From 68db7e98c3a6ebe7284b6cf14906ed7c55f3f7f0 Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Wed, 14 Jan 2015 14:18:15 +0200 Subject: [PATCH] perf: Add AUX record When there's new data in the AUX space, output a record indicating its offset and size and a set of flags, such as PERF_AUX_FLAG_TRUNCATED, to mean the described data was truncated to fit in the ring buffer. Signed-off-by: Alexander Shishkin Signed-off-by: Peter Zijlstra (Intel) Cc: Arnaldo Carvalho de Melo Cc: Borislav Petkov Cc: Frederic Weisbecker Cc: H. Peter Anvin Cc: Kaixu Xia Cc: Linus Torvalds Cc: Mike Galbraith Cc: Paul Mackerras Cc: Robert Richter Cc: Stephane Eranian Cc: Thomas Gleixner Cc: adrian.hunter@intel.com Cc: kan.liang@intel.com Cc: markus.t.metzger@intel.com Cc: mathieu.poirier@linaro.org Link: http://lkml.kernel.org/r/1421237903-181015-7-git-send-email-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar --- include/uapi/linux/perf_event.h | 19 ++++++++++++++++++ kernel/events/core.c | 34 +++++++++++++++++++++++++++++++++ kernel/events/internal.h | 3 +++ 3 files changed, 56 insertions(+) diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h index 6c5013a71714..8904ad3a850b 100644 --- a/include/uapi/linux/perf_event.h +++ b/include/uapi/linux/perf_event.h @@ -768,6 +768,20 @@ enum perf_event_type { */ PERF_RECORD_MMAP2 = 10, + /* + * Records that new data landed in the AUX buffer part. + * + * struct { + * struct perf_event_header header; + * + * u64 aux_offset; + * u64 aux_size; + * u64 flags; + * struct sample_id sample_id; + * }; + */ + PERF_RECORD_AUX = 11, + PERF_RECORD_MAX, /* non-ABI */ }; @@ -785,6 +799,11 @@ enum perf_callchain_context { PERF_CONTEXT_MAX = (__u64)-4095, }; +/** + * PERF_RECORD_AUX::flags bits + */ +#define PERF_AUX_FLAG_TRUNCATED 0x01 /* record was truncated to fit */ + #define PERF_FLAG_FD_NO_GROUP (1UL << 0) #define PERF_FLAG_FD_OUTPUT (1UL << 1) #define PERF_FLAG_PID_CGROUP (1UL << 2) /* pid=cgroup id, per-cpu mode only */ diff --git a/kernel/events/core.c b/kernel/events/core.c index 6d9fdaef7b57..dbc2eff32230 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -5916,6 +5916,40 @@ void perf_event_mmap(struct vm_area_struct *vma) perf_event_mmap_event(&mmap_event); } +void perf_event_aux_event(struct perf_event *event, unsigned long head, + unsigned long size, u64 flags) +{ + struct perf_output_handle handle; + struct perf_sample_data sample; + struct perf_aux_event { + struct perf_event_header header; + u64 offset; + u64 size; + u64 flags; + } rec = { + .header = { + .type = PERF_RECORD_AUX, + .misc = 0, + .size = sizeof(rec), + }, + .offset = head, + .size = size, + .flags = flags, + }; + int ret; + + perf_event_header__init_id(&rec.header, &sample, event); + ret = perf_output_begin(&handle, event, rec.header.size); + + if (ret) + return; + + perf_output_put(&handle, rec); + perf_event__output_id_sample(event, &handle, &sample); + + perf_output_end(&handle); +} + /* * IRQ throttle logging */ diff --git a/kernel/events/internal.h b/kernel/events/internal.h index 0f6d08015927..4d117a981431 100644 --- a/kernel/events/internal.h +++ b/kernel/events/internal.h @@ -62,6 +62,9 @@ static inline bool rb_has_aux(struct ring_buffer *rb) return !!rb->aux_nr_pages; } +void perf_event_aux_event(struct perf_event *event, unsigned long head, + unsigned long size, u64 flags); + extern void perf_event_header__init_id(struct perf_event_header *header, struct perf_sample_data *data, -- 2.20.1