Revision 5ea47691bd99e1100707ec63364aff72324e2af4 authored by Daniel Drake on 20 March 2019, 06:36:53 UTC, committed by Ulf Hansson on 21 March 2019, 10:19:06 UTC
Setting max_blk_count to 1 here was causing the mmc block layer
to always use the MMC_READ_SINGLE_BLOCK command here, which the
driver does not DMA-accelerate.
Drop the max_blk_ settings here. The mmc host defaults suffice,
along with the max_segs and max_seg_size settings, which I have
now documented in more detail.
Now each MMC command reads 4 512-byte blocks, using DMA instead of
PIO. On my SD card, this increases read performance (measured with dd)
from 167kb/sec to 4.6mb/sec.
Link: http://lkml.kernel.org/r/CAD8Lp47L5T3jnAjBiPs1cQ+yFA3L6LJtgFvMETnBrY63-Zdi2g@mail.gmail.com
Signed-off-by: Daniel Drake <drake@endlessm.com>
Reviewed-by: Oleksij Rempel <linux@rempel-privat.de>
Fixes: c5413ad815a6 ("mmc: add new Alcor Micro Cardreader SD/MMC driver")
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
1 parent 031d2cc
Makefile
# SPDX-License-Identifier: GPL-2.0
#
# Makefile for the Linux JFS filesystem routines.
#
obj-$(CONFIG_JFS_FS) += jfs.o
jfs-y := super.o file.o inode.o namei.o jfs_mount.o jfs_umount.o \
jfs_xtree.o jfs_imap.o jfs_debug.o jfs_dmap.o \
jfs_unicode.o jfs_dtree.o jfs_inode.o jfs_discard.o \
jfs_extent.o symlink.o jfs_metapage.o \
jfs_logmgr.o jfs_txnmgr.o jfs_uniupr.o \
resize.o xattr.o ioctl.o
jfs-$(CONFIG_JFS_POSIX_ACL) += acl.o
ccflags-y := -D_JFS_4K
Computing file changes ...
