[PATCH 4/6] futex: Use current->time_slack_ns for rt tasks too

From: Darren Hart
Date: Thu Mar 12 2009 - 03:56:57 EST


RT tasks should set their timer slack to 0 on their own. This patch removes
the 'if (rt_task()) slack = 0;' block in futex_wait.

Build and boot tested on a 4 way Intel x86_64 workstation. Passes basic
pthread_mutex and PI tests out of ltp/testcases/realtime.

Signed-off-by: Darren Hart <dvhltc@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
---

kernel/futex.c | 7 ++-----
1 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/kernel/futex.c b/kernel/futex.c
index e149545..6579912 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -1253,16 +1253,13 @@ retry:
if (!abs_time)
schedule();
else {
- unsigned long slack;
- slack = current->timer_slack_ns;
- if (rt_task(current))
- slack = 0;
hrtimer_init_on_stack(&t.timer,
clockrt ? CLOCK_REALTIME :
CLOCK_MONOTONIC,
HRTIMER_MODE_ABS);
hrtimer_init_sleeper(&t, current);
- hrtimer_set_expires_range_ns(&t.timer, *abs_time, slack);
+ hrtimer_set_expires_range_ns(&t.timer, *abs_time,
+ current->timer_slack_ns);

hrtimer_start_expires(&t.timer, HRTIMER_MODE_ABS);
if (!hrtimer_active(&t.timer))

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/