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1 #ifndef JEMALLOC_INTERNAL_TSD_H
2 #define JEMALLOC_INTERNAL_TSD_H
3 
4 #include "jemalloc/internal/arena_types.h"
5 #include "jemalloc/internal/assert.h"
6 #include "jemalloc/internal/jemalloc_internal_externs.h"
7 #include "jemalloc/internal/prof_types.h"
8 #include "jemalloc/internal/ql.h"
9 #include "jemalloc/internal/rtree_tsd.h"
10 #include "jemalloc/internal/tcache_types.h"
11 #include "jemalloc/internal/tcache_structs.h"
12 #include "jemalloc/internal/util.h"
13 #include "jemalloc/internal/witness.h"
14 
15 /*
16  * Thread-Specific-Data layout
17  * --- data accessed on tcache fast path: state, rtree_ctx, stats, prof ---
18  * s: state
19  * e: tcache_enabled
20  * m: thread_allocated (config_stats)
21  * f: thread_deallocated (config_stats)
22  * p: prof_tdata (config_prof)
23  * c: rtree_ctx (rtree cache accessed on deallocation)
24  * t: tcache
25  * --- data not accessed on tcache fast path: arena-related fields ---
26  * d: arenas_tdata_bypass
27  * r: reentrancy_level
28  * x: narenas_tdata
29  * i: iarena
30  * a: arena
31  * o: arenas_tdata
32  * Loading TSD data is on the critical path of basically all malloc operations.
33  * In particular, tcache and rtree_ctx rely on hot CPU cache to be effective.
34  * Use a compact layout to reduce cache footprint.
35  * +--- 64-bit and 64B cacheline; 1B each letter; First byte on the left. ---+
36  * |----------------------------  1st cacheline  ----------------------------|
37  * | sedrxxxx mmmmmmmm ffffffff pppppppp [c * 32  ........ ........ .......] |
38  * |----------------------------  2nd cacheline  ----------------------------|
39  * | [c * 64  ........ ........ ........ ........ ........ ........ .......] |
40  * |----------------------------  3nd cacheline  ----------------------------|
41  * | [c * 32  ........ ........ .......] iiiiiiii aaaaaaaa oooooooo [t...... |
42  * +-------------------------------------------------------------------------+
43  * Note: the entire tcache is embedded into TSD and spans multiple cachelines.
44  *
45  * The last 3 members (i, a and o) before tcache isn't really needed on tcache
46  * fast path.  However we have a number of unused tcache bins and witnesses
47  * (never touched unless config_debug) at the end of tcache, so we place them
48  * there to avoid breaking the cachelines and possibly paging in an extra page.
49  */
50 #ifdef JEMALLOC_JET
51 typedef void (*test_callback_t)(int *);
52 #  define MALLOC_TSD_TEST_DATA_INIT 0x72b65c10
53 #  define MALLOC_TEST_TSD \
54     O(test_data,		int,			int)		\
55     O(test_callback,		test_callback_t,	int)
56 #  define MALLOC_TEST_TSD_INITIALIZER , MALLOC_TSD_TEST_DATA_INIT, NULL
57 #else
58 #  define MALLOC_TEST_TSD
59 #  define MALLOC_TEST_TSD_INITIALIZER
60 #endif
61 
62 /*  O(name,			type,			nullable type */
63 #define MALLOC_TSD							\
64     O(tcache_enabled,		bool,			bool)		\
65     O(arenas_tdata_bypass,	bool,			bool)		\
66     O(reentrancy_level,		int8_t,			int8_t)		\
67     O(narenas_tdata,		uint32_t,		uint32_t)	\
68     O(offset_state,		uint64_t,		uint64_t)	\
69     O(thread_allocated,		uint64_t,		uint64_t)	\
70     O(thread_deallocated,	uint64_t,		uint64_t)	\
71     O(prof_tdata,		prof_tdata_t *,		prof_tdata_t *)	\
72     O(rtree_ctx,		rtree_ctx_t,		rtree_ctx_t)	\
73     O(iarena,			arena_t *,		arena_t *)	\
74     O(arena,			arena_t *,		arena_t *)	\
75     O(arenas_tdata,		arena_tdata_t *,	arena_tdata_t *)\
76     O(tcache,			tcache_t,		tcache_t)	\
77     O(witness_tsd,              witness_tsd_t,		witness_tsdn_t)	\
78     MALLOC_TEST_TSD
79 
80 #define TSD_INITIALIZER {						\
81     tsd_state_uninitialized,						\
82     TCACHE_ENABLED_ZERO_INITIALIZER,					\
83     false,								\
84     0,									\
85     0,									\
86     0,									\
87     0,									\
88     0,									\
89     NULL,								\
90     RTREE_CTX_ZERO_INITIALIZER,						\
91     NULL,								\
92     NULL,								\
93     NULL,								\
94     TCACHE_ZERO_INITIALIZER,						\
95     WITNESS_TSD_INITIALIZER						\
96     MALLOC_TEST_TSD_INITIALIZER						\
97 }
98 
99 enum {
100 	tsd_state_nominal = 0, /* Common case --> jnz. */
101 	tsd_state_nominal_slow = 1, /* Initialized but on slow path. */
102 	/* the above 2 nominal states should be lower values. */
103 	tsd_state_nominal_max = 1, /* used for comparison only. */
104 	tsd_state_minimal_initialized = 2,
105 	tsd_state_purgatory = 3,
106 	tsd_state_reincarnated = 4,
107 	tsd_state_uninitialized = 5
108 };
109 
110 /* Manually limit tsd_state_t to a single byte. */
111 typedef uint8_t tsd_state_t;
112 
113 /* The actual tsd. */
114 struct tsd_s {
115 	/*
116 	 * The contents should be treated as totally opaque outside the tsd
117 	 * module.  Access any thread-local state through the getters and
118 	 * setters below.
119 	 */
120 	tsd_state_t	state;
121 #define O(n, t, nt)							\
122 	t use_a_getter_or_setter_instead_##n;
123 MALLOC_TSD
124 #undef O
125 };
126 
127 /*
128  * Wrapper around tsd_t that makes it possible to avoid implicit conversion
129  * between tsd_t and tsdn_t, where tsdn_t is "nullable" and has to be
130  * explicitly converted to tsd_t, which is non-nullable.
131  */
132 struct tsdn_s {
133 	tsd_t tsd;
134 };
135 #define TSDN_NULL ((tsdn_t *)0)
136 JEMALLOC_ALWAYS_INLINE tsdn_t *
tsd_tsdn(tsd_t * tsd)137 tsd_tsdn(tsd_t *tsd) {
138 	return (tsdn_t *)tsd;
139 }
140 
141 JEMALLOC_ALWAYS_INLINE bool
tsdn_null(const tsdn_t * tsdn)142 tsdn_null(const tsdn_t *tsdn) {
143 	return tsdn == NULL;
144 }
145 
146 JEMALLOC_ALWAYS_INLINE tsd_t *
tsdn_tsd(tsdn_t * tsdn)147 tsdn_tsd(tsdn_t *tsdn) {
148 	assert(!tsdn_null(tsdn));
149 
150 	return &tsdn->tsd;
151 }
152 
153 void *malloc_tsd_malloc(size_t size);
154 void malloc_tsd_dalloc(void *wrapper);
155 void malloc_tsd_cleanup_register(bool (*f)(void));
156 tsd_t *malloc_tsd_boot0(void);
157 void malloc_tsd_boot1(void);
158 void tsd_cleanup(void *arg);
159 tsd_t *tsd_fetch_slow(tsd_t *tsd, bool internal);
160 void tsd_slow_update(tsd_t *tsd);
161 
162 /*
163  * We put the platform-specific data declarations and inlines into their own
164  * header files to avoid cluttering this file.  They define tsd_boot0,
165  * tsd_boot1, tsd_boot, tsd_booted_get, tsd_get_allocates, tsd_get, and tsd_set.
166  */
167 #ifdef JEMALLOC_MALLOC_THREAD_CLEANUP
168 #include "jemalloc/internal/tsd_malloc_thread_cleanup.h"
169 #elif (defined(JEMALLOC_TLS))
170 #include "jemalloc/internal/tsd_tls.h"
171 #elif (defined(_WIN32))
172 #include "jemalloc/internal/tsd_win.h"
173 #else
174 #include "jemalloc/internal/tsd_generic.h"
175 #endif
176 
177 /*
178  * tsd_foop_get_unsafe(tsd) returns a pointer to the thread-local instance of
179  * foo.  This omits some safety checks, and so can be used during tsd
180  * initialization and cleanup.
181  */
182 #define O(n, t, nt)							\
183 JEMALLOC_ALWAYS_INLINE t *						\
184 tsd_##n##p_get_unsafe(tsd_t *tsd) {					\
185 	return &tsd->use_a_getter_or_setter_instead_##n;		\
186 }
187 MALLOC_TSD
188 #undef O
189 
190 /* tsd_foop_get(tsd) returns a pointer to the thread-local instance of foo. */
191 #define O(n, t, nt)							\
192 JEMALLOC_ALWAYS_INLINE t *						\
193 tsd_##n##p_get(tsd_t *tsd) {						\
194 	assert(tsd->state == tsd_state_nominal ||			\
195 	    tsd->state == tsd_state_nominal_slow ||			\
196 	    tsd->state == tsd_state_reincarnated ||			\
197 	    tsd->state == tsd_state_minimal_initialized);		\
198 	return tsd_##n##p_get_unsafe(tsd);				\
199 }
200 MALLOC_TSD
201 #undef O
202 
203 /*
204  * tsdn_foop_get(tsdn) returns either the thread-local instance of foo (if tsdn
205  * isn't NULL), or NULL (if tsdn is NULL), cast to the nullable pointer type.
206  */
207 #define O(n, t, nt)							\
208 JEMALLOC_ALWAYS_INLINE nt *						\
209 tsdn_##n##p_get(tsdn_t *tsdn) {						\
210 	if (tsdn_null(tsdn)) {						\
211 		return NULL;						\
212 	}								\
213 	tsd_t *tsd = tsdn_tsd(tsdn);					\
214 	return (nt *)tsd_##n##p_get(tsd);				\
215 }
216 MALLOC_TSD
217 #undef O
218 
219 /* tsd_foo_get(tsd) returns the value of the thread-local instance of foo. */
220 #define O(n, t, nt)							\
221 JEMALLOC_ALWAYS_INLINE t						\
222 tsd_##n##_get(tsd_t *tsd) {						\
223 	return *tsd_##n##p_get(tsd);					\
224 }
225 MALLOC_TSD
226 #undef O
227 
228 /* tsd_foo_set(tsd, val) updates the thread-local instance of foo to be val. */
229 #define O(n, t, nt)							\
230 JEMALLOC_ALWAYS_INLINE void						\
231 tsd_##n##_set(tsd_t *tsd, t val) {					\
232 	assert(tsd->state != tsd_state_reincarnated &&			\
233 	    tsd->state != tsd_state_minimal_initialized);		\
234 	*tsd_##n##p_get(tsd) = val;					\
235 }
236 MALLOC_TSD
237 #undef O
238 
239 JEMALLOC_ALWAYS_INLINE void
tsd_assert_fast(tsd_t * tsd)240 tsd_assert_fast(tsd_t *tsd) {
241 	assert(!malloc_slow && tsd_tcache_enabled_get(tsd) &&
242 	    tsd_reentrancy_level_get(tsd) == 0);
243 }
244 
245 JEMALLOC_ALWAYS_INLINE bool
tsd_fast(tsd_t * tsd)246 tsd_fast(tsd_t *tsd) {
247 	bool fast = (tsd->state == tsd_state_nominal);
248 	if (fast) {
249 		tsd_assert_fast(tsd);
250 	}
251 
252 	return fast;
253 }
254 
255 JEMALLOC_ALWAYS_INLINE tsd_t *
tsd_fetch_impl(bool init,bool minimal)256 tsd_fetch_impl(bool init, bool minimal) {
257 	tsd_t *tsd = tsd_get(init);
258 
259 	if (!init && tsd_get_allocates() && tsd == NULL) {
260 		return NULL;
261 	}
262 	assert(tsd != NULL);
263 
264 	if (unlikely(tsd->state != tsd_state_nominal)) {
265 		return tsd_fetch_slow(tsd, minimal);
266 	}
267 	assert(tsd_fast(tsd));
268 	tsd_assert_fast(tsd);
269 
270 	return tsd;
271 }
272 
273 /* Get a minimal TSD that requires no cleanup.  See comments in free(). */
274 JEMALLOC_ALWAYS_INLINE tsd_t *
tsd_fetch_min(void)275 tsd_fetch_min(void) {
276 	return tsd_fetch_impl(true, true);
277 }
278 
279 /* For internal background threads use only. */
280 JEMALLOC_ALWAYS_INLINE tsd_t *
tsd_internal_fetch(void)281 tsd_internal_fetch(void) {
282 	tsd_t *tsd = tsd_fetch_min();
283 	/* Use reincarnated state to prevent full initialization. */
284 	tsd->state = tsd_state_reincarnated;
285 
286 	return tsd;
287 }
288 
289 JEMALLOC_ALWAYS_INLINE tsd_t *
tsd_fetch(void)290 tsd_fetch(void) {
291 	return tsd_fetch_impl(true, false);
292 }
293 
294 static inline bool
tsd_nominal(tsd_t * tsd)295 tsd_nominal(tsd_t *tsd) {
296 	return (tsd->state <= tsd_state_nominal_max);
297 }
298 
299 JEMALLOC_ALWAYS_INLINE tsdn_t *
tsdn_fetch(void)300 tsdn_fetch(void) {
301 	if (!tsd_booted_get()) {
302 		return NULL;
303 	}
304 
305 	return tsd_tsdn(tsd_fetch_impl(false, false));
306 }
307 
308 JEMALLOC_ALWAYS_INLINE rtree_ctx_t *
tsd_rtree_ctx(tsd_t * tsd)309 tsd_rtree_ctx(tsd_t *tsd) {
310 	return tsd_rtree_ctxp_get(tsd);
311 }
312 
313 JEMALLOC_ALWAYS_INLINE rtree_ctx_t *
tsdn_rtree_ctx(tsdn_t * tsdn,rtree_ctx_t * fallback)314 tsdn_rtree_ctx(tsdn_t *tsdn, rtree_ctx_t *fallback) {
315 	/*
316 	 * If tsd cannot be accessed, initialize the fallback rtree_ctx and
317 	 * return a pointer to it.
318 	 */
319 	if (unlikely(tsdn_null(tsdn))) {
320 		rtree_ctx_data_init(fallback);
321 		return fallback;
322 	}
323 	return tsd_rtree_ctx(tsdn_tsd(tsdn));
324 }
325 
326 #endif /* JEMALLOC_INTERNAL_TSD_H */
327