On 5/6/21 8:54 AM, Philippe Mathieu-Daudé wrote:
static void notify_guest_bh(void *opaque) { VirtIOBlockDataPlane *s = opaque; - unsigned nvqs = s->conf->num_queues; - unsigned long bitmap[BITS_TO_LONGS(nvqs)]; - unsigned j;- memcpy(bitmap, s->batch_notify_vqs, sizeof(bitmap));- memset(s->batch_notify_vqs, 0, sizeof(bitmap)); - - for (j = 0; j < nvqs; j += BITS_PER_LONG) { - unsigned long bits = bitmap[j / BITS_PER_LONG]; - - while (bits != 0) { - unsigned i = j + ctzl(bits); + for (unsigned i = 0; i < s->conf->num_queues; i++) {
Is this bitmap dense enough that you want to iterate by index, or is it sparse enough to iterate via find_first_bit/find_next_bit?
In either case, leave the copy of s->conf->num_queues to a local variable. r~
