On Thu, 2023-08-24 at 12:55 +0200, Ulf Hansson wrote: > > External email : Please do not click links or open attachments until > you have verified the sender or the content. > On Fri, 18 Aug 2023 at 04:45, <Sharp.Xia@xxxxxxxxxxxx> wrote: > > > > From: Sharp Xia <Sharp.Xia@xxxxxxxxxxxx> > > > > MMC does not set readahead and uses the default VM_READAHEAD_PAGES > > resulting in slower reading speed. > > Use the max_req_size reported by host driver to set the optimal > > I/O size to improve performance. > > This seems reasonable to me. However, it would be nice if you could > share some performance numbers too - comparing before and after > $subject patch. > > Kind regards > Uffe > > > > > Signed-off-by: Sharp Xia <Sharp.Xia@xxxxxxxxxxxx> > > --- > > drivers/mmc/core/queue.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c > > index b396e3900717..fc83c4917360 100644 > > --- a/drivers/mmc/core/queue.c > > +++ b/drivers/mmc/core/queue.c > > @@ -359,6 +359,7 @@ static void mmc_setup_queue(struct mmc_queue > *mq, struct mmc_card *card) > > blk_queue_bounce_limit(mq->queue, BLK_BOUNCE_HIGH); > > blk_queue_max_hw_sectors(mq->queue, > > min(host->max_blk_count, host->max_req_size / > 512)); > > + blk_queue_io_opt(mq->queue, host->max_req_size); > > if (host->can_dma_map_merge) > > WARN(!blk_queue_can_use_dma_map_merging(mq->queue, > > mmc_dev(hos > t)), > > -- > > 2.18.0 > > I test this patch on internal platform(kernel-5.15). Before: console:/ # echo 3 > /proc/sys/vm/drop_caches console:/ # dd if=/mnt/media_rw/8031-130D/super.img of=/dev/null 4485393+1 records in 4485393+1 records out 2296521564 bytes (2.1 G) copied, 37.124446 s, 59 M/s console:/ # cat /sys/block/mmcblk0/queue/read_ahead_kb 128 After: console:/ # echo 3 > /proc/sys/vm/drop_caches console:/ # dd if=/mnt/media_rw/8031-130D/super.img of=/dev/null 4485393+1 records in 4485393+1 records out 2296521564 bytes (2.1 G) copied, 28.956049 s, 76 M/s console:/ # cat /sys/block/mmcblk0/queue/read_ahead_kb 1024
