mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-12 14:20:13 +00:00
29496b3103
The rtld-audit interfaces introduces a slowdown due to enabling
profiling instrumentation (as if LD_AUDIT implied LD_PROFILE).
However, instrumenting is only necessary if one of audit libraries
provides PLT callbacks (la_pltenter or la_pltexit symbols). Otherwise,
the slowdown can be avoided.
The following patch adjusts the logic that enables profiling to iterate
over all audit modules and check if any of those provides a PLT hook.
To keep la_symbind to work even without PLT callbacks, _dl_fixup now
calls the audit callback if the modules implements it.
Co-authored-by: Alexander Monakov <amonakov@ispras.ru>
Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
(cherry picked from commit 063f9ba220)
Resolved conflicts:
NEWS
elf/Makefile
39 lines
1.3 KiB
C
39 lines
1.3 KiB
C
/* Check if DT_AUDIT a module without la_plt{enter,exit} symbols does not incur
|
|
in profiling (BZ#15533).
|
|
Copyright (C) 2021 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#include <link.h>
|
|
#include <support/xdlfcn.h>
|
|
#include <support/check.h>
|
|
|
|
static int
|
|
do_test (void)
|
|
{
|
|
void *h = xdlopen ("tst-auditmod19a.so", RTLD_NOW);
|
|
|
|
struct link_map *lmap;
|
|
TEST_VERIFY_EXIT (dlinfo (h, RTLD_DI_LINKMAP, &lmap) == 0);
|
|
|
|
/* The internal array is only allocated if profiling is enabled. */
|
|
TEST_VERIFY (lmap->l_reloc_result == NULL);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#include <support/test-driver.c>
|