lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

uml: eliminate interrupts in the idle loop

Browse Source 
Now, the idle loop now longer needs SIGALRM firing - it can just sleep for the
requisite amount of time and fake a timer interrupt when it finishes.

Any use of ITIMER_REAL now goes away.  disable_timer only turns off
ITIMER_VIRTUAL.  switch_timers is no longer needed, so it, and all calls, goes
away.

disable_timer now returns the amount of time remaining on the timer.
default_idle uses this to tell idle_sleep how long to sleep.  idle_sleep will
call alarm_handler if nanosleep returns 0, which is the case if it didn't
return early due to an interrupt.  Otherwise, it just returns.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Jeff Dike
2007-10-16 01:27:26 -07:00
committed by Linus Torvalds
parent d2753a6d19
commit b160fb6309
4 changed files with 18 additions and 53 deletions
Download Patch File Download Diff File Expand all files Collapse all files

7
arch/um/kernel/process.c
View File

@@ -235,6 +235,8 @@ void initial_thread_cb(void (*proc)(void *), void *arg)
void default_idle(void)
{
unsigned long long nsecs;
while(1) {
/* endless idle loop with no priority at all */
@@ -246,9 +248,8 @@ void default_idle(void)
schedule();
tick_nohz_stop_sched_tick();
switch_timers(1);
idle_sleep(10);
switch_timers(0);
nsecs = disable_timer();
idle_sleep(nsecs);
tick_nohz_restart_sched_tick();
}
}