When /sys/kernel/tracing/buffer_size_kb is less than 12KB, the test_multiple_writes test will stall and wait for more input due to insufficient buffer space.

This patch check current buffer_size_kb value before the test. If it is less than 12KB, it temporarily increase the buffer to 12KB, and restore the original value after the tests are completed.

Fixes: 37f46601383a ("selftests/tracing: Add basic test for trace_marker_raw file") Signed-off-by: Fushuai Wang wangfushuai@baidu.com --- .../ftrace/test.d/00basic/trace_marker_raw.tc | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/ftrace/test.d/00basic/trace_marker_raw.tc b/tools/testing/selftests/ftrace/test.d/00basic/trace_marker_raw.tc index 7daf7292209e..216f87d89c3f 100644 --- a/tools/testing/selftests/ftrace/test.d/00basic/trace_marker_raw.tc +++ b/tools/testing/selftests/ftrace/test.d/00basic/trace_marker_raw.tc @@ -58,7 +58,7 @@ test_multiple_writes() { echo stop > trace_marker

# Check to make sure the number of entries is the id (rounded up by 4) - awk '/.*: # [0-9a-f]* / { + awk -v ORIG="${ORIG}" '/.*: # [0-9a-f]* / { print; cnt = -1; for (i = 0; i < NF; i++) { @@ -70,6 +70,7 @@ test_multiple_writes() { # The number of items is always rounded up by 4 cnt2 = int((cnt + 3) / 4) * 4; if (cnt2 != num) { + system("echo ""ORIG"" > buffer_size_kb"); exit 1; } break; @@ -89,6 +90,7 @@ test_buffer() { # The id must be four bytes, test that 3 bytes fails a write if echo -n abc > ./trace_marker_raw ; then echo "Too small of write expected to fail but did not" + echo $ORIG > buffer_size_kb exit_fail fi

@@ -99,9 +101,21 @@ test_buffer() {

if write_buffer 0xdeadbeef $size ; then echo "Too big of write expected to fail but did not" + echo $ORIG > buffer_size_kb exit_fail fi }

+ORIG=`cat buffer_size_kb` + +# test_multiple_writes test needs at least 12KB buffer +NEW_SIZE=12 + +if [ ${ORIG} -lt ${NEW_SIZE} ]; then + echo ${NEW_SIZE} > buffer_size_kb +fi + test_buffer test_multiple_writes + +echo $ORIG > buffer_size_kb