cleanup, comments

src/vslp_dir.c

@@ -50,6 +50,7 @@ typedef int (*compar)( const void*, const void* );
 struct vslp_state {
 	struct vslpdir *vslpd;
 	struct vbitmap *picklist;
+	/* start index in the hashcircle for our key */
 	int idx;
 	const struct vrt_ctx *ctx;
 };
@@ -391,6 +392,9 @@ vslpdir_any_healthy(struct vslpdir *vslpd)
  * >=1 : choose backend number n_retry (1= first)
  * altsrv_p : use altsrv_p to use next backend
  * healthy  : consider only healthy backends
+ *
+ * - find best backend based on health state
+ * - then apply rampup / altsrv_p
  */
 VCL_BACKEND vslpdir_pick_be(struct vslpdir *vslpd,
 		const struct vrt_ctx *ctx, uint32_t hash,
@@ -402,12 +406,15 @@ VCL_BACKEND vslpdir_pick_be(struct vslpdir *vslpd,
 	unsigned picklist_sz = VBITMAP_SZ(vslpd->n_backend);
 	char picklist_spc[picklist_sz];
 
-	state.picklist = vbit_init(picklist_spc, picklist_sz);
-	AN(state.picklist);
 	CHECK_OBJ_NOTNULL(vslpd, VSLPDIR_MAGIC);
 	CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
 	AN(ctx->vsl);
 
+	state.vslpd = vslpd;
+	state.ctx = ctx;
+	state.picklist = vbit_init(picklist_spc, picklist_sz);
+	AN(state.picklist);
+
 	if(altsrv_p)
 		be_choice = (scalbn(random(), -31) > vslpd->altsrv_p);
 
@@ -423,9 +430,6 @@ VCL_BACKEND vslpdir_pick_be(struct vslpdir *vslpd,
 		n_retry--;
 	}
 
-	state.vslpd = vslpd;
-	state.ctx = ctx;
-
 	if(vslpd->hashcircle == NULL)
 		WRONG("Incomplete VSLP hashcircle");