Improve L2 caching control for prefetched indirects
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dbuf_prefetch_impl() should look on level of current indirect, not
the target prefetch level.  dbuf_prefetch_indirect_done() should
call dnode_level_is_l2cacheable() if we have dpa_dnode to pass it.
It should fix some both false positive and negative L2ARC caching.

While there, fix redacted feature activation assertions.  One was
always true, while another could give false positive if dpa_dnode
is NULL.

George Amanakis <gamanakis@gmail.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #17204
This commit is contained in:
Alexander Motin 2025-04-08 19:43:32 -04:00 committed by GitHub
parent 8f08dbfbe1
commit a497c5fc8b
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@ -3560,12 +3560,9 @@ dbuf_issue_final_prefetch_done(zio_t *zio, const zbookmark_phys_t *zb,
static void
dbuf_issue_final_prefetch(dbuf_prefetch_arg_t *dpa, blkptr_t *bp)
{
ASSERT(!BP_IS_REDACTED(bp) ||
dsl_dataset_feature_is_active(
dpa->dpa_dnode->dn_objset->os_dsl_dataset,
SPA_FEATURE_REDACTED_DATASETS));
if (BP_IS_HOLE(bp) || BP_IS_EMBEDDED(bp) || BP_IS_REDACTED(bp))
ASSERT(!BP_IS_HOLE(bp));
ASSERT(!BP_IS_REDACTED(bp));
if (BP_IS_EMBEDDED(bp))
return (dbuf_prefetch_fini(dpa, B_FALSE));
int zio_flags = ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE;
@ -3651,10 +3648,10 @@ dbuf_prefetch_indirect_done(zio_t *zio, const zbookmark_phys_t *zb,
blkptr_t *bp = ((blkptr_t *)abuf->b_data) +
P2PHASE(nextblkid, 1ULL << dpa->dpa_epbs);
ASSERT(!BP_IS_REDACTED(bp) || (dpa->dpa_dnode &&
ASSERT(!BP_IS_REDACTED(bp) || dpa->dpa_dnode == NULL ||
dsl_dataset_feature_is_active(
dpa->dpa_dnode->dn_objset->os_dsl_dataset,
SPA_FEATURE_REDACTED_DATASETS)));
SPA_FEATURE_REDACTED_DATASETS));
if (BP_IS_HOLE(bp) || BP_IS_REDACTED(bp)) {
arc_buf_destroy(abuf, private);
dbuf_prefetch_fini(dpa, B_TRUE);
@ -3667,8 +3664,14 @@ dbuf_prefetch_indirect_done(zio_t *zio, const zbookmark_phys_t *zb,
zbookmark_phys_t zb;
/* flag if L2ARC eligible, l2arc_noprefetch then decides */
if (dpa->dpa_aflags & ARC_FLAG_L2CACHE)
iter_aflags |= ARC_FLAG_L2CACHE;
if (dpa->dpa_dnode) {
if (dnode_level_is_l2cacheable(bp, dpa->dpa_dnode,
dpa->dpa_curlevel))
iter_aflags |= ARC_FLAG_L2CACHE;
} else {
if (dpa->dpa_aflags & ARC_FLAG_L2CACHE)
iter_aflags |= ARC_FLAG_L2CACHE;
}
ASSERT3U(dpa->dpa_curlevel, ==, BP_GET_LEVEL(bp));
@ -3807,7 +3810,7 @@ dbuf_prefetch_impl(dnode_t *dn, int64_t level, uint64_t blkid,
zbookmark_phys_t zb;
/* flag if L2ARC eligible, l2arc_noprefetch then decides */
if (dnode_level_is_l2cacheable(&bp, dn, level))
if (dnode_level_is_l2cacheable(&bp, dn, curlevel))
iter_aflags |= ARC_FLAG_L2CACHE;
SET_BOOKMARK(&zb, ds != NULL ? ds->ds_object : DMU_META_OBJSET,