Re: [PATCH 6/6] cpuidle: Fix poll_idle() noinstr annotation
flat view
From: "Rafael J. Wysocki" <rafael@kernel.org>
Date: 2023-01-24 14:25:16
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kvm, linux-pm, lkml, virtualization
On Mon, Jan 23, 2023 at 9:58 PM Peter Zijlstra [off-list ref] wrote:
The instrumentation_begin()/end() annotations in poll_idle() were
complete nonsense. Specifically they caused tracing to happen in the
middle of noinstr code, resulting in RCU splats.
Now that local_clock() is noinstr, mark up the rest and let it rip.
Fixes: 00717eb8c955 ("cpuidle: Annotate poll_idle()")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reported-by: kernel test robot <redacted>
Link: https://lore.kernel.org/oe-lkp/202301192148.58ece903-oliver.sang@intel.com (local)Acked-by: Rafael J. Wysocki <redacted>
quoted hunk ↗ jump to hunk
--- drivers/cpuidle/cpuidle.c | 2 +- drivers/cpuidle/poll_state.c | 2 -- 2 files changed, 1 insertion(+), 3 deletions(-)--- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c@@ -426,7 +426,7 @@ void cpuidle_reflect(struct cpuidle_devi * @dev: the cpuidle device * */ -u64 cpuidle_poll_time(struct cpuidle_driver *drv, +__cpuidle u64 cpuidle_poll_time(struct cpuidle_driver *drv, struct cpuidle_device *dev) { int i; --- a/drivers/cpuidle/poll_state.c +++ b/drivers/cpuidle/poll_state.c@@ -15,7 +15,6 @@ static int __cpuidle poll_idle(struct cp { u64 time_start; - instrumentation_begin(); time_start = local_clock(); dev->poll_time_limit = false;@@ -42,7 +41,6 @@ static int __cpuidle poll_idle(struct cp raw_local_irq_disable(); current_clr_polling(); - instrumentation_end(); return index; }