add printk.time option, deprecate 'time'

Allow printk_time to be enabled or disabled at boot time.  Previously it
could be enabled only, but not disabled.

Change printk_time from an int to a bool since that's what it is.  Make its
logical (exposed) name just be "time" (was "printk_time").

Note: Changes kernel boot option syntax from "time" to "printk.time=value".

Since printk_time is declared as a module_param, it can also be
changed at run-time by modifying
  /sys/module/printk/parameters/time
to a value of 1/Y/y to enabled it or 0/N/n to disable it.

Since printk_time is declared as a module_param, its value can also
be set at boot-time by using
  linux printk.time=<bool>

If the "time" boot option is used, print a message that it is deprecated
and will be removed.

Note its planned removal in feature-removal-schedule.txt.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 1 deletions

diff --git a/kernel/printk.c b/kernel/printk.c
index f46cc6dff46..fccacf706f5 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -449,13 +449,16 @@ static int printk_time = 1;
 #else
 static int printk_time = 0;
 #endif
-module_param(printk_time, int, S_IRUGO | S_IWUSR);
+module_param_named(time, printk_time, bool, S_IRUGO | S_IWUSR);
 
 static int __init printk_time_setup(char *str)
 {
         if (*str)
                 return 0;
         printk_time = 1;
+        printk(KERN_NOTICE "The 'time' option is deprecated and "
+                "is scheduled for removal in early 2008\n");
+        printk(KERN_NOTICE "Use 'printk.time=<value>' instead\n");
         return 1;
 }