From 5ae4a4b45d4396aa7f7c008c4ae9eca981d43f8c Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Tue, 2 Feb 2021 10:25:11 +0530 Subject: [PATCH] cpufreq: Remove CPUFREQ_STICKY flag During cpufreq driver's registration, if the ->init() callback for all the CPUs fail then there is not much point in keeping the driver around as it will only account for more of unnecessary noise, for example cpufreq core will try to suspend/resume the driver which never got registered properly. The removal of such a driver is avoided if the driver carries the CPUFREQ_STICKY flag. This was added way back [1] in 2004 and perhaps no one should ever need it now. A lot of drivers do set this flag, probably because they just copied it from other drivers. This was added earlier for some platforms [2] because their cpufreq drivers were getting registered before the CPUs were registered with subsys framework. And hence they used to fail. The same isn't true anymore though. The current code flow in the kernel is: start_kernel() -> kernel_init() -> kernel_init_freeable() -> do_basic_setup() -> driver_init() -> cpu_dev_init() -> subsys_system_register() //For CPUs -> do_initcalls() -> cpufreq_register_driver() Clearly, the CPUs will always get registered with subsys framework before any cpufreq driver can get probed. Remove the flag and update the relevant drivers. Link: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit/include/linux/cpufreq.h?id=7cc9f0d9a1ab04cedc60d64fd8dcf7df224a3b4d # [1] Link: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit/arch/arm/mach-sa1100/cpu-sa1100.c?id=f59d3bbe35f6268d729f51be82af8325d62f20f5 # [2] Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/cpufreq-dt.c | 2 +- drivers/cpufreq/cpufreq.c | 3 +-- drivers/cpufreq/davinci-cpufreq.c | 2 +- drivers/cpufreq/loongson1-cpufreq.c | 2 +- drivers/cpufreq/mediatek-cpufreq.c | 2 +- drivers/cpufreq/omap-cpufreq.c | 2 +- drivers/cpufreq/qcom-cpufreq-hw.c | 2 +- drivers/cpufreq/s3c24xx-cpufreq.c | 2 +- drivers/cpufreq/s5pv210-cpufreq.c | 2 +- drivers/cpufreq/sa1100-cpufreq.c | 2 +- drivers/cpufreq/sa1110-cpufreq.c | 2 +- drivers/cpufreq/scmi-cpufreq.c | 2 +- drivers/cpufreq/scpi-cpufreq.c | 2 +- drivers/cpufreq/spear-cpufreq.c | 2 +- drivers/cpufreq/tegra186-cpufreq.c | 2 +- drivers/cpufreq/tegra194-cpufreq.c | 3 +-- drivers/cpufreq/vexpress-spc-cpufreq.c | 3 +-- include/linux/cpufreq.h | 17 +++++++---------- 18 files changed, 24 insertions(+), 30 deletions(-) diff --git a/drivers/cpufreq/cpufreq-dt.c b/drivers/cpufreq/cpufreq-dt.c index ad42345..b1e1bdc 100644 --- a/drivers/cpufreq/cpufreq-dt.c +++ b/drivers/cpufreq/cpufreq-dt.c @@ -175,7 +175,7 @@ static int cpufreq_exit(struct cpufreq_policy *policy) } static struct cpufreq_driver dt_cpufreq_driver = { - .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK | + .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK | CPUFREQ_IS_COOLING_DEV, .verify = cpufreq_generic_frequency_table_verify, .target_index = set_target, diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index d0a3525..7d0ae968 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -2810,8 +2810,7 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data) if (ret) goto err_boost_unreg; - if (!(cpufreq_driver->flags & CPUFREQ_STICKY) && - list_empty(&cpufreq_policy_list)) { + if (unlikely(list_empty(&cpufreq_policy_list))) { /* if all ->init() calls failed, unregister */ ret = -ENODEV; pr_debug("%s: No CPU initialized for driver %s\n", __func__, diff --git a/drivers/cpufreq/davinci-cpufreq.c b/drivers/cpufreq/davinci-cpufreq.c index 91f477a..9e97f60 100644 --- a/drivers/cpufreq/davinci-cpufreq.c +++ b/drivers/cpufreq/davinci-cpufreq.c @@ -95,7 +95,7 @@ static int davinci_cpu_init(struct cpufreq_policy *policy) } static struct cpufreq_driver davinci_driver = { - .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK, + .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK, .verify = cpufreq_generic_frequency_table_verify, .target_index = davinci_target, .get = cpufreq_generic_get, diff --git a/drivers/cpufreq/loongson1-cpufreq.c b/drivers/cpufreq/loongson1-cpufreq.c index 86f6125..fb72d70 100644 --- a/drivers/cpufreq/loongson1-cpufreq.c +++ b/drivers/cpufreq/loongson1-cpufreq.c @@ -116,7 +116,7 @@ static int ls1x_cpufreq_exit(struct cpufreq_policy *policy) static struct cpufreq_driver ls1x_cpufreq_driver = { .name = "cpufreq-ls1x", - .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK, + .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK, .verify = cpufreq_generic_frequency_table_verify, .target_index = ls1x_cpufreq_target, .get = cpufreq_generic_get, diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c index 022e3e9..f2e491b 100644 --- a/drivers/cpufreq/mediatek-cpufreq.c +++ b/drivers/cpufreq/mediatek-cpufreq.c @@ -463,7 +463,7 @@ static int mtk_cpufreq_exit(struct cpufreq_policy *policy) } static struct cpufreq_driver mtk_cpufreq_driver = { - .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK | + .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK | CPUFREQ_HAVE_GOVERNOR_PER_POLICY | CPUFREQ_IS_COOLING_DEV, .verify = cpufreq_generic_frequency_table_verify, diff --git a/drivers/cpufreq/omap-cpufreq.c b/drivers/cpufreq/omap-cpufreq.c index 3694bb0..e035ee2 100644 --- a/drivers/cpufreq/omap-cpufreq.c +++ b/drivers/cpufreq/omap-cpufreq.c @@ -144,7 +144,7 @@ static int omap_cpu_exit(struct cpufreq_policy *policy) } static struct cpufreq_driver omap_driver = { - .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK, + .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK, .verify = cpufreq_generic_frequency_table_verify, .target_index = omap_target, .get = cpufreq_generic_get, diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c b/drivers/cpufreq/qcom-cpufreq-hw.c index 9ed5341..2a3b4f4 100644 --- a/drivers/cpufreq/qcom-cpufreq-hw.c +++ b/drivers/cpufreq/qcom-cpufreq-hw.c @@ -374,7 +374,7 @@ static struct freq_attr *qcom_cpufreq_hw_attr[] = { }; static struct cpufreq_driver cpufreq_qcom_hw_driver = { - .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK | + .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK | CPUFREQ_HAVE_GOVERNOR_PER_POLICY | CPUFREQ_IS_COOLING_DEV, .verify = cpufreq_generic_frequency_table_verify, diff --git a/drivers/cpufreq/s3c24xx-cpufreq.c b/drivers/cpufreq/s3c24xx-cpufreq.c index 37efc0d..7380c32 100644 --- a/drivers/cpufreq/s3c24xx-cpufreq.c +++ b/drivers/cpufreq/s3c24xx-cpufreq.c @@ -420,7 +420,7 @@ static int s3c_cpufreq_resume(struct cpufreq_policy *policy) #endif static struct cpufreq_driver s3c24xx_driver = { - .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK, + .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK, .target = s3c_cpufreq_target, .get = cpufreq_generic_get, .init = s3c_cpufreq_init, diff --git a/drivers/cpufreq/s5pv210-cpufreq.c b/drivers/cpufreq/s5pv210-cpufreq.c index bed496c..69786e5 100644 --- a/drivers/cpufreq/s5pv210-cpufreq.c +++ b/drivers/cpufreq/s5pv210-cpufreq.c @@ -574,7 +574,7 @@ static int s5pv210_cpufreq_reboot_notifier_event(struct notifier_block *this, } static struct cpufreq_driver s5pv210_driver = { - .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK, + .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK, .verify = cpufreq_generic_frequency_table_verify, .target_index = s5pv210_target, .get = cpufreq_generic_get, diff --git a/drivers/cpufreq/sa1100-cpufreq.c b/drivers/cpufreq/sa1100-cpufreq.c index 5c075ef..252b9fc 100644 --- a/drivers/cpufreq/sa1100-cpufreq.c +++ b/drivers/cpufreq/sa1100-cpufreq.c @@ -186,7 +186,7 @@ static int __init sa1100_cpu_init(struct cpufreq_policy *policy) } static struct cpufreq_driver sa1100_driver __refdata = { - .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK | + .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK | CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING, .verify = cpufreq_generic_frequency_table_verify, .target_index = sa1100_target, diff --git a/drivers/cpufreq/sa1110-cpufreq.c b/drivers/cpufreq/sa1110-cpufreq.c index d9d04d9..1a83c86 100644 --- a/drivers/cpufreq/sa1110-cpufreq.c +++ b/drivers/cpufreq/sa1110-cpufreq.c @@ -310,7 +310,7 @@ static int __init sa1110_cpu_init(struct cpufreq_policy *policy) /* sa1110_driver needs __refdata because it must remain after init registers * it with cpufreq_register_driver() */ static struct cpufreq_driver sa1110_driver __refdata = { - .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK | + .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK | CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING, .verify = cpufreq_generic_frequency_table_verify, .target_index = sa1110_target, diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c index 491a0a2..5bd03b5 100644 --- a/drivers/cpufreq/scmi-cpufreq.c +++ b/drivers/cpufreq/scmi-cpufreq.c @@ -217,7 +217,7 @@ static int scmi_cpufreq_exit(struct cpufreq_policy *policy) static struct cpufreq_driver scmi_cpufreq_driver = { .name = "scmi", - .flags = CPUFREQ_STICKY | CPUFREQ_HAVE_GOVERNOR_PER_POLICY | + .flags = CPUFREQ_HAVE_GOVERNOR_PER_POLICY | CPUFREQ_NEED_INITIAL_FREQ_CHECK | CPUFREQ_IS_COOLING_DEV, .verify = cpufreq_generic_frequency_table_verify, diff --git a/drivers/cpufreq/scpi-cpufreq.c b/drivers/cpufreq/scpi-cpufreq.c index e5140ad..d6a698a 100644 --- a/drivers/cpufreq/scpi-cpufreq.c +++ b/drivers/cpufreq/scpi-cpufreq.c @@ -191,7 +191,7 @@ static int scpi_cpufreq_exit(struct cpufreq_policy *policy) static struct cpufreq_driver scpi_cpufreq_driver = { .name = "scpi-cpufreq", - .flags = CPUFREQ_STICKY | CPUFREQ_HAVE_GOVERNOR_PER_POLICY | + .flags = CPUFREQ_HAVE_GOVERNOR_PER_POLICY | CPUFREQ_NEED_INITIAL_FREQ_CHECK | CPUFREQ_IS_COOLING_DEV, .verify = cpufreq_generic_frequency_table_verify, diff --git a/drivers/cpufreq/spear-cpufreq.c b/drivers/cpufreq/spear-cpufreq.c index 73bd8dc..7d0d62a 100644 --- a/drivers/cpufreq/spear-cpufreq.c +++ b/drivers/cpufreq/spear-cpufreq.c @@ -160,7 +160,7 @@ static int spear_cpufreq_init(struct cpufreq_policy *policy) static struct cpufreq_driver spear_cpufreq_driver = { .name = "cpufreq-spear", - .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK, + .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK, .verify = cpufreq_generic_frequency_table_verify, .target_index = spear_cpufreq_target, .get = cpufreq_generic_get, diff --git a/drivers/cpufreq/tegra186-cpufreq.c b/drivers/cpufreq/tegra186-cpufreq.c index e566ea2..5d1943e 100644 --- a/drivers/cpufreq/tegra186-cpufreq.c +++ b/drivers/cpufreq/tegra186-cpufreq.c @@ -117,7 +117,7 @@ static unsigned int tegra186_cpufreq_get(unsigned int cpu) static struct cpufreq_driver tegra186_cpufreq_driver = { .name = "tegra186", - .flags = CPUFREQ_STICKY | CPUFREQ_HAVE_GOVERNOR_PER_POLICY | + .flags = CPUFREQ_HAVE_GOVERNOR_PER_POLICY | CPUFREQ_NEED_INITIAL_FREQ_CHECK, .get = tegra186_cpufreq_get, .verify = cpufreq_generic_frequency_table_verify, diff --git a/drivers/cpufreq/tegra194-cpufreq.c b/drivers/cpufreq/tegra194-cpufreq.c index 6a67f36..a9620e4 100644 --- a/drivers/cpufreq/tegra194-cpufreq.c +++ b/drivers/cpufreq/tegra194-cpufreq.c @@ -272,8 +272,7 @@ static int tegra194_cpufreq_set_target(struct cpufreq_policy *policy, static struct cpufreq_driver tegra194_cpufreq_driver = { .name = "tegra194", - .flags = CPUFREQ_STICKY | CPUFREQ_CONST_LOOPS | - CPUFREQ_NEED_INITIAL_FREQ_CHECK, + .flags = CPUFREQ_CONST_LOOPS | CPUFREQ_NEED_INITIAL_FREQ_CHECK, .verify = cpufreq_generic_frequency_table_verify, .target_index = tegra194_cpufreq_set_target, .get = tegra194_get_speed, diff --git a/drivers/cpufreq/vexpress-spc-cpufreq.c b/drivers/cpufreq/vexpress-spc-cpufreq.c index f711d8e..51dfa9a 100644 --- a/drivers/cpufreq/vexpress-spc-cpufreq.c +++ b/drivers/cpufreq/vexpress-spc-cpufreq.c @@ -486,8 +486,7 @@ static void ve_spc_cpufreq_ready(struct cpufreq_policy *policy) static struct cpufreq_driver ve_spc_cpufreq_driver = { .name = "vexpress-spc", - .flags = CPUFREQ_STICKY | - CPUFREQ_HAVE_GOVERNOR_PER_POLICY | + .flags = CPUFREQ_HAVE_GOVERNOR_PER_POLICY | CPUFREQ_NEED_INITIAL_FREQ_CHECK, .verify = cpufreq_generic_frequency_table_verify, .target_index = ve_spc_cpufreq_set_target, diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 9c8b743..c8e40e9 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -387,8 +387,13 @@ struct cpufreq_driver { /* flags */ -/* driver isn't removed even if all ->init() calls failed */ -#define CPUFREQ_STICKY BIT(0) +/* + * Set by drivers that need to update internale upper and lower boundaries along + * with the target frequency and so the core and governors should also invoke + * the diver if the target frequency does not change, but the policy min or max + * may have changed. + */ +#define CPUFREQ_NEED_UPDATE_LIMITS BIT(0) /* loops_per_jiffy or other kernel "constants" aren't affected by frequency transitions */ #define CPUFREQ_CONST_LOOPS BIT(1) @@ -432,14 +437,6 @@ struct cpufreq_driver { */ #define CPUFREQ_IS_COOLING_DEV BIT(7) -/* - * Set by drivers that need to update internale upper and lower boundaries along - * with the target frequency and so the core and governors should also invoke - * the diver if the target frequency does not change, but the policy min or max - * may have changed. - */ -#define CPUFREQ_NEED_UPDATE_LIMITS BIT(8) - int cpufreq_register_driver(struct cpufreq_driver *driver_data); int cpufreq_unregister_driver(struct cpufreq_driver *driver_data); -- 2.7.4