From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 41DDC85924; Fri, 29 Mar 2024 16:37:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711730249; cv=none; b=mWOA/ufXFw4VcSrghw9sAEDqx/RzQqGAUGSld+VlHSe/6XfvGsdf9rfUzaXUfR6ylCMhvTd3TUA+NcBALpUUBgqPvJlS+30Bl3JZoYON2+7WdDxwSrTmovJyTofzCVC0GUFpWsJkvVePmSsxWn2eWr9XPy3jMpZ244EK15EhQgY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711730249; c=relaxed/simple; bh=fBciC2ZZHnRH3/kjSHMfkZjS+xXpE+eBjo2+9CEE158=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=rx5+y0IyQJXDC1/2MsPAAE0I02hIg2ZL8s1948/gRfO5HE/Kto+l5JLdLETVNd1f6j5lcT++DrsYh1i+MCWlhNsE0m0g41pcPkxMjkWW0IMY2nufMcgW8oymti8KTJh/0x/7+NTOw+YGz0FVYfPJwVlsq5BvkeGIO1V3OV1ihbI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bY27PDnV; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="bY27PDnV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9C00BC433C7; Fri, 29 Mar 2024 16:37:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711730248; bh=fBciC2ZZHnRH3/kjSHMfkZjS+xXpE+eBjo2+9CEE158=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bY27PDnVEvTCzggHxbB/fBn2xTSpQhK3YL+3hhX4dXUIp3z9SSMg9HiQH/QSXwYim BsdndruYori38l5mmXIU500nf9vylTo0FW74MnKEAGP2y7Vi/d6N12qA8ldEHRWU1q il2MAF6zTZOD84C49Ty3GvUQzNGiFSHhq+pqB7zUkAuMfDBEuoXI5eKNAqRZPyP7VX jRuFHDs5VkxmcChP5mrABx58dpp754BNN73+VDZqS/hy6orI/A1bgs7oaNghKD5l7f m8X6HL1z2bO8ZZIoMP5LB6sXSBGdzS9RXMfCuQQx77vW7o3allJCph6bchJ320X9D8 IznpOrsdN5XOw== From: Andrii Nakryiko To: x86@kernel.org, peterz@infradead.org, mingo@redhat.com, tglx@linutronix.de Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org, jolsa@kernel.org, song@kernel.org, kernel-team@meta.com, Andrii Nakryiko , Sandipan Das Subject: [PATCH v3 2/2] perf/x86/amd: don't reject sampling events with configured LBR Date: Fri, 29 Mar 2024 09:37:22 -0700 Message-ID: <20240329163722.2776730-2-andrii@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240329163722.2776730-1-andrii@kernel.org> References: <20240329163722.2776730-1-andrii@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Now that it's possible to capture LBR on AMD CPU from BPF at arbitrary point, there is no reason to artificially limit this feature to sampling events. So corresponding check is removed. AFAIU, there is no correctness implications of doing this (and it was possible to bypass this check by just setting perf_event's sample_period to 1 anyways, so it doesn't guard all that much). Reviewed-by: Sandipan Das Signed-off-by: Andrii Nakryiko --- arch/x86/events/amd/lbr.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/arch/x86/events/amd/lbr.c b/arch/x86/events/amd/lbr.c index 0e4de028590d..75920f895d67 100644 --- a/arch/x86/events/amd/lbr.c +++ b/arch/x86/events/amd/lbr.c @@ -310,10 +310,6 @@ int amd_pmu_lbr_hw_config(struct perf_event *event) { int ret = 0; - /* LBR is not recommended in counting mode */ - if (!is_sampling_event(event)) - return -EINVAL; - ret = amd_pmu_lbr_setup_filter(event); if (!ret) event->attach_state |= PERF_ATTACH_SCHED_CB; -- 2.43.0