From: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
Add a new function writeback_prep_or_skip_index() that does the check
and set the approapriate flags before writeback starts. The function
returns false if the index can be skipped.
Signed-off-by: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
---
drivers/block/zram/zram_drv.c | 68 +++++++++++++++++++++--------------
1 file changed, 42 insertions(+), 26 deletions(-)
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 06673c6ca255..eaf9e227778e 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -595,6 +595,46 @@ static void read_from_bdev_async(struct zram *zram, struct page *page,
#define IDLE_WRITEBACK (1<<1)
#define INCOMPRESSIBLE_WRITEBACK (1<<2)
+/*
+ * Returns: true if the index was prepared for further processing
+ * false if the index can be skipped
+ */
+static bool writeback_prep_or_skip_index(struct zram *zram, int mode,
+ unsigned long index)
+{
+ bool ret = false;
+
+ zram_slot_lock(zram, index);
+ if (!zram_allocated(zram, index))
+ goto skip;
+
+ if (zram_test_flag(zram, index, ZRAM_WB) ||
+ zram_test_flag(zram, index, ZRAM_SAME) ||
+ zram_test_flag(zram, index, ZRAM_UNDER_WB))
+ goto skip;
+
+ if (mode & IDLE_WRITEBACK && !zram_test_flag(zram, index, ZRAM_IDLE))
+ goto skip;
+ if (mode & HUGE_WRITEBACK && !zram_test_flag(zram, index, ZRAM_HUGE))
+ goto skip;
+ if (mode & INCOMPRESSIBLE_WRITEBACK &&
+ !zram_test_flag(zram, index, ZRAM_INCOMPRESSIBLE))
+ goto skip;
+
+ /*
+ * Clearing ZRAM_UNDER_WB is duty of caller.
+ * IOW, zram_free_page never clear it.
+ */
+ zram_set_flag(zram, index, ZRAM_UNDER_WB);
+ /* Need for hugepage writeback racing */
+ zram_set_flag(zram, index, ZRAM_IDLE);
+
+ ret = true;
+skip:
+ zram_slot_unlock(zram, index);
+ return ret;
+}
+
static ssize_t writeback_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t len)
{
@@ -662,33 +702,9 @@ static ssize_t writeback_store(struct device *dev,
}
}
- zram_slot_lock(zram, index);
- if (!zram_allocated(zram, index))
- goto next;
+ if (!writeback_prep_or_skip_index(zram, mode, index))
+ continue;
- if (zram_test_flag(zram, index, ZRAM_WB) ||
- zram_test_flag(zram, index, ZRAM_SAME) ||
- zram_test_flag(zram, index, ZRAM_UNDER_WB))
- goto next;
-
- if (mode & IDLE_WRITEBACK &&
- !zram_test_flag(zram, index, ZRAM_IDLE))
- goto next;
- if (mode & HUGE_WRITEBACK &&
- !zram_test_flag(zram, index, ZRAM_HUGE))
- goto next;
- if (mode & INCOMPRESSIBLE_WRITEBACK &&
- !zram_test_flag(zram, index, ZRAM_INCOMPRESSIBLE))
- goto next;
-
- /*
- * Clearing ZRAM_UNDER_WB is duty of caller.
- * IOW, zram_free_page never clear it.
- */
- zram_set_flag(zram, index, ZRAM_UNDER_WB);
- /* Need for hugepage writeback racing */
- zram_set_flag(zram, index, ZRAM_IDLE);
- zram_slot_unlock(zram, index);
if (zram_read_page(zram, page, index, NULL)) {
zram_slot_lock(zram, index);
zram_clear_flag(zram, index, ZRAM_UNDER_WB);
--
2.40.1
