perf test: Replace arm spe fork test workload with sqrtloop

So that it can get rid of requirement of a compiler.  I've also removed
killall as it'll kill perf process now and run the test workload for 10
sec instead.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: James Clark <james.clark@arm.com>
Tested-by: Leo Yan <leo.yan@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Zhengjun Xing <zhengjun.xing@linux.intel.com>
Link: https://lore.kernel.org/r/20221116233854.1596378-9-namhyung@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/tests/shell/test_arm_spe_fork.sh

@@ -11,14 +11,7 @@ skip_if_no_arm_spe_event() {
 
 skip_if_no_arm_spe_event || exit 2
 
-# skip if there's no compiler
-if ! [ -x "$(command -v cc)" ]; then
-	echo "failed: no compiler, install gcc"
-	exit 2
-fi
-
-TEST_PROGRAM_SOURCE=$(mktemp /tmp/__perf_test.program.XXXXX.c)
-TEST_PROGRAM=$(mktemp /tmp/__perf_test.program.XXXXX)
+TEST_PROGRAM="perf test -w sqrtloop 10"
 PERF_DATA=$(mktemp /tmp/__perf_test.perf.data.XXXXX)
 PERF_RECORD_LOG=$(mktemp /tmp/__perf_test.log.XXXXX)
 
@@ -27,43 +20,10 @@ cleanup_files()
 	echo "Cleaning up files..."
 	rm -f ${PERF_RECORD_LOG}
 	rm -f ${PERF_DATA}
-	rm -f ${TEST_PROGRAM_SOURCE}
-	rm -f ${TEST_PROGRAM}
 }
 
 trap cleanup_files exit term int
 
-# compile test program
-cat << EOF > $TEST_PROGRAM_SOURCE
-#include <math.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <sys/wait.h>
-
-int workload() {
-  while (1)
-    sqrt(rand());
-  return 0;
-}
-
-int main() {
-  switch (fork()) {
-    case 0:
-      return workload();
-    case -1:
-      return 1;
-    default:
-      wait(NULL);
-  }
-  return 0;
-}
-EOF
-
-echo "Compiling test program..."
-CFLAGS="-lm"
-cc $TEST_PROGRAM_SOURCE $CFLAGS -o $TEST_PROGRAM || exit 1
-
 echo "Recording workload..."
 perf record -o ${PERF_DATA} -e arm_spe/period=65536/ -vvv -- $TEST_PROGRAM > ${PERF_RECORD_LOG} 2>&1 &
 PERFPID=$!
@@ -78,8 +38,6 @@ echo Log lines after 1 second = $log1
 
 kill $PERFPID
 wait $PERFPID
-# test program may leave an orphan process running the workload
-killall $(basename $TEST_PROGRAM)
 
 if [ "$log0" = "$log1" ];
 then