This commit moves CPU hotplug callbacks from ETMv4 driver to core layer. The motivation is the core layer can control all components on an activated path rather but not only managing tracer in ETMv4 driver.
The perf event layer will disable CoreSight PMU event 'cs_etm' when hotplug off a CPU. That means a perf mode will be always converted to disabled mode in CPU hotplug. Arm CoreSight CPU hotplug callbacks only need to handle the Sysfs mode and ignore the perf mode.
The core layer disables and releases the active path when hotplug-off a CPU. When hotplug-in a CPU, it does not re-enable the path, in this case, users need to re-enable the trace via Sysfs interface.
Tested-by: James Clark james.clark@linaro.org Signed-off-by: Leo Yan leo.yan@arm.com --- drivers/hwtracing/coresight/coresight-core.c | 42 +++++++++++++++++++++- drivers/hwtracing/coresight/coresight-etm3x-core.c | 40 --------------------- drivers/hwtracing/coresight/coresight-etm4x-core.c | 37 ------------------- 3 files changed, 41 insertions(+), 78 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c index ee97e4adbc395d4a4aa88846df91b0b53ae0bd8d..86beb9adefaa22007572b79c2e5d70cc4b731840 100644 --- a/drivers/hwtracing/coresight/coresight-core.c +++ b/drivers/hwtracing/coresight/coresight-core.c @@ -1706,6 +1706,33 @@ static void coresight_pm_restore(struct coresight_device *csdev) csdev->path->in_idle = false; }
+static int coresight_dying_cpu(unsigned int cpu) +{ + struct coresight_device *source = per_cpu(csdev_source, cpu); + struct coresight_path *path; + + if (!source || !source->path) + return 0; + + /* + * The perf event layer will disable PMU events in the CPU hotplug. + * CoreSight driver should never handle the CS_MODE_PERF case. + */ + if (coresight_get_mode(source) != CS_MODE_SYSFS) + return 0; + + /* + * Save 'source->path' here, as it will be cleared in + * coresight_disable_source(). + */ + path = source->path; + + coresight_disable_source(source, NULL); + coresight_disable_path(path); + coresight_release_path(path); + return 0; +} + static int coresight_cpu_pm_notify(struct notifier_block *nb, unsigned long cmd, void *v) { @@ -1737,11 +1764,24 @@ static struct notifier_block coresight_cpu_pm_nb = {
static int __init coresight_pm_setup(void) { - return cpu_pm_register_notifier(&coresight_cpu_pm_nb); + int ret; + + ret = cpu_pm_register_notifier(&coresight_cpu_pm_nb); + if (ret) + return ret; + + ret = cpuhp_setup_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING, + "arm/coresight-core:starting", + NULL, coresight_dying_cpu); + if (ret) + cpu_pm_unregister_notifier(&coresight_cpu_pm_nb); + + return ret; }
static void coresight_pm_cleanup(void) { + cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING); cpu_pm_unregister_notifier(&coresight_cpu_pm_nb); }
diff --git a/drivers/hwtracing/coresight/coresight-etm3x-core.c b/drivers/hwtracing/coresight/coresight-etm3x-core.c index 730d2584d625f11db87729352bcb80b9df1caa04..e05c752d57d9772e771b2df1bbf76e85623ea9ab 100644 --- a/drivers/hwtracing/coresight/coresight-etm3x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm3x-core.c @@ -701,35 +701,6 @@ static int etm_online_cpu(unsigned int cpu) return 0; }
-static int etm_starting_cpu(unsigned int cpu) -{ - if (!etmdrvdata[cpu]) - return 0; - - spin_lock(&etmdrvdata[cpu]->spinlock); - if (!etmdrvdata[cpu]->os_unlock) { - etm_os_unlock(etmdrvdata[cpu]); - etmdrvdata[cpu]->os_unlock = true; - } - - if (coresight_get_mode(etmdrvdata[cpu]->csdev)) - etm_enable_hw(etmdrvdata[cpu]); - spin_unlock(&etmdrvdata[cpu]->spinlock); - return 0; -} - -static int etm_dying_cpu(unsigned int cpu) -{ - if (!etmdrvdata[cpu]) - return 0; - - spin_lock(&etmdrvdata[cpu]->spinlock); - if (coresight_get_mode(etmdrvdata[cpu]->csdev)) - etm_disable_hw(etmdrvdata[cpu]); - spin_unlock(&etmdrvdata[cpu]->spinlock); - return 0; -} - static bool etm_arch_supported(u8 arch) { switch (arch) { @@ -797,13 +768,6 @@ static int __init etm_hp_setup(void) { int ret;
- ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ARM_CORESIGHT_STARTING, - "arm/coresight:starting", - etm_starting_cpu, etm_dying_cpu); - - if (ret) - return ret; - ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN, "arm/coresight:online", etm_online_cpu, NULL); @@ -814,15 +778,11 @@ static int __init etm_hp_setup(void) return 0; }
- /* failed dyn state - remove others */ - cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING); - return ret; }
static void etm_hp_clear(void) { - cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING); if (hp_online) { cpuhp_remove_state_nocalls(hp_online); hp_online = 0; diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c index 85f974f8635d0e0b548c7cb506c734a0c3d55f24..5bb4f8a40b78368cb61844cd800a6a42eeb48f87 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c @@ -1808,33 +1808,6 @@ static int etm4_online_cpu(unsigned int cpu) return 0; }
-static int etm4_starting_cpu(unsigned int cpu) -{ - if (!etmdrvdata[cpu]) - return 0; - - raw_spin_lock(&etmdrvdata[cpu]->spinlock); - if (!etmdrvdata[cpu]->os_unlock) - etm4_os_unlock(etmdrvdata[cpu]); - - if (coresight_get_mode(etmdrvdata[cpu]->csdev)) - etm4_enable_hw(etmdrvdata[cpu]); - raw_spin_unlock(&etmdrvdata[cpu]->spinlock); - return 0; -} - -static int etm4_dying_cpu(unsigned int cpu) -{ - if (!etmdrvdata[cpu]) - return 0; - - raw_spin_lock(&etmdrvdata[cpu]->spinlock); - if (coresight_get_mode(etmdrvdata[cpu]->csdev)) - etm4_disable_hw(etmdrvdata[cpu]); - raw_spin_unlock(&etmdrvdata[cpu]->spinlock); - return 0; -} - static bool etm4_need_save_restore_context(struct coresight_device *csdev) { if (pm_save_enable != PARAM_PM_SAVE_SELF_HOSTED) @@ -2107,13 +2080,6 @@ static int __init etm4_pm_setup(void) { int ret;
- ret = cpuhp_setup_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING, - "arm/coresight4:starting", - etm4_starting_cpu, etm4_dying_cpu); - - if (ret) - return ret; - ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "arm/coresight4:online", etm4_online_cpu, NULL); @@ -2124,14 +2090,11 @@ static int __init etm4_pm_setup(void) return 0; }
- /* failed dyn state - remove others */ - cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING); return ret; }
static void etm4_pm_clear(void) { - cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING); if (hp_online) { cpuhp_remove_state_nocalls(hp_online); hp_online = 0;