Illumos #3137 L2ARC compression

[zfs.git] / module / zfs / dbuf.c

diff --git a/module/zfs/dbuf.c b/module/zfs/dbuf.c
index 1f6fa93..faa6cc3 100644 (file)
--- a/module/zfs/dbuf.c
+++ b/module/zfs/dbuf.c
@@ -21,6 +21,8 @@
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
+ * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
  */
 
 #include <sys/zfs_context.h>
@@ -260,7 +262,7 @@ dbuf_is_metadata(dmu_buf_impl_t *db)
                boolean_t is_metadata;
 
                DB_DNODE_ENTER(db);
-               is_metadata = dmu_ot[DB_DNODE(db)->dn_type].ot_metadata;
+               is_metadata = DMU_OT_IS_METADATA(DB_DNODE(db)->dn_type);
                DB_DNODE_EXIT(db);
 
                return (is_metadata);
@@ -372,7 +374,7 @@ dbuf_verify(dmu_buf_impl_t *db)
        } else if (db->db_blkid == DMU_SPILL_BLKID) {
                ASSERT(dn != NULL);
                ASSERT3U(db->db.db_size, >=, dn->dn_bonuslen);
-               ASSERT3U(db->db.db_offset, ==, 0);
+               ASSERT0(db->db.db_offset);
        } else {
                ASSERT3U(db->db.db_offset, ==, db->db_blkid * db->db.db_size);
        }
@@ -558,7 +560,6 @@ dbuf_read_impl(dmu_buf_impl_t *db, zio_t *zio, uint32_t *flags)
        spa_t *spa;
        zbookmark_t zb;
        uint32_t aflags = ARC_NOWAIT;
-       arc_buf_t *pbuf;
 
        DB_DNODE_ENTER(db);
        dn = DB_DNODE(db);
@@ -614,20 +615,16 @@ dbuf_read_impl(dmu_buf_impl_t *db, zio_t *zio, uint32_t *flags)
 
        if (DBUF_IS_L2CACHEABLE(db))
                aflags |= ARC_L2CACHE;
+       if (DBUF_IS_L2COMPRESSIBLE(db))
+               aflags |= ARC_L2COMPRESS;
 
        SET_BOOKMARK(&zb, db->db_objset->os_dsl_dataset ?
            db->db_objset->os_dsl_dataset->ds_object : DMU_META_OBJSET,
            db->db.db_object, db->db_level, db->db_blkid);
 
        dbuf_add_ref(db, NULL);
-       /* ZIO_FLAG_CANFAIL callers have to check the parent zio's error */
 
-       if (db->db_parent)
-               pbuf = db->db_parent->db_buf;
-       else
-               pbuf = db->db_objset->os_phys_buf;
-
-       (void) dsl_read(zio, spa, db->db_blkptr, pbuf,
+       (void) arc_read(zio, spa, db->db_blkptr,
            dbuf_read_done, db, ZIO_PRIORITY_SYNC_READ,
            (*flags & DB_RF_CANFAIL) ? ZIO_FLAG_CANFAIL : ZIO_FLAG_MUSTSUCCEED,
            &aflags, &zb);
@@ -1025,7 +1022,6 @@ void
 dbuf_release_bp(dmu_buf_impl_t *db)
 {
        objset_t *os;
-       zbookmark_t zb;
 
        DB_GET_OBJSET(&os, db);
        ASSERT(dsl_pool_sync_context(dmu_objset_pool(os)));
@@ -1033,13 +1029,7 @@ dbuf_release_bp(dmu_buf_impl_t *db)
            list_link_active(&os->os_dsl_dataset->ds_synced_link));
        ASSERT(db->db_parent == NULL || arc_released(db->db_parent->db_buf));
 
-       zb.zb_objset = os->os_dsl_dataset ?
-           os->os_dsl_dataset->ds_object : 0;
-       zb.zb_object = db->db.db_object;
-       zb.zb_level = db->db_level;
-       zb.zb_blkid = db->db_blkid;
-       (void) arc_release_bp(db->db_buf, db,
-           db->db_blkptr, os->os_spa, &zb);
+       (void) arc_release(db->db_buf, db);
 }
 
 dbuf_dirty_record_t *
@@ -1885,7 +1875,6 @@ dbuf_prefetch(dnode_t *dn, uint64_t blkid)
                if (bp && !BP_IS_HOLE(bp)) {
                        int priority = dn->dn_type == DMU_OT_DDT_ZAP ?
                            ZIO_PRIORITY_DDT_PREFETCH : ZIO_PRIORITY_ASYNC_READ;
-                       arc_buf_t *pbuf;
                        dsl_dataset_t *ds = dn->dn_objset->os_dsl_dataset;
                        uint32_t aflags = ARC_NOWAIT | ARC_PREFETCH;
                        zbookmark_t zb;
@@ -1893,13 +1882,8 @@ dbuf_prefetch(dnode_t *dn, uint64_t blkid)
                        SET_BOOKMARK(&zb, ds ? ds->ds_object : DMU_META_OBJSET,
                            dn->dn_object, 0, blkid);
 
-                       if (db)
-                               pbuf = db->db_buf;
-                       else
-                               pbuf = dn->dn_objset->os_phys_buf;
-
-                       (void) dsl_read(NULL, dn->dn_objset->os_spa,
-                           bp, pbuf, NULL, NULL, priority,
+                       (void) arc_read(NULL, dn->dn_objset->os_spa,
+                           bp, NULL, NULL, priority,
                            ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE,
                            &aflags, &zb);
                }
@@ -2188,7 +2172,24 @@ dbuf_rele_and_unlock(dmu_buf_impl_t *db, void *tag)
                        dbuf_evict(db);
                } else {
                        VERIFY(arc_buf_remove_ref(db->db_buf, db) == 0);
-                       if (!DBUF_IS_CACHEABLE(db))
+
+                       /*
+                        * A dbuf will be eligible for eviction if either the
+                        * 'primarycache' property is set or a duplicate
+                        * copy of this buffer is already cached in the arc.
+                        *
+                        * In the case of the 'primarycache' a buffer
+                        * is considered for eviction if it matches the
+                        * criteria set in the property.
+                        *
+                        * To decide if our buffer is considered a
+                        * duplicate, we must call into the arc to determine
+                        * if multiple buffers are referencing the same
+                        * block on-disk. If so, then we simply evict
+                        * ourselves.
+                        */
+                       if (!DBUF_IS_CACHEABLE(db) ||
+                           arc_buf_eviction_needed(db->db_buf))
                                dbuf_clear(db);
                        else
                                mutex_exit(&db->db_mtx);
@@ -2415,7 +2416,7 @@ dbuf_sync_leaf(dbuf_dirty_record_t *dr, dmu_tx_t *tx)
                dbuf_dirty_record_t **drp;
 
                ASSERT(*datap != NULL);
-               ASSERT3U(db->db_level, ==, 0);
+               ASSERT0(db->db_level);
                ASSERT3U(dn->dn_phys->dn_bonuslen, <=, DN_MAX_BONUSLEN);
                bcopy(*datap, DN_BONUS(dn->dn_phys), dn->dn_phys->dn_bonuslen);
                DB_DNODE_EXIT(db);
@@ -2618,7 +2619,7 @@ dbuf_write_done(zio_t *zio, arc_buf_t *buf, void *vdb)
        uint64_t txg = zio->io_txg;
        dbuf_dirty_record_t **drp, *dr;
 
-       ASSERT3U(zio->io_error, ==, 0);
+       ASSERT0(zio->io_error);
        ASSERT(db->db_blkptr == bp);
 
        if (zio->io_flags & ZIO_FLAG_IO_REWRITE) {
@@ -2824,9 +2825,10 @@ dbuf_write(dbuf_dirty_record_t *dr, arc_buf_t *data, dmu_tx_t *tx)
        } else {
                ASSERT(arc_released(data));
                dr->dr_zio = arc_write(zio, os->os_spa, txg,
-                   db->db_blkptr, data, DBUF_IS_L2CACHEABLE(db), &zp,
-                   dbuf_write_ready, dbuf_write_done, db,
-                   ZIO_PRIORITY_ASYNC_WRITE, ZIO_FLAG_MUSTSUCCEED, &zb);
+                   db->db_blkptr, data, DBUF_IS_L2CACHEABLE(db),
+                   DBUF_IS_L2COMPRESSIBLE(db), &zp, dbuf_write_ready,
+                   dbuf_write_done, db, ZIO_PRIORITY_ASYNC_WRITE,
+                   ZIO_FLAG_MUSTSUCCEED, &zb);
        }
 }