From: Peter Zijlstra peterz@infradead.org
commit 0c5ffc3d7b15978c6b184938cd6b8af06e436424 upstream.
Doing RCU-idle outside the driver, only to then temporarily enable it again before going idle is suboptimal.
Notably: this converts all dt_init_idle_driver() and __CPU_PM_CPU_IDLE_ENTER() users for they are inextrably intertwined.
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 Acked-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Acked-by: Frederic Weisbecker frederic@kernel.org Link: https://lore.kernel.org/r/20230112195540.068981667@infradead.org Signed-off-by: Suren Baghdasaryan surenb@google.com Signed-off-by: Cheng-Jui Wang cheng-jui.wang@mediatek.com --- drivers/acpi/processor_idle.c | 2 ++ drivers/cpuidle/cpuidle-big_little.c | 8 ++++++-- drivers/cpuidle/dt_idle_states.c | 2 +- include/linux/cpuidle.h | 2 ++ 4 files changed, 11 insertions(+), 3 deletions(-)
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index fc5b5b2c9e81..ae42d530d080 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -1221,6 +1221,8 @@ static int acpi_processor_setup_lpi_states(struct acpi_processor *pr) state->target_residency = lpi->min_residency; if (lpi->arch_flags) state->flags |= CPUIDLE_FLAG_TIMER_STOP; + if (i != 0 && lpi->entry_method == ACPI_CSTATE_FFH) + state->flags |= CPUIDLE_FLAG_RCU_IDLE; state->enter = acpi_idle_lpi_enter; drv->safe_state_index = i; } diff --git a/drivers/cpuidle/cpuidle-big_little.c b/drivers/cpuidle/cpuidle-big_little.c index abe51185f243..fffd4ed0c4d1 100644 --- a/drivers/cpuidle/cpuidle-big_little.c +++ b/drivers/cpuidle/cpuidle-big_little.c @@ -64,7 +64,8 @@ static struct cpuidle_driver bl_idle_little_driver = { .enter = bl_enter_powerdown, .exit_latency = 700, .target_residency = 2500, - .flags = CPUIDLE_FLAG_TIMER_STOP, + .flags = CPUIDLE_FLAG_TIMER_STOP | + CPUIDLE_FLAG_RCU_IDLE, .name = "C1", .desc = "ARM little-cluster power down", }, @@ -85,7 +86,8 @@ static struct cpuidle_driver bl_idle_big_driver = { .enter = bl_enter_powerdown, .exit_latency = 500, .target_residency = 2000, - .flags = CPUIDLE_FLAG_TIMER_STOP, + .flags = CPUIDLE_FLAG_TIMER_STOP | + CPUIDLE_FLAG_RCU_IDLE, .name = "C1", .desc = "ARM big-cluster power down", }, @@ -124,11 +126,13 @@ static int bl_enter_powerdown(struct cpuidle_device *dev, struct cpuidle_driver *drv, int idx) { cpu_pm_enter(); + ct_idle_enter();
cpu_suspend(0, bl_powerdown_finisher);
/* signals the MCPM core that CPU is out of low power state */ mcpm_cpu_powered_up(); + ct_idle_exit();
cpu_pm_exit();
diff --git a/drivers/cpuidle/dt_idle_states.c b/drivers/cpuidle/dt_idle_states.c index 448bc796b0b4..fcfa7490eecf 100644 --- a/drivers/cpuidle/dt_idle_states.c +++ b/drivers/cpuidle/dt_idle_states.c @@ -77,7 +77,7 @@ static int init_state_node(struct cpuidle_state *idle_state, if (err) desc = state_node->name;
- idle_state->flags = 0; + idle_state->flags = CPUIDLE_FLAG_RCU_IDLE; if (of_property_read_bool(state_node, "local-timer-stop")) idle_state->flags |= CPUIDLE_FLAG_TIMER_STOP; /* diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h index fce476275e16..0ddc11e44302 100644 --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h @@ -289,7 +289,9 @@ extern s64 cpuidle_governor_latency_req(unsigned int cpu); if (!is_retention) \ __ret = cpu_pm_enter(); \ if (!__ret) { \ + ct_idle_enter(); \ __ret = low_level_idle_enter(state); \ + ct_idle_exit(); \ if (!is_retention) \ cpu_pm_exit(); \ } \