memcg: clean up existing move charge code
- Replace lengthy function name is_target_pte_for_mc() with a shorter
one in order to avoid ugly line breaks.
- explicitly use MC_TARGET_* instead of simply using integers.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Acked-by: Hillf Danton <dhillf@gmail.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 6110293..c8d00a9 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -5110,7 +5110,7 @@
}
/**
- * is_target_pte_for_mc - check a pte whether it is valid for move charge
+ * get_mctgt_type - get target type of moving charge
* @vma: the vma the pte to be checked belongs
* @addr: the address corresponding to the pte to be checked
* @ptent: the pte to be checked
@@ -5133,7 +5133,7 @@
};
enum mc_target_type {
- MC_TARGET_NONE, /* not used */
+ MC_TARGET_NONE = 0,
MC_TARGET_PAGE,
MC_TARGET_SWAP,
};
@@ -5214,12 +5214,12 @@
return page;
}
-static int is_target_pte_for_mc(struct vm_area_struct *vma,
+static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma,
unsigned long addr, pte_t ptent, union mc_target *target)
{
struct page *page = NULL;
struct page_cgroup *pc;
- int ret = 0;
+ enum mc_target_type ret = MC_TARGET_NONE;
swp_entry_t ent = { .val = 0 };
if (pte_present(ptent))
@@ -5230,7 +5230,7 @@
page = mc_handle_file_pte(vma, addr, ptent, &ent);
if (!page && !ent.val)
- return 0;
+ return ret;
if (page) {
pc = lookup_page_cgroup(page);
/*
@@ -5270,7 +5270,7 @@
pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
for (; addr != end; pte++, addr += PAGE_SIZE)
- if (is_target_pte_for_mc(vma, addr, *pte, NULL))
+ if (get_mctgt_type(vma, addr, *pte, NULL))
mc.precharge++; /* increment precharge temporarily */
pte_unmap_unlock(pte - 1, ptl);
cond_resched();
@@ -5442,8 +5442,7 @@
if (!mc.precharge)
break;
- type = is_target_pte_for_mc(vma, addr, ptent, &target);
- switch (type) {
+ switch (get_mctgt_type(vma, addr, ptent, &target)) {
case MC_TARGET_PAGE:
page = target.page;
if (isolate_lru_page(page))
@@ -5456,7 +5455,7 @@
mc.moved_charge++;
}
putback_lru_page(page);
-put: /* is_target_pte_for_mc() gets the page */
+put: /* get_mctgt_type() gets the page */
put_page(page);
break;
case MC_TARGET_SWAP: