mm/page-writeback.c: Update comment for BANDWIDTH_INTERVAL

The name of the BANDWIDTH_INTERVAL macro is misleading, as it is not
only used in the bandwidth update functions wb_update_bandwidth() and
__wb_update_bandwidth(), but also in the dirty limit update function
domain_update_dirty_limit().

Currently, we haven't found an ideal name, so update the comment only.

Signed-off-by: Tang Yizhou <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Christian Brauner <[email protected]>

Author: Tang Yizhou

mm/page-writeback.c

@@ -54,7 +54,7 @@
 #define DIRTY_POLL_THRESH	(128 >> (PAGE_SHIFT - 10))
 
 /*
- * Estimate write bandwidth at 200ms intervals.
+ * Estimate write bandwidth or update dirty limit at 200ms intervals.
  */
 #define BANDWIDTH_INTERVAL	max(HZ/5, 1)