| Message ID | 1501604245-33460-3-git-send-email-pbonzini@redhat.com |
|---|---|
| State | New |
| Headers | show |
On 1 August 2017 at 17:17, Paolo Bonzini <pbonzini@redhat.com> 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 Benneé <alex.benee@linaro.org> > > -- > v2 > Move 'page' inside the if (Comment from Paolo) > Message-Id: <20170724165125.29887-1-dgilbert@redhat.com> > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Something somewhere along the line seems to have mangled the unicode characters in Alex's name :-( Also, Alex's email address is typoed, and what should be the '---' marker has been written as '--' so the below-the-fold waffle is still hanging around in the commit. This doesn't seem worth rejecting the pull request on the eve of rc1 for, but it's still a bit sad :-( thanks -- PMM
* Peter Maydell (peter.maydell@linaro.org) wrote: > On 1 August 2017 at 17:17, Paolo Bonzini <pbonzini@redhat.com> 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 Benneé <alex.benee@linaro.org> > > > > -- > > v2 > > Move 'page' inside the if (Comment from Paolo) > > Message-Id: <20170724165125.29887-1-dgilbert@redhat.com> > > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> > > Something somewhere along the line seems to have mangled the > unicode characters in Alex's name :-( > Also, Alex's email address is typoed, and what should be the > '---' marker has been written as '--' so the below-the-fold waffle > is still hanging around in the commit. > > This doesn't seem worth rejecting the pull request on the > eve of rc1 for, but it's still a bit sad :-( Hmm yes, I think some of that's mine - the missing 'n' is certainly my fault; and I may have got his two 'e's in the wrong order, but I don't know what changed the encoding, that seems right on: https://lists.nongnu.org/archive/html/qemu-devel/2017-07/msg07417.html Dave > thanks > -- PMM -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
On 01/08/2017 20:04, Dr. David Alan Gilbert wrote: > * Peter Maydell (peter.maydell@linaro.org) wrote: >> On 1 August 2017 at 17:17, Paolo Bonzini <pbonzini@redhat.com> 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 Benneé <alex.benee@linaro.org> >>> >>> -- >>> v2 >>> Move 'page' inside the if (Comment from Paolo) >>> Message-Id: <20170724165125.29887-1-dgilbert@redhat.com> >>> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> >> >> Something somewhere along the line seems to have mangled the >> unicode characters in Alex's name :-( >> Also, Alex's email address is typoed, and what should be the >> '---' marker has been written as '--' so the below-the-fold waffle >> is still hanging around in the commit. >> >> This doesn't seem worth rejecting the pull request on the >> eve of rc1 for, but it's still a bit sad :-( > > Hmm yes, I think some of that's mine - the missing 'n' is certainly > my fault; and I may have got his two 'e's in the wrong order, > but I don't know what changed the encoding, that seems right on: > https://lists.nongnu.org/archive/html/qemu-devel/2017-07/msg07417.html The encoding is me. Paolo
Dr. David Alan Gilbert <dgilbert@redhat.com> writes: > * Peter Maydell (peter.maydell@linaro.org) wrote: >> On 1 August 2017 at 17:17, Paolo Bonzini <pbonzini@redhat.com> 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 Benneé <alex.benee@linaro.org> >> > >> > -- >> > v2 >> > Move 'page' inside the if (Comment from Paolo) >> > Message-Id: <20170724165125.29887-1-dgilbert@redhat.com> >> > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> >> >> Something somewhere along the line seems to have mangled the >> unicode characters in Alex's name :-( >> Also, Alex's email address is typoed, and what should be the >> '---' marker has been written as '--' so the below-the-fold waffle >> is still hanging around in the commit. >> >> This doesn't seem worth rejecting the pull request on the >> eve of rc1 for, but it's still a bit sad :-( > > Hmm yes, I think some of that's mine - the missing 'n' is certainly > my fault; and I may have got his two 'e's in the wrong order, > but I don't know what changed the encoding, that seems right on: > https://lists.nongnu.org/archive/html/qemu-devel/2017-07/msg07417.html Hmm also the acute accent should be on the second (not third) e ;-) -- Alex Bennée (breaking UTF-8 workflow since before it was cool)
diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h index c04f4f6..d017639 100644 --- a/include/exec/ram_addr.h +++ b/include/exec/ram_addr.h @@ -377,19 +377,20 @@ uint64_t cpu_physical_memory_sync_dirty_bitmap(RAMBlock *rb, uint64_t *real_dirty_pages) { 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); + unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS); rcu_read_lock();