diff options
| -rw-r--r-- | drivers/hwtracing/coresight/coresight-etm-perf.c | 55 |
1 files changed, 40 insertions, 15 deletions
diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c index 677695635211..6338dd180031 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.c +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c @@ -12,6 +12,7 @@ #include <linux/mm.h> #include <linux/init.h> #include <linux/perf_event.h> +#include <linux/percpu-defs.h> #include <linux/slab.h> #include <linux/types.h> #include <linux/workqueue.h> @@ -33,7 +34,7 @@ struct etm_event_data { struct work_struct work; cpumask_t mask; void *snk_config; - struct list_head **path; + struct list_head * __percpu *path; }; static DEFINE_PER_CPU(struct perf_output_handle, ctx_handle); @@ -61,6 +62,18 @@ static const struct attribute_group *etm_pmu_attr_groups[] = { NULL, }; +static inline struct list_head ** +etm_event_cpu_path_ptr(struct etm_event_data *data, int cpu) +{ + return per_cpu_ptr(data->path, cpu); +} + +static inline struct list_head * +etm_event_cpu_path(struct etm_event_data *data, int cpu) +{ + return *etm_event_cpu_path_ptr(data, cpu); +} + static void etm_event_read(struct perf_event *event) {} static int etm_addr_filters_alloc(struct perf_event *event) @@ -120,23 +133,26 @@ static void free_event_data(struct work_struct *work) */ if (event_data->snk_config) { cpu = cpumask_first(mask); - sink = coresight_get_sink(event_data->path[cpu]); + sink = coresight_get_sink(etm_event_cpu_path(event_data, cpu)); if (sink_ops(sink)->free_buffer) sink_ops(sink)->free_buffer(event_data->snk_config); } for_each_cpu(cpu, mask) { - if (!(IS_ERR_OR_NULL(event_data->path[cpu]))) - coresight_release_path(event_data->path[cpu]); + struct list_head **ppath; + + ppath = etm_event_cpu_path_ptr(event_data, cpu); + if (!(IS_ERR_OR_NULL(*ppath))) + coresight_release_path(*ppath); + *ppath = NULL; } - kfree(event_data->path); + free_percpu(event_data->path); kfree(event_data); } static void *alloc_event_data(int cpu) { - int size; cpumask_t *mask; struct etm_event_data *event_data; @@ -147,7 +163,6 @@ static void *alloc_event_data(int cpu) /* Make sure nothing disappears under us */ get_online_cpus(); - size = num_online_cpus(); mask = &event_data->mask; if (cpu != -1) @@ -164,8 +179,8 @@ static void *alloc_event_data(int cpu) * unused memory when dealing with single CPU trace scenarios is small * compared to the cost of searching through an optimized array. */ - event_data->path = kcalloc(size, - sizeof(struct list_head *), GFP_KERNEL); + event_data->path = alloc_percpu(struct list_head *); + if (!event_data->path) { kfree(event_data); return NULL; @@ -213,6 +228,7 @@ static void *etm_setup_aux(int event_cpu, void **pages, /* Setup the path for each CPU in a trace session */ for_each_cpu(cpu, mask) { + struct list_head *path; struct coresight_device *csdev; csdev = per_cpu(csdev_src, cpu); @@ -224,9 +240,11 @@ static void *etm_setup_aux(int event_cpu, void **pages, * list of devices from source to sink that can be * referenced later when the path is actually needed. */ - event_data->path[cpu] = coresight_build_path(csdev, sink); - if (IS_ERR(event_data->path[cpu])) + path = coresight_build_path(csdev, sink); + if (IS_ERR(path)) goto err; + + *etm_event_cpu_path_ptr(event_data, cpu) = path; } if (!sink_ops(sink)->alloc_buffer) @@ -255,6 +273,7 @@ static void etm_event_start(struct perf_event *event, int flags) struct etm_event_data *event_data; struct perf_output_handle *handle = this_cpu_ptr(&ctx_handle); struct coresight_device *sink, *csdev = per_cpu(csdev_src, cpu); + struct list_head *path; if (!csdev) goto fail; @@ -267,8 +286,9 @@ static void etm_event_start(struct perf_event *event, int flags) if (!event_data) goto fail; + path = etm_event_cpu_path(event_data, cpu); /* We need a sink, no need to continue without one */ - sink = coresight_get_sink(event_data->path[cpu]); + sink = coresight_get_sink(path); if (WARN_ON_ONCE(!sink || !sink_ops(sink)->set_buffer)) goto fail_end_stop; @@ -278,7 +298,7 @@ static void etm_event_start(struct perf_event *event, int flags) goto fail_end_stop; /* Nothing will happen without a path */ - if (coresight_enable_path(event_data->path[cpu], CS_MODE_PERF)) + if (coresight_enable_path(path, CS_MODE_PERF)) goto fail_end_stop; /* Tell the perf core the event is alive */ @@ -306,6 +326,7 @@ static void etm_event_stop(struct perf_event *event, int mode) struct coresight_device *sink, *csdev = per_cpu(csdev_src, cpu); struct perf_output_handle *handle = this_cpu_ptr(&ctx_handle); struct etm_event_data *event_data = perf_get_aux(handle); + struct list_head *path; if (event->hw.state == PERF_HES_STOPPED) return; @@ -313,7 +334,11 @@ static void etm_event_stop(struct perf_event *event, int mode) if (!csdev) return; - sink = coresight_get_sink(event_data->path[cpu]); + path = etm_event_cpu_path(event_data, cpu); + if (!path) + return; + + sink = coresight_get_sink(path); if (!sink) return; @@ -344,7 +369,7 @@ static void etm_event_stop(struct perf_event *event, int mode) } /* Disabling the path make its elements available to other sessions */ - coresight_disable_path(event_data->path[cpu]); + coresight_disable_path(path); } static int etm_event_add(struct perf_event *event, int mode) |