[PATCH v2 2/4] (CMA_AGGRESSIVE) Add new function shrink_all_memory_for_cma

[Hui Zhu <zhuhui@xiaomi.com>]

Update this patch according to the comments from Rafael.

Function shrink_all_memory_for_cma try to free `nr_to_reclaim' of memory.
CMA aggressive shrink function will call this functon to free `nr_to_reclaim' of
memory.

Signed-off-by: Hui Zhu <zhuhui@xiaomi.com>
---
 mm/vmscan.c | 58 +++++++++++++++++++++++++++++++++++++++++++---------------
 1 file changed, 43 insertions(+), 15 deletions(-)

diff --git a/mm/vmscan.c b/mm/vmscan.c
index dcb4707..658dc8d 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -3404,6 +3404,28 @@ void wakeup_kswapd(struct zone *zone, int order, enum zone_type classzone_idx)
 	wake_up_interruptible(&pgdat->kswapd_wait);
 }
 
+#if defined CONFIG_HIBERNATION || defined CONFIG_CMA_AGGRESSIVE
+static unsigned long __shrink_all_memory(struct scan_control *sc)
+{
+	struct reclaim_state reclaim_state;
+	struct zonelist *zonelist = node_zonelist(numa_node_id(), sc->gfp_mask);
+	struct task_struct *p = current;
+	unsigned long nr_reclaimed;
+
+	p->flags |= PF_MEMALLOC;
+	lockdep_set_current_reclaim_state(sc->gfp_mask);
+	reclaim_state.reclaimed_slab = 0;
+	p->reclaim_state = &reclaim_state;
+
+	nr_reclaimed = do_try_to_free_pages(zonelist, sc);
+
+	p->reclaim_state = NULL;
+	lockdep_clear_current_reclaim_state();
+	p->flags &= ~PF_MEMALLOC;
+
+	return nr_reclaimed;
+}
+
 #ifdef CONFIG_HIBERNATION
 /*
  * Try to free `nr_to_reclaim' of memory, system-wide, and return the number of
@@ -3415,7 +3437,6 @@ void wakeup_kswapd(struct zone *zone, int order, enum zone_type classzone_idx)
  */
 unsigned long shrink_all_memory(unsigned long nr_to_reclaim)
 {
-	struct reclaim_state reclaim_state;
 	struct scan_control sc = {
 		.nr_to_reclaim = nr_to_reclaim,
 		.gfp_mask = GFP_HIGHUSER_MOVABLE,
@@ -3425,24 +3446,31 @@ unsigned long shrink_all_memory(unsigned long nr_to_reclaim)
 		.may_swap = 1,
 		.hibernation_mode = 1,
 	};
-	struct zonelist *zonelist = node_zonelist(numa_node_id(), sc.gfp_mask);
-	struct task_struct *p = current;
-	unsigned long nr_reclaimed;
-
-	p->flags |= PF_MEMALLOC;
-	lockdep_set_current_reclaim_state(sc.gfp_mask);
-	reclaim_state.reclaimed_slab = 0;
-	p->reclaim_state = &reclaim_state;
 
-	nr_reclaimed = do_try_to_free_pages(zonelist, &sc);
+	return __shrink_all_memory(&sc);
+}
+#endif /* CONFIG_HIBERNATION */
 
-	p->reclaim_state = NULL;
-	lockdep_clear_current_reclaim_state();
-	p->flags &= ~PF_MEMALLOC;
+#ifdef CONFIG_CMA_AGGRESSIVE
+/*
+ * Try to free `nr_to_reclaim' of memory, system-wide, for CMA aggressive
+ * shrink function.
+ */
+void shrink_all_memory_for_cma(unsigned long nr_to_reclaim)
+{
+	struct scan_control sc = {
+		.nr_to_reclaim = nr_to_reclaim,
+		.gfp_mask = GFP_USER | __GFP_MOVABLE | __GFP_HIGHMEM,
+		.priority = DEF_PRIORITY,
+		.may_writepage = !laptop_mode,
+		.may_unmap = 1,
+		.may_swap = 1,
+	};
 
-	return nr_reclaimed;
+	__shrink_all_memory(&sc);
 }
-#endif /* CONFIG_HIBERNATION */
+#endif /* CONFIG_CMA_AGGRESSIVE */
+#endif /* CONFIG_HIBERNATION || CONFIG_CMA_AGGRESSIVE */
 
 /* It's optimal to keep kswapds on the same CPUs as their memory, but
    not required for correctness.  So if the last cpu in a node goes
-- 
1.9.1