diff mbox series

[02/14] block: refactor disk_update_readahead

Message ID 20240128165813.3213508-3-hch@lst.de (mailing list archive)
State New, archived
Headers show
Series [01/14] block: move max_{open,active}_zones to struct queue_limits | expand

Commit Message

Christoph Hellwig Jan. 28, 2024, 4:58 p.m. UTC 
Factor out a blk_apply_bdi_limits limits helper that can be used with
an explicit queue_limits argument, which will be useful later.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
---
 block/blk-settings.c | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

Comments

Bart Van Assche Jan. 29, 2024, 2:59 a.m. UTC | #1 
On 1/28/24 08:58, Christoph Hellwig wrote:
> +static void blk_apply_bdi_limits(struct backing_dev_info *bdi,
> +		struct queue_limits *lim)
> +{
> +	/*
> +	 * For read-ahead of large files to be effective, we need to read ahead
> +	 * at least twice the optimal I/O size.
> +	 */
> +	bdi->ra_pages = max(lim->io_opt * 2 / PAGE_SIZE, VM_READAHEAD_PAGES);
> +	bdi->io_pages = lim->max_sectors >> (PAGE_SHIFT - 9);
> +}

Would this be a good opportunity to change (PAGE_SHIFT - 9) into PAGE_SECTORS_SHIFT?

Thanks,

Bart.
Christoph Hellwig Jan. 29, 2024, 6:16 a.m. UTC | #2 
On Sun, Jan 28, 2024 at 06:59:31PM -0800, Bart Van Assche wrote:
>> +	/*
>> +	 * For read-ahead of large files to be effective, we need to read ahead
>> +	 * at least twice the optimal I/O size.
>> +	 */
>> +	bdi->ra_pages = max(lim->io_opt * 2 / PAGE_SIZE, VM_READAHEAD_PAGES);
>> +	bdi->io_pages = lim->max_sectors >> (PAGE_SHIFT - 9);
>> +}
>
> Would this be a good opportunity to change (PAGE_SHIFT - 9) into
> PAGE_SECTORS_SHIFT?

If I have to respin for some reason I'll include it.  Otherwise feel
free to send a trivial follow on patch.
diff mbox series

Patch

diff --git a/block/blk-settings.c b/block/blk-settings.c
index 06ea91e51b8b2e..e872b0e168525e 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -85,6 +85,17 @@  void blk_set_stacking_limits(struct queue_limits *lim)
 }
 EXPORT_SYMBOL(blk_set_stacking_limits);
 
+static void blk_apply_bdi_limits(struct backing_dev_info *bdi,
+		struct queue_limits *lim)
+{
+	/*
+	 * For read-ahead of large files to be effective, we need to read ahead
+	 * at least twice the optimal I/O size.
+	 */
+	bdi->ra_pages = max(lim->io_opt * 2 / PAGE_SIZE, VM_READAHEAD_PAGES);
+	bdi->io_pages = lim->max_sectors >> (PAGE_SHIFT - 9);
+}
+
 /**
  * blk_queue_bounce_limit - set bounce buffer limit for queue
  * @q: the request queue for the device
@@ -393,15 +404,7 @@  EXPORT_SYMBOL(blk_queue_alignment_offset);
 
 void disk_update_readahead(struct gendisk *disk)
 {
-	struct request_queue *q = disk->queue;
-
-	/*
-	 * For read-ahead of large files to be effective, we need to read ahead
-	 * at least twice the optimal I/O size.
-	 */
-	disk->bdi->ra_pages =
-		max(queue_io_opt(q) * 2 / PAGE_SIZE, VM_READAHEAD_PAGES);
-	disk->bdi->io_pages = queue_max_sectors(q) >> (PAGE_SHIFT - 9);
+	blk_apply_bdi_limits(disk->bdi, &disk->queue->limits);
 }
 EXPORT_SYMBOL_GPL(disk_update_readahead);