On Wed 04-04-12 20:19:18, David Rientjes wrote:
> linux-next fails with this
>
> mm/memcontrol.c: In function '__mem_cgroup_commit_charge_swapin':
> mm/memcontrol.c:2837: error: implicit declaration of function 'mem_cgroup_uncharge_swap'
>
> if CONFIG_SWAP is disabled. Fix it.
Although this is correct maybe it would be better to move the definition
outside the CONFIG_SWAP to prevent from duplication
What do you think about the following?
---
>From 8ba60924d956883eb2e0ef0991a62f5f6e7cf6c7 Mon Sep 17 00:00:00 2001
From: Michal Hocko <mhocko@xxxxxxx>
Date: Thu, 5 Apr 2012 07:26:48 -0700
Subject: [PATCH] memcg swap: use mem_cgroup_uncharge_swap fix
Although mem_cgroup_uncharge_swap has an empty placeholder for
!CONFIG_CGROUP_MEM_RES_CTLR_SWAP the definition is placed in the
CONFIG_SWAP ifdef block so we are missing the same definition for
!CONFIG_SWAP which implies !CONFIG_CGROUP_MEM_RES_CTLR_SWAP.
This was not an issue until "memcg swap: use mem_cgroup_uncharge_swap()"
because mem_cgroup_uncharge_swap was not called from !CONFIG_SWAP
context but now we are calling it from __mem_cgroup_commit_charge_swapin
which is defined also for !CONFIG_SWAP.
Let's move both the empty definition and declaration outside of the
CONFIG_SWAP block to fix the following compilation error:
mm/memcontrol.c: In function '__mem_cgroup_commit_charge_swapin':
mm/memcontrol.c:2837: error: implicit declaration of function 'mem_cgroup_uncharge_swap'
if CONFIG_SWAP is disabled.
Reported-by: David Rientjes <rientjes@xxxxxxxxxx>
Signed-off-by: Michal Hocko <mhocko@xxxxxxx>
---
include/linux/swap.h | 14 +++++++-------
1 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/include/linux/swap.h b/include/linux/swap.h
index 3e60228..b3caade 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -301,6 +301,13 @@ static inline int mem_cgroup_swappiness(struct mem_cgroup *mem)
return vm_swappiness;
}
#endif
+#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
+extern void mem_cgroup_uncharge_swap(swp_entry_t ent);
+#else
+static inline void mem_cgroup_uncharge_swap(swp_entry_t ent)
+{
+}
+#endif
#ifdef CONFIG_SWAP
/* linux/mm/page_io.c */
extern int swap_readpage(struct page *);
@@ -372,13 +379,6 @@ mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent, bool swapout)
{
}
#endif
-#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
-extern void mem_cgroup_uncharge_swap(swp_entry_t ent);
-#else
-static inline void mem_cgroup_uncharge_swap(swp_entry_t ent)
-{
-}
-#endif
#else /* CONFIG_SWAP */
--
1.7.9.1
--
Michal Hocko
SUSE Labs
SUSE LINUX s.r.o.
Lihovarska 1060/12
190 00 Praha 9
Czech Republic
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>