Eric Lee / linux-smarc-t335x-v3.2

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Commit 37bb6cb4097e29ffee970065b74499cbf10603a3

Authored by Peter Zijlstra
Committed by Ingo Molnar
1 parent d3d74453c3
Exists in master and in 4 other branches v3.2_AM335xPSP_04.06.00.11, v3.2_NEWT335xPSP_04.06.00.11, v3.2_SBC_SMARTMEN, v3.2_SMARCT335xPSP_04.06.00.11

hrtimer: unlock hrtimer_wakeup 

hrtimer_wakeup creates a

  base->lock
    rq->lock

lock dependancy. Avoid this by switching to HRTIMER_CB_IRQSAFE_NO_SOFTIRQ
which doesn't hold base->lock.

This fully untangles hrtimer locks from the scheduler locks, and allows
hrtimer usage in the scheduler proper.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Showing 1 changed file with 3 additions and 1 deletions Side-by-side Diff

... ... @@ -1293,7 +1293,7 @@
1293 1293 sl->timer.function = hrtimer_wakeup;
1294 1294 sl->task = task;
1295 1295 #ifdef CONFIG_HIGH_RES_TIMERS
1296   - sl->timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_RESTART;
  1296 + sl->timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ;
1297 1297 #endif
1298 1298 }
1299 1299  
... ... @@ -1304,6 +1304,8 @@
1304 1304 do {
1305 1305 set_current_state(TASK_INTERRUPTIBLE);
1306 1306 hrtimer_start(&t->timer, t->timer.expires, mode);
  1307 + if (!hrtimer_active(&t->timer))
  1308 + t->task = NULL;
1307 1309  
1308 1310 if (likely(t->task))
1309 1311 schedule();