Unify extent_alloc_wrapper with the other wrappers.

Previously, it was really more like extents_alloc (it looks in an ecache for an
extent to reuse as its primary allocation pathway).  Make that pathway more
explciitly like extents_alloc, and rename extent_alloc_wrapper_hard accordingly.

include/jemalloc/internal/extent2.h

@@ -29,10 +29,14 @@ extern rtree_t extents_rtree;
 edata_t *extents_alloc(tsdn_t *tsdn, arena_t *arena, ehooks_t *ehooks,
     ecache_t *ecache, void *new_addr, size_t size, size_t pad, size_t alignment,
     bool slab, szind_t szind, bool *zero, bool *commit);
+edata_t *extents_alloc_grow(tsdn_t *tsdn, arena_t *arena, ehooks_t *ehooks,
+    ecache_t *ecache, void *new_addr, size_t size, size_t pad, size_t alignment,
+    bool slab, szind_t szind, bool *zero, bool *commit);
 void extents_dalloc(tsdn_t *tsdn, arena_t *arena, ehooks_t *ehooks,
     ecache_t *ecache, edata_t *edata);
 edata_t *extents_evict(tsdn_t *tsdn, arena_t *arena, ehooks_t *ehooks,
     ecache_t *ecache, size_t npages_min);
+
 edata_t *extent_alloc_wrapper(tsdn_t *tsdn, arena_t *arena, ehooks_t *ehooks,
     void *new_addr, size_t size, size_t pad, size_t alignment, bool slab,
     szind_t szind, bool *zero, bool *commit);

src/arena.c

@@ -444,8 +444,9 @@ arena_extent_alloc_large(tsdn_t *tsdn, arena_t *arena, size_t usize,
 	}
 	size_t size = usize + sz_large_pad;
 	if (edata == NULL) {
-		edata = extent_alloc_wrapper(tsdn, arena, ehooks, NULL, usize,
+		edata = extents_alloc_grow(tsdn, arena, ehooks,
-		    sz_large_pad, alignment, false, szind, zero, &commit);
+		    &arena->ecache_retained, NULL, usize, sz_large_pad,
+		    alignment, false, szind, zero, &commit);
 		if (config_stats) {
 			/*
 			 * edata may be NULL on OOM, but in that case mapped_add
@@ -1210,8 +1211,8 @@ arena_slab_alloc_hard(tsdn_t *tsdn, arena_t *arena, ehooks_t *ehooks,
 
 	zero = false;
 	commit = true;
-	slab = extent_alloc_wrapper(tsdn, arena, ehooks, NULL,
+	slab = extents_alloc_grow(tsdn, arena, ehooks, &arena->ecache_retained,
-	    bin_info->slab_size, 0, PAGE, true, szind, &zero, &commit);
+	    NULL, bin_info->slab_size, 0, PAGE, true, szind, &zero, &commit);
 
 	if (config_stats && slab != NULL) {
 		arena_stats_mapped_add(tsdn, &arena->stats,

src/extent2.c

@@ -52,6 +52,9 @@ static edata_t *extent_try_coalesce(tsdn_t *tsdn, arena_t *arena,
     bool *coalesced, bool growing_retained);
 static void extent_record(tsdn_t *tsdn, arena_t *arena, ehooks_t *ehooks,
     ecache_t *ecache, edata_t *edata, bool growing_retained);
+static edata_t *extent_alloc_retained(tsdn_t *tsdn, arena_t *arena,
+    ehooks_t *ehooks, void *new_addr, size_t size, size_t pad, size_t alignment,
+    bool slab, szind_t szind, bool *zero, bool *commit);
 
 /******************************************************************************/
 
@@ -194,6 +197,35 @@ extents_alloc(tsdn_t *tsdn, arena_t *arena, ehooks_t *ehooks, ecache_t *ecache,
 	return edata;
 }
 
+edata_t *
+extents_alloc_grow(tsdn_t *tsdn, arena_t *arena, ehooks_t *ehooks,
+    ecache_t *ecache, void *new_addr, size_t size, size_t pad, size_t alignment,
+    bool slab, szind_t szind, bool *zero, bool *commit) {
+	assert(size + pad != 0);
+	assert(alignment != 0);
+	witness_assert_depth_to_rank(tsdn_witness_tsdp_get(tsdn),
+	    WITNESS_RANK_CORE, 0);
+
+	edata_t *edata = extent_alloc_retained(tsdn, arena, ehooks, new_addr,
+	    size, pad, alignment, slab, szind, zero, commit);
+	if (edata == NULL) {
+		if (opt_retain && new_addr != NULL) {
+			/*
+			 * When retain is enabled and new_addr is set, we do not
+			 * attempt extent_alloc_wrapper which does mmap that is
+			 * very unlikely to succeed (unless it happens to be at
+			 * the end).
+			 */
+			return NULL;
+		}
+		edata = extent_alloc_wrapper(tsdn, arena, ehooks,
+		    new_addr, size, pad, alignment, slab, szind, zero, commit);
+	}
+
+	assert(edata == NULL || edata_dumpable_get(edata));
+	return edata;
+}
+
 void
 extents_dalloc(tsdn_t *tsdn, arena_t *arena, ehooks_t *ehooks, ecache_t *ecache,
     edata_t *edata) {
@@ -996,10 +1028,13 @@ extent_alloc_retained(tsdn_t *tsdn, arena_t *arena, ehooks_t *ehooks,
 	return edata;
 }
 
-static edata_t *
+edata_t *
-extent_alloc_wrapper_hard(tsdn_t *tsdn, arena_t *arena, ehooks_t *ehooks,
+extent_alloc_wrapper(tsdn_t *tsdn, arena_t *arena, ehooks_t *ehooks,
     void *new_addr, size_t size, size_t pad, size_t alignment, bool slab,
     szind_t szind, bool *zero, bool *commit) {
+	witness_assert_depth_to_rank(tsdn_witness_tsdp_get(tsdn),
+	    WITNESS_RANK_CORE, 0);
+
 	size_t esize = size + pad;
 	edata_t *edata = edata_cache_get(tsdn, &arena->edata_cache,
 	    arena->base);
@@ -1027,33 +1062,6 @@ extent_alloc_wrapper_hard(tsdn_t *tsdn, arena_t *arena, ehooks_t *ehooks,
 	return edata;
 }
 
-edata_t *
-extent_alloc_wrapper(tsdn_t *tsdn, arena_t *arena, ehooks_t *ehooks,
-    void *new_addr, size_t size, size_t pad, size_t alignment, bool slab,
-    szind_t szind, bool *zero, bool *commit) {
-	witness_assert_depth_to_rank(tsdn_witness_tsdp_get(tsdn),
-	    WITNESS_RANK_CORE, 0);
-
-	edata_t *edata = extent_alloc_retained(tsdn, arena, ehooks, new_addr,
-	    size, pad, alignment, slab, szind, zero, commit);
-	if (edata == NULL) {
-		if (opt_retain && new_addr != NULL) {
-			/*
-			 * When retain is enabled and new_addr is set, we do not
-			 * attempt extent_alloc_wrapper_hard which does mmap
-			 * that is very unlikely to succeed (unless it happens
-			 * to be at the end).
-			 */
-			return NULL;
-		}
-		edata = extent_alloc_wrapper_hard(tsdn, arena, ehooks,
-		    new_addr, size, pad, alignment, slab, szind, zero, commit);
-	}
-
-	assert(edata == NULL || edata_dumpable_get(edata));
-	return edata;
-}
-
 static bool
 extent_can_coalesce(arena_t *arena, ecache_t *ecache, const edata_t *inner,
     const edata_t *outer) {

src/large.c

@@ -159,9 +159,10 @@ large_ralloc_no_move_expand(tsdn_t *tsdn, edata_t *edata, size_t usize,
 			new_mapping = false;
 		}
 	} else {
-		if ((trail = extent_alloc_wrapper(tsdn, arena, ehooks,
+		if ((trail = extents_alloc_grow(tsdn, arena, ehooks,
-		    edata_past_get(edata), trailsize, 0, CACHELINE, false,
+		    &arena->ecache_retained, edata_past_get(edata), trailsize,
-		    SC_NSIZES, &is_zeroed_trail, &commit)) == NULL) {
+		    0, CACHELINE, false, SC_NSIZES, &is_zeroed_trail, &commit))
+			== NULL) {
 			return true;
 		}
 		if (config_stats) {