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 8E0E14CB8B9 for ; Sun, 18 Oct 2026 14:31:36 +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=1792333897; cv=none; b=UM8zUvt1BGpEwqQ25p9WDURomHqw1XxkOd3ayoyzjRw9cDF5wTL5Mcuc6qs0epLx2K1AmQDqiF4J/fgPytMopU83U84WT5UNrMl84KN9+1jW+s1ENhD6G2+qYd7oJc66XVYhXRWuN6TCDbmlgWPv8ACr827Yee0RVd8ZRRDOHLA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792333897; c=relaxed/simple; bh=iJbiF3CXs8QJmkANJOSRUIRpbk1bCfhs/VjmwCMmrYQ=; h=Message-ID:From:Subject:To:Cc:In-Reply-To:References:Content-Type: Date; b=cYjJ5iWdArWQKf9v/uxaN+sk4oYJ2DfrAk7zsbMl1MKMiMk+2z1M5KCi+IdbQ6t0l1uwKWkr4V2ndzmc+XEe81zcow8Ba+ocD1b8izBxA4VbkQDdqR4BRPWOQfH4Vc800N4lJD0AaQIJ+CbR8T0WHq2TsS0FEVaSk0Q1ZJqJrOA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Hk/NKFBc; 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="Hk/NKFBc" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 06D0C1F000C4; Sun, 18 Oct 2026 14:31:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792333896; bh=iJbiF3CXs8QJmkANJOSRUIRpbk1bCfhs/VjmwCMmrYQ=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=Hk/NKFBcW20ExK6wCGfDqg47XC+WjIQdlmStpD4uKobFIakATs7HPAFZ9D9c0YL/U 6cNz4YrqZp+xH83k1yiCyb+BRhyo+UDHEDZL5mF6NaaqDxv5e7GQ0axqnhzXLj3N3b 1Rdi28C24JD3BCXrrj1kB/RGEre0yRpPBWuJoMu6PGa3wFGWBBWl3xaF3p11oFqMt7 dSfSGI8ndtZ/2ZkzNgO5j+/WbGm3LkLcJungu0bkwXshEEzdILSYGnox6DrZsVKEN6 bQmtUCeS4g3P1ZBi9j0qn89COd2GMoGcTKyZp/u3XLnh5hFmnUBwfMTm6rA7RyihZ+ 7OkRLytlBEdXg== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v3 5/5] alpha: fill in pc for software event samples Reply-To: sashiko-reviews@lists.linux.dev To: "Matt Turner" Cc: linux-perf-users@vger.kernel.org In-Reply-To: <20261018-alpha-perf-regs-v3-v3-5-52be85332c57@gmail.com> References: <20261018-alpha-perf-regs-v3-v3-0-52be85332c57@gmail.com> <20261018-alpha-perf-regs-v3-v3-5-52be85332c57@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Sun, 18 Oct 2026 14:31:35 +0000 Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: > Context switch and tracepoint events have no trap frame, so perf builds > one with perf_fetch_caller_regs(). Alpha does not define > perf_arch_fetch_caller_regs(), which leaves that pt_regs zeroed, and > these samples report pc as 0. >=20 > Record the caller's address as pc. The zero ps already marks the frame > as kernel mode, and pt_regs has nowhere to keep sp, so pc is all that > can be filled in. >=20 > perf_fetch_caller_regs() gets that address from CALLER_ADDR0, which > alpha defines as 0 when CONFIG_FRAME_POINTER is disabled. Finding the > level zero return address does not need a frame pointer, so make > alpha_ftrace_return_address0() available in both configurations. Only > ftrace_return_address(n) still depends on frame pointers. >=20 > Reported-by: Magnus Lindholm > Suggested-by: Magnus Lindholm > Closes: https://lore.kernel.org/all/CA%2B%3DFv5S8-Zk8-LUpZnWiBfTGSQXthepm= Rc_-a9O%2BpEPmVW0mRA@mail.gmail.com/ > Assisted-by: Claude:claude-opus-5-5 > Reviewed-by: Magnus Lindholm > Acked-by: Ian Rogers > Signed-off-by: Matt Turner Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261018-alpha-perf= -regs-v3-v3-0-52be85332c57@gmail.com?part=3D5