From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33519) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fEAfV-0007Kf-Ma for qemu-devel@nongnu.org; Thu, 03 May 2018 05:36:57 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fEAfS-0004Pl-H3 for qemu-devel@nongnu.org; Thu, 03 May 2018 05:36:53 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:51532 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fEAfS-0004PP-D2 for qemu-devel@nongnu.org; Thu, 03 May 2018 05:36:50 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 02AF876FBA for ; Thu, 3 May 2018 09:36:50 +0000 (UTC) Date: Thu, 3 May 2018 10:36:46 +0100 From: "Dr. David Alan Gilbert" Message-ID: <20180503093646.GA2660@work-vm> References: <20180425112723.1111-1-quintela@redhat.com> <20180425112723.1111-15-quintela@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180425112723.1111-15-quintela@redhat.com> Subject: Re: [Qemu-devel] [PATCH v12 14/21] migration: Multifd channels always wait on the sem List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Juan Quintela Cc: qemu-devel@nongnu.org, lvivier@redhat.com, peterx@redhat.com * Juan Quintela (quintela@redhat.com) wrote: > Either for quit, sync or packet, we first wake them. > > Signed-off-by: Juan Quintela > --- > migration/ram.c | 13 +++++++++++-- > 1 file changed, 11 insertions(+), 2 deletions(-) > > diff --git a/migration/ram.c b/migration/ram.c > index 0f1340b4e3..21b448c4ed 100644 > --- a/migration/ram.c > +++ b/migration/ram.c > @@ -754,6 +754,7 @@ static void *multifd_send_thread(void *opaque) > p->num_packets = 1; > > while (true) { > + qemu_sem_wait(&p->sem); > qemu_mutex_lock(&p->mutex); > multifd_send_fill_packet(p); > if (p->quit) { > @@ -761,7 +762,9 @@ static void *multifd_send_thread(void *opaque) > break; > } > qemu_mutex_unlock(&p->mutex); > - qemu_sem_wait(&p->sem); > + /* this is impossible */ > + error_setg(&local_err, "multifd_send_thread: Unknown command"); > + break; This error disappears in a later patch saying that you can have spurious wakeups. > } > > out: > @@ -905,6 +908,7 @@ static void *multifd_recv_thread(void *opaque) > trace_multifd_recv_thread_start(p->id); > > while (true) { > + qemu_sem_wait(&p->sem); > qemu_mutex_lock(&p->mutex); All this stuff seems to change again in later patches. Is there stuff here that can be flattened into the other patches? Dave > if (false) { > /* ToDo: Packet reception goes here */ > @@ -919,9 +923,14 @@ static void *multifd_recv_thread(void *opaque) > break; > } > qemu_mutex_unlock(&p->mutex); > - qemu_sem_wait(&p->sem); > + /* this is impossible */ > + error_setg(&local_err, "multifd_recv_thread: Unknown command"); > + break; > } > > + if (local_err) { > + multifd_recv_terminate_threads(local_err); > + } > qemu_mutex_lock(&p->mutex); > p->running = false; > qemu_mutex_unlock(&p->mutex); > -- > 2.17.0 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK