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[OpenMP] Fix re-locking hang found in issue 86684 (#88539)

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This was initially reported here (including stacktraces):
https://stackoverflow.com/questions/78183545/does-compiling-imagick-with-openmp-enabled-in-freebsd-13-2-cause-sched-yield

If `__kmp_register_library_startup()` detects that another instance of
the library is present, `__kmp_is_address_mapped()` is eventually
called. which uses `kmpc_alloc()` to allocate memory. This function
calls `__kmp_entry_thread()` to access the thread-local memory pool,
which is a bad idea during initialization. This macro internally calls
`__kmp_get_global_thread_id_reg()` which sets the bootstrap lock at the
beginning (before calling `__kmp_register_library_startup()`).

The fix is to use `KMP_INTERNAL_MALLOC()`/`KMP_INTERNAL_FREE()` instead
of `kmpc_malloc()`/`kmpc_free()`. `KMP_INTERNAL_MALLOC` and
`KMP_INTERNAL_FREE` do not use any bootstrap locks. They just translate
to `malloc()`/`free()` and are meant to be used during library
initialization before other library-specific allocators have been
initialized.

Fixes: #86684
This commit is contained in:
Jonathan Peyton 2024-04-12 15:13:59 -05:00 committed by GitHub
parent 41ff91e143
commit 5300a6731e
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GPG Key ID: B5690EEEBB952194
1 changed files with 6 additions and 6 deletions
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12
openmp/runtime/src/z_Linux_util.cpp
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@ -2141,10 +2141,10 @@ int __kmp_is_address_mapped(void *addr) {
// We pass from number of vm entry's semantic
// to size of whole entry map list.
lstsz = lstsz * 4 / 3;
buf = reinterpret_cast<char *>(kmpc_malloc(lstsz));
buf = reinterpret_cast<char *>(KMP_INTERNAL_MALLOC(lstsz));
rc = sysctl(mib, 4, buf, &lstsz, NULL, 0);
if (rc < 0) {
kmpc_free(buf);
KMP_INTERNAL_FREE(buf);
return 0;
}
@ -2168,7 +2168,7 @@ int __kmp_is_address_mapped(void *addr) {
}
lw += cursz;
}
kmpc_free(buf);
KMP_INTERNAL_FREE(buf);
#elif KMP_OS_DRAGONFLY
char err[_POSIX2_LINE_MAX];
kinfo_proc *proc;
@ -2234,12 +2234,12 @@ int __kmp_is_address_mapped(void *addr) {
return 0;
}
buf = kmpc_malloc(sz);
buf = KMP_INTERNAL_MALLOC(sz);
while (sz > 0 && (rd = pread(file, buf, sz, 0)) == sz) {
void *newbuf;
sz <<= 1;
newbuf = kmpc_realloc(buf, sz);
newbuf = KMP_INTERNAL_REALLOC(buf, sz);
buf = newbuf;
}
@ -2255,7 +2255,7 @@ int __kmp_is_address_mapped(void *addr) {
}
}
kmpc_free(map);
KMP_INTERNAL_FREE(map);
close(file);
KMP_INTERNAL_FREE(name);
#elif KMP_OS_DARWIN