[RFC][PATCH 4/5] Memory controller soft limit refactor reclaim flags (v9)

Balbir Singh
2009-07-10T12:36:02Z

Impact: Refactor mem_cgroup_hierarchical_reclaim()

From: Balbir Singh <balbir@linux.vnet.ibm.com>

This patch refactors the arguments passed to
mem_cgroup_hierarchical_reclaim() into flags, so that new parameters don't
have to be passed as we make the reclaim routine more flexible

Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
---

mm/memcontrol.c | 25 +++++++++++++++++++------
1 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 219b060..1421576 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -252,6 +252,14 @@ enum charge_type {
#define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff)
#define MEMFILE_ATTR(val) ((val) & 0xffff)

+/*
+ * Reclaim flags for mem_cgroup_hierarchical_reclaim
+ */
+#define MEM_CGROUP_RECLAIM_NOSWAP_BIT 0x0
+#define MEM_CGROUP_RECLAIM_NOSWAP (1 << MEM_CGROUP_RECLAIM_NOSWAP_BIT)
+#define MEM_CGROUP_RECLAIM_SHRINK_BIT 0x1
+#define MEM_CGROUP_RECLAIM_SHRINK (1 << MEM_CGROUP_RECLAIM_SHRINK_BIT)
+
static void mem_cgroup_get(struct mem_cgroup *mem);
static void mem_cgroup_put(struct mem_cgroup *mem);
static struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *mem);
@@ -1031,11 +1039,14 @@ mem_cgroup_select_victim(struct mem_cgroup *root_mem)
* If shrink==true, for avoiding to free too much, this returns immedieately.
*/
static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_mem,
- gfp_t gfp_mask, bool noswap, bool shrink)
+ gfp_t gfp_mask,
+ unsigned long reclaim_options)
{
struct mem_cgroup *victim;
int ret, total = 0;
int loop = 0;
+ bool noswap = reclaim_options & MEM_CGROUP_RECLAIM_NOSWAP;
+ bool shrink = reclaim_options & MEM_CGROUP_RECLAIM_SHRINK;

/* If memsw_is_minimum==1, swap-out is of-no-use. */
if (root_mem->memsw_is_minimum)
@@ -1173,7 +1184,7 @@ static int __mem_cgroup_try_charge(struct mm_struct *mm,

while (1) {
int ret;
- bool noswap = false;
+ unsigned long flags = 0;

ret = res_counter_charge(&mem->res, PAGE_SIZE, &fail_res,
&soft_fail_res);
@@ -1186,7 +1197,7 @@ static int __mem_cgroup_try_charge(struct mm_struct *mm,
break;
/* mem+swap counter fails */
res_counter_uncharge(&mem->res, PAGE_SIZE, NULL);
- noswap = true;
+ flags |= MEM_CGROUP_RECLAIM_NOSWAP;
mem_over_limit = mem_cgroup_from_res_counter(fail_res,
memsw);
} else
@@ -1198,7 +1209,7 @@ static int __mem_cgroup_try_charge(struct mm_struct *mm,
goto nomem;

ret = mem_cgroup_hierarchical_reclaim(mem_over_limit, gfp_mask,
- noswap, false);
+ flags);
if (ret)
continue;

@@ -1993,7 +2004,7 @@ static int mem_cgroup_resize_limit(struct mem_cgroup *memcg,
break;

progress = mem_cgroup_hierarchical_reclaim(memcg, GFP_KERNEL,
- false, true);
+ MEM_CGROUP_RECLAIM_SHRINK);
curusage = res_counter_read_u64(&memcg->res, RES_USAGE);
/* Usage is reduced ? */
if (curusage >= oldusage)
@@ -2045,7 +2056,9 @@ static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg,
if (!ret)
break;

- mem_cgroup_hierarchical_reclaim(memcg, GFP_KERNEL, true, true);
+ mem_cgroup_hierarchical_reclaim(memcg, GFP_KERNEL,
+ MEM_CGROUP_RECLAIM_NOSWAP |
+ MEM_CGROUP_RECLAIM_SHRINK);
curusage = res_counter_read_u64(&memcg->memsw, RES_USAGE);
/* Usage is reduced ? */
if (curusage >= oldusage)