diff mbox series

[48/52] migration/rdma: Silence qemu_rdma_block_for_wrid()

Message ID 20230918144206.560120-49-armbru@redhat.com
State New
Headers show
Series migration/rdma: Error handling fixes | expand

Commit Message

Markus Armbruster Sept. 18, 2023, 2:42 p.m. UTC 
Functions that use an Error **errp parameter to return errors should
not also report them to the user, because reporting is the caller's
job.  When the caller does, the error is reported twice.  When it
doesn't (because it recovered from the error), there is no error to
report, i.e. the report is bogus.

qemu_rdma_post_send_control(), qemu_rdma_exchange_get_response(), and
qemu_rdma_write_one() violate this principle: they call
error_report(), fprintf(stderr, ...), and perror() via
qemu_rdma_block_for_wrid(), qemu_rdma_poll(), and
qemu_rdma_wait_comp_channel().  I elected not to investigate how
callers handle the error, i.e. precise impact is not known.

Clean this up by dropping the error reporting from qemu_rdma_poll(),
qemu_rdma_wait_comp_channel(), and qemu_rdma_block_for_wrid().  I
believe the callers' error reports suffice.  If they don't, we need to
convert to Error instead.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
---
 migration/rdma.c | 11 -----------
 1 file changed, 11 deletions(-)

Comments

Li Zhijian Sept. 26, 2023, 6:17 a.m. UTC | #1 
On 18/09/2023 22:42, Markus Armbruster wrote:
> Functions that use an Error **errp parameter to return errors should
> not also report them to the user, because reporting is the caller's
> job.  When the caller does, the error is reported twice.  When it
> doesn't (because it recovered from the error), there is no error to
> report, i.e. the report is bogus.
> 
> qemu_rdma_post_send_control(), qemu_rdma_exchange_get_response(), and
> qemu_rdma_write_one() violate this principle: they call
> error_report(), fprintf(stderr, ...), and perror() via
> qemu_rdma_block_for_wrid(), qemu_rdma_poll(), and
> qemu_rdma_wait_comp_channel().  I elected not to investigate how
> callers handle the error, i.e. precise impact is not known.
> 
> Clean this up by dropping the error reporting from qemu_rdma_poll(),
> qemu_rdma_wait_comp_channel(), and qemu_rdma_block_for_wrid().  I
> believe the callers' error reports suffice.  If they don't, we need to
> convert to Error instead.
> 
> Signed-off-by: Markus Armbruster<armbru@redhat.com>

Reviewed-by: Li Zhijian <lizhijian@fujitsu.com>
diff mbox series

Patch

diff --git a/migration/rdma.c b/migration/rdma.c
index cbf5e6b9a8..99dccdeae5 100644
--- a/migration/rdma.c
+++ b/migration/rdma.c
@@ -1467,17 +1467,12 @@  static int qemu_rdma_poll(RDMAContext *rdma, struct ibv_cq *cq,
     }
 
     if (ret < 0) {
-        error_report("ibv_poll_cq failed");
         return -1;
     }
 
     wr_id = wc.wr_id & RDMA_WRID_TYPE_MASK;
 
     if (wc.status != IBV_WC_SUCCESS) {
-        fprintf(stderr, "ibv_poll_cq wc.status=%d %s!\n",
-                        wc.status, ibv_wc_status_str(wc.status));
-        fprintf(stderr, "ibv_poll_cq wrid=%" PRIu64 "!\n", wr_id);
-
         return -1;
     }
 
@@ -1561,16 +1556,12 @@  static int qemu_rdma_wait_comp_channel(RDMAContext *rdma,
                 if (pfds[1].revents) {
                     ret = rdma_get_cm_event(rdma->channel, &cm_event);
                     if (ret < 0) {
-                        error_report("failed to get cm event while wait "
-                                     "completion channel");
                         return -1;
                     }
 
                     if (cm_event->event == RDMA_CM_EVENT_DISCONNECTED ||
                         cm_event->event == RDMA_CM_EVENT_DEVICE_REMOVAL) {
                         rdma_ack_cm_event(cm_event);
-                        error_report("receive cm event while wait comp channel,"
-                                     "cm event is %d", cm_event->event);
                         return -1;
                     }
                     rdma_ack_cm_event(cm_event);
@@ -1583,7 +1574,6 @@  static int qemu_rdma_wait_comp_channel(RDMAContext *rdma,
             default: /* Error of some type -
                       * I don't trust errno from qemu_poll_ns
                      */
-                error_report("%s: poll failed", __func__);
                 return -1;
             }
 
@@ -1667,7 +1657,6 @@  static int qemu_rdma_block_for_wrid(RDMAContext *rdma,
 
         ret = ibv_get_cq_event(ch, &cq, &cq_ctx);
         if (ret < 0) {
-            perror("ibv_get_cq_event");
             goto err_block_for_wrid;
         }