| Message ID | 20170724150413.19357-1-dgilbert@redhat.com |
|---|---|
| State | New |
| Headers | show |
On 24/07/2017 17:04, Dr. David Alan Gilbert (git) wrote: > From: Dr. David Alan Gilbert <dgilbert@redhat.com> > > This code has an optimised, word aligned version, and a boring > unaligned version. Recently 084140bd498909 fixed a missing offset > addition from the core of both versions. However, the offset isn't > necessarily aligned and thus the choice between the two versions > needs fixing up to also include the offset. > > Symptom: > A few stuck unsent pages during migration; not normally noticed > unless under very low bandwidth in which case the migration may get > stuck never ending and never performing a 2nd sync; noticed by > a hanging postcopy-test on a very heavily loaded system. > > Fixes: 084140bd498909 > > Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> > Reported-by: Alex Benneé <alex.benee@linaro.org> > Tested-by: Alex Bennée <alex.bennee@linaro.org> > --- > include/exec/ram_addr.h | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h > index c04f4f67f6..c802f7f364 100644 > --- a/include/exec/ram_addr.h > +++ b/include/exec/ram_addr.h > @@ -378,15 +378,16 @@ uint64_t cpu_physical_memory_sync_dirty_bitmap(RAMBlock *rb, > { > ram_addr_t addr; > unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS); Nice catch! "page" can now be moved to the "if", exactly where you've removed the declaration of "word". Paolo > + unsigned long word = BIT_WORD((start + rb->offset) >> TARGET_PAGE_BITS); > uint64_t num_dirty = 0; > unsigned long *dest = rb->bmap; > > /* start address is aligned at the start of a word? */ > - if (((page * BITS_PER_LONG) << TARGET_PAGE_BITS) == start) { > + if (((word * BITS_PER_LONG) << TARGET_PAGE_BITS) == > + (start + rb->offset)) { > int k; > int nr = BITS_TO_LONGS(length >> TARGET_PAGE_BITS); > unsigned long * const *src; > - unsigned long word = BIT_WORD((start + rb->offset) >> TARGET_PAGE_BITS); > unsigned long idx = (word * BITS_PER_LONG) / DIRTY_MEMORY_BLOCK_SIZE; > unsigned long offset = BIT_WORD((word * BITS_PER_LONG) % > DIRTY_MEMORY_BLOCK_SIZE); >
diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h index c04f4f67f6..c802f7f364 100644 --- a/include/exec/ram_addr.h +++ b/include/exec/ram_addr.h @@ -378,15 +378,16 @@ uint64_t cpu_physical_memory_sync_dirty_bitmap(RAMBlock *rb, { ram_addr_t addr; unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS); + unsigned long word = BIT_WORD((start + rb->offset) >> TARGET_PAGE_BITS); uint64_t num_dirty = 0; unsigned long *dest = rb->bmap; /* start address is aligned at the start of a word? */ - if (((page * BITS_PER_LONG) << TARGET_PAGE_BITS) == start) { + if (((word * BITS_PER_LONG) << TARGET_PAGE_BITS) == + (start + rb->offset)) { int k; int nr = BITS_TO_LONGS(length >> TARGET_PAGE_BITS); unsigned long * const *src; - unsigned long word = BIT_WORD((start + rb->offset) >> TARGET_PAGE_BITS); unsigned long idx = (word * BITS_PER_LONG) / DIRTY_MEMORY_BLOCK_SIZE; unsigned long offset = BIT_WORD((word * BITS_PER_LONG) % DIRTY_MEMORY_BLOCK_SIZE);