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regressions/ck_sequence: Work-around LLVM bug.

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For some reason, load operations were being re-ordered with respect
to read begin operation (even with explicit compiler barriers).
ck_pring
Samy Al Bahra 12 years ago
parent 7657df25a8
commit a56cac3a38
1 changed files with 11 additions and 9 deletions
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20
regressions/ck_sequence/validate/ck_sequence.c
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@ -53,7 +53,7 @@ consumer(void *unused CK_CC_UNUSED)
{ {
struct example copy; struct example copy;
uint32_t version; uint32_t version;
unsigned int counter = 0; unsigned int retries = 0;
unsigned int i; unsigned int i;
unused = NULL; unused = NULL;
@ -72,22 +72,24 @@ consumer(void *unused CK_CC_UNUSED)
*/ */
do { do {
version = ck_sequence_read_begin(&seqlock); version = ck_sequence_read_begin(&seqlock);
copy = global; copy.a = ck_pr_load_uint(&global.a);
counter++; copy.b = ck_pr_load_uint(&global.b);
} while (ck_sequence_read_retry(&seqlock, version)); copy.c = ck_pr_load_uint(&global.c);
retries++;
} while (ck_sequence_read_retry(&seqlock, version) == true);
if (copy.b != copy.a + 1000) { if (copy.b != copy.a + 1000) {
fprintf(stderr, "ERROR: Failed regression: copy.b\n"); fprintf(stderr, "ERROR: Failed regression: copy.b (%u != %u + %u / %u)\n", copy.b, copy.a, 1000, copy.a + 1000);
exit(EXIT_FAILURE); exit(EXIT_FAILURE);
} }
if (copy.c != copy.a + copy.b) { if (copy.c != copy.a + copy.b) {
fprintf(stderr, "ERROR: Failed regression: copy.c\n"); fprintf(stderr, "ERROR: Failed regression: copy.c (%u != %u + %u / %u)\n", copy.c, copy.a, copy.b, copy.a + copy.b);
exit(EXIT_FAILURE); exit(EXIT_FAILURE);
} }
} }
fprintf(stderr, "%u retries.\n", counter - STEPS); fprintf(stderr, "%u retries.\n", retries - STEPS);
ck_pr_dec_uint(&barrier); ck_pr_dec_uint(&barrier);
return (NULL); return (NULL);
} }
@ -136,8 +138,8 @@ main(int argc, char *argv[])
*/ */
ck_sequence_write_begin(&seqlock); ck_sequence_write_begin(&seqlock);
global.a = counter++; global.a = counter++;
ck_pr_store_uint(&global.b, global.a + 1000); global.b = global.a + 1000;
ck_pr_store_uint(&global.c, global.b + global.a); global.c = global.b + global.a;
ck_sequence_write_end(&seqlock); ck_sequence_write_end(&seqlock);
if (counter == 1) if (counter == 1)

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