[PATCHv2 1/3] zram: introduce ZRAM_PP_SLOT flag

[Sergey Senozhatsky]

This flag will indicate that the slot was selected as
a candidate slot for post-processing (pp) and was assigned
to a pp bucket.

Signed-off-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
---
 drivers/block/zram/zram_drv.c | 10 ++++++++--
 drivers/block/zram/zram_drv.h |  1 +
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 1f1bf175a6c3..a14aef6bf634 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -178,6 +178,7 @@ static inline u32 zram_get_priority(struct zram *zram, u32 index)
 static void zram_accessed(struct zram *zram, u32 index)
 {
 	zram_clear_flag(zram, index, ZRAM_IDLE);
+	zram_clear_flag(zram, index, ZRAM_PP_SLOT);
 #ifdef CONFIG_ZRAM_TRACK_ENTRY_ACTIME
 	zram->table[index].ac_time = ktime_get_boottime();
 #endif
@@ -659,8 +660,9 @@ static ssize_t writeback_store(struct device *dev,
 			goto next;
 
 		if (zram_test_flag(zram, index, ZRAM_WB) ||
-				zram_test_flag(zram, index, ZRAM_SAME) ||
-				zram_test_flag(zram, index, ZRAM_UNDER_WB))
+		    zram_test_flag(zram, index, ZRAM_SAME) ||
+		    zram_test_flag(zram, index, ZRAM_PP_SLOT) ||
+		    zram_test_flag(zram, index, ZRAM_UNDER_WB))
 			goto next;
 
 		if (mode & IDLE_WRITEBACK &&
@@ -1368,6 +1370,9 @@ static void zram_free_page(struct zram *zram, size_t index)
 		goto out;
 	}
 
+	if (zram_test_flag(zram, index, ZRAM_PP_SLOT))
+		zram_clear_flag(zram, index, ZRAM_PP_SLOT);
+
 	handle = zram_get_handle(zram, index);
 	if (!handle)
 		return;
@@ -1927,6 +1932,7 @@ static ssize_t recompress_store(struct device *dev,
 		if (zram_test_flag(zram, index, ZRAM_WB) ||
 		    zram_test_flag(zram, index, ZRAM_UNDER_WB) ||
 		    zram_test_flag(zram, index, ZRAM_SAME) ||
+		    zram_test_flag(zram, index, ZRAM_PP_SLOT) ||
 		    zram_test_flag(zram, index, ZRAM_INCOMPRESSIBLE))
 			goto next;
 
diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h
index b976824ead67..e0578b3542ce 100644
--- a/drivers/block/zram/zram_drv.h
+++ b/drivers/block/zram/zram_drv.h
@@ -50,6 +50,7 @@ enum zram_pageflags {
 	ZRAM_SAME,	/* Page consists the same element */
 	ZRAM_WB,	/* page is stored on backing_device */
 	ZRAM_UNDER_WB,	/* page is under writeback */
+	ZRAM_PP_SLOT,	/* Selected for post-processing */
 	ZRAM_HUGE,	/* Incompressible page */
 	ZRAM_IDLE,	/* not accessed page since last idle marking */
 	ZRAM_INCOMPRESSIBLE, /* none of the algorithms could compress it */
-- 
2.46.0.469.g59c65b2a67-goog