| Message ID | 20180502104740.12123-18-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 | 45 ++++++++++++++++++++++++++++++++++++++++++++- > migration/trace-events | 1 + > 2 files changed, 45 insertions(+), 1 deletion(-) > > diff --git a/migration/ram.c b/migration/ram.c > index 118460109b..2821e15cc2 100644 > --- a/migration/ram.c > +++ b/migration/ram.c > @@ -2291,6 +2291,41 @@ static int ram_init_all(RAMState **rsp) > return 0; > } > > +static void ram_state_resume_prepare(RAMState *rs, QEMUFile *out) > +{ > + RAMBlock *block; > + uint64_t 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; > + /* > + * Disable the bulk stage, otherwise we'll resend the whole RAM no > + * matter what we have sent. > + */ > + rs->ram_bulk_stage = false; > + > + /* Update RAMState cache of output QEMUFile */ > + rs->f = out; > + > + 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 > @@ -3286,8 +3321,16 @@ 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, s->to_dst_file); > + > + return 0; > } > > static SaveVMHandlers savevm_ram_handlers = { > diff --git a/migration/trace-events b/migration/trace-events > index 53243e17ec..46c5ca1dba 100644 > --- a/migration/trace-events > +++ b/migration/trace-events > @@ -88,6 +88,7 @@ ram_dirty_bitmap_reload_complete(char *str) "%s" > ram_dirty_bitmap_sync_start(void) "" > ram_dirty_bitmap_sync_wait(void) "" > ram_dirty_bitmap_sync_complete(void) "" > +ram_state_resume_prepare(uint64_t v) "%ld" That should be "%" PRId64 But otherwise looks OK, so with that change: Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> > # migration/migration.c > await_return_path_close_on_source_close(void) "" > -- > 2.14.3 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
diff --git a/migration/ram.c b/migration/ram.c index 118460109b..2821e15cc2 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -2291,6 +2291,41 @@ static int ram_init_all(RAMState **rsp) return 0; } +static void ram_state_resume_prepare(RAMState *rs, QEMUFile *out) +{ + RAMBlock *block; + uint64_t 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; + /* + * Disable the bulk stage, otherwise we'll resend the whole RAM no + * matter what we have sent. + */ + rs->ram_bulk_stage = false; + + /* Update RAMState cache of output QEMUFile */ + rs->f = out; + + 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 @@ -3286,8 +3321,16 @@ 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, s->to_dst_file); + + return 0; } static SaveVMHandlers savevm_ram_handlers = { diff --git a/migration/trace-events b/migration/trace-events index 53243e17ec..46c5ca1dba 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -88,6 +88,7 @@ ram_dirty_bitmap_reload_complete(char *str) "%s" ram_dirty_bitmap_sync_start(void) "" ram_dirty_bitmap_sync_wait(void) "" ram_dirty_bitmap_sync_complete(void) "" +ram_state_resume_prepare(uint64_t 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 | 45 ++++++++++++++++++++++++++++++++++++++++++++- migration/trace-events | 1 + 2 files changed, 45 insertions(+), 1 deletion(-)