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 Reviewed-by: Yeoreum Yun yeoreum.yun@arm.com Reviewed-by: James Clark james.clark@linaro.org Signed-off-by: Leo Yan leo.yan@arm.com --- drivers/hwtracing/coresight/coresight-core.c | 36 ++++++++++++++++++- drivers/hwtracing/coresight/coresight-etm3x-core.c | 40 ---------------------- drivers/hwtracing/coresight/coresight-etm4x-core.c | 37 -------------------- 3 files changed, 35 insertions(+), 78 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c index a41e77da4f083d4b5d162e7b70905f22bddf7ca2..5ebe0640129ade401de9d2ebb97819c6d1809d83 100644 --- a/drivers/hwtracing/coresight/coresight-core.c +++ b/drivers/hwtracing/coresight/coresight-core.c @@ -1847,13 +1847,47 @@ static struct notifier_block coresight_cpu_pm_nb = { .notifier_call = coresight_cpu_pm_notify, };
+static int coresight_dying_cpu(unsigned int cpu) +{ + struct coresight_path *path = coresight_get_percpu_local_path(); + struct coresight_device *source = coresight_get_source(path); + + if (!path || !source) + 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; + + coresight_disable_source(source, NULL); + coresight_disable_path(path); + coresight_release_path(path); + return 0; +} + 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 46ea66b5cf1985bd7129688f175f6f92372d04ad..5c6b131465c52fd8ab9161bf36fc78ba9a7dd99b 100644 --- a/drivers/hwtracing/coresight/coresight-etm3x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm3x-core.c @@ -699,35 +699,6 @@ 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) { @@ -795,13 +766,6 @@ static int __init etm_hp_setup(void) { int ret;
- ret = cpuhp_setup_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING, - "arm/coresight:starting", - etm_starting_cpu, etm_dying_cpu); - - if (ret) - return ret; - ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "arm/coresight:online", etm_online_cpu, NULL); @@ -812,15 +776,11 @@ 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 087a32fe34890528c6fa6ada601aeb742f04c41b..a10a40098659e9814b4d20c15f01bf7d0c2fbe26 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c @@ -1834,33 +1834,6 @@ 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 int etm4_cpu_save(struct coresight_device *csdev) { int i, ret = 0; @@ -2110,13 +2083,6 @@ 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); @@ -2127,14 +2093,11 @@ 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;