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author | Peter Zijlstra <peterz@infradead.org> | 2022-06-08 16:27:27 +0200 |
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committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2022-06-08 18:05:45 +0200 |
commit | 32d4fd5751eadbe1823a37eb38df85ec5c8e6207 (patch) | |
tree | a4b391660c689711f1523c8a8818f03fbdb18eb0 /drivers | |
parent | f2906aa863381afb0015a9eb7fefad885d4e5a56 (diff) | |
download | lwn-32d4fd5751eadbe1823a37eb38df85ec5c8e6207.tar.gz lwn-32d4fd5751eadbe1823a37eb38df85ec5c8e6207.zip |
cpuidle,intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE
Commit c227233ad64c ("intel_idle: enable interrupts before C1 on
Xeons") wrecked intel_idle in two ways:
- must not have tracing in idle functions
- must return with IRQs disabled
Additionally, it added a branch for no good reason.
Fixes: c227233ad64c ("intel_idle: enable interrupts before C1 on Xeons")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
[ rjw: Moved the intel_idle() kerneldoc comment next to the function ]
Cc: 5.16+ <stable@vger.kernel.org> # 5.16+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/idle/intel_idle.c | 32 |
1 files changed, 25 insertions, 7 deletions
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index b9bb94bd0f67..424ef470223d 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -115,6 +115,18 @@ static unsigned int mwait_substates __initdata; #define flg2MWAIT(flags) (((flags) >> 24) & 0xFF) #define MWAIT2flg(eax) ((eax & 0xFF) << 24) +static __always_inline int __intel_idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + struct cpuidle_state *state = &drv->states[index]; + unsigned long eax = flg2MWAIT(state->flags); + unsigned long ecx = 1; /* break on interrupt flag */ + + mwait_idle_with_hints(eax, ecx); + + return index; +} + /** * intel_idle - Ask the processor to enter the given idle state. * @dev: cpuidle device of the target CPU. @@ -132,16 +144,19 @@ static unsigned int mwait_substates __initdata; static __cpuidle int intel_idle(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index) { - struct cpuidle_state *state = &drv->states[index]; - unsigned long eax = flg2MWAIT(state->flags); - unsigned long ecx = 1; /* break on interrupt flag */ + return __intel_idle(dev, drv, index); +} - if (state->flags & CPUIDLE_FLAG_IRQ_ENABLE) - local_irq_enable(); +static __cpuidle int intel_idle_irq(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + int ret; - mwait_idle_with_hints(eax, ecx); + raw_local_irq_enable(); + ret = __intel_idle(dev, drv, index); + raw_local_irq_disable(); - return index; + return ret; } /** @@ -1801,6 +1816,9 @@ static void __init intel_idle_init_cstates_icpu(struct cpuidle_driver *drv) /* Structure copy. */ drv->states[drv->state_count] = cpuidle_state_table[cstate]; + if (cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_IRQ_ENABLE) + drv->states[drv->state_count].enter = intel_idle_irq; + if ((disabled_states_mask & BIT(drv->state_count)) || ((icpu->use_acpi || force_use_acpi) && intel_idle_off_by_default(mwait_hint) && |