[PULL 05/17] migration/multifd: Stop checking p->quit in multifd_send_thread

Juan Quintela posted 17 patches 1 year, 1 month ago
Maintainers: Stefan Berger <stefanb@linux.vnet.ibm.com>, Stefan Hajnoczi <stefanha@redhat.com>, "Denis V. Lunev" <den@openvz.org>, Kevin Wolf <kwolf@redhat.com>, Hanna Reitz <hreitz@redhat.com>, Stefan Weil <sw@weilnetz.de>, Jeff Cody <codyprime@gmail.com>, Fam Zheng <fam@euphon.net>, "Marc-André Lureau" <marcandre.lureau@redhat.com>, Greg Kurz <groug@kaod.org>, Christian Schoenebeck <qemu_oss@crudebyte.com>, "Michael S. Tsirkin" <mst@redhat.com>, Gerd Hoffmann <kraxel@redhat.com>, Peter Maydell <peter.maydell@linaro.org>, Jason Wang <jasowang@redhat.com>, Nicholas Piggin <npiggin@gmail.com>, Daniel Henrique Barboza <danielhb413@gmail.com>, "Cédric Le Goater" <clg@kaod.org>, David Gibson <david@gibson.dropbear.id.au>, Harsh Prateek Bora <harshpb@linux.ibm.com>, Elena Ufimtseva <elena.ufimtseva@oracle.com>, Jagannathan Raman <jag.raman@oracle.com>, Thomas Huth <thuth@redhat.com>, Richard Henderson <richard.henderson@linaro.org>, David Hildenbrand <david@redhat.com>, Ilya Leoshkevich <iii@linux.ibm.com>, Halil Pasic <pasic@linux.ibm.com>, Christian Borntraeger <borntraeger@linux.ibm.com>, Eric Farman <farman@linux.ibm.com>, Paolo Bonzini <pbonzini@redhat.com>, Alex Williamson <alex.williamson@redhat.com>, Juan Quintela <quintela@redhat.com>, Peter Xu <peterx@redhat.com>, Fabiano Rosas <farosas@suse.de>, Leonardo Bras <leobras@redhat.com>, Marcelo Tosatti <mtosatti@redhat.com>, Reinoud Zandijk <reinoud@netbsd.org>, Sunil Muthuswamy <sunilmut@microsoft.com>, Laurent Vivier <lvivier@redhat.com>
[PULL 05/17] migration/multifd: Stop checking p->quit in multifd_send_thread
Posted by Juan Quintela 1 year, 1 month ago
From: Fabiano Rosas <farosas@suse.de>

We don't need to check p->quit in the multifd_send_thread() because it
is shadowed by the 'exiting' flag. Ever since that flag was added
p->quit became obsolete as a way to stop the thread.

Since p->quit is set at multifd_send_terminate_threads() under the
p->mutex lock, the thread will only see it once it loops, so 'exiting'
will always be seen first.

Note that setting p->quit at multifd_send_terminate_threads() still
makes sense because we need a way to inform multifd_send_pages() that
the channel has stopped.

Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231012140651.13122-3-farosas@suse.de>
---
 migration/multifd.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/migration/multifd.c b/migration/multifd.c
index 1fe53d3b98..e2a45c667a 100644
--- a/migration/multifd.c
+++ b/migration/multifd.c
@@ -743,9 +743,6 @@ static void *multifd_send_thread(void *opaque)
             if (flags & MULTIFD_FLAG_SYNC) {
                 qemu_sem_post(&p->sem_sync);
             }
-        } else if (p->quit) {
-            qemu_mutex_unlock(&p->mutex);
-            break;
         } else {
             qemu_mutex_unlock(&p->mutex);
             /* sometimes there are spurious wakeups */
-- 
2.41.0