implement a function similar to qemuMigrationSrcToFile that migrates to multiple files using QEMU multifd, and use it for VIR_DOMAIN_SAVE_PARALLEL saves.
Signed-off-by: Claudio Fontana <cfont...@suse.de> --- src/qemu/qemu_migration.c | 131 +++++++++++++++++++++++++------------- src/qemu/qemu_migration.h | 7 ++ src/qemu/qemu_saveimage.c | 8 ++- 3 files changed, 98 insertions(+), 48 deletions(-) diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c index f130ccbe26..fa6cddcc59 100644 --- a/src/qemu/qemu_migration.c +++ b/src/qemu/qemu_migration.c @@ -5875,13 +5875,14 @@ qemuMigrationDstFinish(virQEMUDriver *driver, return dom; } - /* Helper function called while vm is active. */ -int -qemuMigrationSrcToFile(virQEMUDriver *driver, virDomainObj *vm, - int fd, - virCommand *compressor, - virDomainAsyncJob asyncJob) +static int +qemuMigrationSrcToFileAux(virQEMUDriver *driver, virDomainObj *vm, + int fd, + virCommand *compressor, + virDomainAsyncJob asyncJob, + const char *sun_path, + int nchannels) { qemuDomainObjPrivate *priv = vm->privateData; bool bwParam = virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_MIGRATION_PARAM_BANDWIDTH); @@ -5892,24 +5893,26 @@ qemuMigrationSrcToFile(virQEMUDriver *driver, virDomainObj *vm, char *errbuf = NULL; virErrorPtr orig_err = NULL; g_autoptr(qemuMigrationParams) migParams = NULL; + bool needParams = (bwParam || sun_path); + if (sun_path && !virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_MIGRATE_MULTIFD)) { + virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s", + _("QEMU does not seem to support multifd migration, required for parallel migration to files")); + return -1; + } if (qemuMigrationSetDBusVMState(driver, vm) < 0) return -1; /* Increase migration bandwidth to unlimited since target is a file. * Failure to change migration speed is not fatal. */ - if (bwParam) { - if (!(migParams = qemuMigrationParamsNew())) - return -1; + if (needParams && !((migParams = qemuMigrationParamsNew()))) + return -1; + if (bwParam) { if (qemuMigrationParamsSetULL(migParams, QEMU_MIGRATION_PARAM_MAX_BANDWIDTH, QEMU_DOMAIN_MIG_BANDWIDTH_MAX * 1024 * 1024) < 0) return -1; - - if (qemuMigrationParamsApply(driver, vm, asyncJob, migParams) < 0) - return -1; - priv->migMaxBandwidth = QEMU_DOMAIN_MIG_BANDWIDTH_MAX; } else { if (qemuDomainObjEnterMonitorAsync(driver, vm, asyncJob) == 0) { @@ -5920,6 +5923,17 @@ qemuMigrationSrcToFile(virQEMUDriver *driver, virDomainObj *vm, } } + if (sun_path) { + qemuMigrationParamsSetCap(migParams, QEMU_MIGRATION_CAP_MULTIFD); + if (qemuMigrationParamsSetInt(migParams, + QEMU_MIGRATION_PARAM_MULTIFD_CHANNELS, + nchannels) < 0) + return -1; + } + + if (needParams && qemuMigrationParamsApply(driver, vm, asyncJob, migParams) < 0) + return -1; + if (!virDomainObjIsActive(vm)) { virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("guest unexpectedly quit")); @@ -5927,45 +5941,53 @@ qemuMigrationSrcToFile(virQEMUDriver *driver, virDomainObj *vm, return -1; } - if (compressor && virPipe(pipeFD) < 0) + if (!sun_path && compressor && virPipe(pipeFD) < 0) return -1; - /* All right! We can use fd migration, which means that qemu - * doesn't have to open() the file, so while we still have to - * grant SELinux access, we can do it on fd and avoid cleanup - * later, as well as skip futzing with cgroup. */ - if (qemuSecuritySetImageFDLabel(driver->securityManager, vm->def, - compressor ? pipeFD[1] : fd) < 0) - goto cleanup; - if (qemuDomainObjEnterMonitorAsync(driver, vm, asyncJob) < 0) goto cleanup; - if (!compressor) { - rc = qemuMonitorMigrateToFd(priv->mon, - QEMU_MONITOR_MIGRATE_BACKGROUND, - fd); + if (sun_path) { + rc = qemuMonitorMigrateToSocket(priv->mon, + QEMU_MONITOR_MIGRATE_BACKGROUND, + sun_path); } else { - virCommandSetInputFD(compressor, pipeFD[0]); - virCommandSetOutputFD(compressor, &fd); - virCommandSetErrorBuffer(compressor, &errbuf); - virCommandDoAsyncIO(compressor); - if (virSetCloseExec(pipeFD[1]) < 0) { - virReportSystemError(errno, "%s", - _("Unable to set cloexec flag")); - qemuDomainObjExitMonitor(vm); - goto cleanup; - } - if (virCommandRunAsync(compressor, NULL) < 0) { - qemuDomainObjExitMonitor(vm); + /* + * All right! We can use fd migration, which means that qemu + * doesn't have to open() the file, so while we still have to + * grant SELinux access, we can do it on fd and avoid cleanup + * later, as well as skip futzing with cgroup. + */ + if (qemuSecuritySetImageFDLabel(driver->securityManager, vm->def, + compressor ? pipeFD[1] : fd) < 0) goto cleanup; + + if (!compressor) { + rc = qemuMonitorMigrateToFd(priv->mon, + QEMU_MONITOR_MIGRATE_BACKGROUND, + fd); + } else { + virCommandSetInputFD(compressor, pipeFD[0]); + virCommandSetOutputFD(compressor, &fd); + virCommandSetErrorBuffer(compressor, &errbuf); + virCommandDoAsyncIO(compressor); + if (virSetCloseExec(pipeFD[1]) < 0) { + virReportSystemError(errno, "%s", + _("Unable to set cloexec flag")); + qemuDomainObjExitMonitor(vm); + goto cleanup; + } + if (virCommandRunAsync(compressor, NULL) < 0) { + qemuDomainObjExitMonitor(vm); + goto cleanup; + } + rc = qemuMonitorMigrateToFd(priv->mon, + QEMU_MONITOR_MIGRATE_BACKGROUND, + pipeFD[1]); + if (VIR_CLOSE(pipeFD[0]) < 0 || + VIR_CLOSE(pipeFD[1]) < 0) + VIR_WARN("failed to close intermediate pipe"); } - rc = qemuMonitorMigrateToFd(priv->mon, - QEMU_MONITOR_MIGRATE_BACKGROUND, - pipeFD[1]); - if (VIR_CLOSE(pipeFD[0]) < 0 || - VIR_CLOSE(pipeFD[1]) < 0) - VIR_WARN("failed to close intermediate pipe"); } qemuDomainObjExitMonitor(vm); if (rc < 0) @@ -5986,7 +6008,7 @@ qemuMigrationSrcToFile(virQEMUDriver *driver, virDomainObj *vm, goto cleanup; } - if (compressor && virCommandWait(compressor, NULL) < 0) + if (!sun_path && compressor && virCommandWait(compressor, NULL) < 0) goto cleanup; qemuDomainEventEmitJobCompleted(driver, vm); @@ -6025,6 +6047,25 @@ qemuMigrationSrcToFile(virQEMUDriver *driver, virDomainObj *vm, return ret; } +int +qemuMigrationSrcToFile(virQEMUDriver *driver, virDomainObj *vm, + int fd, + virCommand *compressor, + virDomainAsyncJob asyncJob) +{ + return qemuMigrationSrcToFileAux(driver, vm, fd, compressor, + asyncJob, NULL, -1); +} + +int +qemuMigrationSrcToFilesMultiFd(virQEMUDriver *driver, virDomainObj *vm, + virDomainAsyncJob asyncJob, + const char *sun_path, + int nchannels) +{ + return qemuMigrationSrcToFileAux(driver, vm, -1, NULL, + asyncJob, sun_path, nchannels); +} int qemuMigrationSrcCancel(virQEMUDriver *driver, diff --git a/src/qemu/qemu_migration.h b/src/qemu/qemu_migration.h index a8afa66119..ddc8e65489 100644 --- a/src/qemu/qemu_migration.h +++ b/src/qemu/qemu_migration.h @@ -213,6 +213,13 @@ qemuMigrationSrcToFile(virQEMUDriver *driver, virDomainAsyncJob asyncJob) ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) G_GNUC_WARN_UNUSED_RESULT; +int +qemuMigrationSrcToFilesMultiFd(virQEMUDriver *driver, virDomainObj *vm, + virDomainAsyncJob asyncJob, + const char *sun_path, + int nchannels) + ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) G_GNUC_WARN_UNUSED_RESULT; + int qemuMigrationSrcCancel(virQEMUDriver *driver, virDomainObj *vm); diff --git a/src/qemu/qemu_saveimage.c b/src/qemu/qemu_saveimage.c index 7d8527596a..8abb919459 100644 --- a/src/qemu/qemu_saveimage.c +++ b/src/qemu/qemu_saveimage.c @@ -578,8 +578,11 @@ qemuSaveImageCreate(virQEMUDriver *driver, oflags |= O_DIRECT; } - if (virQEMUSaveFdInit(&saveFd, path, oflags, cfg, false) < 0) + if (virQEMUSaveFdInit(&saveFd, path, oflags, cfg, flags & VIR_DOMAIN_SAVE_PARALLEL) < 0) goto cleanup; + if (nconn > 0) { + data->header.multifd_channels = nconn; + } if (qemuSecuritySetImageFDLabel(driver->securityManager, vm->def, saveFd.fd) < 0) goto cleanup; if (virQEMUSaveDataWrite(data, saveFd.fd, saveFd.path) < 0) @@ -610,8 +613,7 @@ qemuSaveImageCreate(virQEMUDriver *driver, goto cleanup; if (chown(sun_path, cfg->user, cfg->group) < 0) goto cleanup; - /* still using single fd migration for now */ - if (qemuMigrationSrcToFile(driver, vm, saveFd.fd, compressor, asyncJob) < 0) + if (qemuMigrationSrcToFilesMultiFd(driver, vm, asyncJob, sun_path, nconn) < 0) goto cleanup; } else { /* Perform non-parallel migration to file */ -- 2.26.2