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 Change: 193783
This commit is contained in:
Gareth Rees 2018-06-14 17:44:41 +01:00
parent fc5c7a9f86
commit e98b2a05c8
1 changed files with 17 additions and 10 deletions
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27
mps/code/forktest.c
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@ -1,11 +1,14 @@
/* tagtest.c: TAGGED POINTER TEST
/* forktest.c: FORK SAFETY TEST
*
* $Id: //info.ravenbrook.com/project/mps/branch/2018-06-13/fork/code/tagtest.c#1 $
* Copyright (c) 2018 Ravenbrook Limited. See end of file for license.
*
* .overview: This test case is a regression test for job004062. It
* checks that the MPS correctly runs in the child process after a
* fork() on FreeBSD, Linux or OS X.
* fork() on FreeBSD, Linux or macOS.
*
* .format: This test case uses a trivial object format in which each
* object contains a single reference.
*/
#include <stdio.h>
@ -26,9 +29,9 @@ enum {
typedef struct obj_s {
unsigned type; /* One of the TYPE_ enums */
union {
struct obj_s *ref;
mps_addr_t fwd;
size_t pad;
struct obj_s *ref; /* TYPE_REF */
mps_addr_t fwd; /* TYPE_FWD */
size_t pad; /* TYPE_PAD */
} u;
} obj_s, *obj_t;
@ -108,7 +111,8 @@ int main(int argc, char *argv[])
testlib_init(argc, argv);
/* Set the pause time to be very small so that the incremental
collector has to leave a read barrier in place for us to hit. */
collector (when it runs) will have to leave a read barrier in
place for us to hit. */
MPS_ARGS_BEGIN(args) {
MPS_ARGS_ADD(args, MPS_KEY_PAUSE_TIME, 0.0);
die(mps_arena_create_k(&arena, mps_arena_class_vm(), args),
@ -139,7 +143,7 @@ int main(int argc, char *argv[])
die(mps_ap_create_k(&obj_ap, pool, mps_args_none),
"Couldn't create obj allocation point");
/* Create a linked list of a million cells. */
/* Create a linked list of objects. */
first = NULL;
for (i = 0; i < 100000; ++i) {
size_t size = ALIGN_UP(sizeof(obj_s), ALIGNMENT);
@ -157,17 +161,20 @@ int main(int argc, char *argv[])
pid = fork();
cdie(pid >= 0, "fork failed");
if (pid == 0) {
/* Child: allow a collection to start */
/* Child: allow a collection to start, which will cause a read
barrier to be applied to any segment containing live objects
that was scanned. */
mps_arena_release(arena);
/* Read a bunch of stuff so that we hit the read barrier. */
/* Read all the objects, so that if there is read barrier in place
we will hit it. */
for (obj = first; obj != NULL; obj = obj->u.ref) {
Insist(obj->type == TYPE_REF);
}
mps_arena_park(arena);
} else {
/* Parent: wait for child result */
/* Parent: wait for child and check that its exit status is zero. */
int stat;
cdie(pid == waitpid(pid, &stat, 0), "waitpid failed");
cdie(WIFEXITED(stat), "child did not exit normally");