elf: Do not check for loader mmap on tst-decorate-maps (BZ 31553)

On some architectures and depending on the page size, the loader can
also allocate some memory during dependencies loading and it will be
marked as 'loader malloc'.  However, if the system page size is
large enough, the initial data page will be enough for all required
allocation and there will be no extra loader mmap.  To avoid false
negatives, the test does not check for such pages.

Checked on powerpc64le-linux-gnu with 64k pagesize.
Reviewed-by: Simon Chopin <simon.chopin@canonical.com>
This commit is contained in:
Adhemerval Zanella 2024-03-26 10:47:42 -03:00
parent f6d18bea38
commit 25b191f6d3

View File

@ -56,7 +56,6 @@ struct proc_maps_t
int n_user_threads; int n_user_threads;
int n_arenas; int n_arenas;
int n_malloc_mmap; int n_malloc_mmap;
int n_loader_malloc_mmap;
}; };
static struct proc_maps_t static struct proc_maps_t
@ -82,8 +81,12 @@ read_proc_maps (void)
r.n_arenas++; r.n_arenas++;
else if (strstr (line, "[anon: glibc: malloc]") != NULL) else if (strstr (line, "[anon: glibc: malloc]") != NULL)
r.n_malloc_mmap++; r.n_malloc_mmap++;
else if (strstr (line, "[anon: glibc: loader malloc]") != NULL) /* On some architectures and depending on the page size, the loader can
r.n_loader_malloc_mmap++; also allocate some memory during dependencies loading and it will be
marked as 'loader malloc'. However, if the system page size is large
enough, the initial data page will be enough for all required
allocation and there will be no extra loader mmap. To avoid false
negatives, the test does not check for such pages. */
} }
free (line); free (line);
xfclose (f); xfclose (f);
@ -148,8 +151,6 @@ do_test_threads (bool set_guard)
TEST_COMPARE (r.n_user_threads, num_user_threads); TEST_COMPARE (r.n_user_threads, num_user_threads);
TEST_COMPARE (r.n_arenas, expected_n_arenas); TEST_COMPARE (r.n_arenas, expected_n_arenas);
TEST_COMPARE (r.n_malloc_mmap, 1); TEST_COMPARE (r.n_malloc_mmap, 1);
/* On some architectures the loader might use more than one page. */
TEST_VERIFY (r.n_loader_malloc_mmap >= 1);
} }
/* Let the threads finish. */ /* Let the threads finish. */
@ -164,7 +165,6 @@ do_test_threads (bool set_guard)
TEST_COMPARE (r.n_user_threads, 0); TEST_COMPARE (r.n_user_threads, 0);
TEST_COMPARE (r.n_arenas, expected_n_arenas); TEST_COMPARE (r.n_arenas, expected_n_arenas);
TEST_COMPARE (r.n_malloc_mmap, 1); TEST_COMPARE (r.n_malloc_mmap, 1);
TEST_VERIFY (r.n_loader_malloc_mmap >= 1);
} }
free (p); free (p);