From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=91.218.175.199 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793718648; b=hu0c4zAVSdt6YqfZuqBksuab3RR0Hm8KHFILTtFHZsUkH+zySyGBcYtsEnTgEjf8WFxt WPqNM22wzcXhXIT9HQwE/Yur4PciCz9zxpF/0bnWd+VOrqkdnHdF75Ae3ZDNIVlOhmWOv M0YMtGqHBv4T51jfDdYWIPNc6PafMdq7fmhluFDnGNoL3br7yz5jvEb6q4ThxrJyImaG4 PXFVnE7o89yi1j8+CDVrUFqUAsw6wB0E/eDhBtYCTY2o+8re0pWgr9tyYj+RJs+0j/vQw vEweKkn2//oGcF3coV8lQTofyomLnjVy6b1muH143clQL3+/g1zdBhXWi2/Ztz/Acag== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793718648; h=DMARC-Filter:X-Envelope-To:DKIM-Signature:X-Envelope-To:Received: X-Mizu-Trace-ID:X-Migadu-Flow:From:To:Cc:Subject:Date:Message-ID: X-Mailer:In-Reply-To:References:MIME-Version:Content-Type: Content-Transfer-Encoding; bh=69LtF5LxsSyai3V1zpFQvGHNKgI/ivVQp0YDn5JQf9U=; b=ttJOMkDNQDt6Vfiq2DZ4CVGgF2t3qABVEhbVfPHdVcuobOlW3nCCraDt5qPSn/hxQbOj qM1hssQDisKU7hQSmVwuApjv/R11kIiOIOdsfgSdQsaQ8AkyAKLVWEOId4RSyRcNHe7zF Jzc2SZQjRqv17I7ZX6ciK+FL9BaUo33jZzwd3drLt/twMZzfqwcI6W3b8Tm03D/8HAIa6 heVkoGBoLl9AOLOpIReusjuDycxrcI2pWwQJCYCsI0Z3UwApbU+tfX9XbEi1prebcEwbE +GwOZZLNXVamMgVVKmZoDFBy0z16Wi94AtIwZsSWJJ5bC8sg7Yuu0w9Te4KDxH+lPaA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=UbkPTj91; arc=none smtp.remote-ip=91.218.175.199 Received: from mta0.migadu.com (out-199.mta0.migadu.com [91.218.175.199]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 08536606D2ED for ; Tue, 3 Nov 2026 15:10:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 08536606D2ED Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=UbkPTj91 X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=5l77t2qq3L5LuFBcuy2fj7Ly2dABkuzVGXgG0cH9dIQ=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1793718644; v=1; x=1794323444; b=UbkPTj91uQeoBrTXtlO8oXMNemeWpw7UR3sGwP9qbCTHVpBJQuHtAZWT1LYODEQHlshd3I1E Zj3mQrGeIp71s7MwA7g4UxWFiEDhkPv5JxsZNKIXcF222h2m4nJb7J6ROYxh1/AK7VXtS05FFgJ PLdg+BCSwItMmMvEdO3j67Fs= X-Envelope-To: linux-kernel@vger.kernel.org Received: by mta11.migadu.com with ESMTPS id 5936257d9543480e; Tue, 03 Nov 2026 15:10:44 +0000 X-Mizu-Trace-ID: 5936257d9543480e X-Migadu-Flow: FLOW_OUT From: Usama Arif To: Huacai Chen Cc: Usama Arif , Andrew Morton , david@kernel.org, chrisl@kernel.org, kasong@tencent.com, ljs@kernel.org, ziy@nvidia.com, linux-mm@kvack.org, ying.huang@linux.alibaba.com, Baoquan He , willy@infradead.org, youngjun.park@lge.com, hannes@cmpxchg.org, riel@surriel.com, shakeel.butt@linux.dev, alex@ghiti.fr, kas@kernel.org, baohua@kernel.org, dev.jain@arm.com, baolin.wang@linux.alibaba.com, Nico Pache , "Liam R. Howlett" , ryan.roberts@arm.com, Vlastimil Babka , lance.yang@linux.dev, linux-kernel@vger.kernel.org, nphamcs@gmail.com, shikemeng@huaweicloud.com, yosry@kernel.org, qi.zheng@linux.dev, luizcap@redhat.com, kernel-team@meta.com Subject: Re: [PATCH v8 03/30] loongarch: mm: add PMD swap-exclusive helpers Date: Tue, 3 Nov 2026 07:10:35 -0800 Message-ID: <20261103151037.1621401-1-usama.arif@linux.dev> X-Mailer: git-send-email 2.53.0 In-Reply-To: References: X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On Fri, 2 Oct 2026 22:17:51 +0800 Huacai Chen wrote: > Hi, Usama, > > On Fri, Oct 2, 2026 at 5:55 PM Usama Arif wrote: > > > > Prepare for keeping a PMD-mapped anonymous THP mapped by a PMD across the > > swap round-trip, which makes PG_anon_exclusive have to survive in a swap > > PMD and not just in a swap PTE. > > > > A LoongArch swap PMD is the swap PTE value plus _PAGE_HUGE, and > > _PAGE_SWP_EXCLUSIVE sits outside both the type and the offset field, so the > > PMD helpers can use the same bit. > > > > Cc: Huacai Chen > > Signed-off-by: Usama Arif > > Reviewed-by: David Hildenbrand (Arm) > > --- > > arch/loongarch/include/asm/pgtable.h | 19 +++++++++++++++++++ > > 1 file changed, 19 insertions(+) > > > > diff --git a/arch/loongarch/include/asm/pgtable.h b/arch/loongarch/include/asm/pgtable.h > > index cf29a4c8ac593..87fecc3a51001 100644 > > --- a/arch/loongarch/include/asm/pgtable.h > > +++ b/arch/loongarch/include/asm/pgtable.h > > @@ -351,6 +351,25 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte) > > return pte; > > } > > > > +#ifdef CONFIG_ARCH_HAS_PMD_SOFTLEAVES > > +static inline pmd_t pmd_swp_mkexclusive(pmd_t pmd) > > +{ > > + pmd_val(pmd) |= _PAGE_SWP_EXCLUSIVE; > > + return pmd; > > +} > > + > > +static inline bool pmd_swp_exclusive(pmd_t pmd) > > +{ > > + return pmd_val(pmd) & _PAGE_SWP_EXCLUSIVE; > > +} > > + > > +static inline pmd_t pmd_swp_clear_exclusive(pmd_t pmd) > > +{ > > + pmd_val(pmd) &= ~_PAGE_SWP_EXCLUSIVE; > > + return pmd; > > +} > I think the order should be pmd_swp_exclusive, pmd_swp_mkexclusive and > pmd_swp_clear_exclusive. That looks more natural. > > The riscv version is already like this, but others are not. Done. The LoongArch helpers now use test/mk/clear. I also reordered s390's PMD helpers to match its adjacent PTE helpers. RISC-V and arm64 already use test/mk/clear for their PMD helpers. Powerpc and x86 retain the order used by their adjacent PTE helpers. > > > Huacai > > > +#endif > > + > > #define pte_none(pte) (!(pte_val(pte) & ~_PAGE_GLOBAL)) > > #define pte_present(pte) (pte_val(pte) & (_PAGE_PRESENT | _PAGE_PROTNONE)) > > #define pte_no_exec(pte) (pte_val(pte) & _PAGE_NO_EXEC) > > -- > > 2.53.0-Meta > > >