[PATCH v3 12/51] cpuidle,dt: Push RCU-idle into driver
From: Peter Zijlstra <peterz@infradead.org>
Date: 2023-01-12 20:04:17
Also in:
linux-acpi, linux-alpha, linux-arch, linux-arm-msm, linux-clk, linux-m68k, linux-mips, linux-mm, linux-omap, linux-perf-users, linux-pm, linux-riscv, linux-s390, linux-samsung-soc, linux-sh, linux-tegra, linux-um, linuxppc-dev, lkml, loongarch, sparclinux, virtualization
Doing RCU-idle outside the driver, only to then temporarily enable it again before going idle is daft. 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> Acked-by: Rafael J. Wysocki <redacted> Acked-by: Frederic Weisbecker <frederic@kernel.org> Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Ulf Hansson <redacted> --- drivers/acpi/processor_idle.c | 2 ++ drivers/cpuidle/cpuidle-arm.c | 1 + drivers/cpuidle/cpuidle-big_little.c | 8 ++++++-- drivers/cpuidle/cpuidle-psci.c | 1 + drivers/cpuidle/cpuidle-qcom-spm.c | 1 + drivers/cpuidle/cpuidle-riscv-sbi.c | 1 + drivers/cpuidle/dt_idle_states.c | 2 +- include/linux/cpuidle.h | 2 ++ 8 files changed, 15 insertions(+), 3 deletions(-)
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c@@ -1219,6 +1219,8 @@ static int acpi_processor_setup_lpi_stat 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; } --- a/drivers/cpuidle/cpuidle-big_little.c +++ b/drivers/cpuidle/cpuidle-big_little.c
@@ -64,7 +64,8 @@ static struct cpuidle_driver bl_idle_lit .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 .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 cpu 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(); --- a/drivers/cpuidle/dt_idle_states.c +++ b/drivers/cpuidle/dt_idle_states.c
@@ -77,7 +77,7 @@ static int init_state_node(struct cpuidl 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; /* --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h
@@ -289,7 +289,9 @@ extern s64 cpuidle_governor_latency_req( 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(); \ } \