[PATCH 1/5] drm/ttm: add max_swap_mem in ttm_mem_global

[Roger He <Hongbo.He@xxxxxxx>]

set its initial value as 1/2 * free swap cache size when module initial.
and adjust this value when allocate TTM memory

Signed-off-by: Roger He <Hongbo.He@xxxxxxx>
---
 drivers/gpu/drm/ttm/ttm_memory.c | 10 ++++++++--
 include/drm/ttm/ttm_memory.h     |  2 ++
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/ttm/ttm_memory.c b/drivers/gpu/drm/ttm/ttm_memory.c
index aa0c381..b48931d 100644
--- a/drivers/gpu/drm/ttm/ttm_memory.c
+++ b/drivers/gpu/drm/ttm/ttm_memory.c
@@ -36,6 +36,7 @@
 #include <linux/mm.h>
 #include <linux/module.h>
 #include <linux/slab.h>
+#include <linux/swap.h>
 
 #define TTM_MEMORY_ALLOC_RETRIES 4
 
@@ -372,9 +373,9 @@ int ttm_mem_global_init(struct ttm_mem_global *glob)
 		kobject_put(&glob->kobj);
 		return ret;
 	}
-
+	/* set it as 1/2 * swap free space we can get at that time */
+	glob->max_swap_mem = get_nr_swap_pages() << (PAGE_SHIFT - 1);
 	si_meminfo(&si);
-
 	ret = ttm_mem_init_kernel_zone(glob, &si);
 	if (unlikely(ret != 0))
 		goto out_no_zone;
@@ -473,12 +474,17 @@ static int ttm_mem_global_reserve(struct ttm_mem_global *glob,
 				  struct ttm_mem_zone *single_zone,
 				  uint64_t amount, bool reserve)
 {
+	uint64_t free_swap_mem = get_nr_swap_pages() << (PAGE_SHIFT - 1);
 	uint64_t limit;
 	int ret = -ENOMEM;
 	unsigned int i;
 	struct ttm_mem_zone *zone;
 
 	spin_lock(&glob->lock);
+	/* adjust the max_swap_mem to cover the new inserted swap space */
+	if (glob->max_swap_mem < free_swap_mem)
+		glob->max_swap_mem = free_swap_mem;
+
 	for (i = 0; i < glob->num_zones; ++i) {
 		zone = glob->zones[i];
 		if (single_zone && zone != single_zone)
diff --git a/include/drm/ttm/ttm_memory.h b/include/drm/ttm/ttm_memory.h
index 8936285..ad5a557 100644
--- a/include/drm/ttm/ttm_memory.h
+++ b/include/drm/ttm/ttm_memory.h
@@ -49,6 +49,7 @@
  * @work: The workqueue callback for the shrink queue.
  * @lock: Lock to protect the @shrink - and the memory accounting members,
  * that is, essentially the whole structure with some exceptions.
+ * @max_swap_mem: upper limit of swap space TTM can use
  * @zones: Array of pointers to accounting zones.
  * @num_zones: Number of populated entries in the @zones array.
  * @zone_kernel: Pointer to the kernel zone.
@@ -67,6 +68,7 @@ struct ttm_mem_global {
 	struct workqueue_struct *swap_queue;
 	struct work_struct work;
 	spinlock_t lock;
+	uint64_t max_swap_mem;
 	struct ttm_mem_zone *zones[TTM_MEM_MAX_ZONES];
 	unsigned int num_zones;
 	struct ttm_mem_zone *zone_kernel;
-- 
2.7.4

_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/dri-devel