From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-io1-f74.google.com (mail-io1-f74.google.com [209.85.166.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6D251216A0F for ; Thu, 7 Nov 2024 19:04:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.74 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731006266; cv=none; b=Mf1bZXvHXSesGg67sgimaXzNUH58pPL7Ib5nQju4LWsX1XtazDveiFhVLats+LMqYPyQj69f6DQX5kYcr+vWPenun8ay0hK9aMj+7AVP/SC7WpA12hrtEEfN7GGCGSbH5/7OHDZ2GdWsduv//pg2wzGT7jWWnmd81ZHkT2wZ5G0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731006266; c=relaxed/simple; bh=rH+0U/U8QuJjNW02LPfeGGz9R6pA7ntPpm1SvusvDpE=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=uYvIjDT/eX2EdLGZRWq0SrAoCLPVhoqqQzTysjDIbhHgLUB7j45f9DA7M66xZWmlDTrM978zulkcAdozndoUORRXm8MzBhsOWprHqK3bC2VhDmdimU7bZsA20hvbqTYiIVsd2WgJgibOx3KoT9On44e0K5GtdTEtIfXKNJwXv6M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--coltonlewis.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=c/RRTibV; arc=none smtp.client-ip=209.85.166.74 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--coltonlewis.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="c/RRTibV" Received: by mail-io1-f74.google.com with SMTP id ca18e2360f4ac-83ac3fe1cf4so142290839f.3 for ; Thu, 07 Nov 2024 11:04:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1731006263; x=1731611063; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=307d+oKSDEQceCQxX9m+tC9eleFe8W0Ggi8DlXu2swQ=; b=c/RRTibVQaVzNzQrAwxE4Znu7PlIxLgW1UVR7YLRCpWehSWa6liJuGhKi9e7fGoaQJ D5hv8C4gr3mp7Xr0W26VyViOr4AfaPJXAV6DhYDXFBVEaEhmhyTIJqwzDlwTyhdXWb2Q QE7BI/oHeY97MhqpyGk2/0nDGNW/X9UZsZ8xNW4Dg0ZgwQzWcHkqmKMFt6bgvMuDmV1N vhnQNTwOMEsy1Eyppv6VIpmqYq9g4QSKPWpMrQc+6pWrhSO5gZNzIjpnyoc6JTOJ2NOq eAOXRjUeXJIqxna1lKP0zzYYZX1i/Ayli+9DriOFLkkPlhOKXZuemA4DFP3VH8Z83kHy hm/A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1731006263; x=1731611063; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=307d+oKSDEQceCQxX9m+tC9eleFe8W0Ggi8DlXu2swQ=; b=aJEQjKAVvfFmbch19NkmoJLqwGfUomc287dsu6LvQI/TNsevXh+7b2H8FjibGxTaXi mobh8Qq3KVVByCGAUobSquPdMZ4Rd1pPHl5WY9m/eaqMPZq7QDmYLTftbQAD83EQDBcn FfCsGPlN41c/PHmuH7bwy1WxIve8P1wISVpLq1v/rGGHwUK+89ZG4THKQnsItYv9uDmH ooaF/0JJj/0Ql5SLPwDxI6eRFQUvyylwrLWxViTibKXTtg7BJBDvISyJdxZtuobAS8oj /H2mM+f1Wu7u+uW/lkjUR1Bz1gpi+aN+RmWAe5juBxYb1ZTFidP6aNBKQtfYjXqT7OLp +O5w== X-Forwarded-Encrypted: i=1; AJvYcCXD/Bb/LCNbdCno6mjNkXJpg/pTM+JoajUsziaDH0FGplzpCSKPkiWvQl3df67uUqgMK5VhYw6Mo1+F3jRmT5N5@vger.kernel.org X-Gm-Message-State: AOJu0YwiV9MTOOW48QPtVybjwoiWssS4EiVfEqXUBrUK2zv76dlOAGsc RX1h8O2r2O6feieo0xdVSgKYk8vtnk6DRl3Nxcnk7dJ9Ip/BGFRe4eMR6bmeZyG3u6JTuAaBOxS UvImU00+sgcsAUUDxE2Hrkg== X-Google-Smtp-Source: AGHT+IEEjTpPYQzMBAhybW04MdjW8AF86rC0c7OtK7AUjaSX9oKv312D06txGG3KDB2dLThYbB5SuJMvIMPM40vk7Q== X-Received: from coltonlewis-kvm.c.googlers.com ([fda3:e722:ac3:cc00:11b:3898:ac11:fa18]) (user=coltonlewis job=sendgmr) by 2002:a05:6e02:1d88:b0:3a6:be9e:fb56 with SMTP id e9e14a558f8ab-3a6f1a44701mr21665ab.3.1731006263567; Thu, 07 Nov 2024 11:04:23 -0800 (PST) Date: Thu, 7 Nov 2024 19:03:31 +0000 Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.47.0.277.g8800431eea-goog Message-ID: <20241107190336.2963882-1-coltonlewis@google.com> Subject: [PATCH v7 0/5] Correct perf sampling with Guest VMs From: Colton Lewis To: kvm@vger.kernel.org Cc: Oliver Upton , Sean Christopherson , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , Kan Liang , Will Deacon , Russell King , Catalin Marinas , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Naveen N Rao , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Thomas Gleixner , Borislav Petkov , Dave Hansen , x86@kernel.org, "H . Peter Anvin" , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, Colton Lewis Content-Type: text/plain; charset="UTF-8" v7: * Refactor th misc_flags check in patch 4 and 5 for more clarity v6: https://lore.kernel.org/all/20241105195603.2317483-1-coltonlewis@google.com/ v5: https://lore.kernel.org/all/20240920174740.781614-1-coltonlewis@google.com/ v4: https://lore.kernel.org/kvm/20240919190750.4163977-1-coltonlewis@google.com/ v3: https://lore.kernel.org/kvm/20240912205133.4171576-1-coltonlewis@google.com/ v2: https://lore.kernel.org/kvm/20240911222433.3415301-1-coltonlewis@google.com/ v1: https://lore.kernel.org/kvm/20240904204133.1442132-1-coltonlewis@google.com/ This series cleans up perf recording around guest events and improves the accuracy of the resulting perf reports. Perf was incorrectly counting any PMU overflow interrupt that occurred while a VCPU was loaded as a guest event even when the events were not truely guest events. This lead to much less accurate and useful perf recordings. See as an example the below reports of `perf record dirty_log_perf_test -m 2 -v 4` before and after the series on ARM64. Without series: Samples: 15K of event 'instructions', Event count (approx.): 31830580924 Overhead Command Shared Object Symbol 54.54% dirty_log_perf_ dirty_log_perf_test [.] run_test 5.39% dirty_log_perf_ dirty_log_perf_test [.] vcpu_worker 0.89% dirty_log_perf_ [kernel.vmlinux] [k] release_pages 0.70% dirty_log_perf_ [kernel.vmlinux] [k] free_pcppages_bulk 0.62% dirty_log_perf_ dirty_log_perf_test [.] userspace_mem_region_find 0.49% dirty_log_perf_ dirty_log_perf_test [.] sparsebit_is_set 0.46% dirty_log_perf_ dirty_log_perf_test [.] _virt_pg_map 0.46% dirty_log_perf_ dirty_log_perf_test [.] node_add 0.37% dirty_log_perf_ dirty_log_perf_test [.] node_reduce 0.35% dirty_log_perf_ [kernel.vmlinux] [k] free_unref_page_commit 0.33% dirty_log_perf_ [kernel.vmlinux] [k] __kvm_pgtable_walk 0.31% dirty_log_perf_ [kernel.vmlinux] [k] stage2_attr_walker 0.29% dirty_log_perf_ [kernel.vmlinux] [k] unmap_page_range 0.29% dirty_log_perf_ dirty_log_perf_test [.] test_assert 0.26% dirty_log_perf_ [kernel.vmlinux] [k] __mod_memcg_lruvec_state 0.24% dirty_log_perf_ [kernel.vmlinux] [k] kvm_s2_put_page With series: Samples: 15K of event 'instructions', Event count (approx.): 31830580924 Samples: 15K of event 'instructions', Event count (approx.): 30898031385 Overhead Command Shared Object Symbol 54.05% dirty_log_perf_ dirty_log_perf_test [.] run_test 5.48% dirty_log_perf_ [kernel.kallsyms] [k] kvm_arch_vcpu_ioctl_run 4.70% dirty_log_perf_ dirty_log_perf_test [.] vcpu_worker 3.11% dirty_log_perf_ [kernel.kallsyms] [k] kvm_handle_guest_abort 2.24% dirty_log_perf_ [kernel.kallsyms] [k] up_read 1.98% dirty_log_perf_ [kernel.kallsyms] [k] __kvm_tlb_flush_vmid_ipa_nsh 1.97% dirty_log_perf_ [kernel.kallsyms] [k] __pi_clear_page 1.30% dirty_log_perf_ [kernel.kallsyms] [k] down_read 1.13% dirty_log_perf_ [kernel.kallsyms] [k] release_pages 1.12% dirty_log_perf_ [kernel.kallsyms] [k] __kvm_pgtable_walk 1.08% dirty_log_perf_ [kernel.kallsyms] [k] folio_batch_move_lru 1.06% dirty_log_perf_ [kernel.kallsyms] [k] __srcu_read_lock 1.03% dirty_log_perf_ [kernel.kallsyms] [k] get_page_from_freelist 1.01% dirty_log_perf_ [kernel.kallsyms] [k] __pte_offset_map_lock 0.82% dirty_log_perf_ [kernel.kallsyms] [k] handle_mm_fault 0.74% dirty_log_perf_ [kernel.kallsyms] [k] mas_state_walk Colton Lewis (5): arm: perf: Drop unused functions perf: Hoist perf_instruction_pointer() and perf_misc_flags() powerpc: perf: Use perf_arch_instruction_pointer() x86: perf: Refactor misc flag assignments perf: Correct perf sampling with guest VMs arch/arm/include/asm/perf_event.h | 7 --- arch/arm/kernel/perf_callchain.c | 17 ------- arch/arm64/include/asm/perf_event.h | 4 -- arch/arm64/kernel/perf_callchain.c | 28 ------------ arch/powerpc/include/asm/perf_event_server.h | 6 +-- arch/powerpc/perf/callchain.c | 2 +- arch/powerpc/perf/callchain_32.c | 2 +- arch/powerpc/perf/callchain_64.c | 2 +- arch/powerpc/perf/core-book3s.c | 4 +- arch/s390/include/asm/perf_event.h | 6 +-- arch/s390/kernel/perf_event.c | 4 +- arch/x86/events/core.c | 48 ++++++++++++-------- arch/x86/include/asm/perf_event.h | 12 +++-- include/linux/perf_event.h | 26 +++++++++-- kernel/events/core.c | 27 ++++++++++- 15 files changed, 96 insertions(+), 99 deletions(-) base-commit: 59b723cd2adbac2a34fc8e12c74ae26ae45bf230 -- 2.47.0.277.g8800431eea-goog