On Fri, 26 Dec 2025 17:12:17 +0800 Fushuai Wang <[email protected]> wrote:
> 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. Never use "This patch" in a change log. See Submitting Patches: https://docs.kernel.org/process/submitting-patches.html#describe-your-changes Describe your changes in imperative mood, e.g. “make xyzzy do frotz” instead of “[This patch] makes xyzzy do frotz” or “[I] changed xyzzy to do frotz”, as if you are giving orders to the codebase to change its behaviour. > 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 <[email protected]> > --- > .../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"); Why are you doing this in the awk script? > 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 Could add: if ! test_multiple_writes ; then echo $ORIG > buffer_size_kb exit_fail fi instead. -- Steve > + > +echo $ORIG > buffer_size_kb
