search for: balloon_free_pages_support

...= find_next_bit(bitmap, size, nr); *ram_addr_abs = next << TARGET_PAGE_BITS; return (next - base) << TARGET_PAGE_BITS; } @@ -1415,6 +1412,9 @@ void free_xbzrle_decoded_buf(void) static void migration_bitmap_free(struct BitmapRcu *bmap) { g_free(bmap->bmap); + if (balloon_free_pages_support()) { + g_free(bmap->free_pages_bmap); + } g_free(bmap->unsentmap); g_free(bmap); } @@ -1873,6 +1873,28 @@ err: return ret; } +static void filter_out_guest_free_pages(unsigned long *free_pages_bmap) +{ + RAMBlock *block; + DirtyMemoryBlocks *blocks; + unsi...

...balloon_event_fn = NULL; balloon_stat_fn = NULL; + balloon_free_pages_fn = NULL; balloon_opaque = NULL; } @@ -116,3 +122,23 @@ void qmp_balloon(int64_t target, Error **errp) trace_balloon_event(balloon_opaque, target); balloon_event_fn(balloon_opaque, target); } + +bool balloon_free_pages_support(void) +{ + return balloon_free_pages_fn ? true : false; +} + +int balloon_get_free_pages(unsigned long *free_pages_bitmap, + unsigned long *free_pages_count) +{ + if (!balloon_free_pages_fn) { + return -1; + } + + if (!free_pages_bitmap || !free_pages_co...

...NULL; > + balloon_free_pages_fn = NULL; > balloon_opaque = NULL; > } > > @@ -116,3 +122,23 @@ void qmp_balloon(int64_t target, Error **errp) > trace_balloon_event(balloon_opaque, target); > balloon_event_fn(balloon_opaque, target); > } > + > +bool balloon_free_pages_support(void) > +{ > + return balloon_free_pages_fn ? true : false; > +} > + > +int balloon_get_free_pages(unsigned long *free_pages_bitmap, > + unsigned long *free_pages_count) > +{ > + if (!balloon_free_pages_fn) { > + return -1; > +...

The current QEMU live migration implementation mark the all the guest's RAM pages as dirtied in the ram bulk stage, all these pages will be processed and that takes quit a lot of CPU cycles. >From guest's point of view, it doesn't care about the content in free pages. We can make use of this fact and skip processing the free pages in the ram bulk stage, it can save a lot CPU cycles

The current QEMU live migration implementation mark the all the guest's RAM pages as dirtied in the ram bulk stage, all these pages will be processed and that takes quit a lot of CPU cycles. >From guest's point of view, it doesn't care about the content in free pages. We can make use of this fact and skip processing the free pages in the ram bulk stage, it can save a lot CPU cycles

...----- > 1 file changed, 46 insertions(+), 6 deletions(-) > > @@ -1945,6 +1971,20 @@ static int ram_save_setup(QEMUFile *f, void *opaque) > DIRTY_MEMORY_MIGRATION); > } > memory_global_dirty_log_start(); > + > + if (balloon_free_pages_support() && > + balloon_get_free_pages(migration_bitmap_rcu->free_pages_bmap, > + &free_pages_count) == 0) { > + qemu_mutex_unlock_iothread(); > + while (balloon_get_free_pages(migration_bitmap_rcu->free_pages_bmap, > +...

...ed long *free_pages_bitmap, > + unsigned long *free_pages_count) > +{ > + VirtIOBalloon *s = opaque; > + VirtIODevice *vdev = VIRTIO_DEVICE(s); > + VirtQueueElement *elem = s->free_pages_vq_elem; > + int len; > + > + if (!balloon_free_pages_supported(s)) { > + return -1; > + } > + > + if (s->req_status == NOT_STARTED) { > + s->free_pages_bitmap = free_pages_bitmap; > + s->req_status = STARTED; > + s->mem_layout.low_mem = pc_get_lowmem(PC_MACHINE(current_machine)); Please don&...

...+++++------ > 1 file changed, 46 insertions(+), 6 deletions(-) > @@ -1945,6 +1971,20 @@ static int ram_save_setup(QEMUFile *f, void *opaque) > DIRTY_MEMORY_MIGRATION); > } > memory_global_dirty_log_start(); > + > + if (balloon_free_pages_support() && > + balloon_get_free_pages(migration_bitmap_rcu->free_pages_bmap, > + &free_pages_count) == 0) { > + qemu_mutex_unlock_iothread(); > + while (balloon_get_free_pages(migration_bitmap_rcu->free_pages_bmap, > +...