[PATCH 13/36] cpuidle,dt: Push RCU-idle into driver
From: Peter Zijlstra <peterz@infradead.org>
Date: 2022-06-08 14:47:59
Also in:
linux-acpi, linux-alpha, linux-arch, linux-arm-msm, linux-clk, linux-m68k, linux-mips, linux-omap, linux-perf-users, linux-pm, linux-riscv, linux-s390, linux-sh, linux-tegra, linux-um, lkml, rcu, sparclinux, virtualization, xen-devel
, Arnd Bergmann [off-list ref], ulli.kroll@googlemail.com, vgupta@kernel.org, linux-clk@vger.kernel.org, josh@joshtriplett.org, rostedt@goodmis.org, rcu@vger.kernel.org, bp@alien8.de, bcain@quicinc.com, tsbogend@alpha.franken.de, linux-parisc@vger.kernel.org, sudeep.holla@arm.com, shawnguo@kernel.org, davem@davemloft.net, dalias@libc.org, tony@atomide.com, amakhalov@vmware.com, bjorn.andersson@linaro.org, hpa@zytor.com, sparclinux@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-riscv@lists.infradead.org, anton.ivanov@cambridgegreys.com, jonas@southpole.se, yury.norov@gmail.com, richard@nod.at, x86@kernel.org, linux@armlinux.org.uk, mingo@redhat.com, aou@eecs.berkeley.edu, paulmck@kernel.org, hca@linux.ibm.com, stefan.kristiansson@saunalahti.fi, openrisc@lists.librecores.org, paul.walmsley@sifive.com, linux-tegra@vger.kernel.org, namhyung@kernel.org, andriy.shevchenko@linux.intel.com, jpoimboe@kernel.org, jgross@suse.com, monstr@monstr.eu, linux-mips@vger.kernel.org, palmer@dab belt.com, anup@brainfault.org, ink@jurassic.park.msu.ru, johannes@sipsolutions.net, linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" [off-list ref] 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> --- arch/arm/mach-omap2/cpuidle34xx.c | 4 ++-- 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 | 4 ++++ 9 files changed, 19 insertions(+), 5 deletions(-)
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c@@ -1200,6 +1200,8 @@ static int acpi_processor_setup_lpi_stat state->target_residency = lpi->min_residency; if (lpi->arch_flags) state->flags |= CPUIDLE_FLAG_TIMER_STOP; + if (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-arm.c +++ b/drivers/cpuidle/cpuidle-arm.c
@@ -53,6 +53,7 @@ static struct cpuidle_driver arm_idle_dr * handler for idle state index 0. */ .states[0] = { + .flags = CPUIDLE_FLAG_RCU_IDLE, .enter = arm_enter_idle_state, .exit_latency = 1, .target_residency = 1, --- 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(); + rcu_idle_enter(); cpu_suspend(0, bl_powerdown_finisher); /* signals the MCPM core that CPU is out of low power state */ mcpm_cpu_powered_up(); + rcu_idle_exit(); cpu_pm_exit(); --- a/drivers/cpuidle/cpuidle-psci.c +++ b/drivers/cpuidle/cpuidle-psci.c
@@ -357,6 +357,7 @@ static int psci_idle_init_cpu(struct dev * PSCI idle states relies on architectural WFI to be represented as * state index 0. */ + drv->states[0].flags = CPUIDLE_FLAG_RCU_IDLE; drv->states[0].enter = psci_enter_idle_state; drv->states[0].exit_latency = 1; drv->states[0].target_residency = 1; --- a/drivers/cpuidle/cpuidle-qcom-spm.c +++ b/drivers/cpuidle/cpuidle-qcom-spm.c
@@ -72,6 +72,7 @@ static struct cpuidle_driver qcom_spm_id .owner = THIS_MODULE, .states[0] = { .enter = spm_enter_idle_state, + .flags = CPUIDLE_FLAG_RCU_IDLE, .exit_latency = 1, .target_residency = 1, .power_usage = UINT_MAX, --- a/drivers/cpuidle/cpuidle-riscv-sbi.c +++ b/drivers/cpuidle/cpuidle-riscv-sbi.c
@@ -332,6 +332,7 @@ static int sbi_cpuidle_init_cpu(struct d drv->cpumask = (struct cpumask *)cpumask_of(cpu); /* RISC-V architectural WFI to be represented as state index 0. */ + drv->states[0].flags = CPUIDLE_FLAG_RCU_IDLE; drv->states[0].enter = sbi_cpuidle_enter_state; drv->states[0].exit_latency = 1; drv->states[0].target_residency = 1; --- 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
@@ -282,14 +282,18 @@ extern s64 cpuidle_governor_latency_req( int __ret = 0; \ \ if (!idx) { \ + rcu_idle_enter(); \ cpu_do_idle(); \ + rcu_idle_exit(); \ return idx; \ } \ \ if (!is_retention) \ __ret = cpu_pm_enter(); \ if (!__ret) { \ + rcu_idle_enter(); \ __ret = low_level_idle_enter(state); \ + rcu_idle_exit(); \ if (!is_retention) \ cpu_pm_exit(); \ } \