Consolidate arena_* header split into arena.h

arena_types.h + arena_structs.h + arena_externs.h merged into arena.h,
keeping the three logical sections (TYPES / STRUCTS / EXTERNS) with
explicit dividers.  arena_inlines_a.h and arena_inlines_b.h stay
separate; arena_inlines_b.h now carries a comment explaining why
merging the two would reintroduce a real #include cycle through
tcache_inlines.h -> arena_choose (the asymmetric cycle-breaker).

arena_decay_constants.h (new): minimal header for
ARENA_DECAY_NTICKS_PER_UPDATE.

include/jemalloc/internal/arena.h

@@ -1,14 +1,181 @@
-#ifndef JEMALLOC_INTERNAL_ARENA_EXTERNS_H
+#ifndef JEMALLOC_INTERNAL_ARENA_H
-#define JEMALLOC_INTERNAL_ARENA_EXTERNS_H
+#define JEMALLOC_INTERNAL_ARENA_H
 
 #include "jemalloc/internal/jemalloc_preamble.h"
+#include "jemalloc/internal/arena_decay_constants.h"
 #include "jemalloc/internal/arena_stats.h"
+#include "jemalloc/internal/atomic.h"
 #include "jemalloc/internal/bin.h"
+#include "jemalloc/internal/bitmap.h"
+#include "jemalloc/internal/counter.h"
 #include "jemalloc/internal/div.h"
+#include "jemalloc/internal/ecache.h"
+#include "jemalloc/internal/edata_cache.h"
 #include "jemalloc/internal/emap.h"
 #include "jemalloc/internal/extent_dss.h"
+#include "jemalloc/internal/jemalloc_internal_types.h"
+#include "jemalloc/internal/mutex.h"
+#include "jemalloc/internal/nstime.h"
+#include "jemalloc/internal/pa.h"
 #include "jemalloc/internal/pages.h"
+#include "jemalloc/internal/ql.h"
+#include "jemalloc/internal/sc.h"
 #include "jemalloc/internal/stats.h"
+#include "jemalloc/internal/ticker.h"
+
+/******************************************************************************/
+/* TYPES */
+/******************************************************************************/
+
+/* Default decay times in milliseconds. */
+#define DIRTY_DECAY_MS_DEFAULT ZD(10 * 1000)
+#define MUZZY_DECAY_MS_DEFAULT (0)
+/* Maximum length of the arena name. */
+#define ARENA_NAME_LEN 32
+
+typedef enum {
+	percpu_arena_mode_names_base = 0, /* Used for options processing. */
+
+	/*
+	 * *_uninit are used only during bootstrapping, and must correspond
+	 * to initialized variant plus percpu_arena_mode_enabled_base.
+	 */
+	percpu_arena_uninit = 0,
+	per_phycpu_arena_uninit = 1,
+
+	/* All non-disabled modes must come after percpu_arena_disabled. */
+	percpu_arena_disabled = 2,
+
+	percpu_arena_mode_names_limit = 3, /* Used for options processing. */
+	percpu_arena_mode_enabled_base = 3,
+
+	percpu_arena = 3,
+	per_phycpu_arena = 4 /* Hyper threads share arena. */
+} percpu_arena_mode_t;
+
+#define PERCPU_ARENA_ENABLED(m) ((m) >= percpu_arena_mode_enabled_base)
+#define PERCPU_ARENA_DEFAULT percpu_arena_disabled
+
+/*
+ * When allocation_size >= oversize_threshold, use the dedicated huge arena
+ * (unless have explicitly spicified arena index).  0 disables the feature.
+ */
+#define OVERSIZE_THRESHOLD_DEFAULT (8 << 20)
+
+struct arena_config_s {
+	/* extent hooks to be used for the arena */
+	extent_hooks_t *extent_hooks;
+
+	/*
+	 * Use extent hooks for metadata (base) allocations when true.
+	 */
+	bool metadata_use_hooks;
+};
+
+typedef struct arena_config_s arena_config_t;
+
+extern const arena_config_t arena_config_default;
+
+/******************************************************************************/
+/* STRUCTS */
+/******************************************************************************/
+
+struct arena_s {
+	/*
+	 * Number of threads currently assigned to this arena.  Each thread has
+	 * two distinct assignments, one for application-serving allocation, and
+	 * the other for internal metadata allocation.  Internal metadata must
+	 * not be allocated from arenas explicitly created via the arenas.create
+	 * mallctl, because the arena.<i>.reset mallctl indiscriminately
+	 * discards all allocations for the affected arena.
+	 *
+	 *   0: Application allocation.
+	 *   1: Internal metadata allocation.
+	 *
+	 * Synchronization: atomic.
+	 */
+	atomic_u_t nthreads[2];
+
+	/* Next bin shard for binding new threads. Synchronization: atomic. */
+	atomic_u_t binshard_next;
+
+	/*
+	 * When percpu_arena is enabled, to amortize the cost of reading /
+	 * updating the current CPU id, track the most recent thread accessing
+	 * this arena, and only read CPU if there is a mismatch.
+	 */
+	tsdn_t *last_thd;
+
+	/* Synchronization: internal. */
+	arena_stats_t stats;
+
+	/*
+	 * List of cache_bin_array_descriptors for extant threads associated
+	 * with this arena.  Stats from these are merged incrementally, and at
+	 * exit if opt_stats_print is enabled.
+	 *
+	 * Synchronization: cache_bin_array_descriptor_ql_mtx.
+	 */
+	ql_head(cache_bin_array_descriptor_t) cache_bin_array_descriptor_ql;
+	malloc_mutex_t cache_bin_array_descriptor_ql_mtx;
+
+	/*
+	 * Represents a dss_prec_t, but atomically.
+	 *
+	 * Synchronization: atomic.
+	 */
+	atomic_u_t dss_prec;
+
+	/*
+	 * Extant large allocations.
+	 *
+	 * Synchronization: large_mtx.
+	 */
+	edata_list_active_t large;
+	/* Synchronizes all large allocation/update/deallocation. */
+	malloc_mutex_t large_mtx;
+
+	/* The page-level allocator shard this arena uses. */
+	pa_shard_t pa_shard;
+
+	/*
+	 * A cached copy of base->ind.  This can get accessed on hot paths;
+	 * looking it up in base requires an extra pointer hop / cache miss.
+	 */
+	unsigned ind;
+
+	/*
+	 * Base allocator, from which arena metadata are allocated.
+	 *
+	 * Synchronization: internal.
+	 */
+	base_t *base;
+	/* Used to determine uptime.  Read-only after initialization. */
+	nstime_t create_time;
+
+	/* The name of the arena. */
+	char name[ARENA_NAME_LEN];
+
+	/*
+	 * The arena is allocated alongside its bins; really this is a
+	 * dynamically sized array determined by the binshard settings.
+	 * Enforcing cacheline-alignment to minimize the number of cachelines
+	 * touched on the hot paths.
+	 */
+	JEMALLOC_WARN_ON_USAGE(
+	    "Do not use this field directly. "
+	    "Use `arena_get_bin` instead.")
+	JEMALLOC_ALIGNED(CACHELINE)
+#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
+	bin_t all_bins[];
+#else
+	bin_t all_bins[0];
+#endif
+};
+
+/******************************************************************************/
+/* EXTERNS */
+/******************************************************************************/
 
 /*
  * When the amount of pages to be purged exceeds this amount, deferred purge
@@ -123,4 +290,4 @@ void   arena_postfork_parent(tsdn_t *tsdn, arena_t *arena);
 void   arena_postfork_child(tsdn_t *tsdn, arena_t *arena,
        cache_bin_array_descriptor_t *surviving_desc);
 
-#endif /* JEMALLOC_INTERNAL_ARENA_EXTERNS_H */
+#endif /* JEMALLOC_INTERNAL_ARENA_H */

include/jemalloc/internal/arena_decay_constants.h

@@ -0,0 +1,13 @@
+#ifndef JEMALLOC_INTERNAL_ARENA_DECAY_CONSTANTS_H
+#define JEMALLOC_INTERNAL_ARENA_DECAY_CONSTANTS_H
+
+/*
+ * Minimal header so both arena.h and tsd_internals.h can share decay-related
+ * constants without dragging the full arena types into the tsd parse chain
+ * (which is loaded long before arena.h via ckh.h -> tsd.h).
+ */
+
+/* Number of event ticks between time checks. */
+#define ARENA_DECAY_NTICKS_PER_UPDATE 1000
+
+#endif /* JEMALLOC_INTERNAL_ARENA_DECAY_CONSTANTS_H */

include/jemalloc/internal/arena_inlines_a.h

@@ -2,7 +2,7 @@
 #define JEMALLOC_INTERNAL_ARENA_INLINES_A_H
 
 #include "jemalloc/internal/jemalloc_preamble.h"
-#include "jemalloc/internal/arena_structs.h"
+#include "jemalloc/internal/arena.h"
 
 static inline unsigned
 arena_ind_get(const arena_t *arena) {

include/jemalloc/internal/arena_inlines_b.h

@@ -1,9 +1,27 @@
 #ifndef JEMALLOC_INTERNAL_ARENA_INLINES_B_H
 #define JEMALLOC_INTERNAL_ARENA_INLINES_B_H
 
+/*
+ * This split (arena_inlines_a.h + arena_inlines_b.h) is load-bearing, not
+ * stylistic.  arena_inlines_a.h holds the cheap field accessors that only
+ * depend on arena.h fields.  This file holds the larger inlines that depend
+ * on arena_choose(), prof, large, and friends.
+ *
+ * Merging the two would create a real #include cycle through arena_choose():
+ * jemalloc_internal_inlines_b.h defines arena_choose() and pulls in
+ * arena_inlines_a.h at the top for the cheap accessors.  arena_choose() is
+ * called from arena_choose_maybe_huge() in this file.  If that #include
+ * resolved to a merged "arena_inlines.h", arena_choose_maybe_huge() would
+ * be parsed before arena_choose() exists, and we would get an implicit
+ * declaration error -- arena_inlines.h cannot pull in
+ * jemalloc_internal_inlines_b.h to fix it (that file is mid-parse and its
+ * include guard is already set).
+ *
+ * Keep this file separate from arena_inlines_a.h.
+ */
+
 #include "jemalloc/internal/jemalloc_preamble.h"
-#include "jemalloc/internal/arena_externs.h"
+#include "jemalloc/internal/arena.h"
-#include "jemalloc/internal/arena_structs.h"
 #include "jemalloc/internal/bin_inlines.h"
 #include "jemalloc/internal/div.h"
 #include "jemalloc/internal/emap.h"

include/jemalloc/internal/arena_structs.h

@@ -1,114 +0,0 @@
-#ifndef JEMALLOC_INTERNAL_ARENA_STRUCTS_H
-#define JEMALLOC_INTERNAL_ARENA_STRUCTS_H
-
-#include "jemalloc/internal/jemalloc_preamble.h"
-#include "jemalloc/internal/arena_stats.h"
-#include "jemalloc/internal/atomic.h"
-#include "jemalloc/internal/bin.h"
-#include "jemalloc/internal/bitmap.h"
-#include "jemalloc/internal/counter.h"
-#include "jemalloc/internal/ecache.h"
-#include "jemalloc/internal/edata_cache.h"
-#include "jemalloc/internal/extent_dss.h"
-#include "jemalloc/internal/jemalloc_internal_types.h"
-#include "jemalloc/internal/mutex.h"
-#include "jemalloc/internal/nstime.h"
-#include "jemalloc/internal/pa.h"
-#include "jemalloc/internal/ql.h"
-#include "jemalloc/internal/sc.h"
-#include "jemalloc/internal/ticker.h"
-
-struct arena_s {
-	/*
-	 * Number of threads currently assigned to this arena.  Each thread has
-	 * two distinct assignments, one for application-serving allocation, and
-	 * the other for internal metadata allocation.  Internal metadata must
-	 * not be allocated from arenas explicitly created via the arenas.create
-	 * mallctl, because the arena.<i>.reset mallctl indiscriminately
-	 * discards all allocations for the affected arena.
-	 *
-	 *   0: Application allocation.
-	 *   1: Internal metadata allocation.
-	 *
-	 * Synchronization: atomic.
-	 */
-	atomic_u_t nthreads[2];
-
-	/* Next bin shard for binding new threads. Synchronization: atomic. */
-	atomic_u_t binshard_next;
-
-	/*
-	 * When percpu_arena is enabled, to amortize the cost of reading /
-	 * updating the current CPU id, track the most recent thread accessing
-	 * this arena, and only read CPU if there is a mismatch.
-	 */
-	tsdn_t *last_thd;
-
-	/* Synchronization: internal. */
-	arena_stats_t stats;
-
-	/*
-	 * List of cache_bin_array_descriptors for extant threads associated
-	 * with this arena.  Stats from these are merged incrementally, and at
-	 * exit if opt_stats_print is enabled.
-	 *
-	 * Synchronization: cache_bin_array_descriptor_ql_mtx.
-	 */
-	ql_head(cache_bin_array_descriptor_t) cache_bin_array_descriptor_ql;
-	malloc_mutex_t cache_bin_array_descriptor_ql_mtx;
-
-	/*
-	 * Represents a dss_prec_t, but atomically.
-	 *
-	 * Synchronization: atomic.
-	 */
-	atomic_u_t dss_prec;
-
-	/*
-	 * Extant large allocations.
-	 *
-	 * Synchronization: large_mtx.
-	 */
-	edata_list_active_t large;
-	/* Synchronizes all large allocation/update/deallocation. */
-	malloc_mutex_t large_mtx;
-
-	/* The page-level allocator shard this arena uses. */
-	pa_shard_t pa_shard;
-
-	/*
-	 * A cached copy of base->ind.  This can get accessed on hot paths;
-	 * looking it up in base requires an extra pointer hop / cache miss.
-	 */
-	unsigned ind;
-
-	/*
-	 * Base allocator, from which arena metadata are allocated.
-	 *
-	 * Synchronization: internal.
-	 */
-	base_t *base;
-	/* Used to determine uptime.  Read-only after initialization. */
-	nstime_t create_time;
-
-	/* The name of the arena. */
-	char name[ARENA_NAME_LEN];
-
-	/*
-	 * The arena is allocated alongside its bins; really this is a
-	 * dynamically sized array determined by the binshard settings.
-	 * Enforcing cacheline-alignment to minimize the number of cachelines
-	 * touched on the hot paths.
-	 */
-	JEMALLOC_WARN_ON_USAGE(
-	    "Do not use this field directly. "
-	    "Use `arena_get_bin` instead.")
-	JEMALLOC_ALIGNED(CACHELINE)
-#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
-	bin_t all_bins[];
-#else
-	bin_t all_bins[0];
-#endif
-};
-
-#endif /* JEMALLOC_INTERNAL_ARENA_STRUCTS_H */

include/jemalloc/internal/arena_types.h

@@ -1,60 +0,0 @@
-#ifndef JEMALLOC_INTERNAL_ARENA_TYPES_H
-#define JEMALLOC_INTERNAL_ARENA_TYPES_H
-
-#include "jemalloc/internal/jemalloc_preamble.h"
-#include "jemalloc/internal/sc.h"
-
-/* Default decay times in milliseconds. */
-#define DIRTY_DECAY_MS_DEFAULT ZD(10 * 1000)
-#define MUZZY_DECAY_MS_DEFAULT (0)
-/* Number of event ticks between time checks. */
-#define ARENA_DECAY_NTICKS_PER_UPDATE 1000
-/* Maximum length of the arena name. */
-#define ARENA_NAME_LEN 32
-
-typedef struct arena_s arena_t;
-
-typedef enum {
-	percpu_arena_mode_names_base = 0, /* Used for options processing. */
-
-	/*
-	 * *_uninit are used only during bootstrapping, and must correspond
-	 * to initialized variant plus percpu_arena_mode_enabled_base.
-	 */
-	percpu_arena_uninit = 0,
-	per_phycpu_arena_uninit = 1,
-
-	/* All non-disabled modes must come after percpu_arena_disabled. */
-	percpu_arena_disabled = 2,
-
-	percpu_arena_mode_names_limit = 3, /* Used for options processing. */
-	percpu_arena_mode_enabled_base = 3,
-
-	percpu_arena = 3,
-	per_phycpu_arena = 4 /* Hyper threads share arena. */
-} percpu_arena_mode_t;
-
-#define PERCPU_ARENA_ENABLED(m) ((m) >= percpu_arena_mode_enabled_base)
-#define PERCPU_ARENA_DEFAULT percpu_arena_disabled
-
-/*
- * When allocation_size >= oversize_threshold, use the dedicated huge arena
- * (unless have explicitly spicified arena index).  0 disables the feature.
- */
-#define OVERSIZE_THRESHOLD_DEFAULT (8 << 20)
-
-struct arena_config_s {
-	/* extent hooks to be used for the arena */
-	extent_hooks_t *extent_hooks;
-
-	/*
-	 * Use extent hooks for metadata (base) allocations when true.
-	 */
-	bool metadata_use_hooks;
-};
-
-typedef struct arena_config_s arena_config_t;
-
-extern const arena_config_t arena_config_default;
-
-#endif /* JEMALLOC_INTERNAL_ARENA_TYPES_H */

include/jemalloc/internal/arenas_management.h

@@ -1,7 +1,7 @@
 #ifndef JEMALLOC_INTERNAL_ARENAS_MANAGEMENT_H
 #define JEMALLOC_INTERNAL_ARENAS_MANAGEMENT_H
 
-#include "jemalloc/internal/arena_types.h"
+#include "jemalloc/internal/arena.h"
 #include "jemalloc/internal/atomic.h"
 #include "jemalloc/internal/tsd_types.h"
 

include/jemalloc/internal/extent_dss.h

@@ -2,9 +2,11 @@
 #define JEMALLOC_INTERNAL_EXTENT_DSS_H
 
 #include "jemalloc/internal/jemalloc_preamble.h"
-#include "jemalloc/internal/arena_types.h"
 #include "jemalloc/internal/tsd_types.h"
 
+/* Forward decl; arena.h includes us, so we can't include arena.h back. */
+typedef struct arena_s arena_t;
+
 typedef enum {
 	dss_prec_disabled = 0,
 	dss_prec_primary = 1,

include/jemalloc/internal/jemalloc_internal_externs.h

@@ -1,7 +1,6 @@
 #ifndef JEMALLOC_INTERNAL_EXTERNS_H
 #define JEMALLOC_INTERNAL_EXTERNS_H
 
-#include "jemalloc/internal/arena_types.h"
 #include "jemalloc/internal/atomic.h"
 #include "jemalloc/internal/fxp.h"
 #include "jemalloc/internal/hpa_opts.h"

include/jemalloc/internal/jemalloc_internal_includes.h

@@ -36,24 +36,13 @@
  * global jemalloc definitions, however.
  */
 
-/******************************************************************************/
+#include "jemalloc/internal/arena.h"
-/* TYPES */
-/******************************************************************************/
-
-#include "jemalloc/internal/arena_types.h"
-
-/******************************************************************************/
-/* STRUCTS */
-/******************************************************************************/
-
-#include "jemalloc/internal/arena_structs.h"
 
 /******************************************************************************/
 /* EXTERNS */
 /******************************************************************************/
 
 #include "jemalloc/internal/jemalloc_internal_externs.h"
-#include "jemalloc/internal/arena_externs.h"
 #include "jemalloc/internal/large.h"
 #include "jemalloc/internal/tcache.h"
 #include "jemalloc/internal/malloc_dispatch.h"

include/jemalloc/internal/jemalloc_internal_inlines_a.h

@@ -2,8 +2,7 @@
 #define JEMALLOC_INTERNAL_INLINES_A_H
 
 #include "jemalloc/internal/jemalloc_preamble.h"
-#include "jemalloc/internal/arena_externs.h"
+#include "jemalloc/internal/arena.h"
-#include "jemalloc/internal/arena_types.h"
 #include "jemalloc/internal/arenas_management.h"
 #include "jemalloc/internal/atomic.h"
 #include "jemalloc/internal/bit_util.h"

include/jemalloc/internal/jemalloc_internal_inlines_c.h

@@ -2,7 +2,7 @@
 #define JEMALLOC_INTERNAL_INLINES_C_H
 
 #include "jemalloc/internal/jemalloc_preamble.h"
-#include "jemalloc/internal/arena_externs.h"
+#include "jemalloc/internal/arena.h"
 #include "jemalloc/internal/arena_inlines_b.h"
 #include "jemalloc/internal/emap.h"
 #include "jemalloc/internal/jemalloc_init.h"

include/jemalloc/internal/large.h

@@ -4,7 +4,8 @@
 #include "jemalloc/internal/jemalloc_preamble.h"
 #include "jemalloc/internal/edata.h"
 
-/* Forward decl; only prof_info_t * is used as a pointer arg below. */
+/* Forward decls; only used as pointer types below. */
+typedef struct arena_s     arena_t;
 typedef struct prof_info_s prof_info_t;
 
 void *large_malloc(tsdn_t *tsdn, arena_t *arena, size_t usize, bool zero);

include/jemalloc/internal/malloc_dispatch_inlines.h

@@ -2,7 +2,7 @@
 #define JEMALLOC_INTERNAL_MALLOC_DISPATCH_INLINES_H
 
 #include "jemalloc/internal/jemalloc_preamble.h"
-#include "jemalloc/internal/arena_externs.h"
+#include "jemalloc/internal/arena.h"
 #include "jemalloc/internal/arena_inlines_b.h"
 #include "jemalloc/internal/bin_inlines.h"
 #include "jemalloc/internal/div.h"

include/jemalloc/internal/tcache.h

@@ -9,8 +9,9 @@
 #include "jemalloc/internal/thread_event_registry.h"
 #include "jemalloc/internal/ticker.h"
 
-/* Forward decl; only base_t * is used as a pointer arg below. */
+/* Forward decls; only used as pointer types below. */
-typedef struct base_s base_t;
+typedef struct arena_s arena_t;
+typedef struct base_s  base_t;
 
 /******************************************************************************/
 /* TYPES */

include/jemalloc/internal/tcache_inlines.h

@@ -2,7 +2,7 @@
 #define JEMALLOC_INTERNAL_TCACHE_INLINES_H
 
 #include "jemalloc/internal/jemalloc_preamble.h"
-#include "jemalloc/internal/arena_externs.h"
+#include "jemalloc/internal/arena.h"
 #include "jemalloc/internal/bin.h"
 #include "jemalloc/internal/jemalloc_internal_inlines_b.h"
 #include "jemalloc/internal/jemalloc_internal_types.h"

include/jemalloc/internal/tsd_internals.h

@@ -4,7 +4,7 @@
 #define JEMALLOC_INTERNAL_TSD_INTERNALS_H
 
 #include "jemalloc/internal/jemalloc_preamble.h"
-#include "jemalloc/internal/arena_types.h"
+#include "jemalloc/internal/arena_decay_constants.h"
 #include "jemalloc/internal/assert.h"
 #include "jemalloc/internal/tsd_binshards.h"
 #include "jemalloc/internal/jemalloc_internal_externs.h"
@@ -16,7 +16,13 @@
 #include "jemalloc/internal/util.h"
 #include "jemalloc/internal/witness.h"
 
-/* Forward decl; tsd_internals.h only uses prof_tdata_t as a pointer type. */
+/*
+ * Forward decls.  tsd_internals.h cannot include arena.h / prof.h directly:
+ * those headers' STRUCTS-section includes trigger mutex.h -> tsd.h ->
+ * tsd_generic.h, which would re-enter this file before its body finishes.
+ * Each consumer here only uses these as pointer types.
+ */
+typedef struct arena_s      arena_t;
 typedef struct prof_tdata_s prof_tdata_t;
 
 /*

test/integration/extent.c

@@ -2,7 +2,7 @@
 
 #include "test/extent_hooks.h"
 
-#include "jemalloc/internal/arena_types.h"
+#include "jemalloc/internal/arena.h"
 
 static void
 test_extent_body(unsigned arena_ind) {

test/unit/san_bump.c

@@ -1,7 +1,7 @@
 #include "test/jemalloc_test.h"
 #include "test/arena_util.h"
 
-#include "jemalloc/internal/arena_structs.h"
+#include "jemalloc/internal/arena.h"
 #include "jemalloc/internal/san_bump.h"
 
 static extent_hooks_t *san_bump_default_hooks;

test/unit/stats.c

@@ -1,6 +1,6 @@
 #include "test/jemalloc_test.h"
 
-#include "jemalloc/internal/arena_structs.h"
+#include "jemalloc/internal/arena.h"
 
 #define STRINGIFY_HELPER(x) #x
 #define STRINGIFY(x) STRINGIFY_HELPER(x)