From: Peter Zijlstra peterz@infradead.org
commit c3d42418dca53d6c498a48c408f7a45289593650 upstream.
Doing RCU-idle outside the driver, only to then temporarily enable it again, some *four* times, before going idle is suboptimal.
Notably three times explicitly using RCU_NONIDLE() and once implicitly through cpu_pm_*().
Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Signed-off-by: Ingo Molnar mingo@kernel.org Tested-by: Tony Lindgren tony@atomide.com Tested-by: Ulf Hansson ulf.hansson@linaro.org Reviewed-by: Frederic Weisbecker frederic@kernel.org Reviewed-by: Tony Lindgren tony@atomide.com Acked-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Link: https://lore.kernel.org/r/20230112195540.007918454@infradead.org Signed-off-by: Suren Baghdasaryan surenb@google.com Signed-off-by: Cheng-Jui Wang cheng-jui.wang@mediatek.com --- arch/arm/mach-omap2/cpuidle44xx.c | 29 ++++++++++++++++++----------- 1 file changed, 18 insertions(+), 11 deletions(-)
diff --git a/arch/arm/mach-omap2/cpuidle44xx.c b/arch/arm/mach-omap2/cpuidle44xx.c index de37027ad758..953ad888737c 100644 --- a/arch/arm/mach-omap2/cpuidle44xx.c +++ b/arch/arm/mach-omap2/cpuidle44xx.c @@ -105,7 +105,9 @@ static int omap_enter_idle_smp(struct cpuidle_device *dev, } raw_spin_unlock_irqrestore(&mpu_lock, flag);
+ ct_idle_enter(); omap4_enter_lowpower(dev->cpu, cx->cpu_state); + ct_idle_exit();
raw_spin_lock_irqsave(&mpu_lock, flag); if (cx->mpu_state_vote == num_online_cpus()) @@ -151,10 +153,10 @@ static int omap_enter_idle_coupled(struct cpuidle_device *dev, (cx->mpu_logic_state == PWRDM_POWER_OFF);
/* Enter broadcast mode for periodic timers */ - RCU_NONIDLE(tick_broadcast_enable()); + tick_broadcast_enable();
/* Enter broadcast mode for one-shot timers */ - RCU_NONIDLE(tick_broadcast_enter()); + tick_broadcast_enter();
/* * Call idle CPU PM enter notifier chain so that @@ -166,7 +168,7 @@ static int omap_enter_idle_coupled(struct cpuidle_device *dev,
if (dev->cpu == 0) { pwrdm_set_logic_retst(mpu_pd, cx->mpu_logic_state); - RCU_NONIDLE(omap_set_pwrdm_state(mpu_pd, cx->mpu_state)); + omap_set_pwrdm_state(mpu_pd, cx->mpu_state);
/* * Call idle CPU cluster PM enter notifier chain @@ -178,14 +180,16 @@ static int omap_enter_idle_coupled(struct cpuidle_device *dev, index = 0; cx = state_ptr + index; pwrdm_set_logic_retst(mpu_pd, cx->mpu_logic_state); - RCU_NONIDLE(omap_set_pwrdm_state(mpu_pd, cx->mpu_state)); + omap_set_pwrdm_state(mpu_pd, cx->mpu_state); mpuss_can_lose_context = 0; } } }
+ ct_idle_enter(); omap4_enter_lowpower(dev->cpu, cx->cpu_state); cpu_done[dev->cpu] = true; + ct_idle_exit();
/* Wakeup CPU1 only if it is not offlined */ if (dev->cpu == 0 && cpumask_test_cpu(1, cpu_online_mask)) { @@ -194,9 +198,9 @@ static int omap_enter_idle_coupled(struct cpuidle_device *dev, mpuss_can_lose_context) gic_dist_disable();
- RCU_NONIDLE(clkdm_deny_idle(cpu_clkdm[1])); - RCU_NONIDLE(omap_set_pwrdm_state(cpu_pd[1], PWRDM_POWER_ON)); - RCU_NONIDLE(clkdm_allow_idle(cpu_clkdm[1])); + clkdm_deny_idle(cpu_clkdm[1]); + omap_set_pwrdm_state(cpu_pd[1], PWRDM_POWER_ON); + clkdm_allow_idle(cpu_clkdm[1]);
if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD) && mpuss_can_lose_context) { @@ -222,7 +226,7 @@ static int omap_enter_idle_coupled(struct cpuidle_device *dev, cpu_pm_exit();
cpu_pm_out: - RCU_NONIDLE(tick_broadcast_exit()); + tick_broadcast_exit();
fail: cpuidle_coupled_parallel_barrier(dev, &abort_barrier); @@ -247,7 +251,8 @@ static struct cpuidle_driver omap4_idle_driver = { /* C2 - CPU0 OFF + CPU1 OFF + MPU CSWR */ .exit_latency = 328 + 440, .target_residency = 960, - .flags = CPUIDLE_FLAG_COUPLED, + .flags = CPUIDLE_FLAG_COUPLED | + CPUIDLE_FLAG_RCU_IDLE, .enter = omap_enter_idle_coupled, .name = "C2", .desc = "CPUx OFF, MPUSS CSWR", @@ -256,7 +261,8 @@ static struct cpuidle_driver omap4_idle_driver = { /* C3 - CPU0 OFF + CPU1 OFF + MPU OSWR */ .exit_latency = 460 + 518, .target_residency = 1100, - .flags = CPUIDLE_FLAG_COUPLED, + .flags = CPUIDLE_FLAG_COUPLED | + CPUIDLE_FLAG_RCU_IDLE, .enter = omap_enter_idle_coupled, .name = "C3", .desc = "CPUx OFF, MPUSS OSWR", @@ -282,7 +288,8 @@ static struct cpuidle_driver omap5_idle_driver = { /* C2 - CPU0 RET + CPU1 RET + MPU CSWR */ .exit_latency = 48 + 60, .target_residency = 100, - .flags = CPUIDLE_FLAG_TIMER_STOP, + .flags = CPUIDLE_FLAG_TIMER_STOP | + CPUIDLE_FLAG_RCU_IDLE, .enter = omap_enter_idle_smp, .name = "C2", .desc = "CPUx CSWR, MPUSS CSWR",