From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793941989; b=p/Rsk3h2+n9CgB9ZBJN3x+FaDByH8USYqUgwUT7C2jvq2wLyjkcHnEwEra/UuwcxDp9a gFHWN0CYxHPD3hnqiWAXYA1D7pdAhIIrOByRDRDjdalvPan+p8jvwUkO3Ipwc/UKMBc7k 9CfJv6XfsE7tToMNTp1AnkLPx4J1UFemKLq2+oPYXuGFwrH9Rs0czIMPRDo96DIcoJj00 Cu+HWxfCq8qFl1ImtTFIg01fmkZrTQK/9Rg+1IktdKq3ndf/FKPgeSBtXImn2YUFsRTOr HYO6Lvu/2LUuhMrgZntb7eFBceq3qtacVI9LGMG0PFr60G10z+sf8AP2u7+6Lkl5WTw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793941989; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=80f9Z6larh29cFZKrHb5jNIpBmK0kVVoSTJqe/49Nyk=; b=Bhr8/ACkzocn+JxQORldZbMsczjuS+pwTLIgJktpv3Ec6S1wKE614fkXTqeWwKEzRgGH aOdgqY2M1Dx7mh87pcrOmrJEbWef35v5ouXZvs2NUyQf/GSt0ARNCZgTv1skFXVPv3a1z rAs37hMFSxFw/SPbsW32w2TEVNz6oOH1Pl+TyzrG9fdcuZu8YWIJir1GiD2ogXplQD4kd 7dyUjTbcIE19FRVkxFQNr5JWxNTB9t8nntj3yZkm1eHyP6YxHlNHTwVZyo73xsO7GweRK 2BflhlOocrzBNx7ODfTQHfk9YUi3W2YON9CMT1PU6r5S6hbcYljnULyJEUSCOdpiV0A== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=lZsq1ilI; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 811C6606A326 for ; Fri, 6 Nov 2026 05:13:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=lZsq1ilI Received: by smtp.kernel.org (Postfix) with ESMTPSA id 42DFE1F008A1; Fri, 6 Nov 2026 05:13:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793941989; bh=80f9Z6larh29cFZKrHb5jNIpBmK0kVVoSTJqe/49Nyk=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=lZsq1ilI1X+jA4Ha47DMznEs0zNZ78ElhLoQAu1waxBupVkJAM8plveUIHSCS4WWz ZQexA7GR2QGbo2x8a8nIkiWalTMSRNZX+k2FRlbp3ceKD2NYiqsE7RqW7j1Lp4kbLP 05OE4AHbunI0O1Ol2T2JFRPX/OK6GfHh4hzxvOwlldqRcK3zFbRp6mTlMO+aAz2FEv kq35vnoAb4Qujd67aMjoT0F8dqgVgm3qHXVhUmiJxQH6wcG8t6kdvSHQpeLK2utChV e0HZ96LudWs6FkP1rYPXeNO7j4j5KVyBwVeaOsbymzNVLL6xwXrPoBzzU9PKkqp8Rp R4VA0/OM9sR7g== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v7 11/14] alpha/perf: report the data source of ProfileMe memory accesses Reply-To: sashiko-reviews@lists.linux.dev To: "Matt Turner" Cc: linux-perf-users@vger.kernel.org In-Reply-To: <20261105-alpha-profileme-v7-11-c474e892abb0@gmail.com> References: <20261105-alpha-profileme-v7-0-c474e892abb0@gmail.com> <20261105-alpha-profileme-v7-11-c474e892abb0@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Fri, 06 Nov 2026 05:13:08 +0000 X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > Whether a ProfileMe sample's memory access missed the DTB is only in the > PERF_SAMPLE_RAW data, as a DTB miss trap. >=20 > Set PERF_SAMPLE_DATA_SRC for the samples of memory instructions, so that > the memory sort keys see them. One that trapped on a DTB miss gets an L1 > miss in mem_dtlb. PALcode fills the DTB, so one that retired without > that trap hit it, and gets an L1 hit. mem_op comes from the opcode, as > I_STAT does not say whether the access was a load or a store. A load > into $31 or $f31 is a prefetch, except for ldq_u, a UNOP that is left > out. Samples that fall back to the interrupted PC get none. >=20 > On an EV7, a loop that loads one word from each page of 64 MB in random > order had as many DTB hit samples on the load as misses: the miss trap > aborts the load, and its refetch hits. A prefetch into $31 takes the > same trap, and its samples are reported as PFETCH misses and hits. >=20 > I_STAT[TRP] is ignored for an instruction killed before it was mapped. On > an EV7, TRP and MIS were seen set for killed instructions that are not > even branches. >=20 > Suggested-by: Ian Rogers > Assisted-by: Claude:claude-opus-5-5 > Reviewed-by: Magnus Lindholm > Tested-by: Magnus Lindholm > Signed-off-by: Matt Turner Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261105-alpha-prof= ileme-v7-0-c474e892abb0@gmail.com?part=3D11