1 /* SPDX-License-Identifier: LGPL-2.1 OR MIT */
2 /*
3 * Author: Paul Burton <paul.burton@mips.com>
4 * (C) Copyright 2018 MIPS Tech LLC
5 *
6 * Based on rseq-arm.h:
7 * (C) Copyright 2016-2018 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
8 */
9
10 /*
11 * RSEQ_SIG uses the break instruction. The instruction pattern is:
12 *
13 * On MIPS:
14 * 0350000d break 0x350
15 *
16 * On nanoMIPS:
17 * 00100350 break 0x350
18 *
19 * On microMIPS:
20 * 0000d407 break 0x350
21 *
22 * For nanoMIPS32 and microMIPS, the instruction stream is encoded as 16-bit
23 * halfwords, so the signature halfwords need to be swapped accordingly for
24 * little-endian.
25 */
26 #if defined(__nanomips__)
27 # ifdef __MIPSEL__
28 # define RSEQ_SIG 0x03500010
29 # else
30 # define RSEQ_SIG 0x00100350
31 # endif
32 #elif defined(__mips_micromips)
33 # ifdef __MIPSEL__
34 # define RSEQ_SIG 0xd4070000
35 # else
36 # define RSEQ_SIG 0x0000d407
37 # endif
38 #elif defined(__mips__)
39 # define RSEQ_SIG 0x0350000d
40 #else
41 /* Unknown MIPS architecture. */
42 #endif
43
44 #define rseq_smp_mb() __asm__ __volatile__ ("sync" ::: "memory")
45 #define rseq_smp_rmb() rseq_smp_mb()
46 #define rseq_smp_wmb() rseq_smp_mb()
47
48 #define rseq_smp_load_acquire(p) \
49 __extension__ ({ \
50 __typeof(*p) ____p1 = RSEQ_READ_ONCE(*p); \
51 rseq_smp_mb(); \
52 ____p1; \
53 })
54
55 #define rseq_smp_acquire__after_ctrl_dep() rseq_smp_rmb()
56
57 #define rseq_smp_store_release(p, v) \
58 do { \
59 rseq_smp_mb(); \
60 RSEQ_WRITE_ONCE(*p, v); \
61 } while (0)
62
63 #ifdef RSEQ_SKIP_FASTPATH
64 #include "rseq-skip.h"
65 #else /* !RSEQ_SKIP_FASTPATH */
66
67 #if _MIPS_SZLONG == 64
68 # define LONG ".dword"
69 # define LONG_LA "dla"
70 # define LONG_L "ld"
71 # define LONG_S "sd"
72 # define LONG_ADDI "daddiu"
73 # define U32_U64_PAD(x) x
74 #elif _MIPS_SZLONG == 32
75 # define LONG ".word"
76 # define LONG_LA "la"
77 # define LONG_L "lw"
78 # define LONG_S "sw"
79 # define LONG_ADDI "addiu"
80 # ifdef __BIG_ENDIAN
81 # define U32_U64_PAD(x) "0x0, " x
82 # else
83 # define U32_U64_PAD(x) x ", 0x0"
84 # endif
85 #else
86 # error unsupported _MIPS_SZLONG
87 #endif
88
89 #define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, start_ip, \
90 post_commit_offset, abort_ip) \
91 ".pushsection __rseq_cs, \"aw\"\n\t" \
92 ".balign 32\n\t" \
93 __rseq_str(label) ":\n\t" \
94 ".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \
95 LONG " " U32_U64_PAD(__rseq_str(start_ip)) "\n\t" \
96 LONG " " U32_U64_PAD(__rseq_str(post_commit_offset)) "\n\t" \
97 LONG " " U32_U64_PAD(__rseq_str(abort_ip)) "\n\t" \
98 ".popsection\n\t" \
99 ".pushsection __rseq_cs_ptr_array, \"aw\"\n\t" \
100 LONG " " U32_U64_PAD(__rseq_str(label) "b") "\n\t" \
101 ".popsection\n\t"
102
103 #define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \
104 __RSEQ_ASM_DEFINE_TABLE(label, 0x0, 0x0, start_ip, \
105 (post_commit_ip - start_ip), abort_ip)
106
107 /*
108 * Exit points of a rseq critical section consist of all instructions outside
109 * of the critical section where a critical section can either branch to or
110 * reach through the normal course of its execution. The abort IP and the
111 * post-commit IP are already part of the __rseq_cs section and should not be
112 * explicitly defined as additional exit points. Knowing all exit points is
113 * useful to assist debuggers stepping over the critical section.
114 */
115 #define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip) \
116 ".pushsection __rseq_exit_point_array, \"aw\"\n\t" \
117 LONG " " U32_U64_PAD(__rseq_str(start_ip)) "\n\t" \
118 LONG " " U32_U64_PAD(__rseq_str(exit_ip)) "\n\t" \
119 ".popsection\n\t"
120
121 #define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \
122 RSEQ_INJECT_ASM(1) \
123 LONG_LA " $4, " __rseq_str(cs_label) "\n\t" \
124 LONG_S " $4, %[" __rseq_str(rseq_cs) "]\n\t" \
125 __rseq_str(label) ":\n\t"
126
127 #define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label) \
128 RSEQ_INJECT_ASM(2) \
129 "lw $4, %[" __rseq_str(current_cpu_id) "]\n\t" \
130 "bne $4, %[" __rseq_str(cpu_id) "], " __rseq_str(label) "\n\t"
131
132 #define __RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, \
133 abort_label, version, flags, \
134 start_ip, post_commit_offset, abort_ip) \
135 ".balign 32\n\t" \
136 __rseq_str(table_label) ":\n\t" \
137 ".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \
138 LONG " " U32_U64_PAD(__rseq_str(start_ip)) "\n\t" \
139 LONG " " U32_U64_PAD(__rseq_str(post_commit_offset)) "\n\t" \
140 LONG " " U32_U64_PAD(__rseq_str(abort_ip)) "\n\t" \
141 ".word " __rseq_str(RSEQ_SIG) "\n\t" \
142 __rseq_str(label) ":\n\t" \
143 teardown \
144 "b %l[" __rseq_str(abort_label) "]\n\t"
145
146 #define RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, abort_label, \
147 start_ip, post_commit_ip, abort_ip) \
148 __RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, \
149 abort_label, 0x0, 0x0, start_ip, \
150 (post_commit_ip - start_ip), abort_ip)
151
152 #define RSEQ_ASM_DEFINE_CMPFAIL(label, teardown, cmpfail_label) \
153 __rseq_str(label) ":\n\t" \
154 teardown \
155 "b %l[" __rseq_str(cmpfail_label) "]\n\t"
156
157 static inline __attribute__((always_inline))
rseq_cmpeqv_storev(intptr_t * v,intptr_t expect,intptr_t newv,int cpu)158 int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu)
159 {
160 RSEQ_INJECT_C(9)
161
162 __asm__ __volatile__ goto (
163 RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */
164 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail])
165 #ifdef RSEQ_COMPARE_TWICE
166 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
167 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2])
168 #endif
169 /* Start rseq by storing table entry pointer into rseq_cs. */
170 RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
171 RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
172 RSEQ_INJECT_ASM(3)
173 LONG_L " $4, %[v]\n\t"
174 "bne $4, %[expect], %l[cmpfail]\n\t"
175 RSEQ_INJECT_ASM(4)
176 #ifdef RSEQ_COMPARE_TWICE
177 RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
178 LONG_L " $4, %[v]\n\t"
179 "bne $4, %[expect], %l[error2]\n\t"
180 #endif
181 /* final store */
182 LONG_S " %[newv], %[v]\n\t"
183 "2:\n\t"
184 RSEQ_INJECT_ASM(5)
185 "b 5f\n\t"
186 RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)
187 "5:\n\t"
188 : /* gcc asm goto does not allow outputs */
189 : [cpu_id] "r" (cpu),
190 [current_cpu_id] "m" (rseq_get_abi()->cpu_id),
191 [rseq_cs] "m" (rseq_get_abi()->rseq_cs.arch.ptr),
192 [v] "m" (*v),
193 [expect] "r" (expect),
194 [newv] "r" (newv)
195 RSEQ_INJECT_INPUT
196 : "$4", "memory"
197 RSEQ_INJECT_CLOBBER
198 : abort, cmpfail
199 #ifdef RSEQ_COMPARE_TWICE
200 , error1, error2
201 #endif
202 );
203 return 0;
204 abort:
205 RSEQ_INJECT_FAILED
206 return -1;
207 cmpfail:
208 return 1;
209 #ifdef RSEQ_COMPARE_TWICE
210 error1:
211 rseq_bug("cpu_id comparison failed");
212 error2:
213 rseq_bug("expected value comparison failed");
214 #endif
215 }
216
217 static inline __attribute__((always_inline))
rseq_cmpnev_storeoffp_load(intptr_t * v,intptr_t expectnot,long voffp,intptr_t * load,int cpu)218 int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot,
219 long voffp, intptr_t *load, int cpu)
220 {
221 RSEQ_INJECT_C(9)
222
223 __asm__ __volatile__ goto (
224 RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */
225 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail])
226 #ifdef RSEQ_COMPARE_TWICE
227 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
228 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2])
229 #endif
230 /* Start rseq by storing table entry pointer into rseq_cs. */
231 RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
232 RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
233 RSEQ_INJECT_ASM(3)
234 LONG_L " $4, %[v]\n\t"
235 "beq $4, %[expectnot], %l[cmpfail]\n\t"
236 RSEQ_INJECT_ASM(4)
237 #ifdef RSEQ_COMPARE_TWICE
238 RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
239 LONG_L " $4, %[v]\n\t"
240 "beq $4, %[expectnot], %l[error2]\n\t"
241 #endif
242 LONG_S " $4, %[load]\n\t"
243 LONG_ADDI " $4, %[voffp]\n\t"
244 LONG_L " $4, 0($4)\n\t"
245 /* final store */
246 LONG_S " $4, %[v]\n\t"
247 "2:\n\t"
248 RSEQ_INJECT_ASM(5)
249 "b 5f\n\t"
250 RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)
251 "5:\n\t"
252 : /* gcc asm goto does not allow outputs */
253 : [cpu_id] "r" (cpu),
254 [current_cpu_id] "m" (rseq_get_abi()->cpu_id),
255 [rseq_cs] "m" (rseq_get_abi()->rseq_cs.arch.ptr),
256 /* final store input */
257 [v] "m" (*v),
258 [expectnot] "r" (expectnot),
259 [voffp] "Ir" (voffp),
260 [load] "m" (*load)
261 RSEQ_INJECT_INPUT
262 : "$4", "memory"
263 RSEQ_INJECT_CLOBBER
264 : abort, cmpfail
265 #ifdef RSEQ_COMPARE_TWICE
266 , error1, error2
267 #endif
268 );
269 return 0;
270 abort:
271 RSEQ_INJECT_FAILED
272 return -1;
273 cmpfail:
274 return 1;
275 #ifdef RSEQ_COMPARE_TWICE
276 error1:
277 rseq_bug("cpu_id comparison failed");
278 error2:
279 rseq_bug("expected value comparison failed");
280 #endif
281 }
282
283 static inline __attribute__((always_inline))
rseq_addv(intptr_t * v,intptr_t count,int cpu)284 int rseq_addv(intptr_t *v, intptr_t count, int cpu)
285 {
286 RSEQ_INJECT_C(9)
287
288 __asm__ __volatile__ goto (
289 RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */
290 #ifdef RSEQ_COMPARE_TWICE
291 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
292 #endif
293 /* Start rseq by storing table entry pointer into rseq_cs. */
294 RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
295 RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
296 RSEQ_INJECT_ASM(3)
297 #ifdef RSEQ_COMPARE_TWICE
298 RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
299 #endif
300 LONG_L " $4, %[v]\n\t"
301 LONG_ADDI " $4, %[count]\n\t"
302 /* final store */
303 LONG_S " $4, %[v]\n\t"
304 "2:\n\t"
305 RSEQ_INJECT_ASM(4)
306 "b 5f\n\t"
307 RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)
308 "5:\n\t"
309 : /* gcc asm goto does not allow outputs */
310 : [cpu_id] "r" (cpu),
311 [current_cpu_id] "m" (rseq_get_abi()->cpu_id),
312 [rseq_cs] "m" (rseq_get_abi()->rseq_cs.arch.ptr),
313 [v] "m" (*v),
314 [count] "Ir" (count)
315 RSEQ_INJECT_INPUT
316 : "$4", "memory"
317 RSEQ_INJECT_CLOBBER
318 : abort
319 #ifdef RSEQ_COMPARE_TWICE
320 , error1
321 #endif
322 );
323 return 0;
324 abort:
325 RSEQ_INJECT_FAILED
326 return -1;
327 #ifdef RSEQ_COMPARE_TWICE
328 error1:
329 rseq_bug("cpu_id comparison failed");
330 #endif
331 }
332
333 static inline __attribute__((always_inline))
rseq_cmpeqv_trystorev_storev(intptr_t * v,intptr_t expect,intptr_t * v2,intptr_t newv2,intptr_t newv,int cpu)334 int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect,
335 intptr_t *v2, intptr_t newv2,
336 intptr_t newv, int cpu)
337 {
338 RSEQ_INJECT_C(9)
339
340 __asm__ __volatile__ goto (
341 RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */
342 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail])
343 #ifdef RSEQ_COMPARE_TWICE
344 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
345 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2])
346 #endif
347 /* Start rseq by storing table entry pointer into rseq_cs. */
348 RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
349 RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
350 RSEQ_INJECT_ASM(3)
351 LONG_L " $4, %[v]\n\t"
352 "bne $4, %[expect], %l[cmpfail]\n\t"
353 RSEQ_INJECT_ASM(4)
354 #ifdef RSEQ_COMPARE_TWICE
355 RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
356 LONG_L " $4, %[v]\n\t"
357 "bne $4, %[expect], %l[error2]\n\t"
358 #endif
359 /* try store */
360 LONG_S " %[newv2], %[v2]\n\t"
361 RSEQ_INJECT_ASM(5)
362 /* final store */
363 LONG_S " %[newv], %[v]\n\t"
364 "2:\n\t"
365 RSEQ_INJECT_ASM(6)
366 "b 5f\n\t"
367 RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)
368 "5:\n\t"
369 : /* gcc asm goto does not allow outputs */
370 : [cpu_id] "r" (cpu),
371 [current_cpu_id] "m" (rseq_get_abi()->cpu_id),
372 [rseq_cs] "m" (rseq_get_abi()->rseq_cs.arch.ptr),
373 /* try store input */
374 [v2] "m" (*v2),
375 [newv2] "r" (newv2),
376 /* final store input */
377 [v] "m" (*v),
378 [expect] "r" (expect),
379 [newv] "r" (newv)
380 RSEQ_INJECT_INPUT
381 : "$4", "memory"
382 RSEQ_INJECT_CLOBBER
383 : abort, cmpfail
384 #ifdef RSEQ_COMPARE_TWICE
385 , error1, error2
386 #endif
387 );
388 return 0;
389 abort:
390 RSEQ_INJECT_FAILED
391 return -1;
392 cmpfail:
393 return 1;
394 #ifdef RSEQ_COMPARE_TWICE
395 error1:
396 rseq_bug("cpu_id comparison failed");
397 error2:
398 rseq_bug("expected value comparison failed");
399 #endif
400 }
401
402 static inline __attribute__((always_inline))
rseq_cmpeqv_trystorev_storev_release(intptr_t * v,intptr_t expect,intptr_t * v2,intptr_t newv2,intptr_t newv,int cpu)403 int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect,
404 intptr_t *v2, intptr_t newv2,
405 intptr_t newv, int cpu)
406 {
407 RSEQ_INJECT_C(9)
408
409 __asm__ __volatile__ goto (
410 RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */
411 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail])
412 #ifdef RSEQ_COMPARE_TWICE
413 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
414 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2])
415 #endif
416 /* Start rseq by storing table entry pointer into rseq_cs. */
417 RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
418 RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
419 RSEQ_INJECT_ASM(3)
420 LONG_L " $4, %[v]\n\t"
421 "bne $4, %[expect], %l[cmpfail]\n\t"
422 RSEQ_INJECT_ASM(4)
423 #ifdef RSEQ_COMPARE_TWICE
424 RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
425 LONG_L " $4, %[v]\n\t"
426 "bne $4, %[expect], %l[error2]\n\t"
427 #endif
428 /* try store */
429 LONG_S " %[newv2], %[v2]\n\t"
430 RSEQ_INJECT_ASM(5)
431 "sync\n\t" /* full sync provides store-release */
432 /* final store */
433 LONG_S " %[newv], %[v]\n\t"
434 "2:\n\t"
435 RSEQ_INJECT_ASM(6)
436 "b 5f\n\t"
437 RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)
438 "5:\n\t"
439 : /* gcc asm goto does not allow outputs */
440 : [cpu_id] "r" (cpu),
441 [current_cpu_id] "m" (rseq_get_abi()->cpu_id),
442 [rseq_cs] "m" (rseq_get_abi()->rseq_cs.arch.ptr),
443 /* try store input */
444 [v2] "m" (*v2),
445 [newv2] "r" (newv2),
446 /* final store input */
447 [v] "m" (*v),
448 [expect] "r" (expect),
449 [newv] "r" (newv)
450 RSEQ_INJECT_INPUT
451 : "$4", "memory"
452 RSEQ_INJECT_CLOBBER
453 : abort, cmpfail
454 #ifdef RSEQ_COMPARE_TWICE
455 , error1, error2
456 #endif
457 );
458 return 0;
459 abort:
460 RSEQ_INJECT_FAILED
461 return -1;
462 cmpfail:
463 return 1;
464 #ifdef RSEQ_COMPARE_TWICE
465 error1:
466 rseq_bug("cpu_id comparison failed");
467 error2:
468 rseq_bug("expected value comparison failed");
469 #endif
470 }
471
472 static inline __attribute__((always_inline))
rseq_cmpeqv_cmpeqv_storev(intptr_t * v,intptr_t expect,intptr_t * v2,intptr_t expect2,intptr_t newv,int cpu)473 int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect,
474 intptr_t *v2, intptr_t expect2,
475 intptr_t newv, int cpu)
476 {
477 RSEQ_INJECT_C(9)
478
479 __asm__ __volatile__ goto (
480 RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */
481 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail])
482 #ifdef RSEQ_COMPARE_TWICE
483 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
484 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2])
485 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error3])
486 #endif
487 /* Start rseq by storing table entry pointer into rseq_cs. */
488 RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
489 RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
490 RSEQ_INJECT_ASM(3)
491 LONG_L " $4, %[v]\n\t"
492 "bne $4, %[expect], %l[cmpfail]\n\t"
493 RSEQ_INJECT_ASM(4)
494 LONG_L " $4, %[v2]\n\t"
495 "bne $4, %[expect2], %l[cmpfail]\n\t"
496 RSEQ_INJECT_ASM(5)
497 #ifdef RSEQ_COMPARE_TWICE
498 RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
499 LONG_L " $4, %[v]\n\t"
500 "bne $4, %[expect], %l[error2]\n\t"
501 LONG_L " $4, %[v2]\n\t"
502 "bne $4, %[expect2], %l[error3]\n\t"
503 #endif
504 /* final store */
505 LONG_S " %[newv], %[v]\n\t"
506 "2:\n\t"
507 RSEQ_INJECT_ASM(6)
508 "b 5f\n\t"
509 RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)
510 "5:\n\t"
511 : /* gcc asm goto does not allow outputs */
512 : [cpu_id] "r" (cpu),
513 [current_cpu_id] "m" (rseq_get_abi()->cpu_id),
514 [rseq_cs] "m" (rseq_get_abi()->rseq_cs.arch.ptr),
515 /* cmp2 input */
516 [v2] "m" (*v2),
517 [expect2] "r" (expect2),
518 /* final store input */
519 [v] "m" (*v),
520 [expect] "r" (expect),
521 [newv] "r" (newv)
522 RSEQ_INJECT_INPUT
523 : "$4", "memory"
524 RSEQ_INJECT_CLOBBER
525 : abort, cmpfail
526 #ifdef RSEQ_COMPARE_TWICE
527 , error1, error2, error3
528 #endif
529 );
530 return 0;
531 abort:
532 RSEQ_INJECT_FAILED
533 return -1;
534 cmpfail:
535 return 1;
536 #ifdef RSEQ_COMPARE_TWICE
537 error1:
538 rseq_bug("cpu_id comparison failed");
539 error2:
540 rseq_bug("1st expected value comparison failed");
541 error3:
542 rseq_bug("2nd expected value comparison failed");
543 #endif
544 }
545
546 static inline __attribute__((always_inline))
rseq_cmpeqv_trymemcpy_storev(intptr_t * v,intptr_t expect,void * dst,void * src,size_t len,intptr_t newv,int cpu)547 int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect,
548 void *dst, void *src, size_t len,
549 intptr_t newv, int cpu)
550 {
551 uintptr_t rseq_scratch[3];
552
553 RSEQ_INJECT_C(9)
554
555 __asm__ __volatile__ goto (
556 RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */
557 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail])
558 #ifdef RSEQ_COMPARE_TWICE
559 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
560 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2])
561 #endif
562 LONG_S " %[src], %[rseq_scratch0]\n\t"
563 LONG_S " %[dst], %[rseq_scratch1]\n\t"
564 LONG_S " %[len], %[rseq_scratch2]\n\t"
565 /* Start rseq by storing table entry pointer into rseq_cs. */
566 RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
567 RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
568 RSEQ_INJECT_ASM(3)
569 LONG_L " $4, %[v]\n\t"
570 "bne $4, %[expect], 5f\n\t"
571 RSEQ_INJECT_ASM(4)
572 #ifdef RSEQ_COMPARE_TWICE
573 RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f)
574 LONG_L " $4, %[v]\n\t"
575 "bne $4, %[expect], 7f\n\t"
576 #endif
577 /* try memcpy */
578 "beqz %[len], 333f\n\t" \
579 "222:\n\t" \
580 "lb $4, 0(%[src])\n\t" \
581 "sb $4, 0(%[dst])\n\t" \
582 LONG_ADDI " %[src], 1\n\t" \
583 LONG_ADDI " %[dst], 1\n\t" \
584 LONG_ADDI " %[len], -1\n\t" \
585 "bnez %[len], 222b\n\t" \
586 "333:\n\t" \
587 RSEQ_INJECT_ASM(5)
588 /* final store */
589 LONG_S " %[newv], %[v]\n\t"
590 "2:\n\t"
591 RSEQ_INJECT_ASM(6)
592 /* teardown */
593 LONG_L " %[len], %[rseq_scratch2]\n\t"
594 LONG_L " %[dst], %[rseq_scratch1]\n\t"
595 LONG_L " %[src], %[rseq_scratch0]\n\t"
596 "b 8f\n\t"
597 RSEQ_ASM_DEFINE_ABORT(3, 4,
598 /* teardown */
599 LONG_L " %[len], %[rseq_scratch2]\n\t"
600 LONG_L " %[dst], %[rseq_scratch1]\n\t"
601 LONG_L " %[src], %[rseq_scratch0]\n\t",
602 abort, 1b, 2b, 4f)
603 RSEQ_ASM_DEFINE_CMPFAIL(5,
604 /* teardown */
605 LONG_L " %[len], %[rseq_scratch2]\n\t"
606 LONG_L " %[dst], %[rseq_scratch1]\n\t"
607 LONG_L " %[src], %[rseq_scratch0]\n\t",
608 cmpfail)
609 #ifdef RSEQ_COMPARE_TWICE
610 RSEQ_ASM_DEFINE_CMPFAIL(6,
611 /* teardown */
612 LONG_L " %[len], %[rseq_scratch2]\n\t"
613 LONG_L " %[dst], %[rseq_scratch1]\n\t"
614 LONG_L " %[src], %[rseq_scratch0]\n\t",
615 error1)
616 RSEQ_ASM_DEFINE_CMPFAIL(7,
617 /* teardown */
618 LONG_L " %[len], %[rseq_scratch2]\n\t"
619 LONG_L " %[dst], %[rseq_scratch1]\n\t"
620 LONG_L " %[src], %[rseq_scratch0]\n\t",
621 error2)
622 #endif
623 "8:\n\t"
624 : /* gcc asm goto does not allow outputs */
625 : [cpu_id] "r" (cpu),
626 [current_cpu_id] "m" (rseq_get_abi()->cpu_id),
627 [rseq_cs] "m" (rseq_get_abi()->rseq_cs.arch.ptr),
628 /* final store input */
629 [v] "m" (*v),
630 [expect] "r" (expect),
631 [newv] "r" (newv),
632 /* try memcpy input */
633 [dst] "r" (dst),
634 [src] "r" (src),
635 [len] "r" (len),
636 [rseq_scratch0] "m" (rseq_scratch[0]),
637 [rseq_scratch1] "m" (rseq_scratch[1]),
638 [rseq_scratch2] "m" (rseq_scratch[2])
639 RSEQ_INJECT_INPUT
640 : "$4", "memory"
641 RSEQ_INJECT_CLOBBER
642 : abort, cmpfail
643 #ifdef RSEQ_COMPARE_TWICE
644 , error1, error2
645 #endif
646 );
647 return 0;
648 abort:
649 RSEQ_INJECT_FAILED
650 return -1;
651 cmpfail:
652 return 1;
653 #ifdef RSEQ_COMPARE_TWICE
654 error1:
655 rseq_bug("cpu_id comparison failed");
656 error2:
657 rseq_bug("expected value comparison failed");
658 #endif
659 }
660
661 static inline __attribute__((always_inline))
rseq_cmpeqv_trymemcpy_storev_release(intptr_t * v,intptr_t expect,void * dst,void * src,size_t len,intptr_t newv,int cpu)662 int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect,
663 void *dst, void *src, size_t len,
664 intptr_t newv, int cpu)
665 {
666 uintptr_t rseq_scratch[3];
667
668 RSEQ_INJECT_C(9)
669
670 __asm__ __volatile__ goto (
671 RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */
672 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail])
673 #ifdef RSEQ_COMPARE_TWICE
674 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
675 RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2])
676 #endif
677 LONG_S " %[src], %[rseq_scratch0]\n\t"
678 LONG_S " %[dst], %[rseq_scratch1]\n\t"
679 LONG_S " %[len], %[rseq_scratch2]\n\t"
680 /* Start rseq by storing table entry pointer into rseq_cs. */
681 RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
682 RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
683 RSEQ_INJECT_ASM(3)
684 LONG_L " $4, %[v]\n\t"
685 "bne $4, %[expect], 5f\n\t"
686 RSEQ_INJECT_ASM(4)
687 #ifdef RSEQ_COMPARE_TWICE
688 RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f)
689 LONG_L " $4, %[v]\n\t"
690 "bne $4, %[expect], 7f\n\t"
691 #endif
692 /* try memcpy */
693 "beqz %[len], 333f\n\t" \
694 "222:\n\t" \
695 "lb $4, 0(%[src])\n\t" \
696 "sb $4, 0(%[dst])\n\t" \
697 LONG_ADDI " %[src], 1\n\t" \
698 LONG_ADDI " %[dst], 1\n\t" \
699 LONG_ADDI " %[len], -1\n\t" \
700 "bnez %[len], 222b\n\t" \
701 "333:\n\t" \
702 RSEQ_INJECT_ASM(5)
703 "sync\n\t" /* full sync provides store-release */
704 /* final store */
705 LONG_S " %[newv], %[v]\n\t"
706 "2:\n\t"
707 RSEQ_INJECT_ASM(6)
708 /* teardown */
709 LONG_L " %[len], %[rseq_scratch2]\n\t"
710 LONG_L " %[dst], %[rseq_scratch1]\n\t"
711 LONG_L " %[src], %[rseq_scratch0]\n\t"
712 "b 8f\n\t"
713 RSEQ_ASM_DEFINE_ABORT(3, 4,
714 /* teardown */
715 LONG_L " %[len], %[rseq_scratch2]\n\t"
716 LONG_L " %[dst], %[rseq_scratch1]\n\t"
717 LONG_L " %[src], %[rseq_scratch0]\n\t",
718 abort, 1b, 2b, 4f)
719 RSEQ_ASM_DEFINE_CMPFAIL(5,
720 /* teardown */
721 LONG_L " %[len], %[rseq_scratch2]\n\t"
722 LONG_L " %[dst], %[rseq_scratch1]\n\t"
723 LONG_L " %[src], %[rseq_scratch0]\n\t",
724 cmpfail)
725 #ifdef RSEQ_COMPARE_TWICE
726 RSEQ_ASM_DEFINE_CMPFAIL(6,
727 /* teardown */
728 LONG_L " %[len], %[rseq_scratch2]\n\t"
729 LONG_L " %[dst], %[rseq_scratch1]\n\t"
730 LONG_L " %[src], %[rseq_scratch0]\n\t",
731 error1)
732 RSEQ_ASM_DEFINE_CMPFAIL(7,
733 /* teardown */
734 LONG_L " %[len], %[rseq_scratch2]\n\t"
735 LONG_L " %[dst], %[rseq_scratch1]\n\t"
736 LONG_L " %[src], %[rseq_scratch0]\n\t",
737 error2)
738 #endif
739 "8:\n\t"
740 : /* gcc asm goto does not allow outputs */
741 : [cpu_id] "r" (cpu),
742 [current_cpu_id] "m" (rseq_get_abi()->cpu_id),
743 [rseq_cs] "m" (rseq_get_abi()->rseq_cs.arch.ptr),
744 /* final store input */
745 [v] "m" (*v),
746 [expect] "r" (expect),
747 [newv] "r" (newv),
748 /* try memcpy input */
749 [dst] "r" (dst),
750 [src] "r" (src),
751 [len] "r" (len),
752 [rseq_scratch0] "m" (rseq_scratch[0]),
753 [rseq_scratch1] "m" (rseq_scratch[1]),
754 [rseq_scratch2] "m" (rseq_scratch[2])
755 RSEQ_INJECT_INPUT
756 : "$4", "memory"
757 RSEQ_INJECT_CLOBBER
758 : abort, cmpfail
759 #ifdef RSEQ_COMPARE_TWICE
760 , error1, error2
761 #endif
762 );
763 return 0;
764 abort:
765 RSEQ_INJECT_FAILED
766 return -1;
767 cmpfail:
768 return 1;
769 #ifdef RSEQ_COMPARE_TWICE
770 error1:
771 rseq_bug("cpu_id comparison failed");
772 error2:
773 rseq_bug("expected value comparison failed");
774 #endif
775 }
776
777 #endif /* !RSEQ_SKIP_FASTPATH */
778