From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f52.google.com (mail-wm1-f52.google.com [209.85.128.52]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E12863B8D72 for ; Sun, 7 Dec 2025 12:16:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.52 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765109766; cv=none; b=Nldh7hDs5k7TUZN5dskS2G3JoOTbMsb3vcp5iIz8wPLWXoURWp2vV+koMOYuzbJbdjihl9EjcU/MMFoRM/kPeonqdalYHeVlEgSoeR14Z5VeM/y/XzVlz3RZZXG4avxlmjYZfK/NZoQBD7OQMt5MvN8b2Tom73O6WbluYXYx1FQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765109766; c=relaxed/simple; bh=FEbxVk7wmKJ4CC4mXv63i7iPIqvwX42991mwrYLOP9A=; h=Content-Type:Mime-Version:Subject:From:In-Reply-To:Date:Cc: Message-Id:References:To; b=DQZ3Oe7ULShImxvc9V2XqN7xdaKOQI8/wNN+pWCUbY9CTxB6lL85OD223S5Fi2kNcSkMF52kD/Vh5AwK3MtFCKF2/jP/9fSmNJumX/+KUSLqpI3uuhyQpmXYrRJ/KOMz6UQhhf8ZNgegqtXtQN5FraeyZ1mqpG+eF5v9oMfSQfw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=XhSkg754; arc=none smtp.client-ip=209.85.128.52 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="XhSkg754" Received: by mail-wm1-f52.google.com with SMTP id 5b1f17b1804b1-477a2ab455fso43433075e9.3 for ; Sun, 07 Dec 2025 04:16:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1765109762; x=1765714562; darn=vger.kernel.org; h=to:references:message-id:content-transfer-encoding:cc:date :in-reply-to:from:subject:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=QT4cc6ryECaLEhMTXcgpX95Fpt+0IiUEEALeoLDPVjE=; b=XhSkg754tkUXStSL0vmaw0JsKZ6eF48IZ3n7GUskD215RpVmMnh5yrOiGNmiuahhf1 rBeJMvmkoSgTl9WMoV4kpool1D4DT4K9QaMxC4iOMGJ/D3N0oJWK4grhr05F25qFbTrm TExxG9wPxoqP2uuhsx9CE54vBCLog+RvWGCzfvONsgHXaRMBCulX04HQWzk3dDb9vLrD oR0oTwvEzXlTTnIqEVa8ZC2BVHoZlwWMWtrY/cUX9doojeYhv1QdWJsb8eEAIzl4wWYb juVt9GgsRBa7jFvD/wMQP3gLQ56EGU9TO+WCdVk5cgmSDhxy+GcmUetsS5Zfg+j3cRCj OIng== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1765109762; x=1765714562; h=to:references:message-id:content-transfer-encoding:cc:date :in-reply-to:from:subject:mime-version:x-gm-gg:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=QT4cc6ryECaLEhMTXcgpX95Fpt+0IiUEEALeoLDPVjE=; b=qvgfF6pccwH3YFzm9vCu7JfaZxI/YguK93+DTggFsP5oQRTnYB/zJ/VHDiM7yQWkQJ +QxfpM3DHVdk+2c8aJBTzB+rCjpoClZVzGMzav91ym33rwEiANbdADikYPEcG+bvKhFz smmkRbkyMA2DY9j+/23EYE7j7y/8xlxZcRTWDy/vXk7plX1Pa0VpkI64rBu17d+8LkSP Nfy/qOJsyMbFqt1CSsWZ9eIhAMaE3Y8LimYOzIts2BAI6guUMu1l7ehACeosHoXOamsa K61QyR0YcsPtw+f71bxxgeHrfeAWXBQmFxWUv1WC1fppna0h7Vz5bPtZv4tzZ+lfH4FX 6H4g== X-Gm-Message-State: AOJu0YzrP0CPLzMR77qQdwO+9uYjn/TmQmrs1huh66l9iPi27Jc0FFfQ RVdlNmehlRrJft2808inT/Oympgr23KBM/P74cjiqWbCueMsXglt2ZMP X-Gm-Gg: ASbGnctC5C2ZZqWfdnlAsDo9sNHqCfRgPaapMxMmqEDbsysea3tp2h9vepjy4xUJMYW 4GsUb0Kifh8NJxS9XrfoJWStM6PcG3UlqEbEsyYowJCRd5FxvN99SS0m4FYeAblh/39ZdtrNGwv 9RUlO+h8X/7p2UjpqtUHZsJ1Jjdg6c3Tq351jYGQP4QDOC1txHeOf2WXGgXcoZoHrr8Ae3WOS5T zK1SRciKCn38EjVJJdH3UPJOolpA0zdnHaKa6jbAXMEwNgVB/q3o/Tp4phn5wyD+fTaqXJxtckl H4L5TX+d0Ok1fEAN+lJksVQHXT4HtW/e6i92kzJ6j1u0Fgv4W6neUK6P/UMErKu9KCFn5eFQmuO qOquTg7/q+9LKHNbRRoMyQ2k4FqgHl1lmH93vjLFIFGVSN8T/uN/YOtwTeW/TIlR6SGbykZRyBA eDWbP6ztCEhBeOaHakvNQRKBw+lajQo+c= X-Google-Smtp-Source: AGHT+IHC8ivIALeWoT4SzaWmpNaTZ5behrXBR6LHuS1Z2YNL9+AnBuHGkZlkWoEmSgwayqVBsaaMLw== X-Received: by 2002:a05:600c:524a:b0:477:9b35:3e36 with SMTP id 5b1f17b1804b1-47939df1419mr40530125e9.2.1765109761978; Sun, 07 Dec 2025 04:16:01 -0800 (PST) Received: from smtpclient.apple ([212.59.70.42]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-479311e707asm181916185e9.10.2025.12.07.04.15.58 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Sun, 07 Dec 2025 04:16:00 -0800 (PST) Content-Type: text/plain; charset=utf-8 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3864.200.81.1.6\)) Subject: Re: [PATCH v1 4/4] mm/hugetlb: fix excessive IPI broadcasts when unsharing PMD tables using mmu_gather From: Nadav Amit In-Reply-To: <20251205213558.2980480-5-david@kernel.org> Date: Sun, 7 Dec 2025 14:15:47 +0200 Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, Will Deacon , "Aneesh Kumar K.V" , Andrew Morton , Nick Piggin , Peter Zijlstra , Arnd Bergmann , Muchun Song , Oscar Salvador , "Liam R. Howlett" , Lorenzo Stoakes , Vlastimil Babka , Jann Horn , Pedro Falcato , Rik van Riel , Harry Yoo , Laurence Oberman , Prakash Sangappa , stable@vger.kernel.org Content-Transfer-Encoding: quoted-printable Message-Id: <0914A8DB-447C-4E62-B151-62E5E4E99749@gmail.com> References: <20251205213558.2980480-1-david@kernel.org> <20251205213558.2980480-5-david@kernel.org> To: "David Hildenbrand (Red Hat)" X-Mailer: Apple Mail (2.3864.200.81.1.6) > On 5 Dec 2025, at 23:35, David Hildenbrand (Red Hat) = wrote: >=20 > @@ -400,6 +411,7 @@ static inline void __tlb_reset_range(struct = mmu_gather *tlb) > tlb->cleared_pmds =3D 0; > tlb->cleared_puds =3D 0; > tlb->cleared_p4ds =3D 0; > + tlb->unshared_tables =3D 0; > /* > * Do not reset mmu_gather::vma_* fields here, we do not > * call into tlb_start_vma() again to set them if there is an I understand you don=E2=80=99t want to initialize fully_unshared_tables = here, but tlb_gather_mmu() needs to happen somewhere. So you probably want it to take place in tlb_gather_mmu(), no?