From nobody Fri Dec 19 04:07:51 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 65F63CDB46E for ; Thu, 12 Oct 2023 06:25:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377673AbjJLGZL (ORCPT ); Thu, 12 Oct 2023 02:25:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54252 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1377791AbjJLGYu (ORCPT ); Thu, 12 Oct 2023 02:24:50 -0400 Received: from mail-yw1-x1149.google.com (mail-yw1-x1149.google.com [IPv6:2607:f8b0:4864:20::1149]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A52E21B2 for ; Wed, 11 Oct 2023 23:24:33 -0700 (PDT) Received: by mail-yw1-x1149.google.com with SMTP id 00721157ae682-59f61a639b9so9879167b3.1 for ; Wed, 11 Oct 2023 23:24:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1697091872; x=1697696672; darn=vger.kernel.org; h=to:from:subject:references:mime-version:message-id:in-reply-to:date :from:to:cc:subject:date:message-id:reply-to; bh=flxfAGeU36X3VCWvCeBnyhGj7NRxqRtkjKz9SEhq+zk=; b=Qp8RZwl6K+UKiZuC0kkyEe1H4Dhxz1Q8ofiKc7xh4psBeYZL5MAAFeNeyu00AXzr/H O86dFjRmhv86edW3lyAfIsA9fl7OkdB1dnKHoz12KrDJLt2TleEL1pB/rXW1KOVKrAws QUQG9pxv3eMH4wAwZwB8XoZGCPnUy835T/KsTHrvMJ+MfsfqnG3Qi0l3mUVnSOdVPk9S Hlrcs+dWL0uLJ4yAIbfMe42o724+HWKx0CtsN2ikMCdRxgPwuV2VK1lSSTqs2EQr26vB 9rBsoUZMAU/LdWtF0ZEPytcQNBKNTNwGlfc02UEBxuC0aiKcOLokSj9IhegbCuHykG7v uiLg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697091872; x=1697696672; h=to:from:subject:references:mime-version:message-id:in-reply-to:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=flxfAGeU36X3VCWvCeBnyhGj7NRxqRtkjKz9SEhq+zk=; b=r2moRX0id43FbjjIYuz8I9mP3vXV+Sgv6zWNa2lXXw39z6S1QjjMZ+bi2eUUJTOAkn BADX6EaYBGlFIxghJF+pxYE2S8gCyKJ4uz2pKjNp1ZOyv3/Yhq8D0etiBKWbWkSXKs8O 4VyrwvpDsGk/u7MEhs+adZKcgehYPwwfK7h8wK2hI6V7zZJdj7O29RDp43pmTNoxAopC f4slKMlI6VTQ9wM9QI0nBgJsXjObOURwlNP4gObO89o+G7d/tpKoN3A8d84cL+7bkvQo UM7tRPSlThy6EpmidDBmZlL6psdUDpD84qtEB6cd8REbemTdNieSBduTmQR2ZCiS621K Jxgg== X-Gm-Message-State: AOJu0YxXjAqNU2RGjw0G5dbIxesvOg2ESYHREn3gEPa5rXdkn7MIiKsp trztqyXBQPyprSAK+to3dPjyMk/1VovT X-Google-Smtp-Source: AGHT+IGdUdinYuEq8T3uAohDpFLB8P8wmRDQ5QHEXJxvYYgkout89ScuOm/SWzNEJeVgK30fxeyLC6iN4e5k X-Received: from irogers.svl.corp.google.com ([2620:15c:2a3:200:7be5:14d2:880b:c5c9]) (user=irogers job=sendgmr) by 2002:a81:a909:0:b0:59b:e97e:f7e3 with SMTP id g9-20020a81a909000000b0059be97ef7e3mr422912ywh.2.1697091872656; Wed, 11 Oct 2023 23:24:32 -0700 (PDT) Date: Wed, 11 Oct 2023 23:23:57 -0700 In-Reply-To: <20231012062359.1616786-1-irogers@google.com> Message-Id: <20231012062359.1616786-12-irogers@google.com> Mime-Version: 1.0 References: <20231012062359.1616786-1-irogers@google.com> X-Mailer: git-send-email 2.42.0.609.gbb76f46606-goog Subject: [PATCH v2 11/13] libperf: Lazily allocate mmap event copy From: Ian Rogers To: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Ian Rogers , Adrian Hunter , Nick Terrell , Kan Liang , Song Liu , Sandipan Das , Anshuman Khandual , James Clark , Liam Howlett , Miguel Ojeda , Leo Yan , German Gomez , Ravi Bangoria , Artem Savkov , Athira Rajeev , Andi Kleen , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, bpf@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The event copy in the mmap is used to have storage to a read event. Not all users of mmaps read the events, such as perf record, so switch the allocation to being on first read rather than being embedded within the perf_mmap. Signed-off-by: Ian Rogers --- tools/lib/perf/include/internal/mmap.h | 2 +- tools/lib/perf/mmap.c | 9 +++++++++ 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/tools/lib/perf/include/internal/mmap.h b/tools/lib/perf/includ= e/internal/mmap.h index 5a062af8e9d8..b11aaf5ed645 100644 --- a/tools/lib/perf/include/internal/mmap.h +++ b/tools/lib/perf/include/internal/mmap.h @@ -33,7 +33,7 @@ struct perf_mmap { bool overwrite; u64 flush; libperf_unmap_cb_t unmap_cb; - char event_copy[PERF_SAMPLE_MAX_SIZE] __aligned(8); + void *event_copy; struct perf_mmap *next; }; =20 diff --git a/tools/lib/perf/mmap.c b/tools/lib/perf/mmap.c index 2184814b37dd..91ae46aac378 100644 --- a/tools/lib/perf/mmap.c +++ b/tools/lib/perf/mmap.c @@ -51,6 +51,8 @@ int perf_mmap__mmap(struct perf_mmap *map, struct perf_mm= ap_param *mp, =20 void perf_mmap__munmap(struct perf_mmap *map) { + free(map->event_copy); + map->event_copy =3D NULL; if (map && map->base !=3D NULL) { munmap(map->base, perf_mmap__mmap_len(map)); map->base =3D NULL; @@ -226,6 +228,13 @@ static union perf_event *perf_mmap__read(struct perf_m= map *map, unsigned int len =3D min(sizeof(*event), size), cpy; void *dst =3D map->event_copy; =20 + if (!dst) { + dst =3D malloc(PERF_SAMPLE_MAX_SIZE); + if (!dst) + return NULL; + map->event_copy =3D dst; + } + do { cpy =3D min(map->mask + 1 - (offset & map->mask), len); memcpy(dst, &data[offset & map->mask], cpy); --=20 2.42.0.609.gbb76f46606-goog