From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f198.google.com (mail-pl1-f198.google.com [209.85.214.198]) (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 9B0FF21FF2A for ; Sat, 3 Oct 2026 00:21:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.198 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790986906; cv=none; b=JlNm4iPHyNStzI8xLy1olXrPiqIB9JHTr2eewqWUGZ4CEBVELTNTYDBMbkiAxXCbHPFEOCTJYJ15a36e5Kt5HzIjhC71DkPlJFDb00TevXDs/iT6ZMHl1irRYIItLdwL1PQ3l06PLFtrefRa72czRgO+ZBMaZ7yOtQn7wWv/vP8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790986906; c=relaxed/simple; bh=/Uog/olHbJL3eoKXUOpYt4JihD2R8HVABatRqtZ74rk=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=ts/ADc9y4xtcU3y5gCYuIIR7E8FjccpK5lpIaaAGtML5SJ9AbcI9OposhNv7KKaGH58tssKxHYJZ0oDXAmL02uZqYTYLpuX3LlYTyyV9H7zoZZnfClx7Vl0xia1ZVADWnYTnHUg2x1SlKJQS8pCX3ui63+URMxF2MlJrLmgnffI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--jthoughton.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=Pmir8geS; arc=none smtp.client-ip=209.85.214.198 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--jthoughton.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Pmir8geS" Received: by mail-pl1-f198.google.com with SMTP id d9443c01a7336-2df8484f12cso3925ad.3 for ; Fri, 02 Oct 2026 17:21:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1790986900; x=1791591700; darn=vger.kernel.org; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:from:to:cc:subject:date:message-id:reply-to :content-type; bh=+0LSbObtLQixt10mRMgsu561+yH+1K8mdQenqKY5U4A=; b=Pmir8geSI+efC6da9ZDriD/xr63hhFDdpI1zD3bKG5/HUvZqOpRjAqzY3zGbwpCodz 3IsZZEX8oQKX+PhZATrasHBxwYj3dmpg+wfVTBKoiYxG3xTjRQqhhcRBqeCjeaShm3gS nSY2nRSOFNBn9fAKayzoqa0lEQMKSL+plVjajrzwFCJAU5J12Tmj103GzQYJUGAgiq63 mz35OdqgC+dW4HVFwkfdpyncXJ4bjI8iLo9Ey84RoxKXIRE8m7SXHIC+dOYeFLlb0CVK qXy04jrBFTEuXndgGRw3OjeSBzBjruPvng7lMA89uGoF9X4Z53U9bBu1mqnmPKmFJ/6C omCw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1790986900; x=1791591700; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=+0LSbObtLQixt10mRMgsu561+yH+1K8mdQenqKY5U4A=; b=B7tQ/UiAstS0FnWzUgs6hx51osjOBpOeKjm+1kRZaxQcmuGYM7zdxNFeKD02ddEwjT ovF4iFGrPcKUySI7oyko4ZX06pR9CJZCdYrm6p2s6zOQmw/ziKuCDExkDPTTc/QjuzQH wwVHIgQ3J0sxFs5JFlSF/aXUPdWDs+9a4onG+cswBMcFbgSvYSm75u+6AiO7jOOCRcfU QolhNmi3d1GMH03IMMHr0a9P2BmqIfKyCXYgwVKx/A3hAIqze3r6A5US+mMFP8qbDEBn ps4DU1cvsnUNzFPFoBWciGEqAlvn43odozHtT9Vf78N6ME0wHmPEVU5tazhJbRclsj8y 8uig== X-Forwarded-Encrypted: i=1; AKwUvBwLTA5/QT24KX+Z/2cN2cAQZHseJxwF+ZoLiKsvw1c0YGp1T08NyEdpGYmXHG2ggkPNgq0MpkbmkBBHgF4=@vger.kernel.org X-Gm-Message-State: AFq9FYLSQ+Y7QR14qNGxTphDeyD1GiJzz9dj/ZeSMmoR1XseeXTW2hju lJFnhT10QHcfiv4fK3asf20CwoCr4OIA84tfTYzlctHPQVCJbDfAJyGjZTNkalj2K4kLmFBYB0l PrtKGkRfed5ev0Kvu+V7kfg== X-Received: from plev16.prod.google.com ([2002:a17:903:31d0:b0:2e2:c8c0:e8e2]) (user=jthoughton job=prod-delivery.src-stubby-dispatcher) by 2002:a17:902:e88c:b0:2df:ad58:cf54 with SMTP id d9443c01a7336-2e49b60b6c4mr40943675ad.34.1790986899505; Fri, 02 Oct 2026 17:21:39 -0700 (PDT) Date: Sat, 3 Oct 2026 00:21:09 +0000 In-Reply-To: <20261003002123.505555-1-jthoughton@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20261003002123.505555-1-jthoughton@google.com> X-Mailer: git-send-email 2.56.0.rc1.315.gc6ed9934b7-goog Message-ID: <20261003002123.505555-7-jthoughton@google.com> Subject: [PATCH v2 06/20] hugetlb_vmemmap: Allow architectures to dynamically disallow HVO From: James Houghton To: Will Deacon , Catalin Marinas , Muchun Song , Oscar Salvador , Andrew Morton Cc: Nikos Nikoleris , Linu Cherian , Mark Rutland , David Hildenbrand , Ryan Roberts , Nanyong Sun , Yu Zhao , Frank van der Linden , David Rientjes , James Houghton , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org Content-Type: text/plain; charset="UTF-8" For arm64, only some platforms support HVO. Add an arch hook to prevent HVO from taking affect if the architecture lacks support. It may be the case that arch_supports_hugetlb_vmemmap_optimization() returns false at first but eventually returns true. This is the case on arm64. When this happens, bootmem hugepages won't be immediately HVOed, but they will be optimized in prep_and_add_bootmem_folios(). Signed-off-by: James Houghton --- include/asm-generic/hugetlb.h | 7 +++++++ mm/hugetlb_vmemmap.c | 12 ++++++++++++ 2 files changed, 19 insertions(+) diff --git a/include/asm-generic/hugetlb.h b/include/asm-generic/hugetlb.h index 635c41cc3479..8d24075d53d4 100644 --- a/include/asm-generic/hugetlb.h +++ b/include/asm-generic/hugetlb.h @@ -128,4 +128,11 @@ static inline bool gigantic_page_runtime_supported(void) } #endif /* __HAVE_ARCH_GIGANTIC_PAGE_RUNTIME_SUPPORTED */ +#ifndef __HAVE_ARCH_HVO_SUPPORTED +static inline bool arch_hugetlb_vmemmap_optimization_supported(void) +{ + return IS_ENABLED(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP); +} +#endif /* __HAVE_ARCH_HVO_SUPPORTED */ + #endif /* _ASM_GENERIC_HUGETLB_H */ diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c index 3fdb1e4ce1a1..8596a462fee6 100644 --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include "hugetlb_vmemmap.h" @@ -529,6 +530,9 @@ static bool vmemmap_should_optimize_folio(const struct hstate *h, struct folio * if (!READ_ONCE(vmemmap_optimize_enabled)) return false; + if (!arch_hugetlb_vmemmap_optimization_supported()) + return false; + if (!hugetlb_vmemmap_optimizable(h)) return false; @@ -731,6 +735,14 @@ void __init hugetlb_vmemmap_optimize_bootmem_page(unsigned long pfn, unsigned in if (!READ_ONCE(vmemmap_optimize_enabled)) return; + /* + * Architectures may return false here but true by the time + * hugetlb_init() is called. In this case, although the folios will + * not be pre-HVOed, they will be optimized in hugetlb_init(). + */ + if (!arch_hugetlb_vmemmap_optimization_supported()) + return; + section_set_compound_order_range(pfn, 1UL << order, order); } -- 2.56.0.rc1.315.gc6ed9934b7-goog