I am using perf syscall to collect etm traces for btraces implementation in GDB running on Linux kernel 5.9.1 on a cortex A7. in this test case, I am debugging a multi-threaded process (2 pthreads). For each thread, GDB is calling the sys call perf_event_open and gives the corresponding thread ptid.lwp as argument. for each syscall, the AUX buffer is mmap(ped) to a dedicated memory. this is working for almost all test cases I have, except this one, where it has 50% failure rate when executed manually. 90% failure rate when executed from a script.

/* This testcase is part of GDB, the GNU debugger.

   Copyright 2013-2019 Free Software Foundation, Inc.

   Contributed by Intel Corp. <markus.t.metzger@intel.com>

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include <pthread.h>

static pthread_barrier_t barrier;
static int global;

static void *
test (void *arg)
{
  pthread_barrier_wait (&barrier);

  global = 42; /* bp.1 */

  pthread_barrier_wait (&barrier);

  global = 42; /* bp.2 */

  return arg;
}

int
main (void)
{
  pthread_t th;

  pthread_barrier_init (&barrier, NULL, 2);
  pthread_create (&th, NULL, test, NULL);

  test (NULL);

  pthread_join (th, NULL);
  pthread_barrier_destroy (&barrier);

  return 0; /* bp.3 */
}

in this test case, a breakpoint is set at the line containing the comment /* bp.1 */ , and we start collecting traces. a second breakpoint is set at the line containing the comment /* bp.2 */, and we analyze collected traces.

thread 1 [Switching to thread 1 (Thread 0xb6ff9ca0 (LWP 8813))] #0 test (arg=0x0) at /home/ubuntu/development/gdb/build/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.btrace/multi-thread-step.c:34 34 global = 42; /* bp.2 */ (gdb) info record Active record target: record-btrace Recording format: arm Processor CoreSight ETM Trace. Buffer size: 8kB. Recorded 126 instructions in 15 functions (0 gaps) for thread 1 (Thread 0xb6ff9ca0 (LWP 8813)). (gdb) record function-call-history /ilc 1 test inst 1,9 at /home/ubuntu/development/gdb/build/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.btrace/multi-thread-step.c:30,32 2 pthread_barrier_wait@plt inst 10,12 at 3 pthread_barrier_wait inst 13,32 at 4 __aeabi_uidivmod inst 33,36 at 5 __udivsi3 inst 37,39 at 6 __udivsi3 inst 40,48 at 7 __aeabi_uidivmod inst 49,52 at 8 pthread_barrier_wait inst 53,77 at 9 __libc_do_syscall inst 78,80 at 10 pthread_barrier_wait inst 81,102 at 11 __aeabi_uidivmod inst 103,106 at 12 __udivsi3 inst 107,109 at 13 __udivsi3 inst 110,118 at 14 __aeabi_uidivmod inst 119,122 at 15 pthread_barrier_wait inst 123,126 at

(gdb) thread 1 [Switching to thread 1 (Thread 0xb6ff9ca0 (LWP 8826))] #0 test (arg=0x0) at /home/ubuntu/development/gdb/build/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.btrace/multi-thread-step.c:34 34 global = 42; /* bp.2 */ (gdb) info record Active record target: record-btrace Recording format: arm Processor CoreSight ETM Trace. Buffer size: 8kB. Recorded 276 instructions in 36 functions (0 gaps) for thread 1 (Thread 0xb6ff9ca0 (LWP 8826)). (gdb) record function-call-history /ilc 1 1 test inst 1,9 at /home/ubuntu/development/gdb/build/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.btrace/multi-thread-step.c:30,32 2 pthread_barrier_wait@plt inst 10,12 at 3 pthread_barrier_wait inst 13,32 at 4 __aeabi_uidivmod inst 33,36 at 5 __udivsi3 inst 37,39 at 6 __udivsi3 inst 40,48 at 7 __aeabi_uidivmod inst 49,52 at 8 pthread_barrier_wait inst 53,77 at 9 __libc_do_syscall inst 78,80 at 10 test inst 81,88 at /home/ubuntu/development/gdb/build/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.btrace/multi-thread-step.c:30,32 11 pthread_barrier_wait@plt inst 89,91 at 12 pthread_barrier_wait inst 92,111 at 13 __aeabi_uidivmod inst 112,115 at 14 __udivsi3 inst 116,118 at 15 __udivsi3 inst 119,127 at 16 __aeabi_uidivmod inst 128,131 at 17 pthread_barrier_wait inst 132,145 at 18 __aeabi_uidivmod inst 146,149 at 19 __udivsi3 inst 150,152 at 20 __udivsi3 inst 153,161 at 21 __aeabi_uidivmod inst 162,165 at 22 pthread_barrier_wait inst 166,182 at 23 __libc_do_syscall inst 183,185 at 24 pthread_barrier_wait inst 186,205 at 25 __aeabi_uidivmod inst 206,209 at 26 __udivsi3 inst 210,212 at 27 __udivsi3 inst 213,221 at 28 __aeabi_uidivmod inst 222,225 at 29 pthread_barrier_wait inst 226,229 at 30 test inst 230,230 at /home/ubuntu/development/gdb/build/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.btrace/multi-thread-step.c:34 31 pthread_barrier_wait inst 231,252 at 32 __aeabi_uidivmod inst 253,256 at 33 __udivsi3 inst 257,259 at 34 __udivsi3 inst 260,268 at 35 __aeabi_uidivmod inst 269,272 at 36 pthread_barrier_wait inst 273,276 at

cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_NO_SYNC cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_TRACE_ON cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_PE_CONTEXT --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_EXCEPTION cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_NO_SYNC cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_TRACE_ON cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_PE_CONTEXT --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_EXCEPTION cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_TRACE_ON cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_PE_CONTEXT --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_EXCEPTION cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_TRACE_ON cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_PE_CONTEXT --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_INSTR_RANGE --->cs_etm_decoder_trace_element_callback: elem->elem_type OCSD_GEN_TRC_ELEM_EXCEPTION (gdb) thread 2 [Switching to thread 2 (Thread 0xb6ea7460 (LWP 8827))] #0 test (arg=0x0) at /home/ubuntu/development/gdb/build/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.btrace/multi-thread-step.c:34 34 global = 42; /* bp.2 */ (gdb) info record Active record target: record-btrace Recording format: arm Processor CoreSight ETM Trace. Buffer size: 8kB. Recorded 0 instructions in 0 functions (0 gaps) for thread 2 (Thread 0xb6ea7460 (LWP 8827)). (gdb) record function-call-history /ilc 1 No trace. (gdb)

is there any known issues for calling perf_event_open twice for two different threads?

is there any known issues for flushing traces when a switch between two threads takes place?

is there any known issue for tracing threads when switching happens due to a pthread_barrier_wait?