From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E1554D1D870 for ; Thu, 4 Dec 2025 06:52:32 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 32C8C6B0011; Thu, 4 Dec 2025 01:52:32 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 2DCC96B0012; Thu, 4 Dec 2025 01:52:32 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1F2896B0023; Thu, 4 Dec 2025 01:52:32 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 0BCA76B0011 for ; Thu, 4 Dec 2025 01:52:32 -0500 (EST) Received: from smtpin17.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 2C9A6C08C5 for ; Thu, 4 Dec 2025 06:52:29 +0000 (UTC) X-FDA: 84180870018.17.E5A05F1 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf05.hostedemail.com (Postfix) with ESMTP id 534A710000A for ; Thu, 4 Dec 2025 06:52:27 +0000 (UTC) Authentication-Results: imf05.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf05.hostedemail.com: domain of anshuman.khandual@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=anshuman.khandual@arm.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1764831147; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=RqFa2b+K3fcKtemSHIfEKXbku0CciHAsPdEHPf8F7c8=; b=sU7AlkJSV/iYW3aSn7mdLDInmL+DBU8nkhBRfsOua3SkliGh9P6VZnEAvcAaiQfAvECVXH OdycqhbkO8XpzjRQRN5LbRQpw7QA+shdJ/adCEWGnUguOKM1ksiBi9mf5Lsnz1cql6Bd6V y1SzXZxk0NNicCOXPEtccqNv8aKn0p0= ARC-Authentication-Results: i=1; imf05.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf05.hostedemail.com: domain of anshuman.khandual@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=anshuman.khandual@arm.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1764831147; a=rsa-sha256; cv=none; b=Szaonhb4xkPtqKYue07ZDrN7vIit4Yja8q/CxmpG4o5Tlo0eqLeejxCvyCnWcfwCmnma1g bk4QisTQ8SkzyTAe4/G5DsGPYkrlpNpOHgX0vZvT3P4Z5jWYuMSDZwZlC+lPEkId5/hhGz dvJlQGwh5gBA/zXSjOVSs0cIHfyWYLg= Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id AEABB339; Wed, 3 Dec 2025 22:52:18 -0800 (PST) Received: from [10.164.18.78] (unknown [10.164.18.78]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3C0333F59E; Wed, 3 Dec 2025 22:52:16 -0800 (PST) Message-ID: <89ecddb7-83ee-427b-823b-984204939ecf@arm.com> Date: Thu, 4 Dec 2025 12:22:13 +0530 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 09/12] arm64: mm: replace TIF_LAZY_MMU with in_lazy_mmu_mode() To: Kevin Brodsky , linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Alexander Gordeev , Andreas Larsson , Andrew Morton , Boris Ostrovsky , Borislav Petkov , Catalin Marinas , Christophe Leroy , Dave Hansen , David Hildenbrand , "David S. Miller" , David Woodhouse , "H. Peter Anvin" , Ingo Molnar , Jann Horn , Juergen Gross , "Liam R. Howlett" , Lorenzo Stoakes , Madhavan Srinivasan , Michael Ellerman , Michal Hocko , Mike Rapoport , Nicholas Piggin , Peter Zijlstra , "Ritesh Harjani (IBM)" , Ryan Roberts , Suren Baghdasaryan , Thomas Gleixner , Venkat Rao Bagalkote , Vlastimil Babka , Will Deacon , Yeoreum Yun , linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, xen-devel@lists.xenproject.org, x86@kernel.org References: <20251124132228.622678-1-kevin.brodsky@arm.com> <20251124132228.622678-10-kevin.brodsky@arm.com> Content-Language: en-US From: Anshuman Khandual In-Reply-To: <20251124132228.622678-10-kevin.brodsky@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Queue-Id: 534A710000A X-Rspamd-Server: rspam11 X-Stat-Signature: ji1qpaaze8bqs5t3syfa1ck1a1cnurn9 X-HE-Tag: 1764831147-644690 X-HE-Meta: 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 cUlX6tTc DTjg7HgZERAzt4Y9RDLA9mYXv7UZpYa5Voh1G5VN14fDW2+oFhfVe97VtuiMypj1jB0zscv1H2EkBz1CXnJc8+kLdTf8MLLPzdpoNtxGJpvFUPWKeMIQtSEsV7k3YlKnVCG8Gv3w+ksKN6SUIGKpqzvJA9oCOezGXVFCHye+KZHYvisRwSLGvG3w30EWguloVflI7awme9RwekEYbSXqRD11OjeV1DK/Oa5YEF7U7hZUcPbp/TEUM99liljS/PudU/n9VfLUBjtEaH29nxQpS3LYHUCXs5jPHEzBtYVZ66N2UCQCI/Uyuhp9+7MJ9YLg0qkF2 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 24/11/25 6:52 PM, Kevin Brodsky wrote: > The generic lazy_mmu layer now tracks whether a task is in lazy MMU > mode. As a result we no longer need a TIF flag for that purpose - > let's use the new in_lazy_mmu_mode() helper instead. > > The explicit check for in_interrupt() is no longer necessary either > as in_lazy_mmu_mode() always returns false in interrupt context. > > Signed-off-by: Kevin Brodsky > --- > arch/arm64/include/asm/pgtable.h | 19 +++---------------- > arch/arm64/include/asm/thread_info.h | 3 +-- > 2 files changed, 4 insertions(+), 18 deletions(-) > > diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h > index a7d99dee3dc4..dd7ed653a20d 100644 > --- a/arch/arm64/include/asm/pgtable.h > +++ b/arch/arm64/include/asm/pgtable.h > @@ -62,28 +62,16 @@ static inline void emit_pte_barriers(void) > > static inline void queue_pte_barriers(void) > { > - unsigned long flags; > - > - if (in_interrupt()) { > - emit_pte_barriers(); > - return; > - } > - > - flags = read_thread_flags(); > - > - if (flags & BIT(TIF_LAZY_MMU)) { > + if (in_lazy_mmu_mode()) { > /* Avoid the atomic op if already set. */ > - if (!(flags & BIT(TIF_LAZY_MMU_PENDING))) > + if (!test_thread_flag(TIF_LAZY_MMU_PENDING)) A small nit - will it be better not to use test_thread_flag() here and just keep checking flags like earlier to avoid non-related changes. Although not a problem TBH. > set_thread_flag(TIF_LAZY_MMU_PENDING); > } else { > emit_pte_barriers(); > } > } > > -static inline void arch_enter_lazy_mmu_mode(void) > -{ > - set_thread_flag(TIF_LAZY_MMU); > -} > +static inline void arch_enter_lazy_mmu_mode(void) {} > > static inline void arch_flush_lazy_mmu_mode(void) > { > @@ -94,7 +82,6 @@ static inline void arch_flush_lazy_mmu_mode(void) > static inline void arch_leave_lazy_mmu_mode(void) > { > arch_flush_lazy_mmu_mode(); > - clear_thread_flag(TIF_LAZY_MMU); > } > > #ifdef CONFIG_TRANSPARENT_HUGEPAGE > diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h > index f241b8601ebd..4ff8da0767d9 100644 > --- a/arch/arm64/include/asm/thread_info.h > +++ b/arch/arm64/include/asm/thread_info.h > @@ -84,8 +84,7 @@ void arch_setup_new_exec(void); > #define TIF_SME_VL_INHERIT 28 /* Inherit SME vl_onexec across exec */ > #define TIF_KERNEL_FPSTATE 29 /* Task is in a kernel mode FPSIMD section */ > #define TIF_TSC_SIGSEGV 30 /* SIGSEGV on counter-timer access */ > -#define TIF_LAZY_MMU 31 /* Task in lazy mmu mode */ > -#define TIF_LAZY_MMU_PENDING 32 /* Ops pending for lazy mmu mode exit */ > +#define TIF_LAZY_MMU_PENDING 31 /* Ops pending for lazy mmu mode exit */ > > #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) > #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) LGTM. Hence with or without the 'flags' changes in queue_pte_barriers() above. Reviewed-by: Anshuman Khandual