From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sender4-op-o15.zoho.com (sender4-op-o15.zoho.com [136.143.188.15]) (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 76F8624501E for ; Thu, 10 Jul 2025 10:58:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.15 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752145087; cv=pass; b=jONXU0F0agq34/Zca6/9NW0KFxup6gpzv7TN/oz8qCGDe6BhDWZXNpGZhcm0Co35PiK5i1BhElXXrFJNOsSluh+kyyyyaUwItG5O4Mw2bdIOF1oG5TkTG3uEmzjzjyxoDTnIs7/ui5DLxGS1ZLhK7qSC0wfT+cndZ30Sl6CtRow= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752145087; c=relaxed/simple; bh=JzOEzQ4u4rtw2NIBLOcRDtDefM3sgL3nRVZ/m4mk2yc=; h=From:To:Subject:Date:Message-ID:MIME-Version:Content-Type; b=ulyX8Kje7imuyQ3tgCEFg4kPScU6pg2Q5NmzpXW1GJtcDo63rdOyMjplQGy5hQoK2f03vZRn1yQHPDnvLUxJVz7l/Vxh+VHXDQ4k/DTCxZFRjREGtzYOO+R2Y55ModKzyigYABHW9AKQZrXVgSXjHBRu26IaTsaZ6xo79LBPMdQ= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linux.beauty; spf=pass smtp.mailfrom=linux.beauty; dkim=pass (1024-bit key) header.d=linux.beauty header.i=me@linux.beauty header.b=Y2amTz0t; arc=pass smtp.client-ip=136.143.188.15 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linux.beauty Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.beauty Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.beauty header.i=me@linux.beauty header.b="Y2amTz0t" ARC-Seal: i=1; a=rsa-sha256; t=1752145042; cv=none; d=zohomail.com; s=zohoarc; b=C7R/uEgzS8DBaItptc8pmQ/N4XdTC9BtVmSrxUSFnurBo3Sx8VY9jI3eQstJ4XxE4V63oX6AzD1BnsnQCZItvMBIICSVHmEbj3iyX3uxsGQvs4mDQKegxr+qND0yKObhqQXpSBgUtR89uhUsVK9hhd5HkTKVHVWe7LZAfMMHBrM= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1752145042; h=Content-Type:Content-Transfer-Encoding:Date:Date:From:From:MIME-Version:Message-ID:Subject:Subject:To:To:Message-Id:Reply-To:Cc; bh=yiEYKiYWi9lfEelzgS689BygDZKCSEUDoT6dG+OBGmU=; b=U/bnAvbtIfwE1blvERtTfUL+ZMXe36eRgIzSyTGqCbcT8R1lbhqZtIWFQ7uXDXvAa4x3/l+VWGt/aHal7XlneKHg7d1LityuLX3oFGdg7aXAzT4JcEaNbL0hZunTkmJSOoBwzA5P3lYM/VpnO0FrZ8QS5HQtQTPpn/DfxBUiwH4= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=linux.beauty; spf=pass smtp.mailfrom=me@linux.beauty; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1752145042; s=zmail; d=linux.beauty; i=me@linux.beauty; h=From:From:To:To:Subject:Subject:Date:Date:Message-ID:MIME-Version:Content-Type:Content-Transfer-Encoding:Message-Id:Reply-To:Cc; bh=yiEYKiYWi9lfEelzgS689BygDZKCSEUDoT6dG+OBGmU=; b=Y2amTz0tziV140SrHvT24YTRFZsci/hGRpokwl7qkJ3dGbwNKqkEmjfgKaoiQ9mG nt1IOua+FpOfW0XDBNB3cbXLCJPjjIye8RgZ+VfIxK6HaPDrSPRoRRQdVXVtEHXOoMM Phxf8//u3GA64BoPaBrnyaCr2P5e1oNUhuP6Kxy0= Received: by mx.zohomail.com with SMTPS id 1752145040240481.87790057866744; Thu, 10 Jul 2025 03:57:20 -0700 (PDT) From: Li Chen To: "Thomas Gleixner" , "Ingo Molnar" , "Borislav Petkov" , "Dave Hansen" , x86@kernel.org, "H . Peter Anvin" , "Rafael J . Wysocki" , "Peter Zijlstra" , "Sohil Mehta" , "Brian Gerst" , "Patryk Wlazlyn" , linux-kernel@vger.kernel.org Subject: [PATCH v5 0/4] x86/smpboot: tidy sched-topology and drop useless SMT level Date: Thu, 10 Jul 2025 18:57:06 +0800 Message-ID: <20250710105715.66594-1-me@linux.beauty> X-Mailer: git-send-email 2.50.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-ZohoMailClient: External From: Li Chen This series cleans up sched-domain topology handling and eliminates hundreds of pointless attach/destroy cycles for large machines when SMT is not available. Patch 1, 2, and 3 do some cleanup and refactor. Patch 4 is a follow-up that simply skip SMT domain when cpu_smt_num_threads <= 1, so the SMT level never gets created. Tested on Qemu. changelog: v2: fix wording issue as suggested by Thomas [1] v3: remove pointless memset and adjust PKG index accordingly, as suggested by Thomas [2], and refine some other wording issues. v4: v4: Split refactor patche into three parts (as suggested by Peter [3]) and refined patch 4 logic (as done by K. [4]). v5: fix some style issues and do some improvements as pointed out by K. [5][6] [1]: https://lore.kernel.org/all/87msa2r018.ffs@tglx/ [2]: https://lore.kernel.org/all/875xglntx1.ffs@tglx/ [3]: https://lkml.org/lkml/2025/6/25/584 [4]: https://lore.kernel.org/lkml/1b706790-2fec-4582-a425-55eeff36c32e@amd.com/ [5]: https://lore.kernel.org/all/f391491d-f886-4579-9b40-78a57f2ed1b5@amd.com/ [6]: https://lore.kernel.org/all/7e7f686b-1f5a-46dc-8b16-c6d491160d1c@amd.com/ Li Chen (4): smpboot: introduce SDTL() helper to tidy sched topology setup x86/smpboot: remove redundant CONFIG_SCHED_SMT x86/smpboot: moves x86_topology to static initialize and truncate x86/smpboot: avoid SMT domain attach/destroy if SMT is not enabled arch/powerpc/kernel/smp.c | 34 +++++++++-------------- arch/s390/kernel/topology.c | 10 +++---- arch/x86/kernel/smpboot.c | 51 ++++++++++++++++------------------ include/linux/sched/topology.h | 4 +-- kernel/sched/topology.c | 24 ++++++---------- 5 files changed, 52 insertions(+), 71 deletions(-) -- 2.50.0