tools/vm/slabinfo: add option to sort by partial slabs

We would like to get a better view of the level of fragmentation within
the SLUB allocator.  Total number of partial slabs is an indicator of
fragmentation.

Add a command line option (-P | --partial) to sort the slab list by total
number of partial slabs.

Link: http://lkml.kernel.org/r/20190426022622.4089-4-tobin@kernel.org
Signed-off-by: Tobin C. Harding <tobin@kernel.org>
Cc: Alexander Duyck <alexander.duyck@gmail.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>,
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Pekka Enberg <penberg@iki.fi>
Cc: Qian Cai <cai@lca.pw>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

tools/vm/slabinfo.c

@@ -111,7 +111,7 @@ static void fatal(const char *x, ...)
 static void usage(void)
 {
 	printf("slabinfo 4/15/2011. (c) 2007 sgi/(c) 2011 Linux Foundation.\n\n"
-		"slabinfo [-aABDefhilLnorsStTUvXz1] [N=K] [-dafzput] [slab-regexp]\n"
+		"slabinfo [-aABDefhilLnoPrsStTUvXz1] [N=K] [-dafzput] [slab-regexp]\n"
 		"-a|--aliases           Show aliases\n"
 		"-A|--activity          Most active slabs first\n"
 		"-B|--Bytes             Show size in bytes\n"
@@ -125,6 +125,7 @@ static void usage(void)
 		"-n|--numa              Show NUMA information\n"
 		"-N|--lines=K           Show the first K slabs\n"
 		"-o|--ops               Show kmem_cache_ops\n"
+		"-P|--partial		Sort by number of partial slabs\n"
 		"-r|--report            Detailed report on single slabs\n"
 		"-s|--shrink            Shrink slabs\n"
 		"-S|--Size              Sort by size\n"
@@ -1361,6 +1362,7 @@ struct option opts[] = {
 	{ "numa", no_argument, NULL, 'n' },
 	{ "lines", required_argument, NULL, 'N'},
 	{ "ops", no_argument, NULL, 'o' },
+	{ "partial", no_argument, NULL, 'p'},
 	{ "report", no_argument, NULL, 'r' },
 	{ "shrink", no_argument, NULL, 's' },
 	{ "Size", no_argument, NULL, 'S'},
@@ -1382,7 +1384,7 @@ int main(int argc, char *argv[])
 
 	page_size = getpagesize();
 
-	while ((c = getopt_long(argc, argv, "aABd::DefhilLnN:orsStTUvXz1",
+	while ((c = getopt_long(argc, argv, "aABd::DefhilLnN:oPrsStTUvXz1",
 						opts, NULL)) != -1)
 		switch (c) {
 		case 'a':
@@ -1436,6 +1438,9 @@ int main(int argc, char *argv[])
 		case 'r':
 			show_report = 1;
 			break;
+		case 'P':
+			sort_partial = 1;
+			break;
 		case 's':
 			shrink = 1;
 			break;