X-Git-Url: https://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftdb2%2Ffree.c;h=ba14dfcd70747b8ad6789ba08487d30b91cbc6fc;hp=816d0ee540b3fe81f9fa2f8c4f40561442aab732;hb=fc00f14087f911da23d1d89e02705c498447db22;hpb=fe55330a60e4e14ea6cac2ff40d50eddca4cf140 diff --git a/ccan/tdb2/free.c b/ccan/tdb2/free.c index 816d0ee5..ba14dfcd 100644 --- a/ccan/tdb2/free.c +++ b/ccan/tdb2/free.c @@ -49,24 +49,24 @@ unsigned int size_to_bucket(tdb_len_t data_len) return bucket; } -tdb_off_t first_flist(struct tdb_context *tdb) +tdb_off_t first_ftable(struct tdb_context *tdb) { - return tdb_read_off(tdb, offsetof(struct tdb_header, free_list)); + return tdb_read_off(tdb, offsetof(struct tdb_header, free_table)); } -tdb_off_t next_flist(struct tdb_context *tdb, tdb_off_t flist) +tdb_off_t next_ftable(struct tdb_context *tdb, tdb_off_t ftable) { - return tdb_read_off(tdb, flist + offsetof(struct tdb_freelist, next)); + return tdb_read_off(tdb, ftable + offsetof(struct tdb_freetable,next)); } -int tdb_flist_init(struct tdb_context *tdb) +int tdb_ftable_init(struct tdb_context *tdb) { /* Use reservoir sampling algorithm to select a free list at random. */ unsigned int rnd, max = 0, count = 0; tdb_off_t off; - tdb->flist_off = off = first_flist(tdb); - tdb->flist = 0; + tdb->ftable_off = off = first_ftable(tdb); + tdb->ftable = 0; while (off) { if (off == TDB_OFF_ERR) @@ -74,38 +74,38 @@ int tdb_flist_init(struct tdb_context *tdb) rnd = random(); if (rnd >= max) { - tdb->flist_off = off; - tdb->flist = count; + tdb->ftable_off = off; + tdb->ftable = count; max = rnd; } - off = next_flist(tdb, off); + off = next_ftable(tdb, off); count++; } return 0; } /* Offset of a given bucket. */ -tdb_off_t bucket_off(tdb_off_t flist_off, unsigned bucket) +tdb_off_t bucket_off(tdb_off_t ftable_off, unsigned bucket) { - return flist_off + offsetof(struct tdb_freelist, buckets) + return ftable_off + offsetof(struct tdb_freetable, buckets) + bucket * sizeof(tdb_off_t); } /* Returns free_buckets + 1, or list number to search. */ static tdb_off_t find_free_head(struct tdb_context *tdb, - tdb_off_t flist_off, + tdb_off_t ftable_off, tdb_off_t bucket) { /* Speculatively search for a non-zero bucket. */ - return tdb_find_nonzero_off(tdb, bucket_off(flist_off, 0), + return tdb_find_nonzero_off(tdb, bucket_off(ftable_off, 0), bucket, TDB_FREE_BUCKETS); } /* Remove from free bucket. */ static int remove_from_list(struct tdb_context *tdb, tdb_off_t b_off, tdb_off_t r_off, - struct tdb_free_record *r) + const struct tdb_free_record *r) { tdb_off_t off; @@ -116,10 +116,10 @@ static int remove_from_list(struct tdb_context *tdb, off = frec_prev(r) + offsetof(struct tdb_free_record, next); } -#ifdef DEBUG +#ifdef CCAN_TDB2_DEBUG if (tdb_read_off(tdb, off) != r_off) { - tdb->log(tdb, TDB_DEBUG_FATAL, tdb->log_priv, - "remove_from_list: %llu bad prev in list %llu\n", + tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_DEBUG_FATAL, + "remove_from_list: %llu bad prev in list %llu", (long long)r_off, (long long)b_off); return -1; } @@ -134,11 +134,11 @@ static int remove_from_list(struct tdb_context *tdb, off = r->next + offsetof(struct tdb_free_record,magic_and_prev); /* r->next->prev = r->prev */ -#ifdef DEBUG +#ifdef CCAN_TDB2_DEBUG if (tdb_read_off(tdb, off) & TDB_OFF_MASK != r_off) { - tdb->log(tdb, TDB_DEBUG_FATAL, tdb->log_priv, - "remove_from_list: %llu bad list %llu\n", - (long long)r_off, (long long)b_off); + tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_DEBUG_FATAL, + "remove_from_list: %llu bad list %llu", + (long long)r_off, (long long)b_off); return -1; } #endif @@ -159,8 +159,8 @@ static int enqueue_in_free(struct tdb_context *tdb, struct tdb_free_record new; uint64_t magic = (TDB_FREE_MAGIC << (64 - TDB_OFF_UPPER_STEAL)); - /* We only need to set flist_and_len; rest is set in enqueue_in_free */ - new.flist_and_len = ((uint64_t)tdb->flist << (64 - TDB_OFF_UPPER_STEAL)) + /* We only need to set ftable_and_len; rest is set in enqueue_in_free */ + new.ftable_and_len = ((uint64_t)tdb->ftable << (64 - TDB_OFF_UPPER_STEAL)) | len; /* prev = 0. */ new.magic_and_prev = magic; @@ -171,14 +171,15 @@ static int enqueue_in_free(struct tdb_context *tdb, return -1; if (new.next) { -#ifdef DEBUG +#ifdef CCAN_TDB2_DEBUG if (tdb_read_off(tdb, new.next + offsetof(struct tdb_free_record, magic_and_prev)) != magic) { - tdb->log(tdb, TDB_DEBUG_FATAL, tdb->log_priv, - "enqueue_in_free: %llu bad head prev %llu\n", - (long long)new.next, (long long)b_off); + tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_DEBUG_FATAL, + "enqueue_in_free: %llu bad head" + " prev %llu", + (long long)new.next, (long long)b_off); return -1; } #endif @@ -208,7 +209,7 @@ int add_free_record(struct tdb_context *tdb, len = len_with_header - sizeof(struct tdb_used_record); - b_off = bucket_off(tdb->flist_off, size_to_bucket(len)); + b_off = bucket_off(tdb->ftable_off, size_to_bucket(len)); if (tdb_lock_free_bucket(tdb, b_off, TDB_LOCK_WAIT) != 0) return -1; @@ -244,14 +245,17 @@ static size_t record_leftover(size_t keylen, size_t datalen, return leftover; } -/* FIXME: Shortcut common case where tdb->flist == flist */ -static tdb_off_t flist_offset(struct tdb_context *tdb, unsigned int flist) +static tdb_off_t ftable_offset(struct tdb_context *tdb, unsigned int ftable) { - tdb_off_t off = first_flist(tdb); + tdb_off_t off; unsigned int i; - for (i = 0; i < flist; i++) - off = next_flist(tdb, off); + if (likely(tdb->ftable == ftable)) + return tdb->ftable_off; + + off = first_ftable(tdb); + for (i = 0; i < ftable; i++) + off = next_ftable(tdb, off); return off; } @@ -259,27 +263,31 @@ static tdb_off_t flist_offset(struct tdb_context *tdb, unsigned int flist) static int coalesce(struct tdb_context *tdb, tdb_off_t off, tdb_off_t b_off, tdb_len_t data_len) { - struct tdb_free_record pad, *r; tdb_off_t end; + struct tdb_free_record rec; add_stat(tdb, alloc_coalesce_tried, 1); end = off + sizeof(struct tdb_used_record) + data_len; while (end < tdb->map_size) { + const struct tdb_free_record *r; tdb_off_t nb_off; - unsigned flist, bucket; + unsigned ftable, bucket; - /* FIXME: do tdb_get here and below really win? */ - r = tdb_get(tdb, end, &pad, sizeof(pad)); + r = tdb_access_read(tdb, end, sizeof(*r), true); if (!r) goto err; - if (frec_magic(r) != TDB_FREE_MAGIC) + if (frec_magic(r) != TDB_FREE_MAGIC + || frec_ftable(r) == TDB_FTABLE_NONE) { + tdb_access_release(tdb, r); break; + } - flist = frec_flist(r); + ftable = frec_ftable(r); bucket = size_to_bucket(frec_len(r)); - nb_off = bucket_off(flist_offset(tdb, flist), bucket); + nb_off = bucket_off(ftable_offset(tdb, ftable), bucket); + tdb_access_release(tdb, r); /* We may be violating lock order here, so best effort. */ if (tdb_lock_free_bucket(tdb, nb_off, TDB_LOCK_NOWAIT) == -1) { @@ -288,31 +296,30 @@ static int coalesce(struct tdb_context *tdb, } /* Now we have lock, re-check. */ - r = tdb_get(tdb, end, &pad, sizeof(pad)); - if (!r) { + if (tdb_read_convert(tdb, end, &rec, sizeof(rec))) { tdb_unlock_free_bucket(tdb, nb_off); goto err; } - if (unlikely(frec_magic(r) != TDB_FREE_MAGIC)) { + if (unlikely(frec_magic(&rec) != TDB_FREE_MAGIC)) { add_stat(tdb, alloc_coalesce_race, 1); tdb_unlock_free_bucket(tdb, nb_off); break; } - if (unlikely(frec_flist(r) != flist) - || unlikely(size_to_bucket(frec_len(r)) != bucket)) { + if (unlikely(frec_ftable(&rec) != ftable) + || unlikely(size_to_bucket(frec_len(&rec)) != bucket)) { add_stat(tdb, alloc_coalesce_race, 1); tdb_unlock_free_bucket(tdb, nb_off); break; } - if (remove_from_list(tdb, nb_off, end, r) == -1) { + if (remove_from_list(tdb, nb_off, end, &rec) == -1) { tdb_unlock_free_bucket(tdb, nb_off); goto err; } - end += sizeof(struct tdb_used_record) + frec_len(r); + end += sizeof(struct tdb_used_record) + frec_len(&rec); tdb_unlock_free_bucket(tdb, nb_off); add_stat(tdb, alloc_coalesce_num_merged, 1); } @@ -321,32 +328,27 @@ static int coalesce(struct tdb_context *tdb, if (end == off + sizeof(struct tdb_used_record) + data_len) return 0; - /* OK, expand record */ - r = tdb_get(tdb, off, &pad, sizeof(pad)); - if (!r) + /* OK, expand initial record */ + if (tdb_read_convert(tdb, off, &rec, sizeof(rec))) goto err; - if (frec_len(r) != data_len) { - tdb->ecode = TDB_ERR_CORRUPT; - tdb->log(tdb, TDB_DEBUG_FATAL, tdb->log_priv, - "coalesce: expected data len %llu not %llu\n", - (long long)data_len, (long long)frec_len(r)); + if (frec_len(&rec) != data_len) { + tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_DEBUG_FATAL, + "coalesce: expected data len %zu not %zu", + (size_t)data_len, (size_t)frec_len(&rec)); goto err; } - if (remove_from_list(tdb, b_off, off, r) == -1) - goto err; - - r = tdb_access_write(tdb, off, sizeof(*r), true); - if (!r) + if (remove_from_list(tdb, b_off, off, &rec) == -1) goto err; /* We have to drop this to avoid deadlocks, so make sure record * doesn't get coalesced by someone else! */ - r->magic_and_prev = TDB_COALESCING_MAGIC << (64 - TDB_OFF_UPPER_STEAL); - /* FIXME: Use 255 as invalid free list? */ - r->flist_and_len = end - off - sizeof(struct tdb_used_record); - if (tdb_access_commit(tdb, r) != 0) + rec.ftable_and_len = (TDB_FTABLE_NONE << (64 - TDB_OFF_UPPER_STEAL)) + | (end - off - sizeof(struct tdb_used_record)); + if (tdb_write_off(tdb, off + offsetof(struct tdb_free_record, + ftable_and_len), + rec.ftable_and_len) != 0) goto err; add_stat(tdb, alloc_coalesce_succeeded, 1); @@ -364,20 +366,21 @@ err: /* We need size bytes to put our key and data in. */ static tdb_off_t lock_and_alloc(struct tdb_context *tdb, - tdb_off_t flist_off, + tdb_off_t ftable_off, tdb_off_t bucket, size_t keylen, size_t datalen, bool want_extra, + unsigned magic, unsigned hashlow) { tdb_off_t off, b_off,best_off; - struct tdb_free_record pad, best = { 0 }, *r; + struct tdb_free_record best = { 0 }; double multiplier; size_t size = adjust_size(keylen, datalen); add_stat(tdb, allocs, 1); again: - b_off = bucket_off(flist_off, bucket); + b_off = bucket_off(ftable_off, bucket); /* FIXME: Try non-blocking wait first, to measure contention. */ /* Lock this bucket. */ @@ -385,7 +388,7 @@ again: return TDB_OFF_ERR; } - best.flist_and_len = -1ULL; + best.ftable_and_len = -1ULL; best_off = 0; /* Get slack if we're after extra. */ @@ -401,14 +404,18 @@ again: goto unlock_err; while (off) { - /* FIXME: Does tdb_get win anything here? */ - r = tdb_get(tdb, off, &pad, sizeof(*r)); + const struct tdb_free_record *r; + tdb_len_t len; + tdb_off_t next; + + r = tdb_access_read(tdb, off, sizeof(*r), true); if (!r) goto unlock_err; if (frec_magic(r) != TDB_FREE_MAGIC) { - tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv, - "lock_and_alloc: %llu non-free 0x%llx\n", + tdb_access_release(tdb, r); + tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_DEBUG_FATAL, + "lock_and_alloc: %llu non-free 0x%llx", (long long)off, (long long)r->magic_and_prev); goto unlock_err; } @@ -418,13 +425,19 @@ again: best = *r; } - if (frec_len(&best) < size * multiplier && best_off) + if (frec_len(&best) < size * multiplier && best_off) { + tdb_access_release(tdb, r); break; + } multiplier *= 1.01; + next = r->next; + len = frec_len(r); + tdb_access_release(tdb, r); + /* Since we're going slow anyway, try coalescing here. */ - switch (coalesce(tdb, off, b_off, frec_len(r))) { + switch (coalesce(tdb, off, b_off, len)) { case -1: /* This has already unlocked on error. */ return -1; @@ -432,7 +445,7 @@ again: /* This has unlocked list, restart. */ goto again; } - off = r->next; + off = next; } /* If we found anything at all, use it. */ @@ -450,9 +463,8 @@ again: assert(keylen + datalen + leftover <= frec_len(&best)); /* We need to mark non-free before we drop lock, otherwise * coalesce() could try to merge it! */ - if (set_used_header(tdb, &rec, keylen, datalen, - frec_len(&best) - leftover, - hashlow) != 0) + if (set_header(tdb, &rec, magic, keylen, datalen, + frec_len(&best) - leftover, hashlow) != 0) goto unlock_err; if (tdb_write_convert(tdb, best_off, &rec, sizeof(rec)) != 0) @@ -484,10 +496,10 @@ unlock_err: /* Get a free block from current free list, or 0 if none. */ static tdb_off_t get_free(struct tdb_context *tdb, size_t keylen, size_t datalen, bool want_extra, - unsigned hashlow) + unsigned magic, unsigned hashlow) { - tdb_off_t off, flist_off; - unsigned start_b, b, flist; + tdb_off_t off, ftable_off; + unsigned start_b, b, ftable; bool wrapped = false; /* If they are growing, add 50% to get to higher bucket. */ @@ -497,17 +509,17 @@ static tdb_off_t get_free(struct tdb_context *tdb, else start_b = size_to_bucket(adjust_size(keylen, datalen)); - flist_off = tdb->flist_off; - flist = tdb->flist; - while (!wrapped || flist_off != tdb->flist_off) { + ftable_off = tdb->ftable_off; + ftable = tdb->ftable; + while (!wrapped || ftable_off != tdb->ftable_off) { /* Start at exact size bucket, and search up... */ - for (b = find_free_head(tdb, flist_off, start_b); + for (b = find_free_head(tdb, ftable_off, start_b); b < TDB_FREE_BUCKETS; - b = find_free_head(tdb, flist_off, b + 1)) { + b = find_free_head(tdb, ftable_off, b + 1)) { /* Try getting one from list. */ - off = lock_and_alloc(tdb, flist_off, + off = lock_and_alloc(tdb, ftable_off, b, keylen, datalen, want_extra, - hashlow); + magic, hashlow); if (off == TDB_OFF_ERR) return TDB_OFF_ERR; if (off != 0) { @@ -516,31 +528,31 @@ static tdb_off_t get_free(struct tdb_context *tdb, if (b == TDB_FREE_BUCKETS - 1) add_stat(tdb, alloc_bucket_max, 1); /* Worked? Stay using this list. */ - tdb->flist_off = flist_off; - tdb->flist = flist; + tdb->ftable_off = ftable_off; + tdb->ftable = ftable; return off; } /* Didn't work. Try next bucket. */ } - /* Hmm, try next list. */ - flist_off = next_flist(tdb, flist_off); - flist++; + /* Hmm, try next table. */ + ftable_off = next_ftable(tdb, ftable_off); + ftable++; - if (flist_off == 0) { + if (ftable_off == 0) { wrapped = true; - flist_off = first_flist(tdb); - flist = 0; + ftable_off = first_ftable(tdb); + ftable = 0; } } return 0; } -int set_used_header(struct tdb_context *tdb, - struct tdb_used_record *rec, - uint64_t keylen, uint64_t datalen, - uint64_t actuallen, unsigned hashlow) +int set_header(struct tdb_context *tdb, + struct tdb_used_record *rec, + unsigned magic, uint64_t keylen, uint64_t datalen, + uint64_t actuallen, unsigned hashlow) { uint64_t keybits = (fls64(keylen) + 1) / 2; @@ -548,16 +560,15 @@ int set_used_header(struct tdb_context *tdb, rec->magic_and_meta = (hashlow & ((1 << 11)-1)) | ((actuallen - (keylen + datalen)) << 11) | (keybits << 43) - | (TDB_MAGIC << 48); + | ((uint64_t)magic << 48); rec->key_and_data_len = (keylen | (datalen << (keybits*2))); /* Encoding can fail on big values. */ if (rec_key_length(rec) != keylen || rec_data_length(rec) != datalen || rec_extra_padding(rec) != actuallen - (keylen + datalen)) { - tdb->ecode = TDB_ERR_IO; - tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv, - "Could not encode k=%llu,d=%llu,a=%llu\n", + tdb_logerr(tdb, TDB_ERR_IO, TDB_DEBUG_ERROR, + "Could not encode k=%llu,d=%llu,a=%llu", (long long)keylen, (long long)datalen, (long long)actuallen); return -1; @@ -577,8 +588,8 @@ static int tdb_expand(struct tdb_context *tdb, tdb_len_t size) /* Need to hold a hash lock to expand DB: transactions rely on it. */ if (!(tdb->flags & TDB_NOLOCK) && !tdb->allrecord_lock.count && !tdb_has_hash_locks(tdb)) { - tdb->log(tdb, TDB_DEBUG_FATAL, tdb->log_priv, - "tdb_expand: must hold lock during expand\n"); + tdb_logerr(tdb, TDB_ERR_LOCK, TDB_DEBUG_ERROR, + "tdb_expand: must hold lock during expand"); return -1; } @@ -616,7 +627,7 @@ static int tdb_expand(struct tdb_context *tdb, tdb_len_t size) /* This won't fail: it will expand the database if it has to. */ tdb_off_t alloc(struct tdb_context *tdb, size_t keylen, size_t datalen, - uint64_t hash, bool growing) + uint64_t hash, unsigned magic, bool growing) { tdb_off_t off; @@ -624,7 +635,7 @@ tdb_off_t alloc(struct tdb_context *tdb, size_t keylen, size_t datalen, assert(!tdb->direct_access); for (;;) { - off = get_free(tdb, keylen, datalen, growing, hash); + off = get_free(tdb, keylen, datalen, growing, magic, hash); if (likely(off != 0)) break;