From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 0344A55C336 for ; Tue, 13 Oct 2026 21:43:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791927821; cv=none; b=XCtQzh5I9Abz8VX+g4B88osJvAeMdNjzj8fi1YAML/jcdH6pEYHanV8wEOard499CuzGpT3FxF00Nb3jPligwNWhl9U+9spk5k4RARgegom6NzHsgTrO1fl5lo0mWKXUr5WWb2DEhtsmNdv9WIZrJR6CBlEsJjZMWLR5+JErKAI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791927821; c=relaxed/simple; bh=5F9BjAA+Rx1pAo6/tJI6LJBrrVV/VYMlVwqCpeqjzJc=; h=Message-ID:From:Subject:To:Cc:In-Reply-To:References:Content-Type: Date; b=WmIYyWGgNpufkmtTLkrwRzR9bIwaTTzF4MunVVXsmyG5EneSO4X6m/cHdL1LXd99jPHvlYIkJFPFBg67qPfxkQ6QCOKwtPsyWES92z69hknqbRbO6Tt+fRceiEzt3uuHX6zwsMRVOozvLy+0LwI3B0F68DWqJkC4K6go6Y3Q9S4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=YrZp/2GT; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="YrZp/2GT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 71F721F000FF; Tue, 13 Oct 2026 21:43:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1791927819; bh=5F9BjAA+Rx1pAo6/tJI6LJBrrVV/VYMlVwqCpeqjzJc=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=YrZp/2GTwGtUTM07MHuHPWVvOXUJgNzZrO6Brh/sm6TZQENPlI+IXO8gQXsp2kceN UYpM2a0WFRyADMZ+nNrIONeZre+vfNDuEDVocEZtiCN1bTHj13sBe43CvsN1EQlRJG HyZfH2xgFXUCXeEfr2iAwfa8hex8jnVszRj9VCKOihpuFgrguNhqB8bkaUjQr0BtEe UtyBaKMR3fXwxJ85aTiu0iGu2dYhIVpEZIOKKw0MDJ6RwuhxsQAkmbn8GlAdCav0Ff VRizhXbfkQp8LBQf+8uNvGgV+inDUl2u3y7EpGaLfXn4Sj+SI+cRnk5DDK/fo04npa VPe4nRZeB4+sQ== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH] tools: perf: allow opt-in "no-dso." files in /dev/shm Reply-To: sashiko-reviews@lists.linux.dev To: "Stephen Brennan" Cc: linux-perf-users@vger.kernel.org In-Reply-To: <20261013213842.1870582-1-stephen.s.brennan@oracle.com> References: <20261013213842.1870582-1-stephen.s.brennan@oracle.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 13 Oct 2026 21:43:38 +0000 Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: > Applications can place JIT-compiled code in POSIX shared memory so that > multiple processes can execute the same code. On Linux, these shared > memory objects appear as file mappings under /dev/shm. >=20 > Perf uses /tmp/perf-$pid.map to resolve symbols for executable SysV > shared memory mappings, but it treats /dev/shm mappings as ordinary > DSOs. As a result, applications which provide perf-map symbols for JIT > code in POSIX shared memory don't get those symbols resolved, while they > do with SysV shared memory. >=20 > It would be incorrect to classify every /dev/shm mapping as no-DSO > memory though, because /dev/shm is just a tmpfs mount, and it can > contain ELF files. >=20 > Add a filename prefix "/dev/shm/no-dso." which is recognized by > is_no_dso_memory(). Applications can opt-in by naming their shared > memory objects "no-dso.". Executable mappings with this prefix > will use the perf-map file, while other /dev/shm mappings will keep the > existing behavior. This allows applications that already emit perf maps > to use POSIX shared memory for JIT code, without needing to implement > jitdump support. >=20 > Signed-off-by: Stephen Brennan Sashiko has reviewed this patch and found no issues. It looks great! --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261013213842.1870= 582-1-stephen.s.brennan@oracle.com?part=3D1