| Message ID | 20200217150246.29180-9-vsementsov@virtuozzo.com |
|---|---|
| State | New |
| Headers | show |
| Series | Fix error handling during bitmap postcopy | expand |
On 17/02/2020 18:02, Vladimir Sementsov-Ogievskiy wrote: > Keep bitmap state for disabled bitmaps too. Keep the state until the > end of the process. It's needed for the following commit to implement > bitmap postcopy canceling. > > To clean-up the new list the following logic is used: > We need two events to consider bitmap migration finished: > 1. chunk with DIRTY_BITMAP_MIG_FLAG_COMPLETE flag should be received > 2. dirty_bitmap_mig_before_vm_start should be called > These two events may come in any order, so we understand which one is > last, and on the last of them we remove bitmap migration state from the > list. > > Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> > --- > migration/block-dirty-bitmap.c | 64 +++++++++++++++++++++++----------- > 1 file changed, 43 insertions(+), 21 deletions(-) > > diff --git a/migration/block-dirty-bitmap.c b/migration/block-dirty-bitmap.c > index 9cc750d93b..1329db8d7d 100644 > --- a/migration/block-dirty-bitmap.c > +++ b/migration/block-dirty-bitmap.c > @@ -132,6 +132,7 @@ typedef struct LoadBitmapState { > BlockDriverState *bs; > BdrvDirtyBitmap *bitmap; > bool migrated; > + bool enabled; > } LoadBitmapState; > > /* State of the dirty bitmap migration (DBM) during load process */ > @@ -142,8 +143,10 @@ typedef struct DBMLoadState { > BlockDriverState *bs; > BdrvDirtyBitmap *bitmap; > > - GSList *enabled_bitmaps; > - QemuMutex lock; /* protect enabled_bitmaps */ > + bool before_vm_start_handled; /* set in dirty_bitmap_mig_before_vm_start */ > + > + GSList *bitmaps; > + QemuMutex lock; /* protect bitmaps */ > } DBMLoadState; > > typedef struct DBMState { > @@ -458,6 +461,7 @@ static int dirty_bitmap_load_start(QEMUFile *f, DBMLoadState *s) > Error *local_err = NULL; > uint32_t granularity = qemu_get_be32(f); > uint8_t flags = qemu_get_byte(f); > + LoadBitmapState *b; > > if (s->bitmap) { > error_report("Bitmap with the same name ('%s') already exists on " > @@ -484,45 +488,59 @@ static int dirty_bitmap_load_start(QEMUFile *f, DBMLoadState *s) > > bdrv_disable_dirty_bitmap(s->bitmap); > if (flags & DIRTY_BITMAP_MIG_START_FLAG_ENABLED) { > - LoadBitmapState *b; > - > bdrv_dirty_bitmap_create_successor(s->bitmap, &local_err); > if (local_err) { > error_report_err(local_err); > return -EINVAL; > } > - > - b = g_new(LoadBitmapState, 1); > - b->bs = s->bs; > - b->bitmap = s->bitmap; > - b->migrated = false; > - s->enabled_bitmaps = g_slist_prepend(s->enabled_bitmaps, b); > } > > + b = g_new(LoadBitmapState, 1); > + b->bs = s->bs; > + b->bitmap = s->bitmap; > + b->migrated = false; > + b->enabled = flags & DIRTY_BITMAP_MIG_START_FLAG_ENABLED, > + > + s->bitmaps = g_slist_prepend(s->bitmaps, b); > + > return 0; > } > > -void dirty_bitmap_mig_before_vm_start(void) > +/* > + * before_vm_start_handle_item > + * > + * g_slist_foreach helper > + * > + * item is LoadBitmapState* > + * opaque is DBMLoadState* > + */ > +static void before_vm_start_handle_item(void *item, void *opaque) > { > - DBMLoadState *s = &dbm_state.load; > - GSList *item; > - > - qemu_mutex_lock(&s->lock); > - > - for (item = s->enabled_bitmaps; item; item = g_slist_next(item)) { > - LoadBitmapState *b = item->data; > + DBMLoadState *s = opaque; > + LoadBitmapState *b = item; > > + if (b->enabled) { > if (b->migrated) { > bdrv_enable_dirty_bitmap(b->bitmap); > } else { > bdrv_dirty_bitmap_enable_successor(b->bitmap); > } > + } > > + if (b->migrated) { > + s->bitmaps = g_slist_remove(s->bitmaps, b); > g_free(b); > } > +} > > - g_slist_free(s->enabled_bitmaps); > - s->enabled_bitmaps = NULL; > +void dirty_bitmap_mig_before_vm_start(void) > +{ > + DBMLoadState *s = &dbm_state.load; > + qemu_mutex_lock(&s->lock); > + > + assert(!s->before_vm_start_handled); > + g_slist_foreach(s->bitmaps, before_vm_start_handle_item, s); > + s->before_vm_start_handled = true; > > qemu_mutex_unlock(&s->lock); > } > @@ -539,11 +557,15 @@ static void dirty_bitmap_load_complete(QEMUFile *f, DBMLoadState *s) > bdrv_reclaim_dirty_bitmap(s->bitmap, &error_abort); > } > > - for (item = s->enabled_bitmaps; item; item = g_slist_next(item)) { > + for (item = s->bitmaps; item; item = g_slist_next(item)) { > LoadBitmapState *b = item->data; > > if (b->bitmap == s->bitmap) { > b->migrated = true; > + if (s->before_vm_start_handled) { > + s->bitmaps = g_slist_remove(s->bitmaps, b); > + g_free(b); > + } > break; > } > } > Reviewed-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
On 2/17/20 9:02 AM, Vladimir Sementsov-Ogievskiy wrote: > Keep bitmap state for disabled bitmaps too. Keep the state until the > end of the process. It's needed for the following commit to implement > bitmap postcopy canceling. > > To clean-up the new list the following logic is used: > We need two events to consider bitmap migration finished: > 1. chunk with DIRTY_BITMAP_MIG_FLAG_COMPLETE flag should be received > 2. dirty_bitmap_mig_before_vm_start should be called > These two events may come in any order, so we understand which one is > last, and on the last of them we remove bitmap migration state from the > list. > > Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> > --- > migration/block-dirty-bitmap.c | 64 +++++++++++++++++++++++----------- > 1 file changed, 43 insertions(+), 21 deletions(-) > @@ -484,45 +488,59 @@ static int dirty_bitmap_load_start(QEMUFile *f, DBMLoadState *s) > > bdrv_disable_dirty_bitmap(s->bitmap); > if (flags & DIRTY_BITMAP_MIG_START_FLAG_ENABLED) { > - LoadBitmapState *b; > - > bdrv_dirty_bitmap_create_successor(s->bitmap, &local_err); > if (local_err) { > error_report_err(local_err); > return -EINVAL; > } > - > - b = g_new(LoadBitmapState, 1); > - b->bs = s->bs; > - b->bitmap = s->bitmap; > - b->migrated = false; > - s->enabled_bitmaps = g_slist_prepend(s->enabled_bitmaps, b); > } > > + b = g_new(LoadBitmapState, 1); > + b->bs = s->bs; > + b->bitmap = s->bitmap; > + b->migrated = false; > + b->enabled = flags & DIRTY_BITMAP_MIG_START_FLAG_ENABLED, > + > + s->bitmaps = g_slist_prepend(s->bitmaps, b); Did you really mean to use a comma operator there, or should that be ';'?
24.07.2020 00:30, Eric Blake wrote: > On 2/17/20 9:02 AM, Vladimir Sementsov-Ogievskiy wrote: >> Keep bitmap state for disabled bitmaps too. Keep the state until the >> end of the process. It's needed for the following commit to implement >> bitmap postcopy canceling. >> >> To clean-up the new list the following logic is used: >> We need two events to consider bitmap migration finished: >> 1. chunk with DIRTY_BITMAP_MIG_FLAG_COMPLETE flag should be received >> 2. dirty_bitmap_mig_before_vm_start should be called >> These two events may come in any order, so we understand which one is >> last, and on the last of them we remove bitmap migration state from the >> list. >> >> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> >> --- >> migration/block-dirty-bitmap.c | 64 +++++++++++++++++++++++----------- >> 1 file changed, 43 insertions(+), 21 deletions(-) > >> @@ -484,45 +488,59 @@ static int dirty_bitmap_load_start(QEMUFile *f, DBMLoadState *s) >> bdrv_disable_dirty_bitmap(s->bitmap); >> if (flags & DIRTY_BITMAP_MIG_START_FLAG_ENABLED) { >> - LoadBitmapState *b; >> - >> bdrv_dirty_bitmap_create_successor(s->bitmap, &local_err); >> if (local_err) { >> error_report_err(local_err); >> return -EINVAL; >> } >> - >> - b = g_new(LoadBitmapState, 1); >> - b->bs = s->bs; >> - b->bitmap = s->bitmap; >> - b->migrated = false; >> - s->enabled_bitmaps = g_slist_prepend(s->enabled_bitmaps, b); >> } >> + b = g_new(LoadBitmapState, 1); >> + b->bs = s->bs; >> + b->bitmap = s->bitmap; >> + b->migrated = false; >> + b->enabled = flags & DIRTY_BITMAP_MIG_START_FLAG_ENABLED, >> + >> + s->bitmaps = g_slist_prepend(s->bitmaps, b); > > Did you really mean to use a comma operator there, or should that be ';'? > Of course, it should be ';':)
diff --git a/migration/block-dirty-bitmap.c b/migration/block-dirty-bitmap.c index 9cc750d93b..1329db8d7d 100644 --- a/migration/block-dirty-bitmap.c +++ b/migration/block-dirty-bitmap.c @@ -132,6 +132,7 @@ typedef struct LoadBitmapState { BlockDriverState *bs; BdrvDirtyBitmap *bitmap; bool migrated; + bool enabled; } LoadBitmapState; /* State of the dirty bitmap migration (DBM) during load process */ @@ -142,8 +143,10 @@ typedef struct DBMLoadState { BlockDriverState *bs; BdrvDirtyBitmap *bitmap; - GSList *enabled_bitmaps; - QemuMutex lock; /* protect enabled_bitmaps */ + bool before_vm_start_handled; /* set in dirty_bitmap_mig_before_vm_start */ + + GSList *bitmaps; + QemuMutex lock; /* protect bitmaps */ } DBMLoadState; typedef struct DBMState { @@ -458,6 +461,7 @@ static int dirty_bitmap_load_start(QEMUFile *f, DBMLoadState *s) Error *local_err = NULL; uint32_t granularity = qemu_get_be32(f); uint8_t flags = qemu_get_byte(f); + LoadBitmapState *b; if (s->bitmap) { error_report("Bitmap with the same name ('%s') already exists on " @@ -484,45 +488,59 @@ static int dirty_bitmap_load_start(QEMUFile *f, DBMLoadState *s) bdrv_disable_dirty_bitmap(s->bitmap); if (flags & DIRTY_BITMAP_MIG_START_FLAG_ENABLED) { - LoadBitmapState *b; - bdrv_dirty_bitmap_create_successor(s->bitmap, &local_err); if (local_err) { error_report_err(local_err); return -EINVAL; } - - b = g_new(LoadBitmapState, 1); - b->bs = s->bs; - b->bitmap = s->bitmap; - b->migrated = false; - s->enabled_bitmaps = g_slist_prepend(s->enabled_bitmaps, b); } + b = g_new(LoadBitmapState, 1); + b->bs = s->bs; + b->bitmap = s->bitmap; + b->migrated = false; + b->enabled = flags & DIRTY_BITMAP_MIG_START_FLAG_ENABLED, + + s->bitmaps = g_slist_prepend(s->bitmaps, b); + return 0; } -void dirty_bitmap_mig_before_vm_start(void) +/* + * before_vm_start_handle_item + * + * g_slist_foreach helper + * + * item is LoadBitmapState* + * opaque is DBMLoadState* + */ +static void before_vm_start_handle_item(void *item, void *opaque) { - DBMLoadState *s = &dbm_state.load; - GSList *item; - - qemu_mutex_lock(&s->lock); - - for (item = s->enabled_bitmaps; item; item = g_slist_next(item)) { - LoadBitmapState *b = item->data; + DBMLoadState *s = opaque; + LoadBitmapState *b = item; + if (b->enabled) { if (b->migrated) { bdrv_enable_dirty_bitmap(b->bitmap); } else { bdrv_dirty_bitmap_enable_successor(b->bitmap); } + } + if (b->migrated) { + s->bitmaps = g_slist_remove(s->bitmaps, b); g_free(b); } +} - g_slist_free(s->enabled_bitmaps); - s->enabled_bitmaps = NULL; +void dirty_bitmap_mig_before_vm_start(void) +{ + DBMLoadState *s = &dbm_state.load; + qemu_mutex_lock(&s->lock); + + assert(!s->before_vm_start_handled); + g_slist_foreach(s->bitmaps, before_vm_start_handle_item, s); + s->before_vm_start_handled = true; qemu_mutex_unlock(&s->lock); } @@ -539,11 +557,15 @@ static void dirty_bitmap_load_complete(QEMUFile *f, DBMLoadState *s) bdrv_reclaim_dirty_bitmap(s->bitmap, &error_abort); } - for (item = s->enabled_bitmaps; item; item = g_slist_next(item)) { + for (item = s->bitmaps; item; item = g_slist_next(item)) { LoadBitmapState *b = item->data; if (b->bitmap == s->bitmap) { b->migrated = true; + if (s->before_vm_start_handled) { + s->bitmaps = g_slist_remove(s->bitmaps, b); + g_free(b); + } break; } }
Keep bitmap state for disabled bitmaps too. Keep the state until the end of the process. It's needed for the following commit to implement bitmap postcopy canceling. To clean-up the new list the following logic is used: We need two events to consider bitmap migration finished: 1. chunk with DIRTY_BITMAP_MIG_FLAG_COMPLETE flag should be received 2. dirty_bitmap_mig_before_vm_start should be called These two events may come in any order, so we understand which one is last, and on the last of them we remove bitmap migration state from the list. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> --- migration/block-dirty-bitmap.c | 64 +++++++++++++++++++++++----------- 1 file changed, 43 insertions(+), 21 deletions(-)