Re: [libvirt] [PATCH v2 7/8] qemu: Implement VIR_DOMAIN_MIGRATE_MAX_SPEED_POSTCOPY flag
On 2/7/19 10:11 AM, Jiri Denemark wrote:
This flag tells virDomainMigrateSetMaxSpeed and
virDomainMigrateGetMaxSpeed APIs to work on post-copy migration
bandwidth.
Signed-off-by: Jiri Denemark <jdenemar(a)redhat.com>
---
Notes:
Version 2:
- if (postcopy) branch from qemuDomainMigrateGetMaxSpeed separated
into a helper function
[...]
+
+static int
+qemuDomainMigrationGetPostcopyBandwidth(virQEMUDriverPtr driver,
+ virDomainObjPtr vm,
+ unsigned long *bandwidth)
+{
+ VIR_AUTOPTR(qemuMigrationParams) migParams = NULL;
+ unsigned long long bw;
+ int rc;
+ int ret = -1;
+
+ if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_QUERY) < 0)
+ return -1;
+
+ if (virDomainObjCheckActive(vm) < 0)
+ goto cleanup;
+
+ if (qemuMigrationParamsFetch(driver, vm, QEMU_ASYNC_JOB_NONE,
+ &migParams) < 0)
+ goto cleanup;
+
+ if ((rc = qemuMigrationParamsGetULL(migParams,
+ QEMU_MIGRATION_PARAM_MAX_POSTCOPY_BANDWIDTH,
+ &bw)) < 0)
+ goto cleanup;
+
+ if (rc == 1) {
+ virReportError(VIR_ERR_OPERATION_INVALID, "%s",
+ _("querying maximum post-copy migration speed is "
+ "not supported by QEMU binary"));
+ goto cleanup;
+ }
+
+ /* QEMU reports B/s while we use MiB/s */
+ bw /= 1024 * 1024;
+
+ if (bw > ULONG_MAX) {
FWIW: Coverity generates a complaint here:
1) Event result_independent_of_operands: "bw > 18446744073709551615ULL
/* 9223372036854775807L * 2UL + 1UL */" is always false regardless of
the values of its operands. This occurs as the logical operand of "if".
John
+ virReportError(VIR_ERR_OVERFLOW,
+ _("bandwidth %llu is greater than %lu which is the "
+ "maximum value supported by this API"),
+ bw, ULONG_MAX);
+ goto cleanup;
+ }
+
+ *bandwidth = bw;
+ ret = 0;
+
+ cleanup:
+ qemuDomainObjEndJob(driver, vm);
+ return ret;
+}
+
+
[...]