Thread (11 messages) flat view 11 messages, 3 authors, 2017-07-19

Re: [PATCH 1/9] mm, page_alloc: rip out ZONELIST_ORDER_ZONE

From: Mel Gorman <mgorman@suse.de>
Date: 2017-07-14 12:56:26
Also in: linux-mm, lkml

On Fri, Jul 14, 2017 at 01:38:40PM +0200, Michal Hocko wrote:
quoted hunk ↗ jump to hunk
On Fri 14-07-17 12:16:33, Mel Gorman wrote:
quoted
On Fri, Jul 14, 2017 at 12:47:57PM +0200, Michal Hocko wrote:
quoted
quoted
That should to be "default" because the original code would have the proc
entry display "default" unless it was set at runtime. Pretty weird I
know but it's always possible someone is parsing the original default
and not handling it properly.
Ohh, right! That is indeed strange. Then I guess it would be probably
better to simply return Node to make it clear what the default is. What
do you think?
That would work too. The casing still matches.
This folded in?
---
From c7c36f011590680b254813be00ed791ddbc1bf1c Mon Sep 17 00:00:00 2001
From: Michal Hocko <mhocko@suse.com>
Date: Fri, 14 Jul 2017 13:36:05 +0200
Subject: [PATCH] fold me "mm, page_alloc: rip out ZONELIST_ORDER_ZONE"

- do not print Default in sysctl handler because our behavior was rather
inconsistent in the past numa_zonelist_order was lowecase while
zonelist_order_name was uppercase so boot time unchanged value woul
print lowercase while updated value could be uppercase. Print "Node"
which is the default instead - Mel

Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 mm/page_alloc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index dd4c96edcec3..49bade7ff049 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -4828,8 +4828,8 @@ int numa_zonelist_order_handler(struct ctl_table *table, int write,
 	int ret;
 
 	if (!write) {
-		int len = sizeof("Default");
-		if (copy_to_user(buffer, "Default", len))
+		int len = sizeof("Node");
+		if (copy_to_user(buffer, "Node", len))
 			return -EFAULT;
Ok for the name. But what's with using sizeof? The type is char * so it
just happens to work for Default, but not for Node. Also strongly suggest
you continue using proc_dostring because it catches all the corner-cases
that can occur.

-- 
Mel Gorman
SUSE Labs

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help