mm: memcontrol: use "max" instead of "infinity" in control knobs

The memcg control knobs indicate the highest possible value using the
symbolic name "infinity", which is long and awkward to type.

Switch to the string "max", which is just as descriptive but shorter and
sweeter.

This changes a user interface, so do it before the release and before
the development flag is dropped from the default hierarchy.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 76c5a1b..9fe0769 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -5247,7 +5247,7 @@
 	unsigned long low = ACCESS_ONCE(memcg->low);
 
 	if (low == PAGE_COUNTER_MAX)
-		seq_puts(m, "infinity\n");
+		seq_puts(m, "max\n");
 	else
 		seq_printf(m, "%llu\n", (u64)low * PAGE_SIZE);
 
@@ -5262,7 +5262,7 @@
 	int err;
 
 	buf = strstrip(buf);
-	err = page_counter_memparse(buf, "infinity", &low);
+	err = page_counter_memparse(buf, "max", &low);
 	if (err)
 		return err;
 
@@ -5277,7 +5277,7 @@
 	unsigned long high = ACCESS_ONCE(memcg->high);
 
 	if (high == PAGE_COUNTER_MAX)
-		seq_puts(m, "infinity\n");
+		seq_puts(m, "max\n");
 	else
 		seq_printf(m, "%llu\n", (u64)high * PAGE_SIZE);
 
@@ -5292,7 +5292,7 @@
 	int err;
 
 	buf = strstrip(buf);
-	err = page_counter_memparse(buf, "infinity", &high);
+	err = page_counter_memparse(buf, "max", &high);
 	if (err)
 		return err;
 
@@ -5307,7 +5307,7 @@
 	unsigned long max = ACCESS_ONCE(memcg->memory.limit);
 
 	if (max == PAGE_COUNTER_MAX)
-		seq_puts(m, "infinity\n");
+		seq_puts(m, "max\n");
 	else
 		seq_printf(m, "%llu\n", (u64)max * PAGE_SIZE);
 
@@ -5322,7 +5322,7 @@
 	int err;
 
 	buf = strstrip(buf);
-	err = page_counter_memparse(buf, "infinity", &max);
+	err = page_counter_memparse(buf, "max", &max);
 	if (err)
 		return err;