From 757403191c37db75ed35b02c971846dced5d5119 Mon Sep 17 00:00:00 2001
From: Nikitas Angelinas <nangelinas@cray.com>
Date: Thu, 29 Nov 2018 15:23:05 -0800
Subject: [PATCH] LU-11721 utils: print used inodes ratio when using "lfs df
 -i"

"lfs df -i" prints the used blocks percentage, instead of the used
inodes percentage. Fix this by allowing obd_statfs_ratio() to
distinguish when "-i" is used.

Round up the ratio returned from obd_statfs_ratio() in a ceiling
manner, to match the output of df(1). Add a sanity test to check
that the outputs from df(1) and lfs df match.

Signed-off-by: Nikitas Angelinas <nangelinas@cray.com>
Cray-bug-id: LUS-6748
Test-Parameters: trivial
Change-Id: I0b31ecb7371875c93bc07dda1f1c89e04d5b4576
Reviewed-on: https://review.whamcloud.com/33758
Tested-by: Jenkins
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Lai Siyao <lai.siyao@whamcloud.com>
---
 lustre/tests/sanity.sh | 76 ++++++++++++++++++++++++++++++++++++++++++++++++++
 lustre/utils/lfs.c     | 26 ++++++++++-------
 2 files changed, 92 insertions(+), 10 deletions(-)

diff --git a/lustre/tests/sanity.sh b/lustre/tests/sanity.sh
index c0a3eb4..ec6ae03 100755
--- a/lustre/tests/sanity.sh
+++ b/lustre/tests/sanity.sh
@@ -19359,6 +19359,82 @@ test_417() {
 }
 run_test 417 "disable remote dir, striped dir and dir migration"
 
+# Checks that the outputs of df [-i] and lfs df [-i] match
+#
+# usage: check_lfs_df <blocks | inodes> <mountpoint>
+check_lfs_df() {
+	local dir=$2
+	local inodes
+	local df_out
+	local lfs_df_out
+
+	# blocks or inodes
+	[ "$1" == "blocks" ] && inodes= || inodes="-i"
+
+	# read the lines of interest
+	df_out=($(df $inodes $dir | tail -n +2)) ||
+		error "df $inodes $dir | tail -n +2 failed"
+	lfs_df_out=($($LFS df $inodes $dir | grep filesystem_summary:)) ||
+		error "lfs df $inodes $dir | grep filesystem_summary: failed"
+
+	# skip the first substrings of each command output as they are different
+	# <NID>:/<fsname for df, filesystem_summary: for lfs df
+	df_out=(${df_out[@]:1})
+	lfs_df_out=(${lfs_df_out[@]:1})
+
+	# compare the two outputs
+	for i in {0..4}; do
+		[ "${df_out[i]}" != "${lfs_df_out[i]}" ] &&
+			error "df and lfs df output mismatch:" \
+			      "df${inodes}: ${df_out[*]}," \
+			      "lfs df${inodes}: ${lfs_df_out[*]}"
+	done
+}
+
+test_418() {
+	local dir=$DIR/$tdir
+	local numfiles=$((RANDOM % 4096 + 2))
+	local numblocks=$((RANDOM % 256 + 1))
+
+	wait_delete_completed
+	test_mkdir $dir
+
+	# check block output
+	check_lfs_df blocks $dir
+	# check inode output
+	check_lfs_df inodes $dir
+
+	# create a single file and retest
+	echo "Creating a single file and testing"
+	createmany -o $dir/$tfile- 1 &>/dev/null ||
+		error "creating 1 file in $dir failed"
+	cancel_lru_locks osc
+	sync; sleep 2
+	check_lfs_df blocks $dir
+	check_lfs_df inodes $dir
+
+	# create a random number of files
+	echo "Creating $((numfiles - 1)) files and testing"
+	createmany -o $dir/$tfile- 1 $((numfiles - 1)) &>/dev/null ||
+		error "creating $((numfiles - 1)) files in $dir failed"
+
+	# write a random number of blocks to the first test file
+	echo "Writing $numblocks 4K blocks and testing"
+	dd if=/dev/urandom of=$dir/${tfile}-0 bs=4K conv=fsync \
+		count=$numblocks &>/dev/null ||
+		error "dd to $dir/${tfile}-0 failed"
+
+	# retest
+	cancel_lru_locks osc
+	sync; sleep 10
+	check_lfs_df blocks $dir
+	check_lfs_df inodes $dir
+
+	unlinkmany $dir/$tfile- $numfiles &>/dev/null ||
+		error "unlinking $numfiles files in $dir failed"
+}
+run_test 418 "df and lfs df outputs match"
+
 prep_801() {
 	[[ $(lustre_version_code mds1) -lt $(version_code 2.9.55) ]] ||
 	[[ $OST1_VERSION -lt $(version_code 2.9.55) ]] &&
diff --git a/lustre/utils/lfs.c b/lustre/utils/lfs.c
index 63d4aa4..6225437 100644
--- a/lustre/utils/lfs.c
+++ b/lustre/utils/lfs.c
@@ -4606,16 +4606,22 @@ enum mntdf_flags {
 #define RSF     "%4s"
 #define RDF     "%3d%%"
 
-static inline int obd_statfs_ratio(const struct obd_statfs *st)
+static inline int obd_statfs_ratio(const struct obd_statfs *st, bool inodes)
 {
 	double avail, used, ratio = 0;
 
-	avail = st->os_bavail;
-	used  = st->os_blocks - st->os_bfree;
+	if (inodes) {
+		avail = st->os_ffree;
+		used = st->os_files - st->os_ffree;
+	} else {
+		avail = st->os_bavail;
+		used = st->os_blocks - st->os_bfree;
+	}
 	if (avail + used > 0)
-		ratio = used / (used + avail) * 100 + 0.5;
+		ratio = used / (used + avail) * 100;
 
-	return (int)ratio;
+	/* Round up to match df(1) usage percentage */
+	return (ratio - (int)ratio) > 0 ? (int)(ratio + 1) : (int)ratio;
 }
 
 static int showdf(char *mntdir, struct obd_statfs *stat,
@@ -4649,7 +4655,7 @@ static int showdf(char *mntdir, struct obd_statfs *stat,
 			total = (stat->os_blocks * stat->os_bsize) >> shift;
 		}
 
-		ratio = obd_statfs_ratio(stat);
+		ratio = obd_statfs_ratio(stat, flags & MNTDF_INODES);
 
 		if (flags & MNTDF_COOKED) {
 			int i;
@@ -4893,8 +4899,8 @@ static int ll_statfs_data_comp(const void *sd1, const void *sd2)
 						sd_st;
 	const struct obd_statfs *st2 = &((const struct ll_statfs_data *)sd2)->
 						sd_st;
-	int r1 = obd_statfs_ratio(st1);
-	int r2 = obd_statfs_ratio(st2);
+	int r1 = obd_statfs_ratio(st1, false);
+	int r2 = obd_statfs_ratio(st2, false);
 	int64_t result = r1 - r2;
 
 	/* if both space usage are above 90, compare free inodes */
@@ -5174,8 +5180,8 @@ static int lfs_setdirstripe(int argc, char **argv)
 
 				/* don't use server whose usage is above 90% */
 				while (nr != param->lsp_stripe_count &&
-				       obd_statfs_ratio(&lsb->sb_buf[nr].sd_st)
-				       > 90)
+				       obd_statfs_ratio(&lsb->sb_buf[nr].sd_st,
+							false) > 90)
 					nr = MAX(param->lsp_stripe_count,
 						 nr / 2);
 
-- 
1.8.3.1