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[70.30.145.63]) by smtp.gmail.com with ESMTPSA id t8-20020ac85888000000b003bb8c60cdf1sm1558142qta.78.2023.02.25.08.31.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 25 Feb 2023 08:31:57 -0800 (PST) From: Peter Xu To: qemu-devel@nongnu.org Cc: Maxim Levitsky , Stefan Hajnoczi , Juan Quintela , Paolo Bonzini , David Hildenbrand , "Dr . David Alan Gilbert" , Chuang Xu , =?utf-8?q?Philippe_Mathieu-Daud?= =?utf-8?q?=C3=A9?= , peterx@redhat.com Subject: [PATCH RFC 4/4] memory: Use rcu traversal in memory_region_to_address_space Date: Sat, 25 Feb 2023 11:31:41 -0500 Message-Id: <20230225163141.1209368-5-peterx@redhat.com> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230225163141.1209368-1-peterx@redhat.com> References: <20230225163141.1209368-1-peterx@redhat.com> MIME-Version: 1.0 Received-SPF: pass client-ip=170.10.129.124; envelope-from=peterx@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org memory_region_to_address_space() is the only function that walks the address_spaces list using RCU read lock only. Use the RCU walker to reflect that. Signed-off-by: Peter Xu --- softmmu/memory.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/softmmu/memory.c b/softmmu/memory.c index 95cdcaeccf..0b652d9597 100644 --- a/softmmu/memory.c +++ b/softmmu/memory.c @@ -566,7 +566,7 @@ static AddressSpace *memory_region_to_address_space(MemoryRegion *mr) while (mr->container) { mr = mr->container; } - QTAILQ_FOREACH(as, &address_spaces, address_spaces_link) { + QTAILQ_FOREACH_RCU(as, &address_spaces, address_spaces_link) { if (mr == as->root) { return as; }