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bh=E5BznSsUeQgE8jqC5Fqg/VQQUrmZ60X5UizbN/zWa8g=; b=eTDiCD+fuLzqFcCoLief1vefwzY6ThJsGNMmCprxO5hSeMhuffK93isjhU1+dZFX2K6YSz Q84ngcYzsENczEy6XUuJq2n4REF1zx27gJmcsZtCw2QEcJV4EE88SZnEfhN4cPwv2h+Tfl rFYQOiGvQHshKwSJiK6Iw5eSBEjm7S8= X-MC-Unique: s4Bcl2GHP66-LulmabqxAg-1 From: peterx@redhat.com To: qemu-devel@nongnu.org Cc: Bryan Zhang , Prasad Pandit , Fabiano Rosas , peterx@redhat.com, Yuan Liu , Avihai Horon , Hao Xiang Subject: [PATCH 14/14] migration/multifd: Forbid spurious wakeups Date: Wed, 31 Jan 2024 18:31:11 +0800 Message-ID: <20240131103111.306523-15-peterx@redhat.com> In-Reply-To: <20240131103111.306523-1-peterx@redhat.com> References: <20240131103111.306523-1-peterx@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.5 Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.133.124; envelope-from=peterx@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -33 X-Spam_score: -3.4 X-Spam_bar: --- X-Spam_report: (-3.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.292, 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_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @redhat.com) X-ZM-MESSAGEID: 1706697204874100003 Content-Type: text/plain; charset="utf-8" From: Peter Xu Now multifd's logic is designed to have no spurious wakeup. I still remember a talk to Juan and he seems to agree we should drop it now, and if my memory was right it was there because multifd used to hit that when still debugging. Let's drop it and see what can explode; as long as it's not reaching soft-freeze. Signed-off-by: Peter Xu Reviewed-by: Fabiano Rosas --- migration/multifd.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/migration/multifd.c b/migration/multifd.c index 0f22646f95..bd0e3ea1a5 100644 --- a/migration/multifd.c +++ b/migration/multifd.c @@ -766,9 +766,6 @@ static void *multifd_send_thread(void *opaque) p->pending_sync =3D false; qemu_mutex_unlock(&p->mutex); qemu_sem_post(&p->sem_sync); - } else { - qemu_mutex_unlock(&p->mutex); - /* sometimes there are spurious wakeups */ } } =20 --=20 2.43.0