fellow_busy: Add a mempool

Unfortunately, this brings us above 4K, so we fill up with io structs

src/fellow_cache.c

@@ -687,6 +687,11 @@ struct fellow_busy_io_seglist {
 	struct buddy_off_extent reg;
 };
 
+// pool for segment memory
+BUDDY_POOL(fbo_segmem, 1);
+//BUDDY_POOL_GET_FUNC(fbo_segmem, static)
+//BUDDY_POOL_AVAIL_FUNC(fbo_segmem, static)
+
 struct fellow_busy_io {
 	uint16_t				magic;
 #define FELLOW_BUSY_IO_MAGIC			0x0bcb
@@ -727,13 +732,15 @@ struct fellow_busy {
 	struct fellow_cache_seg	*body_seg;
 	struct fellow_body_region	body_region;
 
+	struct fbo_segmem		segmem[1];
+
 #define FCO_MAX_REGIONS ((FELLOW_DISK_LOG_BLOCK_ENTRIES - 1) * DLE_REG_NREGION)
 // for fdsl and busy region last chance
 #define FCO_REGIONS_RESERVE 3
 	struct buddy_off_extent	region[FCO_MAX_REGIONS];
 	unsigned			nregion;
 	uint8_t				grown;
-#define FBO_NIO 11
+#define FBO_NIO 100
 	/* protected by fco mtx */
 	uint8_t				io_idx;
 	uint8_t				io_outstanding;
@@ -2014,6 +2021,21 @@ fellow_cache_obj_new(
 	return (fcr);
 }
 
+static void
+fellow_busy_fill_segmem(struct buddy_reqs *reqs, const void *priv)
+{
+	const struct stvfe_tune *tune;
+	unsigned u, bits;
+
+	CHECK_OBJ_NOTNULL(reqs, BUDDY_REQS_MAGIC);
+	CAST_OBJ_NOTNULL(tune, priv, STVFE_TUNE_MAGIC);
+
+	bits = tune->chunk_exponent;
+
+	for (u = 0; u < reqs->space; u++)
+		AN(buddy_req_page(reqs, bits, 0));
+}
+
 struct fellow_cache_res
 fellow_busy_obj_alloc(struct fellow_cache *fc,
     struct fellow_cache_obj **fcop, uintptr_t *priv2,
@@ -2140,6 +2162,9 @@ fellow_busy_obj_alloc(struct fellow_cache *fc,
 	 */
 	fbo->io_outstanding = 1;
 
+	BUDDY_POOL_INIT(fbo->segmem, fc->membuddy, FEP_SPC,
+	    fellow_busy_fill_segmem, fc->tune);
+
 	return (FCR_OK(fbo));
 }
 
@@ -4723,6 +4748,8 @@ fellow_busy_done(struct fellow_busy *fbo, struct objcore *oc, unsigned inlog)
 	fc = fbo->fc;
 	CHECK_OBJ_NOTNULL(fc, FELLOW_CACHE_MAGIC);
 
+	BUDDY_POOL_FINI(fbo->segmem);
+
 	// nicer way?
 	if (fbo->body_seg != NULL)
 		fellow_busy_obj_trimstore(fbo);
@@ -6562,7 +6589,7 @@ main(int argc, char **argv)
 		fn = argv[1];
 
 	DBG("fellow_busy %zu", sizeof(struct fellow_busy));
-	assert(sizeof(struct fellow_busy) <= MIN_FELLOW_BLOCK);
+	assert(sizeof(struct fellow_busy) <= 2 * MIN_FELLOW_BLOCK);
 
 	t_tailq_concat();