Re: [PATCH v8 10/24] coresight: etm4x: allow etm4x to be built as a module
From: Tingwei Zhang <hidden>
Date: 2020-08-13 23:59:34
On Fri, Aug 14, 2020 at 03:45:06AM +0800, Mathieu Poirier wrote:
On Fri, Aug 07, 2020 at 07:11:39PM +0800, Tingwei Zhang wrote:quoted
From: Kim Phillips <redacted> Allow to build coresight-etm4x as a module, for ease of development. - Kconfig becomes a tristate, to allow =m - append -core to source file name to allow module to be called coresight-etm4x by the Makefile - add an etm4_remove function, for module unload - add a MODULE_DEVICE_TABLE for autoloading on boot - protect etmdrvdata[] with mutex lock from racing between module unload and CPU hotplug Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Leo Yan <redacted> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Randy Dunlap <redacted> Cc: Suzuki K Poulose <Suzuki.Poulose@arm.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Russell King <linux@armlinux.org.uk> Signed-off-by: Kim Phillips <redacted> Signed-off-by: Tingwei Zhang <redacted> Tested-by: Mike Leach <redacted> --- drivers/hwtracing/coresight/Kconfig | 5 +- drivers/hwtracing/coresight/Makefile | 4 +- ...resight-etm4x.c => coresight-etm4x-core.c} | 118 +++++++++++++----- 3 files changed, 92 insertions(+), 35 deletions(-) rename drivers/hwtracing/coresight/{coresight-etm4x.c =>coresight-etm4x-core.c} (95%)quoted
diff --git a/drivers/hwtracing/coresight/Kconfigb/drivers/hwtracing/coresight/Kconfigquoted
index 8fd9fd139cf3..d6e107bbd30b 100644--- a/drivers/hwtracing/coresight/Kconfig +++ b/drivers/hwtracing/coresight/Kconfig@@ -78,7 +78,7 @@ config CORESIGHT_SOURCE_ETM3X module will be called coresight-etm3x. config CORESIGHT_SOURCE_ETM4X - bool "CoreSight Embedded Trace Macrocell 4.x driver" + tristate "CoreSight Embedded Trace Macrocell 4.x driver" depends on ARM64 select CORESIGHT_LINKS_AND_SINKS select PID_IN_CONTEXTIDR@@ -88,6 +88,9 @@ config CORESIGHT_SOURCE_ETM4X for instruction level tracing. Depending on the implementedversionquoted
data tracing may also be available. + To compile this driver as a module, choose M here: the + module will be called coresight-etm4x. + config CORESIGHT_STM tristate "CoreSight System Trace Macrocell driver" depends on (ARM && !(CPU_32v3 || CPU_32v4 || CPU_32v4T)) || ARM64diff --git a/drivers/hwtracing/coresight/Makefileb/drivers/hwtracing/coresight/Makefilequoted
index d619cfd0abd8..271dc255454f 100644--- a/drivers/hwtracing/coresight/Makefile +++ b/drivers/hwtracing/coresight/Makefile@@ -14,8 +14,8 @@ obj-$(CONFIG_CORESIGHT_LINKS_AND_SINKS) +=coresight-funnel.o \quoted
obj-$(CONFIG_CORESIGHT_SOURCE_ETM3X) += coresight-etm3x.o coresight-etm3x-y := coresight-etm3x-core.o coresight-etm-cp14.o \ coresight-etm3x-sysfs.o -obj-$(CONFIG_CORESIGHT_SOURCE_ETM4X) += coresight-etm4x.o \ - coresight-etm4x-sysfs.o +obj-$(CONFIG_CORESIGHT_SOURCE_ETM4X) += coresight-etm4x.o +coresight-etm4x-y := coresight-etm4x-core.o coresight-etm4x-sysfs.o obj-$(CONFIG_CORESIGHT_STM) += coresight-stm.o obj-$(CONFIG_CORESIGHT_CPU_DEBUG) += coresight-cpu-debug.o obj-$(CONFIG_CORESIGHT_CATU) += coresight-catu.odiff --git a/drivers/hwtracing/coresight/coresight-etm4x.cb/drivers/hwtracing/coresight/coresight-etm4x-core.cquoted
similarity index 95% rename from drivers/hwtracing/coresight/coresight-etm4x.c rename to drivers/hwtracing/coresight/coresight-etm4x-core.c index fddfd93b9a7b..ae9847e194a3 100644--- a/drivers/hwtracing/coresight/coresight-etm4x.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c@@ -48,6 +48,7 @@ module_param(pm_save_enable, int, 0444); MODULE_PARM_DESC(pm_save_enable, "Save/restore state on power down: 1 = never, 2 = self-hosted"); +static DEFINE_PER_CPU(struct mutex, etmdrvdata_lock); static struct etmv4_drvdata *etmdrvdata[NR_CPUS]; static void etm4_set_default_config(struct etmv4_config *config); static int etm4_set_event_filters(struct etmv4_drvdata *drvdata,@@ -1089,18 +1090,25 @@ void etm4_config_trace_mode(struct etmv4_config*config)quoted
static int etm4_online_cpu(unsigned int cpu) { - if (!etmdrvdata[cpu]) + mutex_lock(&per_cpu(etmdrvdata_lock, cpu)); + if (!etmdrvdata[cpu]) { + mutex_unlock(&per_cpu(etmdrvdata_lock, cpu)); return 0; + } if (etmdrvdata[cpu]->boot_enable &&!etmdrvdata[cpu]->sticky_enable)quoted
coresight_enable(etmdrvdata[cpu]->csdev); + mutex_unlock(&per_cpu(etmdrvdata_lock, cpu)); return 0; } static int etm4_starting_cpu(unsigned int cpu) { - if (!etmdrvdata[cpu]) + mutex_lock(&per_cpu(etmdrvdata_lock, cpu)); + if (!etmdrvdata[cpu]) { + mutex_unlock(&per_cpu(etmdrvdata_lock, cpu)); return 0; + } spin_lock(&etmdrvdata[cpu]->spinlock); if (!etmdrvdata[cpu]->os_unlock)@@ -1109,18 +1117,23 @@ static int etm4_starting_cpu(unsigned int cpu) if (local_read(&etmdrvdata[cpu]->mode)) etm4_enable_hw(etmdrvdata[cpu]); spin_unlock(&etmdrvdata[cpu]->spinlock); + mutex_unlock(&per_cpu(etmdrvdata_lock, cpu)); return 0; } static int etm4_dying_cpu(unsigned int cpu) { - if (!etmdrvdata[cpu]) + mutex_lock(&per_cpu(etmdrvdata_lock, cpu)); + if (!etmdrvdata[cpu]) { + mutex_unlock(&per_cpu(etmdrvdata_lock, cpu)); return 0; + } spin_lock(&etmdrvdata[cpu]->spinlock); if (local_read(&etmdrvdata[cpu]->mode)) etm4_disable_hw(etmdrvdata[cpu]); spin_unlock(&etmdrvdata[cpu]->spinlock); + mutex_unlock(&per_cpu(etmdrvdata_lock, cpu)); return 0; }@@ -1360,24 +1373,30 @@ static int etm4_cpu_pm_notify(structnotifier_block *nb, unsigned long cmd,quoted
{ struct etmv4_drvdata *drvdata; unsigned int cpu = smp_processor_id(); + int ret = NOTIFY_OK; + mutex_lock(&per_cpu(etmdrvdata_lock, cpu)); if (!etmdrvdata[cpu]) - return NOTIFY_OK; + goto out; drvdata = etmdrvdata[cpu]; if (!drvdata->save_state) - return NOTIFY_OK; + goto out; - if (WARN_ON_ONCE(drvdata->cpu != cpu)) - return NOTIFY_BAD; + if (WARN_ON_ONCE(drvdata->cpu != cpu)) { + ret = NOTIFY_BAD; + goto out; + } switch (cmd) { case CPU_PM_ENTER: /* save the state if self-hosted coresight is in use */ if (local_read(&drvdata->mode)) - if (etm4_cpu_save(drvdata)) - return NOTIFY_BAD; + if (etm4_cpu_save(drvdata)) { + ret = NOTIFY_BAD; + goto out; + } break; case CPU_PM_EXIT: /* fallthrough */@@ -1386,10 +1405,12 @@ static int etm4_cpu_pm_notify(structnotifier_block *nb, unsigned long cmd,quoted
etm4_cpu_restore(drvdata); break; default: - return NOTIFY_DONE; + goto out; } - return NOTIFY_OK; +out: + mutex_unlock(&per_cpu(etmdrvdata_lock, cpu)); + return ret; } static struct notifier_block etm4_cpu_pm_nb = {@@ -1430,7 +1451,7 @@ static int __init etm4_pm_setup(void) return ret; } -static void __init etm4_pm_clear(void) +static void etm4_pm_clear(void) { cpu_pm_unregister_notifier(&etm4_cpu_pm_nb); cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING);@@ -1487,25 +1508,20 @@ static int etm4_probe(struct amba_device *adev,const struct amba_id *id)quoted
if (!desc.name) return -ENOMEM; - etmdrvdata[drvdata->cpu] = drvdata; - if (smp_call_function_single(drvdata->cpu, etm4_init_arch_data, drvdata, 1)) dev_err(dev, "ETM arch init failed\n"); - if (etm4_arch_supported(drvdata->arch) == false) { - ret = -EINVAL; - goto err_arch_supported; - } + if (etm4_arch_supported(drvdata->arch) == false) + return -EINVAL; etm4_init_trace_id(drvdata); etm4_set_default(&drvdata->config); pdata = coresight_get_platform_data(dev); - if (IS_ERR(pdata)) { - ret = PTR_ERR(pdata); - goto err_arch_supported; - } + if (IS_ERR(pdata)) + return PTR_ERR(pdata); + adev->dev.platform_data = pdata; desc.type = CORESIGHT_DEV_TYPE_SOURCE;@@ -1515,17 +1531,19 @@ static int etm4_probe(struct amba_device *adev,const struct amba_id *id)quoted
desc.dev = dev; desc.groups = coresight_etmv4_groups; drvdata->csdev = coresight_register(&desc); - if (IS_ERR(drvdata->csdev)) { - ret = PTR_ERR(drvdata->csdev); - goto err_arch_supported; - } + if (IS_ERR(drvdata->csdev)) + return PTR_ERR(drvdata->csdev); ret = etm_perf_symlink(drvdata->csdev, true); if (ret) { coresight_unregister(drvdata->csdev); - goto err_arch_supported; + return ret; } + mutex_lock(&per_cpu(etmdrvdata_lock, drvdata->cpu)); + etmdrvdata[drvdata->cpu] = drvdata; + mutex_unlock(&per_cpu(etmdrvdata_lock, drvdata->cpu)); + pm_runtime_put(&adev->dev); dev_info(&drvdata->csdev->dev, "CPU%d: ETM v%d.%d initialized\n", drvdata->cpu, drvdata->arch >> 4, drvdata->arch & 0xf);@@ -1536,10 +1554,6 @@ static int etm4_probe(struct amba_device *adev,const struct amba_id *id)quoted
} return 0; - -err_arch_supported: - etmdrvdata[drvdata->cpu] = NULL; - return ret; } static struct amba_cs_uci_id uci_id_etm4[] = {@@ -1551,6 +1565,22 @@ static struct amba_cs_uci_id uci_id_etm4[] = { } }; +static int __exit etm4_remove(struct amba_device *adev) +{ + struct etmv4_drvdata *drvdata = dev_get_drvdata(&adev->dev); + + etm_perf_symlink(drvdata->csdev, false); + + mutex_lock(&per_cpu(etmdrvdata_lock, drvdata->cpu)); + etmdrvdata[drvdata->cpu] = NULL; + mutex_unlock(&per_cpu(etmdrvdata_lock, drvdata->cpu)); + + coresight_unregister(drvdata->csdev); + + return 0; +} + +Extra line
Will fix in next revision.
quoted
static const struct amba_id etm4_ids[] = { CS_AMBA_ID(0x000bb95d), /* Cortex-A53 */ CS_AMBA_ID(0x000bb95e), /* Cortex-A57 */@@ -1568,18 +1598,26 @@ static const struct amba_id etm4_ids[] = { {}, }; +MODULE_DEVICE_TABLE(amba, etm4_ids); + static struct amba_driver etm4x_driver = { .drv = { .name = "coresight-etm4x", + .owner = THIS_MODULE, .suppress_bind_attrs = true, }, .probe = etm4_probe, + .remove = etm4_remove, .id_table = etm4_ids, }; static int __init etm4x_init(void) { int ret; + int cpu; + + for_each_possible_cpu(cpu) + mutex_init(&per_cpu(etmdrvdata_lock, cpu)); ret = etm4_pm_setup();@@ -1595,4 +1633,20 @@ static int __init etm4x_init(void) return ret; } -device_initcall(etm4x_init); + +static void __exit etm4x_exit(void) +{ + int cpu; + + amba_driver_unregister(&etm4x_driver); + etm4_pm_clear(); + for_each_possible_cpu(cpu) + mutex_destroy(&per_cpu(etmdrvdata_lock, cpu)); +} +module_init(etm4x_init); +module_exit(etm4x_exit); + +MODULE_AUTHOR("Pratik Patel <pratikp@codeaurora.org>"); +MODULE_AUTHOR("Mathieu Poirier <mathieu.poirier@linaro.org>"); +MODULE_DESCRIPTION("Arm CoreSight Program Flow Trace v4 driver"); +MODULE_LICENSE("GPL v2");-- The Qualcomm Innovation Center, Inc. is a member of the Code AuroraForum,quoted
a Linux Foundation Collaborative Project
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