Merge git://git.kernel.org/pub/scm/linux/kernel/git/hskinnemoen/avr32-2.6

[linux-2.6-omap-h63xx.git] / kernel / printk.c

diff --git a/kernel/printk.c b/kernel/printk.c
index c3ab51dc9faf4cbf5118649e319a9697d3769aa7..6341af77eb65b559c1bf66e5cc7664b06779a694 100644 (file)
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -577,9 +577,6 @@ static int have_callable_console(void)
  * @fmt: format string
  *
  * This is printk().  It can be called from any context.  We want it to work.
- * Be aware of the fact that if oops_in_progress is not set, we might try to
- * wake klogd up which could deadlock on runqueue lock if printk() is called
- * from scheduler code.
  *
  * We try to grab the console_sem.  If we succeed, it's easy - we log the output and
  * call the console drivers.  If we fail to get the semaphore we place the output
@@ -593,6 +590,8 @@ static int have_callable_console(void)
  *
  * See also:
  * printf(3)
+ *
+ * See the vsnprintf() documentation for format string extensions over C99.
  */
 
 asmlinkage int printk(const char *fmt, ...)
@@ -982,10 +981,25 @@ int is_console_locked(void)
        return console_locked;
 }
 
-void wake_up_klogd(void)
+static DEFINE_PER_CPU(int, printk_pending);
+
+void printk_tick(void)
 {
-       if (!oops_in_progress && waitqueue_active(&log_wait))
+       if (__get_cpu_var(printk_pending)) {
+               __get_cpu_var(printk_pending) = 0;
                wake_up_interruptible(&log_wait);
+       }
+}
+
+int printk_needs_cpu(int cpu)
+{
+       return per_cpu(printk_pending, cpu);
+}
+
+void wake_up_klogd(void)
+{
+       if (waitqueue_active(&log_wait))
+               __raw_get_cpu_var(printk_pending) = 1;
 }
 
 /**