diff options
| -rw-r--r-- | arch/powerpc/perf/vpa-dtl.c | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/arch/powerpc/perf/vpa-dtl.c b/arch/powerpc/perf/vpa-dtl.c index 4a8ba5b3ae3f..28e7fc6e7015 100644 --- a/arch/powerpc/perf/vpa-dtl.c +++ b/arch/powerpc/perf/vpa-dtl.c @@ -11,6 +11,7 @@ #include <asm/dtl.h> #include <linux/perf_event.h> #include <asm/plpar_wrappers.h> +#include <linux/vmalloc.h> #define EVENT(_name, _code) enum{_name = _code} @@ -74,6 +75,19 @@ struct vpa_dtl { u64 last_idx; }; +struct vpa_pmu_ctx { + struct perf_output_handle handle; +}; + +struct vpa_pmu_buf { + int nr_pages; + bool snapshot; + u64 *base; + u64 size; + u64 head; +}; + +static DEFINE_PER_CPU(struct vpa_pmu_ctx, vpa_pmu_ctx); static DEFINE_PER_CPU(struct vpa_dtl, vpa_dtl_cpu); /* variable to capture reference count for the active dtl threads */ @@ -302,6 +316,67 @@ static void vpa_dtl_event_read(struct perf_event *event) { } +/* + * Set up pmu-private data structures for an AUX area + * **pages contains the aux buffer allocated for this event + * for the corresponding cpu. rb_alloc_aux uses "alloc_pages_node" + * and returns pointer to each page address. Map these pages to + * contiguous space using vmap and use that as base address. + * + * The aux private data structure ie, "struct vpa_pmu_buf" mainly + * saves + * - buf->base: aux buffer base address + * - buf->head: offset from base address where data will be written to. + * - buf->size: Size of allocated memory + */ +static void *vpa_dtl_setup_aux(struct perf_event *event, void **pages, + int nr_pages, bool snapshot) +{ + int i, cpu = event->cpu; + struct vpa_pmu_buf *buf __free(kfree) = NULL; + struct page **pglist __free(kfree) = NULL; + + /* We need at least one page for this to work. */ + if (!nr_pages) + return NULL; + + if (cpu == -1) + cpu = raw_smp_processor_id(); + + buf = kzalloc_node(sizeof(*buf), GFP_KERNEL, cpu_to_node(cpu)); + if (!buf) + return NULL; + + pglist = kcalloc(nr_pages, sizeof(*pglist), GFP_KERNEL); + if (!pglist) + return NULL; + + for (i = 0; i < nr_pages; ++i) + pglist[i] = virt_to_page(pages[i]); + + buf->base = vmap(pglist, nr_pages, VM_MAP, PAGE_KERNEL); + if (!buf->base) + return NULL; + + buf->nr_pages = nr_pages; + buf->snapshot = false; + + buf->size = nr_pages << PAGE_SHIFT; + buf->head = 0; + return no_free_ptr(buf); +} + +/* + * free pmu-private AUX data structures + */ +static void vpa_dtl_free_aux(void *aux) +{ + struct vpa_pmu_buf *buf = aux; + + vunmap(buf->base); + kfree(buf); +} + static struct pmu vpa_dtl_pmu = { .task_ctx_nr = perf_invalid_context, @@ -311,6 +386,8 @@ static struct pmu vpa_dtl_pmu = { .add = vpa_dtl_event_add, .del = vpa_dtl_event_del, .read = vpa_dtl_event_read, + .setup_aux = vpa_dtl_setup_aux, + .free_aux = vpa_dtl_free_aux, .capabilities = PERF_PMU_CAP_NO_EXCLUDE | PERF_PMU_CAP_EXCLUSIVE, }; |