Commit b9947297 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

block: refactor disk_update_readahead 



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: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarKeith Busch <kbusch@kernel.org>
Reviewed-by: default avatarChaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: default avatarMing Lei <ming.lei@redhat.com>
Reviewed-by: default avatarDamien Le Moal <dlemoal@kernel.org>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240213073425.1621680-3-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 8c4955c0

block/blk-settings.c

+12 −9
Original line number Diff line number Diff line
@@ -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_SECTORS_SHIFT;

}



/**

 * 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);