[PATCH] add ignore_loglevel boot option

[sfrench/cifs-2.6.git] / kernel / printk.c

diff --git a/kernel/printk.c b/kernel/printk.c
index 1149365e989edee40639bda0cd6865204e05cc89..185bb45eacf7289db6b99039634ad9f9f6fa5d96 100644 (file)
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -31,6 +31,7 @@
 #include <linux/security.h>
 #include <linux/bootmem.h>
 #include <linux/syscalls.h>
+#include <linux/jiffies.h>
 
 #include <asm/uaccess.h>
 
@@ -52,8 +53,6 @@ int console_printk[4] = {
        DEFAULT_CONSOLE_LOGLEVEL,       /* default_console_loglevel */
 };
 
-EXPORT_UNUSED_SYMBOL(console_printk);  /*  June 2006  */
-
 /*
  * Low lever drivers may need that to know if they can schedule in
  * their unblank() callback or not. So let's export it.
@@ -334,13 +333,25 @@ static void __call_console_drivers(unsigned long start, unsigned long end)
        }
 }
 
+static int __read_mostly ignore_loglevel;
+
+int __init ignore_loglevel_setup(char *str)
+{
+       ignore_loglevel = 1;
+       printk(KERN_INFO "debug: ignoring loglevel setting.\n");
+
+       return 1;
+}
+
+__setup("ignore_loglevel", ignore_loglevel_setup);
+
 /*
  * Write out chars from start to end - 1 inclusive
  */
 static void _call_console_drivers(unsigned long start,
                                unsigned long end, int msg_log_level)
 {
-       if (msg_log_level < console_loglevel &&
+       if ((msg_log_level < console_loglevel || ignore_loglevel) &&
                        console_drivers && start != end) {
                if ((start & LOG_BUF_MASK) > (end & LOG_BUF_MASK)) {
                        /* wrapped write */
@@ -630,12 +641,7 @@ EXPORT_SYMBOL(vprintk);
 
 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;
+       return -ENOSYS;
 }
 
 static void call_console_drivers(unsigned long start, unsigned long end)
@@ -721,6 +727,7 @@ int __init add_preferred_console(char *name, int idx, char *options)
        return 0;
 }
 
+#ifndef CONFIG_DISABLE_CONSOLE_SUSPEND
 /**
  * suspend_console - suspend the console subsystem
  *
@@ -728,6 +735,7 @@ int __init add_preferred_console(char *name, int idx, char *options)
  */
 void suspend_console(void)
 {
+       printk("Suspending console(s)\n");
        acquire_console_sem();
        console_suspended = 1;
 }
@@ -737,6 +745,7 @@ void resume_console(void)
        console_suspended = 0;
        release_console_sem();
 }
+#endif /* CONFIG_DISABLE_CONSOLE_SUSPEND */
 
 /**
  * acquire_console_sem - lock the console system for exclusive use.
@@ -773,7 +782,6 @@ int is_console_locked(void)
 {
        return console_locked;
 }
-EXPORT_UNUSED_SYMBOL(is_console_locked);  /*  June 2006  */
 
 /**
  * release_console_sem - unlock the console system
@@ -817,15 +825,8 @@ void release_console_sem(void)
        console_locked = 0;
        up(&console_sem);
        spin_unlock_irqrestore(&logbuf_lock, flags);
-       if (wake_klogd && !oops_in_progress && waitqueue_active(&log_wait)) {
-               /*
-                * If we printk from within the lock dependency code,
-                * from within the scheduler code, then do not lock
-                * up due to self-recursion:
-                */
-               if (!lockdep_internal())
-                       wake_up_interruptible(&log_wait);
-       }
+       if (wake_klogd && !oops_in_progress && waitqueue_active(&log_wait))
+               wake_up_interruptible(&log_wait);
 }
 EXPORT_SYMBOL(release_console_sem);
 
@@ -1105,3 +1106,23 @@ int printk_ratelimit(void)
                                printk_ratelimit_burst);
 }
 EXPORT_SYMBOL(printk_ratelimit);
+
+/**
+ * printk_timed_ratelimit - caller-controlled printk ratelimiting
+ * @caller_jiffies: pointer to caller's state
+ * @interval_msecs: minimum interval between prints
+ *
+ * printk_timed_ratelimit() returns true if more than @interval_msecs
+ * milliseconds have elapsed since the last time printk_timed_ratelimit()
+ * returned true.
+ */
+bool printk_timed_ratelimit(unsigned long *caller_jiffies,
+                       unsigned int interval_msecs)
+{
+       if (*caller_jiffies == 0 || time_after(jiffies, *caller_jiffies)) {
+               *caller_jiffies = jiffies + msecs_to_jiffies(interval_msecs);
+               return true;
+       }
+       return false;
+}
+EXPORT_SYMBOL(printk_timed_ratelimit);