tdb2: only adjust size once when growing

[ccan] / ccan / tdb2 / free.c

diff --git a/ccan/tdb2/free.c b/ccan/tdb2/free.c
index 3917fdaa9333c4eea47fbbffa578b4068fbdaacb..48cd9c315ce02f4859ea15b0ec6de97ccde132d5 100644 (file)
--- a/ccan/tdb2/free.c
+++ b/ccan/tdb2/free.c
@@ -270,14 +270,10 @@ int add_free_record(struct tdb_context *tdb,
        return ret;
 }
 
-static size_t adjust_size(size_t keylen, size_t datalen, bool want_extra)
+static size_t adjust_size(size_t keylen, size_t datalen)
 {
        size_t size = keylen + datalen;
 
-       /* We want at least 50% growth for data. */
-       if (want_extra)
-               size += datalen/2;
-
        if (size < TDB_MIN_DATA_LEN)
                size = TDB_MIN_DATA_LEN;
 
@@ -291,13 +287,11 @@ static size_t record_leftover(size_t keylen, size_t datalen,
 {
        ssize_t leftover;
 
-       /* We might *want* extra, but not have it, so leftover is negative. */
-       leftover = total_len - adjust_size(keylen, datalen, want_extra);
-       if (leftover < (ssize_t)sizeof(struct tdb_free_record))
-               return 0;
+       if (want_extra)
+               datalen += datalen / 2;
+       leftover = total_len - adjust_size(keylen, datalen);
 
-       /* If we want extra anwyay, don't split unless we have 2x size. */
-       if (want_extra && leftover <= datalen / 2)
+       if (leftover < (ssize_t)sizeof(struct tdb_free_record))
                return 0;
 
        return leftover;
@@ -418,7 +412,7 @@ static tdb_off_t lock_and_alloc(struct tdb_context *tdb,
        tdb_off_t off, b_off,best_off;
        struct tdb_free_record pad, best = { 0 }, *r;
        double multiplier;
-       size_t size = keylen + datalen;
+       size_t size = adjust_size(keylen, datalen);
 
 again:
        b_off = bucket_off(zone_off, bucket);
@@ -494,6 +488,7 @@ again:
                leftover = record_leftover(keylen, datalen, want_extra,
                                           best.data_len);
 
+               assert(keylen + datalen + leftover <= best.data_len);
                /* We need to mark non-free before we drop lock, otherwise
                 * coalesce() could try to merge it! */
                if (set_header(tdb, &rec, keylen, datalen,
@@ -543,7 +538,7 @@ static tdb_off_t get_free(struct tdb_context *tdb,
 {
        tdb_off_t start_zone = tdb->zone_off, off;
        bool wrapped = false;
-       size_t size = adjust_size(keylen, datalen, want_extra);
+       size_t size = adjust_size(keylen, datalen);
 
        /* If they are growing, add 50% to get to higher bucket. */
        if (want_extra)
@@ -754,7 +749,7 @@ tdb_off_t alloc(struct tdb_context *tdb, size_t keylen, size_t datalen,
                if (likely(off != 0))
                        break;
 
-               if (tdb_expand(tdb, adjust_size(keylen, datalen, growing)))
+               if (tdb_expand(tdb, adjust_size(keylen, datalen)))
                        return TDB_OFF_ERR;
        }