| Message ID | 20230804093053.5037-1-wei.w.wang@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] migration: refactor migration_completion | expand |
On Fri, Aug 04, 2023 at 05:30:53PM +0800, Wei Wang wrote: > Current migration_completion function is a bit long. Refactor the long > implementation into different subfunctions: > - migration_completion_precopy: completion code related to precopy > - migration_completion_postcopy: completion code related to postcopy > - close_return_path_on_source: rp thread related cleanup on migration > completion. It is named to match with open_return_path_on_source. > > This improves readability and is easier for future updates (e.g. add new > subfunctions when completion code related to new features are needed). No > functional changes intended. > > Signed-off-by: Wei Wang <wei.w.wang@intel.com> Reviewed-by: Peter Xu <peterx@redhat.com>
On Fri, Aug 04, 2023 at 05:30:53PM +0800, Wei Wang <wei.w.wang@intel.com> wrote: > Current migration_completion function is a bit long. Refactor the long > implementation into different subfunctions: > - migration_completion_precopy: completion code related to precopy > - migration_completion_postcopy: completion code related to postcopy > - close_return_path_on_source: rp thread related cleanup on migration > completion. It is named to match with open_return_path_on_source. > > This improves readability and is easier for future updates (e.g. add new > subfunctions when completion code related to new features are needed). No > functional changes intended. > > Signed-off-by: Wei Wang <wei.w.wang@intel.com> > --- > Changelog: > - Merge await_return_path_close_on_source into > close_return_path_on_source as the later basically just calls the > previous; > - make migration_completion_postcopy "void" as it doesn't return a > value. Reviewed-by: Isaku Yamahata <isaku.yamahata@intel.com>
On Friday, August 4, 2023 9:37 PM, Peter Xu wrote: Fri, Aug 04, 2023 at 05:30:53PM +0800, Wei Wang wrote: > > Current migration_completion function is a bit long. Refactor the long > > implementation into different subfunctions: > > - migration_completion_precopy: completion code related to precopy > > - migration_completion_postcopy: completion code related to postcopy > > - close_return_path_on_source: rp thread related cleanup on migration > > completion. It is named to match with open_return_path_on_source. > > > > This improves readability and is easier for future updates (e.g. add > > new subfunctions when completion code related to new features are > > needed). No functional changes intended. > > > > Signed-off-by: Wei Wang <wei.w.wang@intel.com> > > Reviewed-by: Peter Xu <peterx@redhat.com> > Hi Juan, Do you think this refactoring would be good to merge or have any more comments? Thanks, Wei
Wei Wang <wei.w.wang@intel.com> wrote: > Current migration_completion function is a bit long. Refactor the long > implementation into different subfunctions: > - migration_completion_precopy: completion code related to precopy > - migration_completion_postcopy: completion code related to postcopy > - close_return_path_on_source: rp thread related cleanup on migration > completion. It is named to match with open_return_path_on_source. > > This improves readability and is easier for future updates (e.g. add new > subfunctions when completion code related to new features are needed). No > functional changes intended. > > Signed-off-by: Wei Wang <wei.w.wang@intel.com> Reviewed-by: Juan Quintela <quintela@redhat.com> queued.
Wei Wang <wei.w.wang@intel.com> wrote: > Current migration_completion function is a bit long. Refactor the long > implementation into different subfunctions: > - migration_completion_precopy: completion code related to precopy > - migration_completion_postcopy: completion code related to postcopy > - close_return_path_on_source: rp thread related cleanup on migration > completion. It is named to match with open_return_path_on_source. > > This improves readability and is easier for future updates (e.g. add new > subfunctions when completion code related to new features are needed). No > functional changes intended. > > Signed-off-by: Wei Wang <wei.w.wang@intel.com> There was some conflict with: commit d50f5dc075cbb891bfe4a9378600a4871264468a Author: Fabiano Rosas <farosas@suse.de> Date: Mon Sep 18 14:28:20 2023 -0300 migration: Consolidate return path closing code (basically the traces and the rp_thread_created check were already on the tree). BTW, the diff is uglier than it needs to be. You can add to your global .gitconfig: [diff] algorithm = patience renames = true commit e2db83d6e73df7619de75093d1477a7f3c638847 Author: Wei Wang <wei.w.wang@intel.com> Date: Fri Aug 4 17:30:53 2023 +0800 migration: refactor migration_completion Current migration_completion function is a bit long. Refactor the long implementation into different subfunctions: - migration_completion_precopy: completion code related to precopy - migration_completion_postcopy: completion code related to postcopy - close_return_path_on_source: rp thread related cleanup on migration completion. It is named to match with open_return_path_on_source. This improves readability and is easier for future updates (e.g. add new subfunctions when completion code related to new features are needed). No functional changes intended. Signed-off-by: Wei Wang <wei.w.wang@intel.com> diff --git a/migration/migration.c b/migration/migration.c index 1c6c81ad49..99a06832f5 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -99,7 +99,7 @@ static int migration_maybe_pause(MigrationState *s, int *current_active_state, int new_state); static void migrate_fd_cancel(MigrationState *s); -static int await_return_path_close_on_source(MigrationState *s); +static int close_return_path_on_source(MigrationState *s); static bool migration_needs_multiple_sockets(void) { @@ -1191,7 +1191,7 @@ static void migrate_fd_cleanup(MigrationState *s) * We already cleaned up to_dst_file, so errors from the return * path might be due to that, ignore them. */ - await_return_path_close_on_source(s); + close_return_path_on_source(s); assert(!migration_is_active(s)); @@ -2049,8 +2049,7 @@ static int open_return_path_on_source(MigrationState *ms) return 0; } -/* Returns 0 if the RP was ok, otherwise there was an error on the RP */ -static int await_return_path_close_on_source(MigrationState *ms) +static int close_return_path_on_source(MigrationState *ms) { int ret; @@ -2317,6 +2316,87 @@ static int migration_maybe_pause(MigrationState *s, return s->state == new_state ? 0 : -EINVAL; } +static int migration_completion_precopy(MigrationState *s, + int *current_active_state) +{ + int ret; + + qemu_mutex_lock_iothread(); + s->downtime_start = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); + qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER, NULL); + + s->vm_old_state = runstate_get(); + global_state_store(); + + ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE); + trace_migration_completion_vm_stop(ret); + if (ret < 0) { + goto out_unlock; + } + + ret = migration_maybe_pause(s, current_active_state, + MIGRATION_STATUS_DEVICE); + if (ret < 0) { + goto out_unlock; + } + + /* + * Inactivate disks except in COLO, and track that we have done so in order + * to remember to reactivate them if migration fails or is cancelled. + */ + s->block_inactive = !migrate_colo(); + migration_rate_set(RATE_LIMIT_DISABLED); + ret = qemu_savevm_state_complete_precopy(s->to_dst_file, false, + s->block_inactive); +out_unlock: + qemu_mutex_unlock_iothread(); + return ret; +} + +static void migration_completion_postcopy(MigrationState *s) +{ + trace_migration_completion_postcopy_end(); + + qemu_mutex_lock_iothread(); + qemu_savevm_state_complete_postcopy(s->to_dst_file); + qemu_mutex_unlock_iothread(); + + /* + * Shutdown the postcopy fast path thread. This is only needed when dest + * QEMU binary is old (7.1/7.2). QEMU 8.0+ doesn't need this. + */ + if (migrate_postcopy_preempt() && s->preempt_pre_7_2) { + postcopy_preempt_shutdown_file(s); + } + + trace_migration_completion_postcopy_end_after_complete(); +} + +static void migration_completion_failed(MigrationState *s, + int current_active_state) +{ + if (s->block_inactive && (s->state == MIGRATION_STATUS_ACTIVE || + s->state == MIGRATION_STATUS_DEVICE)) { + /* + * If not doing postcopy, vm_start() will be called: let's + * regain control on images. + */ + Error *local_err = NULL; + + qemu_mutex_lock_iothread(); + bdrv_activate_all(&local_err); + if (local_err) { + error_report_err(local_err); + } else { + s->block_inactive = false; + } + qemu_mutex_unlock_iothread(); + } + + migrate_set_state(&s->state, current_active_state, + MIGRATION_STATUS_FAILED); +} + /** * migration_completion: Used by migration_thread when there's not much left. * The caller 'breaks' the loop when this returns. @@ -2325,62 +2405,22 @@ static int migration_maybe_pause(MigrationState *s, */ static void migration_completion(MigrationState *s) { - int ret; + int ret = 0; int current_active_state = s->state; if (s->state == MIGRATION_STATUS_ACTIVE) { - qemu_mutex_lock_iothread(); - s->downtime_start = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); - qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER, NULL); - - s->vm_old_state = runstate_get(); - global_state_store(); - - ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE); - trace_migration_completion_vm_stop(ret); - if (ret >= 0) { - ret = migration_maybe_pause(s, ¤t_active_state, - MIGRATION_STATUS_DEVICE); - } - if (ret >= 0) { - /* - * Inactivate disks except in COLO, and track that we - * have done so in order to remember to reactivate - * them if migration fails or is cancelled. - */ - s->block_inactive = !migrate_colo(); - migration_rate_set(RATE_LIMIT_DISABLED); - ret = qemu_savevm_state_complete_precopy(s->to_dst_file, false, - s->block_inactive); - } - - qemu_mutex_unlock_iothread(); - - if (ret < 0) { - goto fail; - } + ret = migration_completion_precopy(s, ¤t_active_state); } else if (s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) { - trace_migration_completion_postcopy_end(); - - qemu_mutex_lock_iothread(); - qemu_savevm_state_complete_postcopy(s->to_dst_file); - qemu_mutex_unlock_iothread(); - - /* - * Shutdown the postcopy fast path thread. This is only needed - * when dest QEMU binary is old (7.1/7.2). QEMU 8.0+ doesn't need - * this. - */ - if (migrate_postcopy_preempt() && s->preempt_pre_7_2) { - postcopy_preempt_shutdown_file(s); - } - - trace_migration_completion_postcopy_end_after_complete(); + migration_completion_postcopy(s); } else { + ret = -1; + } + + if (ret < 0) { goto fail; } - if (await_return_path_close_on_source(s)) { + if (close_return_path_on_source(s) < 0) { goto fail; } @@ -2401,26 +2441,7 @@ static void migration_completion(MigrationState *s) return; fail: - if (s->block_inactive && (s->state == MIGRATION_STATUS_ACTIVE || - s->state == MIGRATION_STATUS_DEVICE)) { - /* - * If not doing postcopy, vm_start() will be called: let's - * regain control on images. - */ - Error *local_err = NULL; - - qemu_mutex_lock_iothread(); - bdrv_activate_all(&local_err); - if (local_err) { - error_report_err(local_err); - } else { - s->block_inactive = false; - } - qemu_mutex_unlock_iothread(); - } - - migrate_set_state(&s->state, current_active_state, - MIGRATION_STATUS_FAILED); + migration_completion_failed(s, current_active_state); } /** @@ -2563,7 +2584,7 @@ static MigThrError postcopy_pause(MigrationState *s) * path and just wait for the thread to finish. It will be * re-created when we resume. */ - await_return_path_close_on_source(s); + close_return_path_on_source(s); migrate_set_state(&s->state, s->state, MIGRATION_STATUS_POSTCOPY_PAUSED);
On Wednesday, October 11, 2023 8:41 PM, Juan Quintela wrote: > Wei Wang <wei.w.wang@intel.com> wrote: > > Current migration_completion function is a bit long. Refactor the long > > implementation into different subfunctions: > > - migration_completion_precopy: completion code related to precopy > > - migration_completion_postcopy: completion code related to postcopy > > - close_return_path_on_source: rp thread related cleanup on migration > > completion. It is named to match with open_return_path_on_source. > > > > This improves readability and is easier for future updates (e.g. add > > new subfunctions when completion code related to new features are > > needed). No functional changes intended. > > > > Signed-off-by: Wei Wang <wei.w.wang@intel.com> > > There was some conflict with: > > commit d50f5dc075cbb891bfe4a9378600a4871264468a > Author: Fabiano Rosas <farosas@suse.de> > Date: Mon Sep 18 14:28:20 2023 -0300 > > migration: Consolidate return path closing code > > (basically the traces and the rp_thread_created check were already on the > tree). > > BTW, the diff is uglier than it needs to be. > > You can add to your global .gitconfig: > > [diff] > algorithm = patience > renames = true Yeah, this generates a nicer diff, thanks. I'll rebase and resend it.
"Wang, Wei W" <wei.w.wang@intel.com> wrote: > On Wednesday, October 11, 2023 8:41 PM, Juan Quintela wrote: >> Wei Wang <wei.w.wang@intel.com> wrote: >> > Current migration_completion function is a bit long. Refactor the long >> > implementation into different subfunctions: >> > - migration_completion_precopy: completion code related to precopy >> > - migration_completion_postcopy: completion code related to postcopy >> > - close_return_path_on_source: rp thread related cleanup on migration >> > completion. It is named to match with open_return_path_on_source. >> > >> > This improves readability and is easier for future updates (e.g. add >> > new subfunctions when completion code related to new features are >> > needed). No functional changes intended. >> > >> > Signed-off-by: Wei Wang <wei.w.wang@intel.com> >> >> There was some conflict with: >> >> commit d50f5dc075cbb891bfe4a9378600a4871264468a >> Author: Fabiano Rosas <farosas@suse.de> >> Date: Mon Sep 18 14:28:20 2023 -0300 >> >> migration: Consolidate return path closing code >> >> (basically the traces and the rp_thread_created check were already on the >> tree). >> >> BTW, the diff is uglier than it needs to be. >> >> You can add to your global .gitconfig: >> >> [diff] >> algorithm = patience >> renames = true > > Yeah, this generates a nicer diff, thanks. > I'll rebase and resend it. Already on the pull request. I have to fix the conflict, but it has the same changes that yours as far as I can see. Later, Juan.
On Thursday, October 12, 2023 4:32 AM, Juan Quintela wrote: > > Yeah, this generates a nicer diff, thanks. > > I'll rebase and resend it. > > Already on the pull request. > > I have to fix the conflict, but it has the same changes that yours as far as I can > see. Yes, just need to remove the conflict part, other changes seem to be the same as before.
On Wednesday, October 11, 2023 8:41 PM, Juan Quintela wrote: > Wei Wang <wei.w.wang@intel.com> wrote: > > Current migration_completion function is a bit long. Refactor the long > > implementation into different subfunctions: > > - migration_completion_precopy: completion code related to precopy > > - migration_completion_postcopy: completion code related to postcopy > > - close_return_path_on_source: rp thread related cleanup on migration > > completion. It is named to match with open_return_path_on_source. Btw, just a reminder that the above line related to close_return_path_on_source in the commit log needs to be removed as it's not added by the patch after solving the conflicts.
diff --git a/migration/migration.c b/migration/migration.c index 5528acb65e..f1c55d1148 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -2048,9 +2048,13 @@ static int open_return_path_on_source(MigrationState *ms, return 0; } -/* Returns 0 if the RP was ok, otherwise there was an error on the RP */ -static int await_return_path_close_on_source(MigrationState *ms) +static int close_return_path_on_source(MigrationState *ms) { + if (!ms->rp_state.rp_thread_created) { + return 0; + } + trace_migration_return_path_end_before(); + /* * If this is a normal exit then the destination will send a SHUT and the * rp_thread will exit, however if there's an error we need to cause @@ -2068,6 +2072,8 @@ static int await_return_path_close_on_source(MigrationState *ms) qemu_thread_join(&ms->rp_state.rp_thread); ms->rp_state.rp_thread_created = false; trace_await_return_path_close_on_source_close(); + + trace_migration_return_path_end_after(ms->rp_state.error); return ms->rp_state.error; } @@ -2301,66 +2307,107 @@ static int migration_maybe_pause(MigrationState *s, return s->state == new_state ? 0 : -EINVAL; } -/** - * migration_completion: Used by migration_thread when there's not much left. - * The caller 'breaks' the loop when this returns. - * - * @s: Current migration state - */ -static void migration_completion(MigrationState *s) +static int migration_completion_precopy(MigrationState *s, + int *current_active_state) { int ret; - int current_active_state = s->state; - if (s->state == MIGRATION_STATUS_ACTIVE) { - qemu_mutex_lock_iothread(); - s->downtime_start = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); - qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER, NULL); + qemu_mutex_lock_iothread(); + s->downtime_start = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); + qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER, NULL); - s->vm_old_state = runstate_get(); - global_state_store(); + s->vm_old_state = runstate_get(); + global_state_store(); - ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE); - trace_migration_completion_vm_stop(ret); - if (ret >= 0) { - ret = migration_maybe_pause(s, ¤t_active_state, - MIGRATION_STATUS_DEVICE); - } - if (ret >= 0) { - /* - * Inactivate disks except in COLO, and track that we - * have done so in order to remember to reactivate - * them if migration fails or is cancelled. - */ - s->block_inactive = !migrate_colo(); - migration_rate_set(RATE_LIMIT_DISABLED); - ret = qemu_savevm_state_complete_precopy(s->to_dst_file, false, - s->block_inactive); - } + ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE); + trace_migration_completion_vm_stop(ret); + if (ret < 0) { + goto out_unlock; + } - qemu_mutex_unlock_iothread(); + ret = migration_maybe_pause(s, current_active_state, + MIGRATION_STATUS_DEVICE); + if (ret < 0) { + goto out_unlock; + } - if (ret < 0) { - goto fail; - } - } else if (s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) { - trace_migration_completion_postcopy_end(); + /* + * Inactivate disks except in COLO, and track that we have done so in order + * to remember to reactivate them if migration fails or is cancelled. + */ + s->block_inactive = !migrate_colo(); + migration_rate_set(RATE_LIMIT_DISABLED); + ret = qemu_savevm_state_complete_precopy(s->to_dst_file, false, + s->block_inactive); +out_unlock: + qemu_mutex_unlock_iothread(); + return ret; +} - qemu_mutex_lock_iothread(); - qemu_savevm_state_complete_postcopy(s->to_dst_file); - qemu_mutex_unlock_iothread(); +static void migration_completion_postcopy(MigrationState *s) +{ + trace_migration_completion_postcopy_end(); + qemu_mutex_lock_iothread(); + qemu_savevm_state_complete_postcopy(s->to_dst_file); + qemu_mutex_unlock_iothread(); + + /* + * Shutdown the postcopy fast path thread. This is only needed when dest + * QEMU binary is old (7.1/7.2). QEMU 8.0+ doesn't need this. + */ + if (migrate_postcopy_preempt() && s->preempt_pre_7_2) { + postcopy_preempt_shutdown_file(s); + } + + trace_migration_completion_postcopy_end_after_complete(); +} + +static void migration_completion_failed(MigrationState *s, + int current_active_state) +{ + if (s->block_inactive && (s->state == MIGRATION_STATUS_ACTIVE || + s->state == MIGRATION_STATUS_DEVICE)) { /* - * Shutdown the postcopy fast path thread. This is only needed - * when dest QEMU binary is old (7.1/7.2). QEMU 8.0+ doesn't need - * this. + * If not doing postcopy, vm_start() will be called: let's + * regain control on images. */ - if (migrate_postcopy_preempt() && s->preempt_pre_7_2) { - postcopy_preempt_shutdown_file(s); + Error *local_err = NULL; + + qemu_mutex_lock_iothread(); + bdrv_activate_all(&local_err); + if (local_err) { + error_report_err(local_err); + } else { + s->block_inactive = false; } + qemu_mutex_unlock_iothread(); + } - trace_migration_completion_postcopy_end_after_complete(); + migrate_set_state(&s->state, current_active_state, + MIGRATION_STATUS_FAILED); +} + +/** + * migration_completion: Used by migration_thread when there's not much left. + * The caller 'breaks' the loop when this returns. + * + * @s: Current migration state + */ +static void migration_completion(MigrationState *s) +{ + int ret = 0; + int current_active_state = s->state; + + if (s->state == MIGRATION_STATUS_ACTIVE) { + ret = migration_completion_precopy(s, ¤t_active_state); + } else if (s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) { + migration_completion_postcopy(s); } else { + ret = -1; + } + + if (ret < 0) { goto fail; } @@ -2370,14 +2417,8 @@ static void migration_completion(MigrationState *s) * it will wait for the destination to send it's status in * a SHUT command). */ - if (s->rp_state.rp_thread_created) { - int rp_error; - trace_migration_return_path_end_before(); - rp_error = await_return_path_close_on_source(s); - trace_migration_return_path_end_after(rp_error); - if (rp_error) { - goto fail; - } + if (close_return_path_on_source(s) < 0) { + goto fail; } if (qemu_file_get_error(s->to_dst_file)) { @@ -2397,26 +2438,7 @@ static void migration_completion(MigrationState *s) return; fail: - if (s->block_inactive && (s->state == MIGRATION_STATUS_ACTIVE || - s->state == MIGRATION_STATUS_DEVICE)) { - /* - * If not doing postcopy, vm_start() will be called: let's - * regain control on images. - */ - Error *local_err = NULL; - - qemu_mutex_lock_iothread(); - bdrv_activate_all(&local_err); - if (local_err) { - error_report_err(local_err); - } else { - s->block_inactive = false; - } - qemu_mutex_unlock_iothread(); - } - - migrate_set_state(&s->state, current_active_state, - MIGRATION_STATUS_FAILED); + migration_completion_failed(s, current_active_state); } /**
Current migration_completion function is a bit long. Refactor the long implementation into different subfunctions: - migration_completion_precopy: completion code related to precopy - migration_completion_postcopy: completion code related to postcopy - close_return_path_on_source: rp thread related cleanup on migration completion. It is named to match with open_return_path_on_source. This improves readability and is easier for future updates (e.g. add new subfunctions when completion code related to new features are needed). No functional changes intended. Signed-off-by: Wei Wang <wei.w.wang@intel.com> --- Changelog: - Merge await_return_path_close_on_source into close_return_path_on_source as the later basically just calls the previous; - make migration_completion_postcopy "void" as it doesn't return a value. migration/migration.c | 174 ++++++++++++++++++++++++------------------ 1 file changed, 98 insertions(+), 76 deletions(-)