From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 D7EF5534475; Tue, 8 Sep 2026 12:34:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788870895; cv=none; b=ljODYydKoin3kRBt7x0uIfLMOOep+V2+tG1b2lYjMv+8kIdLP3pa0GKLb9w5z/KaWpbcs01FIQtlhLZ4NG15VmoStutsh7HcSDQARWtzxSbRCf2Y934Aoh2YdjJqUHnwBJsAFeDse3Ba3pfJgpOSwBrRFhr4uugeq5SGnNOJKok= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788870895; c=relaxed/simple; bh=+cl/mE+MMAULPxyBPFJXsNZLkn5nuULAZlZa1FGDhyY=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=XQBvKdbtHwEv3WgDYeR0irwEmcR6KkaaRWupxUoBF+zyRxGiq/qnI0F62aNatMv2oOQ/fxptVtCkZAatJznJn0ZbWY91kn7+Cay2RdebQDsaZvyLJpnX9ucBhC4hoiPcjbsAidiYEN1fR2ge1h8QYSztvFd3npS/Uiaf5si5I7g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=BkBhZQWM; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="BkBhZQWM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7A1661F00A3A; Tue, 8 Sep 2026 12:34:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788870893; bh=2RQcemfGMYTiDH29zfMnTtdgj0bHtOblVlsFhLPlSxk=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=BkBhZQWMJaKKK3kWxqiV0sRE5ApAZKRcLKBomVjsdDgfY+tP7URW39FuystAZN++H HQ7wqjHB/37EVGJIuwiSGmfTp7Vp8T/jU0DMjRS4P9klDLrGCj2Qgu+A6lGKXNczH1 KJk4+Exs2cODA1A1Lu3ZQULVnsj0o5ldTr8gRlTAs6WV4+Eopslz62zHBRXBjdEVtW hZ/N9yTzYdMknuV+LXXwqefUBW5vIRH3y297e01EmAEhvvwopzgh/oDKM8BVvAv5W7 0dJYrcsCtLdY8mL+iq+uQniVYRfzb5b9GZPzOV4w5hpwmFRg+SIxYSL8Mq+929rq4+ Ys06pk+5Bfl3g== From: "Lorenzo Stoakes (ARM)" Date: Tue, 08 Sep 2026 13:32:15 +0100 Subject: [PATCH v2 06/12] mm: enable MMU_GATHER_RCU_TABLE_FREE for sparc64 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: 7bit Message-Id: <20260908-rcu-pagetable-freeing-v2-6-1f60b64e878e@kernel.org> References: <20260908-rcu-pagetable-freeing-v2-0-1f60b64e878e@kernel.org> In-Reply-To: <20260908-rcu-pagetable-freeing-v2-0-1f60b64e878e@kernel.org> To: Andrew Morton , David Hildenbrand , Zi Yan , Baolin Wang , "Liam R. 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Peter Anvin" , Arnd Bergmann , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jason Gunthorpe , John Hubbard , Peter Xu Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-openrisc@vger.kernel.org, linux-sh@vger.kernel.org, linux-riscv@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-snps-arc@lists.infradead.org, linux-arch@vger.kernel.org, sparclinux@vger.kernel.org, linux-alpha@vger.kernel.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-um@lists.infradead.org, Hugh Dickins , Qi Zheng , "Lorenzo Stoakes (ARM)" X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=2421; i=ljs@kernel.org; h=from:subject:message-id; bh=+cl/mE+MMAULPxyBPFJXsNZLkn5nuULAZlZa1FGDhyY=; b=owGbwMvMwCV2fu7ZrsZH9SKMp9WSGLIWMESv2xKd48fI8mtTui4Ta/hp+d28Xu9rvA5wmH5vi 71/9fG/jhIWBjEuBlkxRZbnX8T3B4mEzeu84O8GM4eVCWQIAxenAExEtYzhx96CQv0jOvtW8Zx5 zXvjpdqkgMTXKRbHTaKeac+Ii+z4y8jQsigg8NunuC3bHPzfFqmkzHQ20pkho1xRW8x8/Nbx329 ZAA== X-Developer-Key: i=ljs@kernel.org; a=openpgp; fpr=E7F417BF5214569E89D04F46CF9DCD8A81E27F14 Commit 4a0100f7546f ("sparc64: use RCU page table freeing") enabled CONFIG_MMU_GATHER_RCU_TABLE_FREE for SMP sparc64 architectures, expressly for GUP-fast page table walkers. Naturally, UP systems do not have to worry about concurrent GUP fast operations. However, CONFIG_PREEMPT_RCU is also available even on a UP system, so a future pure-RCU page table walker requires MMU_GATHER_RCU_TABLE_FREE to be enabled on UP, even if concurrent GUP fast is not possible there. To enable future pure-RCU page table walkers, enable MMU_GATHER_RCU_TABLE_FREE unconditionally. With this change, it is no longer necessary to have !CONFIG_SMP pgtable_free_tlb(), so also remove this now dead code. This forms part of an overall effort to switch every architecture to this mode. Signed-off-by: Lorenzo Stoakes (ARM) --- arch/sparc/Kconfig | 4 ++-- arch/sparc/include/asm/pgalloc_64.h | 8 -------- 2 files changed, 2 insertions(+), 10 deletions(-) diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index ab77d3f2536e..8d42ebc6d302 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -75,8 +75,8 @@ config SPARC64 select HAVE_FUNCTION_GRAPH_TRACER select HAVE_KRETPROBES select HAVE_KPROBES - select MMU_GATHER_RCU_TABLE_FREE if SMP - select HAVE_ARCH_TLB_REMOVE_TABLE if SMP + select MMU_GATHER_RCU_TABLE_FREE + select HAVE_ARCH_TLB_REMOVE_TABLE select MMU_GATHER_MERGE_VMAS select MMU_GATHER_NO_FLUSH_CACHE select HAVE_ARCH_TRANSPARENT_HUGEPAGE diff --git a/arch/sparc/include/asm/pgalloc_64.h b/arch/sparc/include/asm/pgalloc_64.h index caa7632be4c2..b5055d259b74 100644 --- a/arch/sparc/include/asm/pgalloc_64.h +++ b/arch/sparc/include/asm/pgalloc_64.h @@ -74,8 +74,6 @@ void pte_free_defer(struct mm_struct *mm, pgtable_t pgtable); void pgtable_free(void *table, bool is_page); -#ifdef CONFIG_SMP - struct mmu_gather; void tlb_remove_table(struct mmu_gather *, void *); @@ -96,12 +94,6 @@ static inline void __tlb_remove_table(void *_table) is_page = true; pgtable_free(table, is_page); } -#else /* CONFIG_SMP */ -static inline void pgtable_free_tlb(struct mmu_gather *tlb, void *table, bool is_page) -{ - pgtable_free(table, is_page); -} -#endif /* !CONFIG_SMP */ static inline void __pte_free_tlb(struct mmu_gather *tlb, pte_t *pte, unsigned long address) -- 2.55.0