From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 232E6C47404 for ; Fri, 11 Oct 2019 20:10:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CBCED21D56 for ; Fri, 11 Oct 2019 20:10:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570824654; bh=vWnCe071XdxnNLguiwf+nDRvML3LseWdhPOXo+KHszc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=EPt30W/WB9EX4QTgugLegf4ipeFD3bd1RtBfkr87p1Fg2sChWPvjbWd+fI6hZUzNQ pCaTaVlqpoTLoqGZytomySp5PC2uHqjvK0WJvvDm9V5UpDCzqp6fMWdIW+KrCBsll7 ZEcSdzGKxhPUeNclofPvJJT/gNJgDmxviwHFnXV8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729289AbfJKUKw (ORCPT ); Fri, 11 Oct 2019 16:10:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:46710 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729316AbfJKUKu (ORCPT ); Fri, 11 Oct 2019 16:10:50 -0400 Received: from quaco.ghostprotocols.net (189-94-137-67.3g.claro.net.br [189.94.137.67]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E214F2196E; Fri, 11 Oct 2019 20:10:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570824648; bh=vWnCe071XdxnNLguiwf+nDRvML3LseWdhPOXo+KHszc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nXZHrMZ0D8YMUdCWvJHFZTZMK72CekiKnLdboSXF6ElWcyBepR37/4lcQG1+7Zl5z KWLoffvyX3uAGgavekJLQETRZleCx2VGpzAseS3DOmO5oYgzOixy+quVmtKAm/Ho40 pxcVjekN8U3jmJ8IjTrtWtGGQQyB1HHyvzoFU6BM= From: Arnaldo Carvalho de Melo To: Ingo Molnar , Thomas Gleixner Cc: Jiri Olsa , Namhyung Kim , Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Alexander Shishkin , Michael Petlan , Peter Zijlstra , Arnaldo Carvalho de Melo Subject: [PATCH 51/69] libperf: Adopt perf_mmap__read_init() from tools/perf Date: Fri, 11 Oct 2019 17:05:41 -0300 Message-Id: <20191011200559.7156-52-acme@kernel.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20191011200559.7156-1-acme@kernel.org> References: <20191011200559.7156-1-acme@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jiri Olsa Move perf_mmap__read_init() from tools/perf to libperf and export it in perf/mmap.h header. And add pr_debug2()/pr_debug3() macros support, because the code is using them. Signed-off-by: Jiri Olsa Cc: Alexander Shishkin Cc: Michael Petlan Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20191007125344.14268-11-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/arch/x86/tests/perf-time-to-tsc.c | 2 +- tools/perf/builtin-kvm.c | 2 +- tools/perf/builtin-top.c | 2 +- tools/perf/builtin-trace.c | 2 +- tools/perf/lib/include/perf/core.h | 2 + tools/perf/lib/include/perf/mmap.h | 1 + tools/perf/lib/internal.h | 2 + tools/perf/lib/libperf.map | 1 + tools/perf/lib/mmap.c | 84 ++++++++++++++++++++ tools/perf/tests/backward-ring-buffer.c | 2 +- tools/perf/tests/bpf.c | 2 +- tools/perf/tests/code-reading.c | 2 +- tools/perf/tests/keep-tracking.c | 2 +- tools/perf/tests/mmap-basic.c | 2 +- tools/perf/tests/openat-syscall-tp-fields.c | 2 +- tools/perf/tests/perf-record.c | 2 +- tools/perf/tests/sw-clock.c | 2 +- tools/perf/tests/switch-tracking.c | 2 +- tools/perf/tests/task-exit.c | 2 +- tools/perf/util/evlist.c | 2 +- tools/perf/util/mmap.c | 82 +------------------ tools/perf/util/mmap.h | 1 - tools/perf/util/python.c | 2 +- 23 files changed, 107 insertions(+), 98 deletions(-) diff --git a/tools/perf/arch/x86/tests/perf-time-to-tsc.c b/tools/perf/arch/x86/tests/perf-time-to-tsc.c index 3397898824f6..6a0c3ff78e01 100644 --- a/tools/perf/arch/x86/tests/perf-time-to-tsc.c +++ b/tools/perf/arch/x86/tests/perf-time-to-tsc.c @@ -118,7 +118,7 @@ int test__perf_time_to_tsc(struct test *test __maybe_unused, int subtest __maybe for (i = 0; i < evlist->core.nr_mmaps; i++) { md = &evlist->mmap[i]; - if (perf_mmap__read_init(md) < 0) + if (perf_mmap__read_init(&md->core) < 0) continue; while ((event = perf_mmap__read_event(md)) != NULL) { diff --git a/tools/perf/builtin-kvm.c b/tools/perf/builtin-kvm.c index 0c04c4c6c1eb..b6a8078dd446 100644 --- a/tools/perf/builtin-kvm.c +++ b/tools/perf/builtin-kvm.c @@ -760,7 +760,7 @@ static s64 perf_kvm__mmap_read_idx(struct perf_kvm_stat *kvm, int idx, *mmap_time = ULLONG_MAX; md = &evlist->mmap[idx]; - err = perf_mmap__read_init(md); + err = perf_mmap__read_init(&md->core); if (err < 0) return (err == -EAGAIN) ? 0 : -1; diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c index 5fcf15799415..4a4bb7b20c39 100644 --- a/tools/perf/builtin-top.c +++ b/tools/perf/builtin-top.c @@ -870,7 +870,7 @@ static void perf_top__mmap_read_idx(struct perf_top *top, int idx) union perf_event *event; md = opts->overwrite ? &evlist->overwrite_mmap[idx] : &evlist->mmap[idx]; - if (perf_mmap__read_init(md) < 0) + if (perf_mmap__read_init(&md->core) < 0) return; while ((event = perf_mmap__read_event(md)) != NULL) { diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index 6a5708438566..cd69d68e7f1d 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -3801,7 +3801,7 @@ static int trace__run(struct trace *trace, int argc, const char **argv) struct mmap *md; md = &evlist->mmap[i]; - if (perf_mmap__read_init(md) < 0) + if (perf_mmap__read_init(&md->core) < 0) continue; while ((event = perf_mmap__read_event(md)) != NULL) { diff --git a/tools/perf/lib/include/perf/core.h b/tools/perf/lib/include/perf/core.h index cfd70e720c1c..2a80e4b6f819 100644 --- a/tools/perf/lib/include/perf/core.h +++ b/tools/perf/lib/include/perf/core.h @@ -12,6 +12,8 @@ enum libperf_print_level { LIBPERF_WARN, LIBPERF_INFO, LIBPERF_DEBUG, + LIBPERF_DEBUG2, + LIBPERF_DEBUG3, }; typedef int (*libperf_print_fn_t)(enum libperf_print_level level, diff --git a/tools/perf/lib/include/perf/mmap.h b/tools/perf/lib/include/perf/mmap.h index d3678d1834d9..646e9052b003 100644 --- a/tools/perf/lib/include/perf/mmap.h +++ b/tools/perf/lib/include/perf/mmap.h @@ -7,5 +7,6 @@ struct perf_mmap; LIBPERF_API void perf_mmap__consume(struct perf_mmap *map); +LIBPERF_API int perf_mmap__read_init(struct perf_mmap *map); #endif /* __LIBPERF_MMAP_H */ diff --git a/tools/perf/lib/internal.h b/tools/perf/lib/internal.h index dc92f241732e..37db745e1502 100644 --- a/tools/perf/lib/internal.h +++ b/tools/perf/lib/internal.h @@ -14,5 +14,7 @@ do { \ #define pr_warning(fmt, ...) __pr(LIBPERF_WARN, fmt, ##__VA_ARGS__) #define pr_info(fmt, ...) __pr(LIBPERF_INFO, fmt, ##__VA_ARGS__) #define pr_debug(fmt, ...) __pr(LIBPERF_DEBUG, fmt, ##__VA_ARGS__) +#define pr_debug2(fmt, ...) __pr(LIBPERF_DEBUG2, fmt, ##__VA_ARGS__) +#define pr_debug3(fmt, ...) __pr(LIBPERF_DEBUG3, fmt, ##__VA_ARGS__) #endif /* __LIBPERF_INTERNAL_H */ diff --git a/tools/perf/lib/libperf.map b/tools/perf/lib/libperf.map index d7b327f224e2..bc3fbb213a3e 100644 --- a/tools/perf/lib/libperf.map +++ b/tools/perf/lib/libperf.map @@ -41,6 +41,7 @@ LIBPERF_0.0.1 { perf_evlist__set_maps; perf_evlist__poll; perf_mmap__consume; + perf_mmap__read_init; local: *; }; diff --git a/tools/perf/lib/mmap.c b/tools/perf/lib/mmap.c index 4cada1c89fdb..fdbc6c550dea 100644 --- a/tools/perf/lib/mmap.c +++ b/tools/perf/lib/mmap.c @@ -1,11 +1,15 @@ // SPDX-License-Identifier: GPL-2.0 #include +#include +#include +#include #include #include #include #include #include #include +#include "internal.h" void perf_mmap__init(struct perf_mmap *map, bool overwrite, libperf_unmap_cb_t unmap_cb) @@ -91,3 +95,83 @@ void perf_mmap__consume(struct perf_mmap *map) if (refcount_read(&map->refcnt) == 1 && perf_mmap__empty(map)) perf_mmap__put(map); } + +static int overwrite_rb_find_range(void *buf, int mask, u64 *start, u64 *end) +{ + struct perf_event_header *pheader; + u64 evt_head = *start; + int size = mask + 1; + + pr_debug2("%s: buf=%p, start=%"PRIx64"\n", __func__, buf, *start); + pheader = (struct perf_event_header *)(buf + (*start & mask)); + while (true) { + if (evt_head - *start >= (unsigned int)size) { + pr_debug("Finished reading overwrite ring buffer: rewind\n"); + if (evt_head - *start > (unsigned int)size) + evt_head -= pheader->size; + *end = evt_head; + return 0; + } + + pheader = (struct perf_event_header *)(buf + (evt_head & mask)); + + if (pheader->size == 0) { + pr_debug("Finished reading overwrite ring buffer: get start\n"); + *end = evt_head; + return 0; + } + + evt_head += pheader->size; + pr_debug3("move evt_head: %"PRIx64"\n", evt_head); + } + WARN_ONCE(1, "Shouldn't get here\n"); + return -1; +} + +/* + * Report the start and end of the available data in ringbuffer + */ +static int __perf_mmap__read_init(struct perf_mmap *md) +{ + u64 head = perf_mmap__read_head(md); + u64 old = md->prev; + unsigned char *data = md->base + page_size; + unsigned long size; + + md->start = md->overwrite ? head : old; + md->end = md->overwrite ? old : head; + + if ((md->end - md->start) < md->flush) + return -EAGAIN; + + size = md->end - md->start; + if (size > (unsigned long)(md->mask) + 1) { + if (!md->overwrite) { + WARN_ONCE(1, "failed to keep up with mmap data. (warn only once)\n"); + + md->prev = head; + perf_mmap__consume(md); + return -EAGAIN; + } + + /* + * Backward ring buffer is full. We still have a chance to read + * most of data from it. + */ + if (overwrite_rb_find_range(data, md->mask, &md->start, &md->end)) + return -EINVAL; + } + + return 0; +} + +int perf_mmap__read_init(struct perf_mmap *map) +{ + /* + * Check if event was unmapped due to a POLLHUP/POLLERR. + */ + if (!refcount_read(&map->refcnt)) + return -ENOENT; + + return __perf_mmap__read_init(map); +} diff --git a/tools/perf/tests/backward-ring-buffer.c b/tools/perf/tests/backward-ring-buffer.c index 13f9a060361a..ff3a986983ab 100644 --- a/tools/perf/tests/backward-ring-buffer.c +++ b/tools/perf/tests/backward-ring-buffer.c @@ -38,7 +38,7 @@ static int count_samples(struct evlist *evlist, int *sample_count, struct mmap *map = &evlist->overwrite_mmap[i]; union perf_event *event; - perf_mmap__read_init(map); + perf_mmap__read_init(&map->core); while ((event = perf_mmap__read_event(map)) != NULL) { const u32 type = event->header.type; diff --git a/tools/perf/tests/bpf.c b/tools/perf/tests/bpf.c index 6f0d239f8277..73d26c63d624 100644 --- a/tools/perf/tests/bpf.c +++ b/tools/perf/tests/bpf.c @@ -185,7 +185,7 @@ static int do_test(struct bpf_object *obj, int (*func)(void), struct mmap *md; md = &evlist->mmap[i]; - if (perf_mmap__read_init(md) < 0) + if (perf_mmap__read_init(&md->core) < 0) continue; while ((event = perf_mmap__read_event(md)) != NULL) { diff --git a/tools/perf/tests/code-reading.c b/tools/perf/tests/code-reading.c index b5a57bb54c25..cf992e0b27ff 100644 --- a/tools/perf/tests/code-reading.c +++ b/tools/perf/tests/code-reading.c @@ -426,7 +426,7 @@ static int process_events(struct machine *machine, struct evlist *evlist, for (i = 0; i < evlist->core.nr_mmaps; i++) { md = &evlist->mmap[i]; - if (perf_mmap__read_init(md) < 0) + if (perf_mmap__read_init(&md->core) < 0) continue; while ((event = perf_mmap__read_event(md)) != NULL) { diff --git a/tools/perf/tests/keep-tracking.c b/tools/perf/tests/keep-tracking.c index 31c005e07b17..e85da7e77269 100644 --- a/tools/perf/tests/keep-tracking.c +++ b/tools/perf/tests/keep-tracking.c @@ -39,7 +39,7 @@ static int find_comm(struct evlist *evlist, const char *comm) found = 0; for (i = 0; i < evlist->core.nr_mmaps; i++) { md = &evlist->mmap[i]; - if (perf_mmap__read_init(md) < 0) + if (perf_mmap__read_init(&md->core) < 0) continue; while ((event = perf_mmap__read_event(md)) != NULL) { if (event->header.type == PERF_RECORD_COMM && diff --git a/tools/perf/tests/mmap-basic.c b/tools/perf/tests/mmap-basic.c index b176acc4f52e..77f42f0ac15d 100644 --- a/tools/perf/tests/mmap-basic.c +++ b/tools/perf/tests/mmap-basic.c @@ -114,7 +114,7 @@ int test__basic_mmap(struct test *test __maybe_unused, int subtest __maybe_unuse } md = &evlist->mmap[0]; - if (perf_mmap__read_init(md) < 0) + if (perf_mmap__read_init(&md->core) < 0) goto out_init; while ((event = perf_mmap__read_event(md)) != NULL) { diff --git a/tools/perf/tests/openat-syscall-tp-fields.c b/tools/perf/tests/openat-syscall-tp-fields.c index bbf8ba320721..d6a563120d93 100644 --- a/tools/perf/tests/openat-syscall-tp-fields.c +++ b/tools/perf/tests/openat-syscall-tp-fields.c @@ -93,7 +93,7 @@ int test__syscall_openat_tp_fields(struct test *test __maybe_unused, int subtest struct mmap *md; md = &evlist->mmap[i]; - if (perf_mmap__read_init(md) < 0) + if (perf_mmap__read_init(&md->core) < 0) continue; while ((event = perf_mmap__read_event(md)) != NULL) { diff --git a/tools/perf/tests/perf-record.c b/tools/perf/tests/perf-record.c index 6ebbcc65749e..2587cb8b2c0f 100644 --- a/tools/perf/tests/perf-record.c +++ b/tools/perf/tests/perf-record.c @@ -171,7 +171,7 @@ int test__PERF_RECORD(struct test *test __maybe_unused, int subtest __maybe_unus struct mmap *md; md = &evlist->mmap[i]; - if (perf_mmap__read_init(md) < 0) + if (perf_mmap__read_init(&md->core) < 0) continue; while ((event = perf_mmap__read_event(md)) != NULL) { diff --git a/tools/perf/tests/sw-clock.c b/tools/perf/tests/sw-clock.c index 1aeb558010c1..808669507c30 100644 --- a/tools/perf/tests/sw-clock.c +++ b/tools/perf/tests/sw-clock.c @@ -100,7 +100,7 @@ static int __test__sw_clock_freq(enum perf_sw_ids clock_id) evlist__disable(evlist); md = &evlist->mmap[0]; - if (perf_mmap__read_init(md) < 0) + if (perf_mmap__read_init(&md->core) < 0) goto out_init; while ((event = perf_mmap__read_event(md)) != NULL) { diff --git a/tools/perf/tests/switch-tracking.c b/tools/perf/tests/switch-tracking.c index 55728b3da057..bedfdec34972 100644 --- a/tools/perf/tests/switch-tracking.c +++ b/tools/perf/tests/switch-tracking.c @@ -270,7 +270,7 @@ static int process_events(struct evlist *evlist, for (i = 0; i < evlist->core.nr_mmaps; i++) { md = &evlist->mmap[i]; - if (perf_mmap__read_init(md) < 0) + if (perf_mmap__read_init(&md->core) < 0) continue; while ((event = perf_mmap__read_event(md)) != NULL) { diff --git a/tools/perf/tests/task-exit.c b/tools/perf/tests/task-exit.c index a0f689594848..035d42375d4b 100644 --- a/tools/perf/tests/task-exit.c +++ b/tools/perf/tests/task-exit.c @@ -118,7 +118,7 @@ int test__task_exit(struct test *test __maybe_unused, int subtest __maybe_unused retry: md = &evlist->mmap[0]; - if (perf_mmap__read_init(md) < 0) + if (perf_mmap__read_init(&md->core) < 0) goto out_init; while ((event = perf_mmap__read_event(md)) != NULL) { diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index 34ba47b9896b..d9a4a4b188ed 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -1809,7 +1809,7 @@ static void *perf_evlist__poll_thread(void *arg) struct mmap *map = &evlist->mmap[i]; union perf_event *event; - if (perf_mmap__read_init(map)) + if (perf_mmap__read_init(&map->core)) continue; while ((event = perf_mmap__read_event(map)) != NULL) { struct evsel *evsel = perf_evlist__event2evsel(evlist, event); diff --git a/tools/perf/util/mmap.c b/tools/perf/util/mmap.c index abe7cbe6c95f..59379118c2f1 100644 --- a/tools/perf/util/mmap.c +++ b/tools/perf/util/mmap.c @@ -365,86 +365,6 @@ int mmap__mmap(struct mmap *map, struct mmap_params *mp, int fd, int cpu) return perf_mmap__aio_mmap(map, mp); } -static int overwrite_rb_find_range(void *buf, int mask, u64 *start, u64 *end) -{ - struct perf_event_header *pheader; - u64 evt_head = *start; - int size = mask + 1; - - pr_debug2("%s: buf=%p, start=%"PRIx64"\n", __func__, buf, *start); - pheader = (struct perf_event_header *)(buf + (*start & mask)); - while (true) { - if (evt_head - *start >= (unsigned int)size) { - pr_debug("Finished reading overwrite ring buffer: rewind\n"); - if (evt_head - *start > (unsigned int)size) - evt_head -= pheader->size; - *end = evt_head; - return 0; - } - - pheader = (struct perf_event_header *)(buf + (evt_head & mask)); - - if (pheader->size == 0) { - pr_debug("Finished reading overwrite ring buffer: get start\n"); - *end = evt_head; - return 0; - } - - evt_head += pheader->size; - pr_debug3("move evt_head: %"PRIx64"\n", evt_head); - } - WARN_ONCE(1, "Shouldn't get here\n"); - return -1; -} - -/* - * Report the start and end of the available data in ringbuffer - */ -static int __perf_mmap__read_init(struct mmap *md) -{ - u64 head = perf_mmap__read_head(&md->core); - u64 old = md->core.prev; - unsigned char *data = md->core.base + page_size; - unsigned long size; - - md->core.start = md->core.overwrite ? head : old; - md->core.end = md->core.overwrite ? old : head; - - if ((md->core.end - md->core.start) < md->core.flush) - return -EAGAIN; - - size = md->core.end - md->core.start; - if (size > (unsigned long)(md->core.mask) + 1) { - if (!md->core.overwrite) { - WARN_ONCE(1, "failed to keep up with mmap data. (warn only once)\n"); - - md->core.prev = head; - perf_mmap__consume(&md->core); - return -EAGAIN; - } - - /* - * Backward ring buffer is full. We still have a chance to read - * most of data from it. - */ - if (overwrite_rb_find_range(data, md->core.mask, &md->core.start, &md->core.end)) - return -EINVAL; - } - - return 0; -} - -int perf_mmap__read_init(struct mmap *map) -{ - /* - * Check if event was unmapped due to a POLLHUP/POLLERR. - */ - if (!refcount_read(&map->core.refcnt)) - return -ENOENT; - - return __perf_mmap__read_init(map); -} - int perf_mmap__push(struct mmap *md, void *to, int push(struct mmap *map, void *to, void *buf, size_t size)) { @@ -454,7 +374,7 @@ int perf_mmap__push(struct mmap *md, void *to, void *buf; int rc = 0; - rc = perf_mmap__read_init(md); + rc = perf_mmap__read_init(&md->core); if (rc < 0) return (rc == -EAGAIN) ? 1 : -1; diff --git a/tools/perf/util/mmap.h b/tools/perf/util/mmap.h index 89fb93267ff1..6d818ef51f05 100644 --- a/tools/perf/util/mmap.h +++ b/tools/perf/util/mmap.h @@ -54,6 +54,5 @@ int perf_mmap__push(struct mmap *md, void *to, size_t mmap__mmap_len(struct mmap *map); -int perf_mmap__read_init(struct mmap *md); void perf_mmap__read_done(struct mmap *map); #endif /*__PERF_MMAP_H */ diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c index 82a4fa6c87bd..64eec2a239d4 100644 --- a/tools/perf/util/python.c +++ b/tools/perf/util/python.c @@ -1023,7 +1023,7 @@ static PyObject *pyrf_evlist__read_on_cpu(struct pyrf_evlist *pevlist, if (!md) return NULL; - if (perf_mmap__read_init(md) < 0) + if (perf_mmap__read_init(&md->core) < 0) goto end; event = perf_mmap__read_event(md); -- 2.21.0