Running both tests cases 126 128 together causes the first test case
126 to fail:
 # for i in $(seq 3); do perf test 126 128; done
 126: perf trace BTF general tests    : FAILED!
 128: perf trace record and replay    : Ok
 126: perf trace BTF general tests    : FAILED!
 128: perf trace record and replay    : Ok
 126: perf trace BTF general tests    : FAILED!
 128: perf trace record and replay    : Ok
 #

Test case 126 fails because test case 128 runs concurrently as can
be observed using a ps -ef | grep perf output list on a different
window. Both do a perf trace command concurrently.
Make test case 126 exclusive and it works.

Output after:
 # for i in $(seq 3); do perf test 126 128; done
 126: perf trace exit race                           : Ok
 128: mmap interface tests                           :
 128.1: Read samples using the mmap interface        : Ok
 128.2: User space counter reading of instructions   : Ok
 128.3: User space counter reading of cycles         : Ok
 128.4: User space counter disabling instructions    : Ok
 128.5: User space counter disabling cycles          : Ok
 126: perf trace exit race                           : Ok
 128: mmap interface tests                           :
 128.1: Read samples using the mmap interface        : Ok
 128.2: User space counter reading of instructions   : Ok
 128.3: User space counter reading of cycles         : Ok
 128.4: User space counter disabling instructions    : Ok
 128.5: User space counter disabling cycles          : Ok
 126: perf trace exit race                           : Ok
 128: mmap interface tests                           :
 128.1: Read samples using the mmap interface        : Ok
 128.2: User space counter reading of instructions   : Ok
 128.3: User space counter reading of cycles         : Ok
 128.4: User space counter disabling instructions    : Ok
 128.5: User space counter disabling cycles          : Ok
 #

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Cc: Howard Chu <howardchu95@gmail.com>
---
 tools/perf/tests/shell/trace_btf_general.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/tests/shell/trace_btf_general.sh b/tools/perf/tests/shell/trace_btf_general.sh
index ef2da806be6b..7a94a5743924 100755
--- a/tools/perf/tests/shell/trace_btf_general.sh
+++ b/tools/perf/tests/shell/trace_btf_general.sh
@@ -1,5 +1,5 @@
 #!/bin/bash
-# perf trace BTF general tests
+# perf trace BTF general tests (exclusive)
 # SPDX-License-Identifier: GPL-2.0
 
 err=0
-- 
2.53.0