softlockup: remove timestamp checking from hung_task

Impact: saves sizeof(long) bytes per task_struct

By guaranteeing that sysctl_hung_task_timeout_secs have elapsed between
tasklist scans we can avoid using timestamps.

Signed-off-by: Mandeep Singh Baines <msb@google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Mandeep Singh Baines
2009-02-06 15:37:47 -08:00
committed by Ingo Molnar
parent 94be52dc07
commit 17406b82d6
3 changed files with 12 additions and 45 deletions

View File

@@ -639,6 +639,9 @@ static int copy_mm(unsigned long clone_flags, struct task_struct * tsk)
tsk->min_flt = tsk->maj_flt = 0;
tsk->nvcsw = tsk->nivcsw = 0;
#ifdef CONFIG_DETECT_HUNG_TASK
tsk->last_switch_count = tsk->nvcsw + tsk->nivcsw;
#endif
tsk->mm = NULL;
tsk->active_mm = NULL;
@@ -1041,11 +1044,6 @@ static struct task_struct *copy_process(unsigned long clone_flags,
p->default_timer_slack_ns = current->timer_slack_ns;
#ifdef CONFIG_DETECT_HUNG_TASK
p->last_switch_count = 0;
p->last_switch_timestamp = 0;
#endif
task_io_accounting_init(&p->ioac);
acct_clear_integrals(p);