commit de1aa35f8dbb9666360648148e57ceacb1bf8b5b
author Markus Armbruster <armbru@redhat.com> Thu Sep 28 15:20:04 2023 +0200
committer Juan Quintela <quintela@redhat.com> Wed Oct 11 11:17:04 2023 +0200
tree 47eca8ef80314dd1e29658eccd2b9feeb0b791b6
parent 3765ec1f432065e451fe86c54b93fc19a49f0cf4

migration/rdma: Convert qemu_rdma_reg_whole_ram_blocks() to Error

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_exchange_send() violates this principle: it calls
error_report() via callback qemu_rdma_reg_whole_ram_blocks().  I
elected not to investigate how callers handle the error, i.e. precise
impact is not known.

Clean this up by converting the callback to Error.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Li Zhijian <lizhijian@fujitsu.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20230928132019.2544702-39-armbru@redhat.com>

migration/rdma.c

diff --git a/migration/rdma.c b/migration/rdma.c
index 87f2e61..1899320 100644
--- a/migration/rdma.c
+++ b/migration/rdma.c
@@ -518,7 +518,8 @@
 static int qemu_rdma_exchange_send(RDMAContext *rdma, RDMAControlHeader *head,
                                    uint8_t *data, RDMAControlHeader *resp,
                                    int *resp_idx,
-                                   int (*callback)(RDMAContext *rdma),
+                                   int (*callback)(RDMAContext *rdma,
+                                                   Error **errp),
                                    Error **errp);
 
 static inline uint64_t ram_chunk_index(const uint8_t *start,
@@ -1177,7 +1178,7 @@
 #endif
 }
 
-static int qemu_rdma_reg_whole_ram_blocks(RDMAContext *rdma)
+static int qemu_rdma_reg_whole_ram_blocks(RDMAContext *rdma, Error **errp)
 {
     int i;
     RDMALocalBlocks *local = &rdma->local_ram_blocks;
@@ -1217,16 +1218,16 @@
         }
 
         if (!local->block[i].mr) {
-            perror("Failed to register local dest ram block!");
-            break;
+            error_setg_errno(errp, errno,
+                             "Failed to register local dest ram block!");
+            goto err;
         }
         rdma->total_registrations++;
     }
 
-    if (i >= local->nb_blocks) {
-        return 0;
-    }
+    return 0;
 
+err:
     for (i--; i >= 0; i--) {
         ibv_dereg_mr(local->block[i].mr);
         local->block[i].mr = NULL;
@@ -1899,7 +1900,8 @@
 static int qemu_rdma_exchange_send(RDMAContext *rdma, RDMAControlHeader *head,
                                    uint8_t *data, RDMAControlHeader *resp,
                                    int *resp_idx,
-                                   int (*callback)(RDMAContext *rdma),
+                                   int (*callback)(RDMAContext *rdma,
+                                                   Error **errp),
                                    Error **errp)
 {
     int ret;
@@ -1956,9 +1958,8 @@
     if (resp) {
         if (callback) {
             trace_qemu_rdma_exchange_send_issue_callback();
-            ret = callback(rdma);
+            ret = callback(rdma, errp);
             if (ret < 0) {
-                error_setg(errp, "FIXME temporary error message");
                 return -1;
             }
         }
@@ -3671,10 +3672,9 @@
             }
 
             if (rdma->pin_all) {
-                ret = qemu_rdma_reg_whole_ram_blocks(rdma);
+                ret = qemu_rdma_reg_whole_ram_blocks(rdma, &err);
                 if (ret < 0) {
-                    error_report("rdma migration: error dest "
-                                    "registering ram blocks");
+                    error_report_err(err);
                     goto err;
                 }
             }