* tests/nproc/nproc-quota.sh: Prefer strace to LD_PRELOAD,
as it's simpler and supports static executables.
https://github.com/coreutils/coreutils/issues/309
---
tests/nproc/nproc-quota.sh | 58 ++++++++------------------------------
1 file changed, 11 insertions(+), 47 deletions(-)
diff --git a/tests/nproc/nproc-quota.sh b/tests/nproc/nproc-quota.sh
index f5f67565f..e8c24bcde 100755
--- a/tests/nproc/nproc-quota.sh
+++ b/tests/nproc/nproc-quota.sh
@@ -19,53 +19,14 @@
. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
print_ver_ nproc
require_root_
-require_gcc_shared_
+uses_strace_
-# Replace sched_getscheduler()
-cat > k.c <<'EOF' || framework_failure_
-#include <stdio.h>
-#include <errno.h>
-#define __USE_GNU /* For SCHED_DEADLINE. */
-#include <sched.h>
-
-int
-sched_getscheduler (pid_t pid)
-{
- fclose (fopen ("preloaded","w")); /* marker for preloaded interception */
- FILE *policyf = fopen ("/proc/self/sched", "r");
- int policy;
- #define fscanfmt fscanf /* Avoid syntax check. */
- if (pid == 0 && fscanfmt (policyf, "policy : %d", &policy) == 1)
- {
- switch (policy)
- {
- case 0: return SCHED_OTHER;
- case 1: return SCHED_FIFO;
- case 2: return SCHED_RR;
- case 6: return SCHED_DEADLINE;
- case -1: errno = EINVAL; return -1;
- default: return SCHED_OTHER;
- }
- }
- else
- {
- errno = ENOSYS;
- return -1;
- }
-}
-EOF
-
-# compile/link the interception shared library:
-gcc_shared_ k.c k.so \
- || skip_ 'failed to build sched_getscheduler shared library'
-
-(export LD_PRELOAD=$LD_PRELOAD:./k.so
- nproc) || fail=1
-
-# Ensure our wrapper is in place and is called
-# I.e., this test is restricted to new enough Linux systems
+# Ensure new enough Linux systems
# as otherwise cpu_quota() will not call sched_getscheduler()
-test -e preloaded || skip_ 'LD_PRELOAD interception failed'
+strace -o getsched_count -e sched_getscheduler nproc
+getsched_count=$(grep '^sched_getscheduler' getsched_count | wc -l)
+test "$getsched_count" -ge 1 ||
+ skip_ 'sched_getscheduler() call not detected'
# We could look for modifiable cgroup quotas on the current system,
# but that would be dangerous to modify and restore robustly.
@@ -87,9 +48,12 @@ nproc=$abs_top_builddir/src/nproc$EXEEXT
cp --parents $(ldd $nproc | grep -o '/[^ ]*') $ROOT ||
skip_ 'Failed to copy nproc libs to chroot'
cp $nproc $ROOT || framework_failure_
-cp k.so $ROOT || framework_failure_
-NPROC() { LD_PRELOAD=$LD_PRELOAD:./k.so chroot $ROOT /nproc "$@"; }
+NPROC() {
+ IFS=': ' read key policy < $ROOT/proc/self/sched
+ strace -o /dev/null -qqq -e inject=sched_getscheduler:retval=$policy \
+ chroot $ROOT /nproc "$@"
+}
NPROC --version ||
skip_ 'Failed to execute nproc in chroot'
--
2.54.0
