* Alexey Perevalov (a.pereva...@samsung.com) wrote: > This patch adds ability to track down already received > pages, it's necessary for calculation vCPU block time in > postcopy migration feature, maybe for restore after > postcopy migration failure. > Also it's necessary to solve shared memory issue in > postcopy livemigration. Information about received pages > will be transferred to the software virtual bridge > (e.g. OVS-VSWITCHD), to avoid fallocate (unmap) for > already received pages. fallocate syscall is required for > remmaped shared memory, due to remmaping itself blocks > ioctl(UFFDIO_COPY, ioctl in this case will end with EEXIT > error (struct page is exists after remmap). > > Bitmap is placed into RAMBlock as another postcopy/precopy > related bitmaps. > > Signed-off-by: Alexey Perevalov <a.pereva...@samsung.com> > --- > include/exec/ram_addr.h | 2 ++ > migration/postcopy-ram.c | 11 ++++++++--- > migration/ram.c | 33 +++++++++++++++++++++++++++++++++ > migration/ram.h | 5 +++++ > migration/savevm.c | 1 + > 5 files changed, 49 insertions(+), 3 deletions(-) > > diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h > index 140efa8..c2c1dfe 100644 > --- a/include/exec/ram_addr.h > +++ b/include/exec/ram_addr.h > @@ -47,6 +47,8 @@ struct RAMBlock { > * of the postcopy phase > */ > unsigned long *unsentmap; > + /* bitmap of already received pages in postcopy */ > + unsigned long *receivedmap; > }; > > static inline bool offset_in_ramblock(RAMBlock *b, ram_addr_t offset) > diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c > index 38a429a..5ac3ed2 100644 > --- a/migration/postcopy-ram.c > +++ b/migration/postcopy-ram.c > @@ -562,8 +562,13 @@ int postcopy_ram_enable_notify(MigrationIncomingState > *mis) > } > > static int qemu_ufd_copy_ioctl(int userfault_fd, void *host_addr, > - void *from_addr, uint64_t pagesize) > + void *from_addr, uint64_t pagesize, RAMBlock *rb) > { > + /* received page isn't feature of blocktime calculation, > + * it's more general entity, so keep it here, > + * but gup betwean two following operation could be high, > + * and in this case blocktime for such small interval will be lost */ > + set_receivedmap_by_addr(host_addr, rb); > if (from_addr) { > struct uffdio_copy copy_struct; > copy_struct.dst = (uint64_t)(uintptr_t)host_addr; > @@ -595,7 +600,7 @@ int postcopy_place_page(MigrationIncomingState *mis, void > *host, void *from, > * which would be slightly cheaper, but we'd have to be careful > * of the order of updating our page state. > */ > - if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, from, pagesize)) { > + if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, from, pagesize, rb)) {
In your first patch of the series you changed postcopy_place_page to take a RAMBlock* *rather* than a pagesize; perhaps it would be better to do the same here? Other than that looks pretty good. Dave > int e = errno; > error_report("%s: %s copy host: %p from: %p (size: %zd)", > __func__, strerror(e), host, from, pagesize); > @@ -619,7 +624,7 @@ int postcopy_place_page_zero(MigrationIncomingState *mis, > void *host, > > pagesize = qemu_ram_pagesize(rb); > if (pagesize == getpagesize()) { > - if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, 0, getpagesize())) { > + if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, 0, getpagesize(), > rb)) { > int e = errno; > error_report("%s: %s zero host: %p", > __func__, strerror(e), host); > diff --git a/migration/ram.c b/migration/ram.c > index f50479d..f5ea3c2 100644 > --- a/migration/ram.c > +++ b/migration/ram.c > @@ -151,6 +151,34 @@ out: > return ret; > } > > +void init_receivedmap(void) > +{ > + RAMBlock *rb; > + > + RAMBLOCK_FOREACH(rb) { > + unsigned long pages; > + pages = rb->max_length >> TARGET_PAGE_BITS; > + rb->receivedmap = bitmap_new(pages); > + } > +} > + > +static unsigned long int get_received_bit_offset(void *host_addr, RAMBlock > *rb) > +{ > + uint64_t host_addr_offset = (uint64_t)(uintptr_t)(host_addr > + - (void *)rb->host); > + return host_addr_offset >> TARGET_PAGE_BITS; > +} > + > +int test_receivedmap_by_addr(void *host_addr, RAMBlock *rb) > +{ > + return test_bit(get_received_bit_offset(host_addr, rb), rb->receivedmap); > +} > + > +void set_receivedmap_by_addr(void *host_addr, RAMBlock *rb) > +{ > + set_bit_atomic(get_received_bit_offset(host_addr, rb), rb->receivedmap); > +} > + > /* > * An outstanding page request, on the source, having been received > * and queued > @@ -2324,8 +2352,13 @@ static int ram_load_setup(QEMUFile *f, void *opaque) > > static int ram_load_cleanup(void *opaque) > { > + RAMBlock *rb; > xbzrle_load_cleanup(); > compress_threads_load_cleanup(); > + > + RAMBLOCK_FOREACH(rb) { > + g_free(rb->receivedmap); > + } > return 0; > } > > diff --git a/migration/ram.h b/migration/ram.h > index c081fde..7048ff9 100644 > --- a/migration/ram.h > +++ b/migration/ram.h > @@ -52,4 +52,9 @@ int ram_discard_range(const char *block_name, uint64_t > start, size_t length); > int ram_postcopy_incoming_init(MigrationIncomingState *mis); > > void ram_handle_compressed(void *host, uint8_t ch, uint64_t size); > + > +void init_receivedmap(void); > +int test_receivedmap_by_addr(void *host_addr, RAMBlock *rb); > +void set_receivedmap_by_addr(void *host_addr, RAMBlock *rb); > + > #endif > diff --git a/migration/savevm.c b/migration/savevm.c > index 31158da..668d3bb 100644 > --- a/migration/savevm.c > +++ b/migration/savevm.c > @@ -1372,6 +1372,7 @@ static int > loadvm_postcopy_handle_advise(MigrationIncomingState *mis) > return -1; > } > > + init_receivedmap(); > remote_pagesize_summary = qemu_get_be64(mis->from_src_file); > local_pagesize_summary = ram_pagesize_summary(); > > -- > 1.9.1 > -- Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK