async: Handle kthread_run() return codes.

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

diff --git a/kernel/printk.c b/kernel/printk.c
index c3ab51d..69188f2 100644 (file)
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -233,45 +233,6 @@ static inline void boot_delay_msec(void)
 #endif
 
 /*
- * Return the number of unread characters in the log buffer.
- */
-static int log_buf_get_len(void)
-{
-       return logged_chars;
-}
-
-/*
- * Copy a range of characters from the log buffer.
- */
-int log_buf_copy(char *dest, int idx, int len)
-{
-       int ret, max;
-       bool took_lock = false;
-
-       if (!oops_in_progress) {
-               spin_lock_irq(&logbuf_lock);
-               took_lock = true;
-       }
-
-       max = log_buf_get_len();
-       if (idx < 0 || idx >= max) {
-               ret = -1;
-       } else {
-               if (len > max)
-                       len = max;
-               ret = len;
-               idx += (log_end - max);
-               while (len-- > 0)
-                       dest[len] = LOG_BUF(idx + len);
-       }
-
-       if (took_lock)
-               spin_unlock_irq(&logbuf_lock);
-
-       return ret;
-}
-
-/*
  * Commands to do_syslog:
  *
  *     0 -- Close the log.  Currently a NOP.
@@ -421,7 +382,7 @@ out:
        return error;
 }
 
-asmlinkage long sys_syslog(int type, char __user *buf, int len)
+SYSCALL_DEFINE3(syslog, int, type, char __user *, buf, int, len)
 {
        return do_syslog(type, buf, len);
 }
@@ -577,9 +538,6 @@ 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 +551,8 @@ 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, ...)
@@ -659,7 +619,7 @@ static int acquire_console_semaphore_for_printk(unsigned int cpu)
 static const char recursion_bug_msg [] =
                KERN_CRIT "BUG: recent printk recursion!\n";
 static int recursion_bug;
-       static int new_text_line = 1;
+static int new_text_line = 1;
 static char printk_buf[1024];
 
 asmlinkage int vprintk(const char *fmt, va_list args)
@@ -702,7 +662,7 @@ asmlinkage int vprintk(const char *fmt, va_list args)
        if (recursion_bug) {
                recursion_bug = 0;
                strcpy(printk_buf, recursion_bug_msg);
-               printed_len = sizeof(recursion_bug_msg);
+               printed_len = strlen(recursion_bug_msg);
        }
        /* Emit the output into the temporary buffer */
        printed_len += vscnprintf(printk_buf + printed_len,
@@ -782,11 +742,6 @@ EXPORT_SYMBOL(vprintk);
 
 #else
 
-asmlinkage long sys_syslog(int type, char __user *buf, int len)
-{
-       return -ENOSYS;
-}
-
 static void call_console_drivers(unsigned start, unsigned end)
 {
 }
@@ -982,10 +937,25 @@ 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;
 }
 
 /**