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X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org On Tue, Sep 22, 2026 at 04:35:37PM +0100, Lorenzo Stoakes (ARM) wrote: >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. > >Acked-by: Kiryl Shutsemau (Meta) >Signed-off-by: Lorenzo Stoakes (ARM) >--- Also ran page-table teardown stress on qemu-system-sparc64 (sun4u, UP). That ran cleanly too ;) Feel free to add: Tested-by: Lance Yang Acked-by: Lance Yang _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv