diff options
Diffstat (limited to 'arch/x86/events/intel/bts.c')
| -rw-r--r-- | arch/x86/events/intel/bts.c | 45 |
1 files changed, 32 insertions, 13 deletions
diff --git a/arch/x86/events/intel/bts.c b/arch/x86/events/intel/bts.c index 8f78b0c900ef..a95e6c91c4d7 100644 --- a/arch/x86/events/intel/bts.c +++ b/arch/x86/events/intel/bts.c @@ -36,7 +36,7 @@ enum { BTS_STATE_ACTIVE, }; -static DEFINE_PER_CPU(struct bts_ctx, bts_ctx); +static struct bts_ctx __percpu *bts_ctx; #define BTS_RECORD_SIZE 24 #define BTS_SAFETY_MARGIN 4080 @@ -58,7 +58,7 @@ struct bts_buffer { local_t head; unsigned long end; void **data_pages; - struct bts_phys buf[]; + struct bts_phys buf[] __counted_by(nr_bufs); }; static struct pmu bts_pmu; @@ -231,7 +231,7 @@ bts_buffer_reset(struct bts_buffer *buf, struct perf_output_handle *handle); static void __bts_event_start(struct perf_event *event) { - struct bts_ctx *bts = this_cpu_ptr(&bts_ctx); + struct bts_ctx *bts = this_cpu_ptr(bts_ctx); struct bts_buffer *buf = perf_get_aux(&bts->handle); u64 config = 0; @@ -260,7 +260,7 @@ static void __bts_event_start(struct perf_event *event) static void bts_event_start(struct perf_event *event, int flags) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); - struct bts_ctx *bts = this_cpu_ptr(&bts_ctx); + struct bts_ctx *bts = this_cpu_ptr(bts_ctx); struct bts_buffer *buf; buf = perf_aux_output_begin(&bts->handle, event); @@ -290,7 +290,7 @@ fail_stop: static void __bts_event_stop(struct perf_event *event, int state) { - struct bts_ctx *bts = this_cpu_ptr(&bts_ctx); + struct bts_ctx *bts = this_cpu_ptr(bts_ctx); /* ACTIVE -> INACTIVE(PMI)/STOPPED(->stop()) */ WRITE_ONCE(bts->state, state); @@ -305,7 +305,7 @@ static void __bts_event_stop(struct perf_event *event, int state) static void bts_event_stop(struct perf_event *event, int flags) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); - struct bts_ctx *bts = this_cpu_ptr(&bts_ctx); + struct bts_ctx *bts = this_cpu_ptr(bts_ctx); struct bts_buffer *buf = NULL; int state = READ_ONCE(bts->state); @@ -338,9 +338,14 @@ static void bts_event_stop(struct perf_event *event, int flags) void intel_bts_enable_local(void) { - struct bts_ctx *bts = this_cpu_ptr(&bts_ctx); - int state = READ_ONCE(bts->state); + struct bts_ctx *bts; + int state; + + if (!bts_ctx) + return; + bts = this_cpu_ptr(bts_ctx); + state = READ_ONCE(bts->state); /* * Here we transition from INACTIVE to ACTIVE; * if we instead are STOPPED from the interrupt handler, @@ -358,7 +363,12 @@ void intel_bts_enable_local(void) void intel_bts_disable_local(void) { - struct bts_ctx *bts = this_cpu_ptr(&bts_ctx); + struct bts_ctx *bts; + + if (!bts_ctx) + return; + + bts = this_cpu_ptr(bts_ctx); /* * Here we transition from ACTIVE to INACTIVE; @@ -450,12 +460,17 @@ bts_buffer_reset(struct bts_buffer *buf, struct perf_output_handle *handle) int intel_bts_interrupt(void) { struct debug_store *ds = this_cpu_ptr(&cpu_hw_events)->ds; - struct bts_ctx *bts = this_cpu_ptr(&bts_ctx); - struct perf_event *event = bts->handle.event; + struct bts_ctx *bts; + struct perf_event *event; struct bts_buffer *buf; s64 old_head; int err = -ENOSPC, handled = 0; + if (!bts_ctx) + return 0; + + bts = this_cpu_ptr(bts_ctx); + event = bts->handle.event; /* * The only surefire way of knowing if this NMI is ours is by checking * the write ptr against the PMI threshold. @@ -518,7 +533,7 @@ static void bts_event_del(struct perf_event *event, int mode) static int bts_event_add(struct perf_event *event, int mode) { - struct bts_ctx *bts = this_cpu_ptr(&bts_ctx); + struct bts_ctx *bts = this_cpu_ptr(bts_ctx); struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); struct hw_perf_event *hwc = &event->hw; @@ -559,7 +574,7 @@ static int bts_event_init(struct perf_event *event) * to the user in a zero-copy fashion. */ if (event->attr.exclude_kernel) { - ret = perf_allow_kernel(&event->attr); + ret = perf_allow_kernel(); if (ret) return ret; } @@ -605,6 +620,10 @@ static __init int bts_init(void) return -ENODEV; } + bts_ctx = alloc_percpu(struct bts_ctx); + if (!bts_ctx) + return -ENOMEM; + bts_pmu.capabilities = PERF_PMU_CAP_AUX_NO_SG | PERF_PMU_CAP_ITRACE | PERF_PMU_CAP_EXCLUSIVE; bts_pmu.task_ctx_nr = perf_sw_context; |