diff options
Diffstat (limited to 'tools/testing/selftests/rcutorture')
| -rwxr-xr-x | tools/testing/selftests/rcutorture/bin/mkinitrd.sh | 43 |
1 files changed, 39 insertions, 4 deletions
diff --git a/tools/testing/selftests/rcutorture/bin/mkinitrd.sh b/tools/testing/selftests/rcutorture/bin/mkinitrd.sh index 87a87ffeaa85..b48c504edfe1 100755 --- a/tools/testing/selftests/rcutorture/bin/mkinitrd.sh +++ b/tools/testing/selftests/rcutorture/bin/mkinitrd.sh @@ -39,9 +39,22 @@ mkdir $T cat > $T/init << '__EOF___' #!/bin/sh +# Run in userspace a few milliseconds every second. This helps to +# exercise the NO_HZ_FULL portions of RCU. while : do - sleep 1000000 + q= + for i in \ + a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a \ + a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a \ + a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a \ + a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a \ + a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a \ + a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a + do + q="$q $i" + done + sleep 1 done __EOF___ @@ -70,15 +83,37 @@ mkdir initrd cd initrd cat > init.c << '___EOF___' #include <unistd.h> +#include <sys/time.h> + +volatile unsigned long delaycount; int main(int argc, int argv[]) { - for (;;) - sleep(1000*1000*1000); /* One gigasecond is ~30 years. */ + int i; + struct timeval tv; + struct timeval tvb; + + for (;;) { + sleep(1); + /* Need some userspace time. */ + if (gettimeofday(&tvb, NULL)) + continue; + do { + for (i = 0; i < 1000 * 100; i++) + delaycount = i * i; + if (gettimeofday(&tv, NULL)) + break; + tv.tv_sec -= tvb.tv_sec; + if (tv.tv_sec > 1) + break; + tv.tv_usec += tv.tv_sec * 1000 * 1000; + tv.tv_usec -= tvb.tv_usec; + } while (tv.tv_usec < 1000); + } return 0; } ___EOF___ -gcc -static -Os -o init init.c +cc -static -Os -o init init.c strip init rm init.c echo "Done creating a statically linked C-language initrd" |