dedup

commit 6699070ee14aa0fc3a48c52e0a146f6946e39ce5
parent d27c04494de59d32935865ca40915476d35b2c30
Author: sin <sin@2f30.org>
Date:   Fri, 26 Apr 2019 11:16:21 +0100

More gc work

Diffstat:
M
bstorage.c
 | 
51
+++++++++++++++++++++++++++++++--------------------

1 file changed, 31 insertions(+), 20 deletions(-)
diff --git a/bstorage.c b/bstorage.c
@@ -23,6 +23,7 @@
 #include "blake2.h"
 #include "block.h"
 #include "config.h"
+#include "queue.h"
 #include "tree.h"
 
 #define VMIN		0
@@ -87,13 +88,15 @@ struct bd {
 	uint64_t size;
 	uint64_t refcnt;
 	unsigned char md[MDSIZE];
-	RB_ENTRY(bd) entry;
+	RB_ENTRY(bd) rbe;
+	SLIST_ENTRY(bd) sle;
 };
 RB_HEAD(bdcache, bd);
-
+	
 /* Storage layer context */
 struct sctx {
 	struct bdcache bdcache;
+	SLIST_HEAD(gchead, bd) gchead;
 	struct bhdr bhdr;
 	int fd;
 	int rdonly;	/* when set to 1, the bssync() operation is a no-op */
@@ -111,8 +114,8 @@ bd_cmp(struct bd *b1, struct bd *b2)
 		return -1;
 	return 0;
 }
-static RB_PROTOTYPE(bdcache, bd, entry, bd_cmp)
-static RB_GENERATE(bdcache, bd, entry, bd_cmp)
+static RB_PROTOTYPE(bdcache, bd, rbe, bd_cmp)
+static RB_GENERATE(bdcache, bd, rbe, bd_cmp)
 
 static int
 bhash(void *buf, size_t n, unsigned char *md)
@@ -277,7 +280,7 @@ loadbd(struct sctx *sctx)
 	if (bd->refcnt > 0)
 		RB_INSERT(bdcache, &sctx->bdcache, bd);
 	else
-		free(bd);
+		SLIST_INSERT_HEAD(&sctx->gchead, bd, sle);
 	return 0;
 }
 
@@ -295,11 +298,18 @@ initbdcache(struct sctx *sctx)
 		if (loadbd(sctx) == 0)
 			continue;
 
-		/* Cleanup */
+		/* Free block descriptor cache */
 		RB_FOREACH_SAFE(bd, bdcache, &sctx->bdcache, tmp) {
 			RB_REMOVE(bdcache, &sctx->bdcache, bd);
 			free(bd);
 		}
+
+		/* Free garbage collector list */
+		while (!SLIST_EMPTY(&sctx->gchead)) {
+			bd = SLIST_FIRST(&sctx->gchead);
+			SLIST_REMOVE(&sctx->gchead, bd, bd, sle);
+			free(bd);
+		}
 		return -1;
 	}
 	return 0;
@@ -325,6 +335,7 @@ bscreat(struct bctx *bctx, char *path, int mode, struct bparam *bpar)
 
 	sctx = bctx->sctx;
 	RB_INIT(&sctx->bdcache);
+	SLIST_INIT(&sctx->gchead);
 	bhdr = &sctx->bhdr;
 	memcpy(bhdr->magic, BHDRMAGIC, NBHDRMAGIC);
 	bhdr->flags = (VMAJ << VMAJSHIFT) | VMIN;
@@ -380,6 +391,7 @@ bsopen(struct bctx *bctx, char *path, int flags, int mode, struct bparam *bpar)
 
 	sctx = bctx->sctx;
 	RB_INIT(&sctx->bdcache);
+	SLIST_INIT(&sctx->gchead);
 	bhdr = &sctx->bhdr;
 	if (unpackbhdr(fd, bhdr) < 0) {
 		free(sctx);
@@ -567,7 +579,7 @@ bsrm(struct bctx *bctx, unsigned char *md)
 		}
 
 		RB_REMOVE(bdcache, &sctx->bdcache, bd);
-		free(bd);
+		SLIST_INSERT_HEAD(&sctx->gchead, bd, sle);
 	}
 	return 0;
 }
@@ -579,19 +591,10 @@ bsgc(struct bctx *bctx, unsigned char *md)
 	struct bd key, *bd;
 
 	sctx = bctx->sctx;
-
-	/* Lookup block in the cache */
-	memcpy(key.md, md, MDSIZE);
-	bd = RB_FIND(bdcache, &sctx->bdcache, &key);
-	if (bd == NULL)
-		return -1;
-
-	/* Live block descriptor, nothing to do here */
-	if (bd->refcnt > 0)
-		return 0;
-
-	/* Re-punch the hole */
-	punchhole(sctx->fd, bd->offset, bd->size);
+	SLIST_FOREACH(bd, &sctx->gchead, sle) {
+		assert(bd->refcnt == 0);
+		punchhole(sctx->fd, bd->offset, bd->size);
+	}
 	return 0;
 }
 
@@ -674,11 +677,19 @@ bsclose(struct bctx *bctx)
 		return -1;
 
 	sctx = bctx->sctx;
+	/* Free block descriptor cache */
 	RB_FOREACH_SAFE(bd, bdcache, &sctx->bdcache, tmp) {
 		RB_REMOVE(bdcache, &sctx->bdcache, bd);
 		free(bd);
 	}
 
+	/* Free garbage collector list */
+	while (!SLIST_EMPTY(&sctx->gchead)) {
+		bd = SLIST_FIRST(&sctx->gchead);
+		SLIST_REMOVE(&sctx->gchead, bd, bd, sle);
+		free(bd);
+	}
+
 	r = close(sctx->fd);
 	free(sctx);
 	return r;