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intel_idle: simplify test for leave_mm() 

A run-time test to invoke leave_mm() for the deepest
supported C-state is redundant, since the appropriate
C-states already have flags with CPUIDLE_FLAG_TLB_FLUSHED set.

Signed-off-by: Len Brown <len.brown@intel.com>
This commit is contained in:
Len Brown 2010-10-15 20:43:06 -04:00
parent cd07202cc8
commit c8381cc3d8
1 changed files with 3 additions and 6 deletions
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9
drivers/idle/intel_idle.c
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@ -186,13 +186,10 @@ static int intel_idle(struct cpuidle_device *dev, struct cpuidle_state *state)
local_irq_disable();
/*
* If the state flag indicates that the TLB will be flushed or if this
* is the deepest c-state supported, do a voluntary leave mm to avoid
* costly and mostly unnecessary wakeups for flushing the user TLB's
* associated with the active mm.
* leave_mm() to avoid costly and often unnecessary wakeups
* for flushing the user TLB's associated with the active mm.
*/
if (state->flags & CPUIDLE_FLAG_TLB_FLUSHED ||
(&dev->states[dev->state_count - 1] == state))
if (state->flags & CPUIDLE_FLAG_TLB_FLUSHED)
leave_mm(cpu);
if (!(lapic_timer_reliable_states & (1 << (cstate))))