
-EXPORT_SYMBOL(console_print);
-
 void console_unblank(void)
 {
        struct console *c;
@@ -1343,7 +1359,7 @@ static int __init disable_boot_consoles(void)
                if (con->flags & CON_BOOT) {
                        printk(KERN_INFO "turn off boot console %s%d\n",
                                con->name, con->index);
-                       return unregister_console(con);
+                       unregister_console(con);
                }
        }
        return 0;