ref: 6aa266e6af166f528bce7316c59d80761284e663
parent: d6d67651e5c89df7f767705e7eb56aa2b0bb439e
author: Ori Bernstein <ori@eigenstate.org>
date: Mon Oct 25 20:29:50 EDT 2021
newblk: don't clobber refs on cached blocks
--- a/blk.c
+++ b/blk.c
@@ -553,9 +553,22 @@
if((bp = blkalloc(-1)) == -1)
return nil;
- if((b = lookupblk(bp)) == nil)
+ if((b = lookupblk(bp)) == nil){if((b = mallocz(sizeof(Blk), 1)) == nil)
return nil;
+ /*
+ * If the block is cached,
+ * then the cache holds a ref
+ * to the block, so we only
+ * want to reset the refs
+ * on an allocation.
+ *
+ * cacheblk incrmeents the
+ * refcount, so we want to
+ * start off at zero here.
+ */
+ b->ref = 0;
+ }
b->type = t;
b->flag = Bdirty;
b->bp.addr = bp;
@@ -563,7 +576,6 @@
b->bp.gen = fs->nextgen;
b->data = b->buf + Hdrsz;
- b->ref = 0; /* cacheblk incremnets */
b->nval = 0;
b->valsz = 0;
b->nbuf = 0;
@@ -606,7 +618,6 @@
return pwrite(fs->fd, b->buf, Blksz, b->bp.addr);
}
-
void
enqueue(Blk *b)
{@@ -737,12 +748,8 @@
{if(b == nil)
return;
- assert(b->ref > 0);
- rlock(b);
- if(b->flag & Bzombie && b->ref == 1)
- fprint(2, "reaping zombie: %B @ %ld\n", b->bp, b->ref);
- runlock(b);
if(adec(&b->ref) == 0){+ fprint(2, "wat: free %B @ %ld\n", b->bp, b->ref);
assert(0);
assert((b->flag & Bqueued) || !(b->flag & Bdirty));
free(b);
--
⑨