| Message ID | 1504081950-2528-26-git-send-email-peterx@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | Migration: postcopy failure recovery | expand |
* Peter Xu (peterx@redhat.com) wrote: > After we updated the dirty bitmaps of ramblocks, we also need to update > the critical fields in RAMState to make sure it is ready for a resume. > > Signed-off-by: Peter Xu <peterx@redhat.com> > --- > migration/ram.c | 37 ++++++++++++++++++++++++++++++++++++- > migration/trace-events | 1 + > 2 files changed, 37 insertions(+), 1 deletion(-) > > diff --git a/migration/ram.c b/migration/ram.c > index afabcf5..c5d9028 100644 > --- a/migration/ram.c > +++ b/migration/ram.c > @@ -1986,6 +1986,33 @@ static int ram_state_init(RAMState **rsp) > return 0; > } > > +static void ram_state_resume_prepare(RAMState *rs) > +{ > + RAMBlock *block; > + long pages = 0; > + > + /* > + * Postcopy is not using xbzrle/compression, so no need for that. > + * Also, since source are already halted, we don't need to care > + * about dirty page logging as well. > + */ > + > + RAMBLOCK_FOREACH(block) { > + pages += bitmap_count_one(block->bmap, > + block->used_length >> TARGET_PAGE_BITS); > + } > + > + /* This may not be aligned with current bitmaps. Recalculate. */ > + rs->migration_dirty_pages = pages; > + > + rs->last_seen_block = NULL; > + rs->last_sent_block = NULL; > + rs->last_page = 0; > + rs->last_version = ram_list.version; > + > + trace_ram_state_resume_prepare(pages); Yes, I think this is fine; I wonder what happens if pages is 0? However, Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> > +} > + > /* > * Each of ram_save_setup, ram_save_iterate and ram_save_complete has > * long-running RCU critical section. When rcu-reclaims in the code > @@ -2909,8 +2936,16 @@ out: > static int ram_resume_prepare(MigrationState *s, void *opaque) > { > RAMState *rs = *(RAMState **)opaque; > + int ret; > > - return ram_dirty_bitmap_sync_all(s, rs); > + ret = ram_dirty_bitmap_sync_all(s, rs); > + if (ret) { > + return ret; > + } > + > + ram_state_resume_prepare(rs); > + > + return 0; > } > > static SaveVMHandlers savevm_ram_handlers = { > diff --git a/migration/trace-events b/migration/trace-events > index 8962916..6e06283 100644 > --- a/migration/trace-events > +++ b/migration/trace-events > @@ -85,6 +85,7 @@ ram_dirty_bitmap_sync_start(void) "" > ram_dirty_bitmap_sync_wait(void) "" > ram_dirty_bitmap_sync_notify(void) "" > ram_dirty_bitmap_sync_complete(void) "" > +ram_state_resume_prepare(long v) "%ld" > > # migration/migration.c > await_return_path_close_on_source_close(void) "" > -- > 2.7.4 > > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
diff --git a/migration/ram.c b/migration/ram.c index afabcf5..c5d9028 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1986,6 +1986,33 @@ static int ram_state_init(RAMState **rsp) return 0; } +static void ram_state_resume_prepare(RAMState *rs) +{ + RAMBlock *block; + long pages = 0; + + /* + * Postcopy is not using xbzrle/compression, so no need for that. + * Also, since source are already halted, we don't need to care + * about dirty page logging as well. + */ + + RAMBLOCK_FOREACH(block) { + pages += bitmap_count_one(block->bmap, + block->used_length >> TARGET_PAGE_BITS); + } + + /* This may not be aligned with current bitmaps. Recalculate. */ + rs->migration_dirty_pages = pages; + + rs->last_seen_block = NULL; + rs->last_sent_block = NULL; + rs->last_page = 0; + rs->last_version = ram_list.version; + + trace_ram_state_resume_prepare(pages); +} + /* * Each of ram_save_setup, ram_save_iterate and ram_save_complete has * long-running RCU critical section. When rcu-reclaims in the code @@ -2909,8 +2936,16 @@ out: static int ram_resume_prepare(MigrationState *s, void *opaque) { RAMState *rs = *(RAMState **)opaque; + int ret; - return ram_dirty_bitmap_sync_all(s, rs); + ret = ram_dirty_bitmap_sync_all(s, rs); + if (ret) { + return ret; + } + + ram_state_resume_prepare(rs); + + return 0; } static SaveVMHandlers savevm_ram_handlers = { diff --git a/migration/trace-events b/migration/trace-events index 8962916..6e06283 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -85,6 +85,7 @@ ram_dirty_bitmap_sync_start(void) "" ram_dirty_bitmap_sync_wait(void) "" ram_dirty_bitmap_sync_notify(void) "" ram_dirty_bitmap_sync_complete(void) "" +ram_state_resume_prepare(long v) "%ld" # migration/migration.c await_return_path_close_on_source_close(void) ""
After we updated the dirty bitmaps of ramblocks, we also need to update the critical fields in RAMState to make sure it is ready for a resume. Signed-off-by: Peter Xu <peterx@redhat.com> --- migration/ram.c | 37 ++++++++++++++++++++++++++++++++++++- migration/trace-events | 1 + 2 files changed, 37 insertions(+), 1 deletion(-)