[PATCH v3 14/16] perf test trace_btf_general: Drop --max-events=1 and make non-exclusive

[Ian Rogers <irogers@google.com>]

trace_btf_general.sh used `--max-events=1` with `perf trace` on
commands such as `mv`, `echo`, and `sleep`. When background activity
occurs or tests run in parallel, `perf trace` can capture an event
from an unrelated process and exit prematurely before recording the
target command's syscalls.

Drop `--max-events=1` and let tracing run until the command completes,
checking for the expected output with grep (matching trace_btf_enum.sh).
Remove the (exclusive) tag so the test runs in parallel.

Running perf trace in parallel is only safe now that the probe tests no
longer name their probes "vfs_getname...": perf trace opens everything
matching a hardcoded "probe:vfs_getname*" wildcard, which used to pin
those probes and make their cleanup fail with -EBUSY.

Assisted-by: Antigravity:gemini-3.1-pro
Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/tests/shell/trace_btf_general.sh | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/tools/perf/tests/shell/trace_btf_general.sh b/tools/perf/tests/shell/trace_btf_general.sh
index 7a94a5743924..4d654b687a4e 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 (exclusive)
+# perf trace BTF general tests
 # SPDX-License-Identifier: GPL-2.0
 
 err=0
@@ -27,7 +27,7 @@ check_vmlinux() {
 
 trace_test_string() {
   echo "Testing perf trace's string augmentation"
-  output="$(perf trace --sort-events -e renameat* --max-events=1 -- mv ${file1} ${file2} 2>&1)"
+  output="$(perf trace --sort-events -e renameat* -- mv ${file1} ${file2} 2>&1)"
   if ! echo "$output" | grep -q -E "^mv/[0-9]+ renameat(2)?\(.*, \"${file1}\", .*, \"${file2}\", .*\) += +[0-9]+$"
   then
     printf "String augmentation test failed, output:\n$output\n"
@@ -38,7 +38,7 @@ trace_test_string() {
 trace_test_buffer() {
   echo "Testing perf trace's buffer augmentation"
   # echo will insert a newline (\10) at the end of the buffer
-  output="$(perf trace --sort-events -e write --max-events=1 -- echo "${buffer}" 2>&1)"
+  output="$(perf trace --sort-events -e write -- echo "${buffer}" 2>&1)"
   if ! echo "$output" | grep -q -E "^echo/[0-9]+ write\([0-9]+, ${buffer}.*, [0-9]+\) += +[0-9]+$"
   then
     printf "Buffer augmentation test failed, output:\n$output\n"
@@ -48,7 +48,7 @@ trace_test_buffer() {
 
 trace_test_struct_btf() {
   echo "Testing perf trace's struct augmentation"
-  output="$(perf trace --sort-events -e clock_nanosleep --force-btf --max-events=1 -- sleep 1 2>&1)"
+  output="$(perf trace --sort-events -e clock_nanosleep --force-btf -- sleep 1 2>&1)"
   if ! echo "$output" | grep -q -E "^sleep/[0-9]+ clock_nanosleep\(0, 0, \{1,.*\}, 0x[0-9a-f]+\) += +[0-9]+$"
   then
 	printf "BTF struct augmentation test failed, output:\n$output\n"
-- 
2.55.0.1082.g2b9226bbc0-goog