[PATCH 1/2] add generic/585

[Dmitry Monakhov <dmonakhov@openvz.org>]

From: Dmitry Monakhov <dmtrmonakhov@yandex-team.ru>

Quotasync may livelock if others tasks generate enough dirty dquots in parallel
This test case pefrorm fchown to produce dirty quotas

This test known to detect livelock non-journaled quota for kernels prior to v5.4

Signed-off-by: Dmitry Monakhov <dmtrmonakhov@yandex-team.ru>
---
 src/Makefile          |   2 +-
 src/chowner.c         | 107 ++++++++++++++++++++++++++++++++++++++++++++++++++
 tests/generic/585     |  94 ++++++++++++++++++++++++++++++++++++++++++++
 tests/generic/585.out |   2 +
 tests/generic/group   |   1 +
 5 files changed, 205 insertions(+), 1 deletion(-)
 create mode 100644 src/chowner.c
 create mode 100755 tests/generic/585
 create mode 100644 tests/generic/585.out

diff --git a/src/Makefile b/src/Makefile
index ce6d861..b3ab7b4 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -28,7 +28,7 @@ LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \
 	attr-list-by-handle-cursor-test listxattr dio-interleaved t_dir_type \
 	dio-invalidate-cache stat_test t_encrypted_d_revalidate \
 	attr_replace_test swapon mkswap t_attr_corruption t_open_tmpfiles \
-	fscrypt-crypt-util bulkstat_null_ocount
+	fscrypt-crypt-util bulkstat_null_ocount chowner
 
 SUBDIRS = log-writes perf
 
diff --git a/src/chowner.c b/src/chowner.c
new file mode 100644
index 0000000..043cd06
--- /dev/null
+++ b/src/chowner.c
@@ -0,0 +1,107 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Copyright (c) 2019 YANDEX LLC.  All Rights Reserved.
+// Author: Dmitry Monakhov <dmtrmonakhov@yandex-team.ru>
+
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <sys/time.h>
+#include <fcntl.h>
+#include <limits.h>
+
+char *progname;
+
+void usage(void)
+{
+	printf("Usage %s: [-b uid] [-e uid] [-g] [-P] [-t timeout] FNAME\n", progname);
+	printf("\t\t -b: begin of uid range\n");
+	printf("\t\t -e: length of uid range\n");
+	printf("\t\t -g: change group uid\n");
+	printf("\t\t -t: loop timeout\n");
+	printf("\t\t -P: Do not run chowner loop, only prepare files\n");
+	exit(1);
+}
+int main(int argc, char *const *argv)
+{
+	char *filename;
+	int fd;
+	int c;
+	uid_t begin = 2000;
+	uid_t end = 12000;
+	unsigned int timeout = 10;
+	struct timeval start, now, delta = { 0, 0 };
+	uid_t uid;
+	gid_t gid = getegid();
+	int do_group = 0;
+	int do_prepare = 0;
+
+	progname = argv[0];
+	while ((c = getopt(argc, argv, "b:e:gPt:")) != -1) {
+		switch (c) {
+		case 'b':
+			begin = atoi(optarg);
+			break;
+		case 'e':
+			end = atoi(optarg);
+			break;
+		case 'g':
+			do_group = 1;
+			break;
+		case 'P':
+			do_prepare = 1;
+			break;
+		case 't':
+			timeout = atoi(optarg);
+			break;
+		default:
+			usage();
+		}
+	}
+	if (optind == argc-1)
+		filename = argv[optind];
+	else
+		usage();
+	if (do_prepare) {
+		char path[PATH_MAX];
+		for (uid = begin; uid < end;uid++) {
+			sprintf(path, "%s.%d", filename, uid);
+			fd = open(path, O_RDWR|O_CREAT, 0666);
+			if (fd < 0) {
+				perror("open");
+				exit(1);
+			}
+			if (do_group)
+				gid = uid;
+			if (fchown(fd, uid, gid)) {
+				perror("chown");
+				exit(1);
+			}
+			close(fd);
+		}
+		return 0;
+	}
+	fd = open(filename, O_RDWR|O_CREAT, 0666);
+	if (fd < 0) {
+		perror("open");
+		exit(1);
+	}
+	gettimeofday(&start, NULL);
+
+	while (1) {
+		for (uid = begin; uid < end;uid++) {
+			if (do_group)
+				gid = uid;
+			if (fchown(fd, uid, gid)) {
+				perror("chown");
+				exit(1);
+			}
+		}
+		gettimeofday(&now, NULL);
+		timersub(&now, &start, &delta);
+		if (delta.tv_sec >= timeout)
+			break;
+	}
+	return 0;
+}
diff --git a/tests/generic/585 b/tests/generic/585
new file mode 100755
index 0000000..d37522a
--- /dev/null
+++ b/tests/generic/585
@@ -0,0 +1,94 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2019 YANDEX LLC.  All Rights Reserved.
+#
+# FS QA Test 585
+#
+# Check livelock during quota-sync  while other tasks dirty quotas in parallel.
+# Run fchown(2) in a loop is the fastest way to produce dirty quotas
+#
+seq=`basename $0`
+seqres=$RESULT_DIR/$seq
+echo "QA output created by $seq"
+
+here=`pwd`
+tmp=/tmp/$$
+status=1	# failure is the default!
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+_cleanup()
+{
+	cd /
+	rm -f $tmp.*
+}
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+. ./common/quota
+
+
+begin=2000
+end=10000
+nr_proc=$((16 * LOAD_FACTOR))
+deadline=$((100 * TIME_FACTOR))
+
+_workout()
+{
+    for ((i=0; i < nr_proc; i++))
+    do
+	# Spread files to isolated dirs to minimize locking contention
+	mkdir -p $SCRATCH_MNT/chowner/$i
+	$here/src/chowner $SCRATCH_MNT/chowner/$i/test -b $begin -e $end \
+			  -t $((deadline + 10)) &
+	pids="$pids $!"
+    done
+    # Let chowners warm up ...
+    sleep 5
+    start=$(date +%s)
+    for ((i=0;i<3;i++))
+    do
+	s=$(date +%s)
+	# In normal situation command should finish in ~1sec,
+	# but in case of livelock it will spin until chowners exits
+	$*
+	e=$(date +%s)
+	echo "loop $i: $* runtime: $((e-s))" >> $seqres.full
+	sleep 2
+    done
+    end=$(date +%s)
+    runtime=$((end-start))
+    echo "DONE: $* total runtime: $runtime"  >> $seqres.full
+    kill -TERM $pids 2> /dev/null
+    wait $pids
+
+    [ $runtime -le $deadline ] || \
+	_fail "Live lock detected, $* runtime: $runtime, deadline: $deadline"
+}
+
+# real QA test starts here
+_supported_fs generic
+_supported_os Linux
+_require_quota
+#_require_user
+_require_scratch
+_require_command "$KILLALL_PROG" killall
+
+rm -f $seqres.full
+_scratch_mkfs_sized $((512 * 1024 * 1024)) >> $seqres.full 2>&1
+_scratch_mount "-o quota,user"
+chmod 777 $SCRATCH_MNT
+quotacheck -u $SCRATCH_MNT 2>/dev/null
+quotaon -v -u $SCRATCH_MNT >> $seqres.full 2>&1
+
+# Preparation step: Create all files with uid in range
+# to cache quota in kernel memory
+mkdir -p $SCRATCH_MNT/q
+$here/src/chowner $SCRATCH_MNT/q -b $begin -e $end -P
+
+_workout quotasync $SCRATCH_MNT
+_workout sync
+
+echo "Silence is golden"
+# success, all done
+status=0
+exit
diff --git a/tests/generic/585.out b/tests/generic/585.out
new file mode 100644
index 0000000..e4dd43b
--- /dev/null
+++ b/tests/generic/585.out
@@ -0,0 +1,2 @@
+QA output created by 585
+Silence is golden
diff --git a/tests/generic/group b/tests/generic/group
index 42ca2b9..703a1b4 100644
--- a/tests/generic/group
+++ b/tests/generic/group
@@ -587,3 +587,4 @@
 582 auto quick encrypt
 583 auto quick encrypt
 584 auto quick encrypt
+585 auto quota rw stress
-- 
2.7.4