[PATCH 8/8] coresight: etm4x: implementing the perf PMU API
From: mathieu.poirier@linaro.org (Mathieu Poirier)
Date: 2016-02-29 18:55:00
Also in:
lkml
Subsystem:
arm/coresight framework and drivers, hardware tracing facilities, the rest · Maintainers:
Suzuki K Poulose, Alexander Shishkin, Linus Torvalds
Adding a set of API allowing the Perf core to treat ETMv4 tracers like other PMUs. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> --- drivers/hwtracing/coresight/Makefile | 5 +- drivers/hwtracing/coresight/coresight-etm4x.c | 85 +++++++++++++++++++++++++-- 2 files changed, 82 insertions(+), 8 deletions(-)
diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile
index 637ca978cd05..1d0e32c7dbe4 100644
--- a/drivers/hwtracing/coresight/Makefile
+++ b/drivers/hwtracing/coresight/Makefile@@ -1,7 +1,7 @@ # # Makefile for CoreSight drivers. # -obj-$(CONFIG_CORESIGHT) += coresight.o +obj-$(CONFIG_CORESIGHT) += coresight.o coresight-etm-perf.o obj-$(CONFIG_OF) += of_coresight.o obj-$(CONFIG_CORESIGHT_LINK_AND_SINK_TMC) += coresight-tmc.o obj-$(CONFIG_CORESIGHT_SINK_TPIU) += coresight-tpiu.o
@@ -9,8 +9,7 @@ obj-$(CONFIG_CORESIGHT_SINK_ETBV10) += coresight-etb10.o obj-$(CONFIG_CORESIGHT_LINKS_AND_SINKS) += coresight-funnel.o \ coresight-replicator.o obj-$(CONFIG_CORESIGHT_SOURCE_ETM3X) += coresight-etm3x.o coresight-etm-cp14.o \ - coresight-etm3x-sysfs.o \ - coresight-etm-perf.o + coresight-etm3x-sysfs.o obj-$(CONFIG_CORESIGHT_SOURCE_ETM4X) += coresight-etm4x.o \ coresight-etm4x-sysfs.o obj-$(CONFIG_CORESIGHT_QCOM_REPLICATOR) += coresight-replicator-qcom.o
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 743c34b92a80..8bd400cce904 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c@@ -32,12 +32,14 @@ #include <linux/amba/bus.h> #include <linux/seq_file.h> #include <linux/uaccess.h> +#include <linux/perf_event.h> #include <linux/pm_runtime.h> #include <linux/perf_event.h> #include <asm/sections.h> #include <asm/local.h> #include "coresight-etm4x.h" +#include "coresight-etm-perf.h" static int boot_enable; module_param_named(boot_enable, boot_enable, int, S_IRUGO);
@@ -45,6 +47,7 @@ module_param_named(boot_enable, boot_enable, int, S_IRUGO); /* The number of ETMv4 currently registered */ static int etm4_count; static struct etmv4_drvdata *etmdrvdata[NR_CPUS]; +static void etm4_set_default(struct etmv4_config *config); static void etm4_os_unlock(struct etmv4_drvdata *drvdata) {
@@ -190,6 +193,58 @@ static void etm4_enable_hw(void *info) dev_dbg(drvdata->dev, "cpu: %d enable smp call done\n", drvdata->cpu); } +static int etm4_parse_event_config(struct etmv4_drvdata *drvdata, + struct perf_event_attr *attr) +{ + struct etmv4_config *config = &drvdata->config; + + if (!attr) + return -EINVAL; + + /* Clear configuration from previous run */ + memset(config, 0, sizeof(struct etmv4_config)); + + if (attr->exclude_kernel) + config->mode = ETM_MODE_EXCL_KERN; + + if (attr->exclude_user) + config->mode = ETM_MODE_EXCL_USER; + + /* Always start from the default config */ + etm4_set_default(config); + + /* + * By default the tracers are configured to trace the whole address + * range. Narrow the field only if requested by user space. + */ + if (config->mode) + etm4_config_trace_mode(config); + + /* Go from generic option to ETMv4 specifics */ + if (attr->config & BIT(ETM_OPT_CYCACC)) + config->cfg |= ETMv4_MODE_CYCACC; + if (attr->config & BIT(ETM_OPT_TS)) + config->cfg |= ETMv4_MODE_TIMESTAMP; + + return 0; +} + +static int etm4_enable_perf(struct coresight_device *csdev, + struct perf_event_attr *attr) +{ + struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); + + if (WARN_ON_ONCE(drvdata->cpu != smp_processor_id())) + return -EINVAL; + + /* Configure the tracer based on the session's specifics */ + etm4_parse_event_config(drvdata, attr); + /* And enable it */ + etm4_enable_hw(drvdata); + + return 0; +} + static int etm4_enable_sysfs(struct coresight_device *csdev) { struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
@@ -234,6 +289,9 @@ static int etm4_enable(struct coresight_device *csdev, case CS_MODE_SYSFS: ret = etm4_enable_sysfs(csdev); break; + case CS_MODE_PERF: + ret = etm4_enable_perf(csdev, attr); + break; default: ret = -EINVAL; }
@@ -267,6 +325,17 @@ static void etm4_disable_hw(void *info) dev_dbg(drvdata->dev, "cpu: %d disable smp call done\n", drvdata->cpu); } +static int etm4_disable_perf(struct coresight_device *csdev) +{ + struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); + + if (WARN_ON_ONCE(drvdata->cpu != smp_processor_id())) + return -EINVAL; + + etm4_disable_hw(drvdata); + return 0; +} + static void etm4_disable_sysfs(struct coresight_device *csdev) { struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
@@ -310,6 +379,9 @@ static void etm4_disable(struct coresight_device *csdev) case CS_MODE_SYSFS: etm4_disable_sysfs(csdev); break; + case CS_MODE_PERF: + etm4_disable_perf(csdev); + break; } if (mode)
@@ -709,8 +781,6 @@ static int etm4_probe(struct amba_device *adev, const struct amba_id *id) etm4_init_trace_id(drvdata); etm4_set_default(&drvdata->config); - pm_runtime_put(&adev->dev); - desc->type = CORESIGHT_DEV_TYPE_SOURCE; desc->subtype.source_subtype = CORESIGHT_DEV_SUBTYPE_SOURCE_PROC; desc->ops = &etm4_cs_ops;
@@ -720,9 +790,16 @@ static int etm4_probe(struct amba_device *adev, const struct amba_id *id) drvdata->csdev = coresight_register(desc); if (IS_ERR(drvdata->csdev)) { ret = PTR_ERR(drvdata->csdev); - goto err_coresight_register; + goto err_arch_supported; } + ret = etm_perf_symlink(drvdata->csdev, true); + if (ret) { + coresight_unregister(drvdata->csdev); + goto err_arch_supported; + } + + pm_runtime_put(&adev->dev); dev_info(dev, "%s initialized\n", (char *)id->data); if (boot_enable) {
@@ -733,8 +810,6 @@ static int etm4_probe(struct amba_device *adev, const struct amba_id *id) return 0; err_arch_supported: - pm_runtime_put(&adev->dev); -err_coresight_register: if (--etm4_count == 0) unregister_hotcpu_notifier(&etm4_cpu_notifier); return ret;
--
2.1.4