| Message ID | 1528212489-19137-10-git-send-email-lidongchen@tencent.com |
|---|---|
| State | New |
| Headers | show |
| Series | Enable postcopy RDMA live migration | expand |
* Lidong Chen (jemmy858585@gmail.com) wrote: > If the peer qemu is crashed, the qemu_rdma_wait_comp_channel function > maybe loop forever. so we should also poll the cm event fd, and when > receive RDMA_CM_EVENT_DISCONNECTED and RDMA_CM_EVENT_DEVICE_REMOVAL, > we consider some error happened. > > Signed-off-by: Lidong Chen <lidongchen@tencent.com> Was there a reply which explained/pointed to docs for cm_event? Or a Review-by from one of the Infiniband people would be fine. Dave > --- > migration/rdma.c | 33 ++++++++++++++++++++++++++++++--- > 1 file changed, 30 insertions(+), 3 deletions(-) > > diff --git a/migration/rdma.c b/migration/rdma.c > index f12e8d5..bb6989e 100644 > --- a/migration/rdma.c > +++ b/migration/rdma.c > @@ -1489,6 +1489,9 @@ static uint64_t qemu_rdma_poll(RDMAContext *rdma, uint64_t *wr_id_out, > */ > static int qemu_rdma_wait_comp_channel(RDMAContext *rdma) > { > + struct rdma_cm_event *cm_event; > + int ret = -1; > + > /* > * Coroutine doesn't start until migration_fd_process_incoming() > * so don't yield unless we know we're running inside of a coroutine. > @@ -1505,13 +1508,37 @@ static int qemu_rdma_wait_comp_channel(RDMAContext *rdma) > * without hanging forever. > */ > while (!rdma->error_state && !rdma->received_error) { > - GPollFD pfds[1]; > + GPollFD pfds[2]; > pfds[0].fd = rdma->comp_channel->fd; > pfds[0].events = G_IO_IN | G_IO_HUP | G_IO_ERR; > + pfds[0].revents = 0; > + > + pfds[1].fd = rdma->channel->fd; > + pfds[1].events = G_IO_IN | G_IO_HUP | G_IO_ERR; > + pfds[1].revents = 0; > + > /* 0.1s timeout, should be fine for a 'cancel' */ > - switch (qemu_poll_ns(pfds, 1, 100 * 1000 * 1000)) { > + switch (qemu_poll_ns(pfds, 2, 100 * 1000 * 1000)) { > + case 2: > case 1: /* fd active */ > - return 0; > + if (pfds[0].revents) { > + return 0; > + } > + > + if (pfds[1].revents) { > + ret = rdma_get_cm_event(rdma->channel, &cm_event); > + if (!ret) { > + rdma_ack_cm_event(cm_event); > + } > + > + error_report("receive cm event while wait comp channel," > + "cm event is %d", cm_event->event); > + if (cm_event->event == RDMA_CM_EVENT_DISCONNECTED || > + cm_event->event == RDMA_CM_EVENT_DEVICE_REMOVAL) { > + return -EPIPE; > + } > + } > + break; > > case 0: /* Timeout, go around again */ > break; > -- > 1.8.3.1 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
On Wed, Jun 13, 2018 at 10:24 PM, Dr. David Alan Gilbert <dgilbert@redhat.com> wrote: > * Lidong Chen (jemmy858585@gmail.com) wrote: >> If the peer qemu is crashed, the qemu_rdma_wait_comp_channel function >> maybe loop forever. so we should also poll the cm event fd, and when >> receive RDMA_CM_EVENT_DISCONNECTED and RDMA_CM_EVENT_DEVICE_REMOVAL, >> we consider some error happened. >> >> Signed-off-by: Lidong Chen <lidongchen@tencent.com> > > Was there a reply which explained/pointed to docs for cm_event? https://linux.die.net/man/3/rdma_get_cm_event > Or a Review-by from one of the Infiniband people would be fine. yes, I should add Gal Shachaf <galsha@mellanox.com>,Aviad Yehezkel <aviadye@mellanox.com> we are working together on RDMA live migration. Thanks. > > Dave > >> --- >> migration/rdma.c | 33 ++++++++++++++++++++++++++++++--- >> 1 file changed, 30 insertions(+), 3 deletions(-) >> >> diff --git a/migration/rdma.c b/migration/rdma.c >> index f12e8d5..bb6989e 100644 >> --- a/migration/rdma.c >> +++ b/migration/rdma.c >> @@ -1489,6 +1489,9 @@ static uint64_t qemu_rdma_poll(RDMAContext *rdma, uint64_t *wr_id_out, >> */ >> static int qemu_rdma_wait_comp_channel(RDMAContext *rdma) >> { >> + struct rdma_cm_event *cm_event; >> + int ret = -1; >> + >> /* >> * Coroutine doesn't start until migration_fd_process_incoming() >> * so don't yield unless we know we're running inside of a coroutine. >> @@ -1505,13 +1508,37 @@ static int qemu_rdma_wait_comp_channel(RDMAContext *rdma) >> * without hanging forever. >> */ >> while (!rdma->error_state && !rdma->received_error) { >> - GPollFD pfds[1]; >> + GPollFD pfds[2]; >> pfds[0].fd = rdma->comp_channel->fd; >> pfds[0].events = G_IO_IN | G_IO_HUP | G_IO_ERR; >> + pfds[0].revents = 0; >> + >> + pfds[1].fd = rdma->channel->fd; >> + pfds[1].events = G_IO_IN | G_IO_HUP | G_IO_ERR; >> + pfds[1].revents = 0; >> + >> /* 0.1s timeout, should be fine for a 'cancel' */ >> - switch (qemu_poll_ns(pfds, 1, 100 * 1000 * 1000)) { >> + switch (qemu_poll_ns(pfds, 2, 100 * 1000 * 1000)) { >> + case 2: >> case 1: /* fd active */ >> - return 0; >> + if (pfds[0].revents) { >> + return 0; >> + } >> + >> + if (pfds[1].revents) { >> + ret = rdma_get_cm_event(rdma->channel, &cm_event); >> + if (!ret) { >> + rdma_ack_cm_event(cm_event); >> + } >> + >> + error_report("receive cm event while wait comp channel," >> + "cm event is %d", cm_event->event); >> + if (cm_event->event == RDMA_CM_EVENT_DISCONNECTED || >> + cm_event->event == RDMA_CM_EVENT_DEVICE_REMOVAL) { >> + return -EPIPE; >> + } >> + } >> + break; >> >> case 0: /* Timeout, go around again */ >> break; >> -- >> 1.8.3.1 >> > -- > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
diff --git a/migration/rdma.c b/migration/rdma.c index f12e8d5..bb6989e 100644 --- a/migration/rdma.c +++ b/migration/rdma.c @@ -1489,6 +1489,9 @@ static uint64_t qemu_rdma_poll(RDMAContext *rdma, uint64_t *wr_id_out, */ static int qemu_rdma_wait_comp_channel(RDMAContext *rdma) { + struct rdma_cm_event *cm_event; + int ret = -1; + /* * Coroutine doesn't start until migration_fd_process_incoming() * so don't yield unless we know we're running inside of a coroutine. @@ -1505,13 +1508,37 @@ static int qemu_rdma_wait_comp_channel(RDMAContext *rdma) * without hanging forever. */ while (!rdma->error_state && !rdma->received_error) { - GPollFD pfds[1]; + GPollFD pfds[2]; pfds[0].fd = rdma->comp_channel->fd; pfds[0].events = G_IO_IN | G_IO_HUP | G_IO_ERR; + pfds[0].revents = 0; + + pfds[1].fd = rdma->channel->fd; + pfds[1].events = G_IO_IN | G_IO_HUP | G_IO_ERR; + pfds[1].revents = 0; + /* 0.1s timeout, should be fine for a 'cancel' */ - switch (qemu_poll_ns(pfds, 1, 100 * 1000 * 1000)) { + switch (qemu_poll_ns(pfds, 2, 100 * 1000 * 1000)) { + case 2: case 1: /* fd active */ - return 0; + if (pfds[0].revents) { + return 0; + } + + if (pfds[1].revents) { + ret = rdma_get_cm_event(rdma->channel, &cm_event); + if (!ret) { + rdma_ack_cm_event(cm_event); + } + + error_report("receive cm event while wait comp channel," + "cm event is %d", cm_event->event); + if (cm_event->event == RDMA_CM_EVENT_DISCONNECTED || + cm_event->event == RDMA_CM_EVENT_DEVICE_REMOVAL) { + return -EPIPE; + } + } + break; case 0: /* Timeout, go around again */ break;
If the peer qemu is crashed, the qemu_rdma_wait_comp_channel function maybe loop forever. so we should also poll the cm event fd, and when receive RDMA_CM_EVENT_DISCONNECTED and RDMA_CM_EVENT_DEVICE_REMOVAL, we consider some error happened. Signed-off-by: Lidong Chen <lidongchen@tencent.com> --- migration/rdma.c | 33 ++++++++++++++++++++++++++++++--- 1 file changed, 30 insertions(+), 3 deletions(-)