void *td_arg;
} traverse_data_t;
+typedef struct traverse_visitbp_data {
+ /* Function arguments */
+ traverse_data_t *tv_td;
+ const dnode_phys_t *tv_dnp;
+ arc_buf_t *tv_pbuf;
+ blkptr_t *tv_bp;
+ const zbookmark_t *tv_zb;
+ /* Local variables */
+ prefetch_data_t *tv_pd;
+ zbookmark_t tv_czb;
+ arc_buf_t *tv_buf;
+ boolean_t tv_hard;
+ objset_phys_t *tv_osp;
+ dnode_phys_t *tv_ldnp;
+ blkptr_t *tv_cbp;
+ uint32_t tv_flags;
+ int tv_err;
+ int tv_lasterr;
+ int tv_i;
+ int tv_epb;
+ int tv_depth;
+} traverse_visitbp_data_t;
+
+static inline int traverse_visitbp(traverse_data_t *td, const
+ dnode_phys_t *dnp, arc_buf_t *pbuf, blkptr_t *bp, const zbookmark_t *zb);
static int traverse_dnode(traverse_data_t *td, const dnode_phys_t *dnp,
arc_buf_t *buf, uint64_t objset, uint64_t object);
zil_free(zilog);
}
-static int
-traverse_visitbp(traverse_data_t *td, const dnode_phys_t *dnp,
- arc_buf_t *pbuf, blkptr_t *bp, const zbookmark_t *zb)
+#define TRAVERSE_VISITBP_MAX_DEPTH 20
+
+static void
+__traverse_visitbp_init(traverse_visitbp_data_t *tv,
+ traverse_data_t *td, const dnode_phys_t *dnp,
+ arc_buf_t *pbuf, blkptr_t *bp, const zbookmark_t *zb, int depth)
{
- zbookmark_t czb;
- int err = 0, lasterr = 0;
- arc_buf_t *buf = NULL;
- prefetch_data_t *pd = td->td_pfd;
- boolean_t hard = td->td_flags & TRAVERSE_HARD;
+ tv->tv_td = td;
+ tv->tv_dnp = dnp;
+ tv->tv_pbuf = pbuf;
+ tv->tv_bp = bp;
+ tv->tv_zb = zb;
+ tv->tv_err = 0;
+ tv->tv_lasterr = 0;
+ tv->tv_buf = NULL;
+ tv->tv_pd = td->td_pfd;
+ tv->tv_hard = td->td_flags & TRAVERSE_HARD;
+ tv->tv_flags = ARC_WAIT;
+ tv->tv_depth = depth;
+}
- if (bp->blk_birth == 0) {
- err = td->td_func(td->td_spa, NULL, NULL, pbuf, zb, dnp,
- td->td_arg);
- return (err);
+static noinline int
+__traverse_visitbp(traverse_visitbp_data_t *tv)
+{
+ ASSERT3S(tv->tv_depth, <, TRAVERSE_VISITBP_MAX_DEPTH);
+
+ if (tv->tv_bp->blk_birth == 0) {
+ tv->tv_err = tv->tv_td->td_func(tv->tv_td->td_spa, NULL, NULL,
+ tv->tv_pbuf, tv->tv_zb, tv->tv_dnp, tv->tv_td->td_arg);
+ return (tv->tv_err);
}
- if (bp->blk_birth <= td->td_min_txg)
+ if (tv->tv_bp->blk_birth <= tv->tv_td->td_min_txg)
return (0);
- if (pd && !pd->pd_exited &&
- ((pd->pd_flags & TRAVERSE_PREFETCH_DATA) ||
- BP_GET_TYPE(bp) == DMU_OT_DNODE || BP_GET_LEVEL(bp) > 0)) {
- mutex_enter(&pd->pd_mtx);
- ASSERT(pd->pd_blks_fetched >= 0);
- while (pd->pd_blks_fetched == 0 && !pd->pd_exited)
- cv_wait(&pd->pd_cv, &pd->pd_mtx);
- pd->pd_blks_fetched--;
- cv_broadcast(&pd->pd_cv);
- mutex_exit(&pd->pd_mtx);
+ if (tv->tv_pd && !tv->tv_pd->pd_exited &&
+ ((tv->tv_pd->pd_flags & TRAVERSE_PREFETCH_DATA) ||
+ BP_GET_TYPE(tv->tv_bp) == DMU_OT_DNODE ||
+ BP_GET_LEVEL(tv->tv_bp) > 0)) {
+ mutex_enter(&tv->tv_pd->pd_mtx);
+ ASSERT(tv->tv_pd->pd_blks_fetched >= 0);
+ while (tv->tv_pd->pd_blks_fetched == 0 && !tv->tv_pd->pd_exited)
+ cv_wait(&tv->tv_pd->pd_cv, &tv->tv_pd->pd_mtx);
+ tv->tv_pd->pd_blks_fetched--;
+ cv_broadcast(&tv->tv_pd->pd_cv);
+ mutex_exit(&tv->tv_pd->pd_mtx);
}
- if (td->td_flags & TRAVERSE_PRE) {
- err = td->td_func(td->td_spa, NULL, bp, pbuf, zb, dnp,
- td->td_arg);
- if (err == TRAVERSE_VISIT_NO_CHILDREN)
+ if (tv->tv_td->td_flags & TRAVERSE_PRE) {
+ tv->tv_err = tv->tv_td->td_func(tv->tv_td->td_spa, NULL,
+ tv->tv_bp, tv->tv_pbuf, tv->tv_zb, tv->tv_dnp,
+ tv->tv_td->td_arg);
+ if (tv->tv_err == TRAVERSE_VISIT_NO_CHILDREN)
return (0);
- if (err)
- return (err);
+ if (tv->tv_err)
+ return (tv->tv_err);
}
- if (BP_GET_LEVEL(bp) > 0) {
- uint32_t flags = ARC_WAIT;
- int i;
- blkptr_t *cbp;
- int epb = BP_GET_LSIZE(bp) >> SPA_BLKPTRSHIFT;
+ if (BP_GET_LEVEL(tv->tv_bp) > 0) {
+ tv->tv_epb = BP_GET_LSIZE(tv->tv_bp) >> SPA_BLKPTRSHIFT;
- err = dsl_read(NULL, td->td_spa, bp, pbuf,
- arc_getbuf_func, &buf,
- ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb);
- if (err)
- return (err);
+ tv->tv_err = dsl_read(NULL, tv->tv_td->td_spa, tv->tv_bp,
+ tv->tv_pbuf, arc_getbuf_func, &tv->tv_buf,
+ ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL,
+ &tv->tv_flags, tv->tv_zb);
+ if (tv->tv_err)
+ return (tv->tv_err);
/* recursively visitbp() blocks below this */
- cbp = buf->b_data;
- for (i = 0; i < epb; i++, cbp++) {
- SET_BOOKMARK(&czb, zb->zb_objset, zb->zb_object,
- zb->zb_level - 1,
- zb->zb_blkid * epb + i);
- err = traverse_visitbp(td, dnp, buf, cbp, &czb);
- if (err) {
- if (!hard)
+ tv->tv_cbp = tv->tv_buf->b_data;
+ for (tv->tv_i = 0; tv->tv_i < tv->tv_epb;
+ tv->tv_i++, tv->tv_cbp++) {
+ SET_BOOKMARK(&tv->tv_czb, tv->tv_zb->zb_objset,
+ tv->tv_zb->zb_object, tv->tv_zb->zb_level - 1,
+ tv->tv_zb->zb_blkid * tv->tv_epb + tv->tv_i);
+ __traverse_visitbp_init(tv + 1, tv->tv_td,
+ tv->tv_dnp, tv->tv_buf, tv->tv_cbp,
+ &tv->tv_czb, tv->tv_depth + 1);
+ tv->tv_err = __traverse_visitbp(tv + 1);
+ if (tv->tv_err) {
+ if (!tv->tv_hard)
break;
- lasterr = err;
+ tv->tv_lasterr = tv->tv_err;
}
}
- } else if (BP_GET_TYPE(bp) == DMU_OT_DNODE) {
- uint32_t flags = ARC_WAIT;
- int i;
- int epb = BP_GET_LSIZE(bp) >> DNODE_SHIFT;
-
- err = dsl_read(NULL, td->td_spa, bp, pbuf,
- arc_getbuf_func, &buf,
- ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb);
- if (err)
- return (err);
+ } else if (BP_GET_TYPE(tv->tv_bp) == DMU_OT_DNODE) {
+ tv->tv_epb = BP_GET_LSIZE(tv->tv_bp) >> DNODE_SHIFT;
+
+ tv->tv_err = dsl_read(NULL, tv->tv_td->td_spa, tv->tv_bp,
+ tv->tv_pbuf, arc_getbuf_func, &tv->tv_buf,
+ ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL,
+ &tv->tv_flags, tv->tv_zb);
+ if (tv->tv_err)
+ return (tv->tv_err);
/* recursively visitbp() blocks below this */
- dnp = buf->b_data;
- for (i = 0; i < epb; i++, dnp++) {
- err = traverse_dnode(td, dnp, buf, zb->zb_objset,
- zb->zb_blkid * epb + i);
- if (err) {
- if (!hard)
+ tv->tv_dnp = tv->tv_buf->b_data;
+ for (tv->tv_i = 0; tv->tv_i < tv->tv_epb;
+ tv->tv_i++, tv->tv_dnp++) {
+ tv->tv_err = traverse_dnode(tv->tv_td, tv->tv_dnp,
+ tv->tv_buf, tv->tv_zb->zb_objset,
+ tv->tv_zb->zb_blkid * tv->tv_epb + tv->tv_i);
+ if (tv->tv_err) {
+ if (!tv->tv_hard)
break;
- lasterr = err;
+ tv->tv_lasterr = tv->tv_err;
}
}
- } else if (BP_GET_TYPE(bp) == DMU_OT_OBJSET) {
- uint32_t flags = ARC_WAIT;
- objset_phys_t *osp;
- dnode_phys_t *dnp;
-
- err = dsl_read_nolock(NULL, td->td_spa, bp,
- arc_getbuf_func, &buf,
- ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb);
- if (err)
- return (err);
-
- osp = buf->b_data;
- dnp = &osp->os_meta_dnode;
- err = traverse_dnode(td, dnp, buf, zb->zb_objset,
- DMU_META_DNODE_OBJECT);
- if (err && hard) {
- lasterr = err;
- err = 0;
+ } else if (BP_GET_TYPE(tv->tv_bp) == DMU_OT_OBJSET) {
+
+ tv->tv_err = dsl_read_nolock(NULL, tv->tv_td->td_spa,
+ tv->tv_bp, arc_getbuf_func, &tv->tv_buf,
+ ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL,
+ &tv->tv_flags, tv->tv_zb);
+ if (tv->tv_err)
+ return (tv->tv_err);
+
+ tv->tv_osp = tv->tv_buf->b_data;
+ tv->tv_ldnp = &tv->tv_osp->os_meta_dnode;
+ tv->tv_err = traverse_dnode(tv->tv_td, tv->tv_ldnp, tv->tv_buf,
+ tv->tv_zb->zb_objset, DMU_META_DNODE_OBJECT);
+ if (tv->tv_err && tv->tv_hard) {
+ tv->tv_lasterr = tv->tv_err;
+ tv->tv_err = 0;
}
- if (err == 0 && arc_buf_size(buf) >= sizeof (objset_phys_t)) {
- dnp = &osp->os_userused_dnode;
- err = traverse_dnode(td, dnp, buf, zb->zb_objset,
+ if (tv->tv_err == 0 &&
+ arc_buf_size(tv->tv_buf) >= sizeof (objset_phys_t)) {
+ tv->tv_ldnp = &tv->tv_osp->os_userused_dnode;
+ tv->tv_err = traverse_dnode(tv->tv_td, tv->tv_ldnp,
+ tv->tv_buf, tv->tv_zb->zb_objset,
DMU_USERUSED_OBJECT);
}
- if (err && hard) {
- lasterr = err;
- err = 0;
+ if (tv->tv_err && tv->tv_hard) {
+ tv->tv_lasterr = tv->tv_err;
+ tv->tv_err = 0;
}
- if (err == 0 && arc_buf_size(buf) >= sizeof (objset_phys_t)) {
- dnp = &osp->os_groupused_dnode;
- err = traverse_dnode(td, dnp, buf, zb->zb_objset,
+ if (tv->tv_err == 0 &&
+ arc_buf_size(tv->tv_buf) >= sizeof (objset_phys_t)) {
+ tv->tv_ldnp = &tv->tv_osp->os_groupused_dnode;
+ tv->tv_err = traverse_dnode(tv->tv_td, tv->tv_ldnp,
+ tv->tv_buf, tv->tv_zb->zb_objset,
DMU_GROUPUSED_OBJECT);
}
}
- if (buf)
- (void) arc_buf_remove_ref(buf, &buf);
+ if (tv->tv_buf)
+ (void) arc_buf_remove_ref(tv->tv_buf, &tv->tv_buf);
- if (err == 0 && lasterr == 0 && (td->td_flags & TRAVERSE_POST)) {
- err = td->td_func(td->td_spa, NULL, bp, pbuf, zb, dnp,
- td->td_arg);
+ if (tv->tv_err == 0 && tv->tv_lasterr == 0 &&
+ (tv->tv_td->td_flags & TRAVERSE_POST)) {
+ tv->tv_err = tv->tv_td->td_func(tv->tv_td->td_spa, NULL,
+ tv->tv_bp, tv->tv_pbuf, tv->tv_zb, tv->tv_dnp,
+ tv->tv_td->td_arg);
}
- return (err != 0 ? err : lasterr);
+ return (tv->tv_err != 0 ? tv->tv_err : tv->tv_lasterr);
+}
+
+/*
+ * Due to limited stack space recursive functions are frowned upon in
+ * the Linux kernel. However, they often are the most elegant solution
+ * to a problem. The following code preserves the recursive function
+ * traverse_visitbp() but moves the local variables AND function
+ * arguments to the heap to minimize the stack frame size. Enough
+ * space is initially allocated on the stack for 16 levels of recursion.
+ * This change does ugly-up-the-code but it reduces the worst case
+ * usage from roughly 2496 bytes to 576 bytes on x86_64 archs.
+ */
+static int
+traverse_visitbp(traverse_data_t *td, const dnode_phys_t *dnp,
+ arc_buf_t *pbuf, blkptr_t *bp, const zbookmark_t *zb)
+{
+ traverse_visitbp_data_t *tv;
+ int error;
+
+ tv = kmem_zalloc(sizeof(traverse_visitbp_data_t) *
+ TRAVERSE_VISITBP_MAX_DEPTH, KM_SLEEP);
+ __traverse_visitbp_init(tv, td, dnp, pbuf, bp, zb, 0);
+
+ error = __traverse_visitbp(tv);
+
+ kmem_free(tv, sizeof(traverse_visitbp_data_t) *
+ TRAVERSE_VISITBP_MAX_DEPTH);
+
+ return (error);
}
static int
traverse_impl(spa_t *spa, dsl_dataset_t *ds, blkptr_t *rootbp,
uint64_t txg_start, int flags, blkptr_cb_t func, void *arg)
{
- traverse_data_t td;
- prefetch_data_t pd = { 0 };
- zbookmark_t czb;
+ traverse_data_t *td;
+ prefetch_data_t *pd;
+ zbookmark_t *czb;
int err;
- td.td_spa = spa;
- td.td_objset = ds ? ds->ds_object : 0;
- td.td_rootbp = rootbp;
- td.td_min_txg = txg_start;
- td.td_func = func;
- td.td_arg = arg;
- td.td_pfd = &pd;
- td.td_flags = flags;
+ td = kmem_alloc(sizeof(traverse_data_t), KM_SLEEP);
+ pd = kmem_zalloc(sizeof(prefetch_data_t), KM_SLEEP);
+ czb = kmem_alloc(sizeof(zbookmark_t), KM_SLEEP);
+
+ td->td_spa = spa;
+ td->td_objset = ds ? ds->ds_object : 0;
+ td->td_rootbp = rootbp;
+ td->td_min_txg = txg_start;
+ td->td_func = func;
+ td->td_arg = arg;
+ td->td_pfd = pd;
+ td->td_flags = flags;
- pd.pd_blks_max = zfs_pd_blks_max;
- pd.pd_flags = flags;
- mutex_init(&pd.pd_mtx, NULL, MUTEX_DEFAULT, NULL);
- cv_init(&pd.pd_cv, NULL, CV_DEFAULT, NULL);
+ pd->pd_blks_max = zfs_pd_blks_max;
+ pd->pd_flags = flags;
+ mutex_init(&pd->pd_mtx, NULL, MUTEX_DEFAULT, NULL);
+ cv_init(&pd->pd_cv, NULL, CV_DEFAULT, NULL);
/* See comment on ZIL traversal in dsl_scan_visitds. */
if (ds != NULL && !dsl_dataset_is_snapshot(ds)) {
if (err)
return (err);
- traverse_zil(&td, &os->os_zil_header);
+ traverse_zil(td, &os->os_zil_header);
}
if (!(flags & TRAVERSE_PREFETCH) ||
0 == taskq_dispatch(system_taskq, traverse_prefetch_thread,
- &td, TQ_NOQUEUE))
- pd.pd_exited = B_TRUE;
+ td, TQ_NOQUEUE))
+ pd->pd_exited = B_TRUE;
- SET_BOOKMARK(&czb, td.td_objset,
+ SET_BOOKMARK(czb, td->td_objset,
ZB_ROOT_OBJECT, ZB_ROOT_LEVEL, ZB_ROOT_BLKID);
- err = traverse_visitbp(&td, NULL, NULL, rootbp, &czb);
+ err = traverse_visitbp(td, NULL, NULL, rootbp, czb);
+
+ mutex_enter(&pd->pd_mtx);
+ pd->pd_cancel = B_TRUE;
+ cv_broadcast(&pd->pd_cv);
+ while (!pd->pd_exited)
+ cv_wait(&pd->pd_cv, &pd->pd_mtx);
+ mutex_exit(&pd->pd_mtx);
- mutex_enter(&pd.pd_mtx);
- pd.pd_cancel = B_TRUE;
- cv_broadcast(&pd.pd_cv);
- while (!pd.pd_exited)
- cv_wait(&pd.pd_cv, &pd.pd_mtx);
- mutex_exit(&pd.pd_mtx);
+ mutex_destroy(&pd->pd_mtx);
+ cv_destroy(&pd->pd_cv);
- mutex_destroy(&pd.pd_mtx);
- cv_destroy(&pd.pd_cv);
+ kmem_free(czb, sizeof(zbookmark_t));
+ kmem_free(pd, sizeof(struct prefetch_data));
+ kmem_free(td, sizeof(struct traverse_data));
return (err);
}
err = 0;
return (err != 0 ? err : lasterr);
}
+
+#if defined(_KERNEL) && defined(HAVE_SPL)
+EXPORT_SYMBOL(traverse_dataset);
+EXPORT_SYMBOL(traverse_pool);
+#endif
git://git.camperquake.de / zfs.git / blobdiff