Function vdev_stat_update

freebsd/contrib/openzfs/module/zfs/vdev.c:4297–4507

}

void
vdev_stat_update(zio_t *zio, uint64_t psize)
{
	spa_t *spa = zio->io_spa;
	vdev_t *rvd = spa->spa_root_vdev;
	vdev_t *vd = zio->io_vd ? zio->io_vd : rvd;
	vdev_t *pvd;
	uint64_t txg = zio->io_txg;
	vdev_stat_t *vs = &vd->vdev_stat;
	vdev_stat_ex_t *vsx = &vd->vdev_stat_ex;
	zio_type_t type = zio->io_type;
	int flags = zio->io_flags;

	/*
	 * If this i/o is a gang leader, it didn't do any actual work.
	 */
	if (zio->io_gang_tree)
		return;

	if (zio->io_error == 0) {
		/*
		 * If this is a root i/o, don't count it -- we've already
		 * counted the top-level vdevs, and vdev_get_stats() will
		 * aggregate them when asked.  This reduces contention on
		 * the root vdev_stat_lock and implicitly handles blocks
		 * that compress away to holes, for which there is no i/o.
		 * (Holes never create vdev children, so all the counters
		 * remain zero, which is what we want.)
		 *
		 * Note: this only applies to successful i/o (io_error == 0)
		 * because unlike i/o counts, errors are not additive.
		 * When reading a ditto block, for example, failure of
		 * one top-level vdev does not imply a root-level error.
		 */
		if (vd == rvd)
			return;

		ASSERT(vd == zio->io_vd);

		if (flags & ZIO_FLAG_IO_BYPASS)
			return;

		mutex_enter(&vd->vdev_stat_lock);

		if (flags & ZIO_FLAG_IO_REPAIR) {
			/*
			 * Repair is the result of a resilver issued by the
			 * scan thread (spa_sync).
			 */
			if (flags & ZIO_FLAG_SCAN_THREAD) {
				dsl_scan_t *scn = spa->spa_dsl_pool->dp_scan;
				dsl_scan_phys_t *scn_phys = &scn->scn_phys;
				uint64_t *processed = &scn_phys->scn_processed;

				if (vd->vdev_ops->vdev_op_leaf)
					atomic_add_64(processed, psize);
				vs->vs_scan_processed += psize;
			}