[patch 064/166] drivers/base/memory: map MMOP_OFFLINE to 0

Andrew Morton
2020-04-07T03:07:23Z

From: David Hildenbrand <david@redhat.com>
Subject: drivers/base/memory: map MMOP_OFFLINE to 0

Historically, we used the value -1. Just treat 0 as the special case now.
Clarify a comment (which was wrong, when we come via device_online() the
first time, the online_type would have been 0 / MEM_ONLINE). The default
is now always MMOP_OFFLINE. This removes the last user of the manual
"-1", which didn't use the enum value.

This is a preparation to use the online_type as an array index.

Link: http://lkml.kernel.org/r/20200317104942.11178-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Yumei Huang <yuhuang@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

drivers/base/memory.c | 11 ++++-------
include/linux/memory_hotplug.h | 2 +-
2 files changed, 5 insertions(+), 8 deletions(-)

--- a/drivers/base/memory.c~drivers-base-memory-map-mmop_offline-to-0
+++ a/drivers/base/memory.c
@@ -203,17 +203,14 @@ static int memory_subsys_online(struct d
return 0;

/*
- * If we are called from state_store(), online_type will be
- * set >= 0 Otherwise we were called from the device online
- * attribute and need to set the online_type.
+ * When called via device_online() without configuring the online_type,
+ * we want to default to MMOP_ONLINE.
*/
- if (mem->online_type < 0)
+ if (mem->online_type == MMOP_OFFLINE)
mem->online_type = MMOP_ONLINE;

ret = memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE);
-
- /* clear online_type */
- mem->online_type = -1;
+ mem->online_type = MMOP_OFFLINE;

return ret;
}
--- a/include/linux/memory_hotplug.h~drivers-base-memory-map-mmop_offline-to-0
+++ a/include/linux/memory_hotplug.h
@@ -48,7 +48,7 @@ enum {
/* Types for control the zone type of onlined and offlined memory */
enum {
/* Offline the memory. */
- MMOP_OFFLINE = -1,
+ MMOP_OFFLINE = 0,
/* Online the memory. Zone depends, see default_zone_for_pfn(). */
MMOP_ONLINE,
/* Online the memory to ZONE_NORMAL. */
_