| Message ID | 20230322213949.23088-2-michael.reed@canonical.com |
|---|---|
| State | New |
| Headers | show |
| Series | Performance per Watt (DAPC) enabled in the BIOS | expand |
On 22.03.23 22:39, Michael Reed wrote: > From: Stuart Hayes <stuart.w.hayes@gmail.com> > > When acpi-cpufreq is loaded, boost is enabled on every CPU (by setting an > MSR) before the driver is registered with cpufreq. This can be very time > consuming, because it is done with a CPU hotplug startup callback, and > cpuhp_setup_state() schedules the callback (cpufreq_boost_online()) to run > on each CPU one at a time, waiting for each to run before calling the next. > > If cpufreq_register_driver() fails--if, for example, there are no ACPI > P-states present--this is wasted time. > > Since cpufreq already sets up a CPU hotplug startup callback if and when > acpi-cpufreq is registered, set the boost MSRs in acpi_cpufreq_cpu_init(), > which is called by the cpufreq cpuhp callback. This allows acpi-cpufreq to > exit quickly if it is loaded but not needed. > > On one system with 192 CPUs, this patch speeds up boot by about 30 seconds. > > BugLink: https://bugs.launchpad.net/bugs/2008527 > > Signed-off-by: Stuart Hayes <stuart.w.hayes@gmail.com> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > (cherry picked from commit 13fdbc8b8da6a2325cad3359c9a70504b0ff2f93) > Signed-off-by: Michael Reed <Michael.Reed@canonical.com> > --- Rejected for the following reasons: This is a patch from 6.2. While this might be ok for Lunar once it moves to that version, I can see no reason why this should not also apply and get applied to Kinetic. Even more so since desktop users that installed a fresh 22.04 will be on the HWE stream which is now a Kinetic kernel. -Stefan > drivers/cpufreq/acpi-cpufreq.c | 31 +++---------------------------- > 1 file changed, 3 insertions(+), 28 deletions(-) > > diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c > index 28467d83c745..8b5c84c9dc1e 100644 > --- a/drivers/cpufreq/acpi-cpufreq.c > +++ b/drivers/cpufreq/acpi-cpufreq.c > @@ -530,15 +530,6 @@ static void free_acpi_perf_data(void) > free_percpu(acpi_perf_data); > } > > -static int cpufreq_boost_online(unsigned int cpu) > -{ > - /* > - * On the CPU_UP path we simply keep the boost-disable flag > - * in sync with the current global state. > - */ > - return boost_set_msr(acpi_cpufreq_driver.boost_enabled); > -} > - > static int cpufreq_boost_down_prep(unsigned int cpu) > { > /* > @@ -892,6 +883,8 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy) > if (perf->states[0].core_frequency * 1000 != freq_table[0].frequency) > pr_warn(FW_WARN "P-state 0 is not max freq\n"); > > + set_boost(policy, acpi_cpufreq_driver.boost_enabled); > + > return result; > > err_unreg: > @@ -911,6 +904,7 @@ static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy) > > pr_debug("%s\n", __func__); > > + cpufreq_boost_down_prep(policy->cpu); > policy->fast_switch_possible = false; > policy->driver_data = NULL; > acpi_processor_unregister_performance(data->acpi_perf_cpu); > @@ -967,25 +961,9 @@ static void __init acpi_cpufreq_boost_init(void) > acpi_cpufreq_driver.set_boost = set_boost; > acpi_cpufreq_driver.boost_enabled = boost_state(0); > > - /* > - * This calls the online callback on all online cpu and forces all > - * MSRs to the same value. > - */ > - ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "cpufreq/acpi:online", > - cpufreq_boost_online, cpufreq_boost_down_prep); > - if (ret < 0) { > - pr_err("acpi_cpufreq: failed to register hotplug callbacks\n"); > - return; > - } > acpi_cpufreq_online = ret; > } > > -static void acpi_cpufreq_boost_exit(void) > -{ > - if (acpi_cpufreq_online > 0) > - cpuhp_remove_state_nocalls(acpi_cpufreq_online); > -} > - > static int __init acpi_cpufreq_init(void) > { > int ret; > @@ -1027,7 +1005,6 @@ static int __init acpi_cpufreq_init(void) > ret = cpufreq_register_driver(&acpi_cpufreq_driver); > if (ret) { > free_acpi_perf_data(); > - acpi_cpufreq_boost_exit(); > } > return ret; > } > @@ -1036,8 +1013,6 @@ static void __exit acpi_cpufreq_exit(void) > { > pr_debug("%s\n", __func__); > > - acpi_cpufreq_boost_exit(); > - > cpufreq_unregister_driver(&acpi_cpufreq_driver); > > free_acpi_perf_data();
diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c index 28467d83c745..8b5c84c9dc1e 100644 --- a/drivers/cpufreq/acpi-cpufreq.c +++ b/drivers/cpufreq/acpi-cpufreq.c @@ -530,15 +530,6 @@ static void free_acpi_perf_data(void) free_percpu(acpi_perf_data); } -static int cpufreq_boost_online(unsigned int cpu) -{ - /* - * On the CPU_UP path we simply keep the boost-disable flag - * in sync with the current global state. - */ - return boost_set_msr(acpi_cpufreq_driver.boost_enabled); -} - static int cpufreq_boost_down_prep(unsigned int cpu) { /* @@ -892,6 +883,8 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy) if (perf->states[0].core_frequency * 1000 != freq_table[0].frequency) pr_warn(FW_WARN "P-state 0 is not max freq\n"); + set_boost(policy, acpi_cpufreq_driver.boost_enabled); + return result; err_unreg: @@ -911,6 +904,7 @@ static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy) pr_debug("%s\n", __func__); + cpufreq_boost_down_prep(policy->cpu); policy->fast_switch_possible = false; policy->driver_data = NULL; acpi_processor_unregister_performance(data->acpi_perf_cpu); @@ -967,25 +961,9 @@ static void __init acpi_cpufreq_boost_init(void) acpi_cpufreq_driver.set_boost = set_boost; acpi_cpufreq_driver.boost_enabled = boost_state(0); - /* - * This calls the online callback on all online cpu and forces all - * MSRs to the same value. - */ - ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "cpufreq/acpi:online", - cpufreq_boost_online, cpufreq_boost_down_prep); - if (ret < 0) { - pr_err("acpi_cpufreq: failed to register hotplug callbacks\n"); - return; - } acpi_cpufreq_online = ret; } -static void acpi_cpufreq_boost_exit(void) -{ - if (acpi_cpufreq_online > 0) - cpuhp_remove_state_nocalls(acpi_cpufreq_online); -} - static int __init acpi_cpufreq_init(void) { int ret; @@ -1027,7 +1005,6 @@ static int __init acpi_cpufreq_init(void) ret = cpufreq_register_driver(&acpi_cpufreq_driver); if (ret) { free_acpi_perf_data(); - acpi_cpufreq_boost_exit(); } return ret; } @@ -1036,8 +1013,6 @@ static void __exit acpi_cpufreq_exit(void) { pr_debug("%s\n", __func__); - acpi_cpufreq_boost_exit(); - cpufreq_unregister_driver(&acpi_cpufreq_driver); free_acpi_perf_data();