]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commit
mmc: fix async request mechanism for sequential read scenarios
authorKonstantin Dorfman <kdorfman@codeaurora.org>
Mon, 14 Jan 2013 19:28:17 +0000 (14:28 -0500)
committerChris Ball <cjb@laptop.org>
Mon, 11 Feb 2013 18:28:49 +0000 (13:28 -0500)
commit2220eedfd7aea69008173a224975e10284fbe854
tree71906c2638d2e0052b15a40e71310f6984f3ee8f
parent369d321ed1baa7748e770aaaae4d8effad699633
mmc: fix async request mechanism for sequential read scenarios

When current request is running on the bus and if next request fetched
by mmcqd is NULL, mmc context (mmcqd thread) gets blocked until the
current request completes. This means that if new request comes in while
the mmcqd thread is blocked, this new request can not be prepared in
parallel to current ongoing request. This may result in delaying the new
request execution and increase it's latency.

This change allows to wake up the MMC thread on new request arrival.
Now once the MMC thread is woken up, a new request can be fetched and
prepared in parallel to the current running request which means this new
request can be started immediately after the current running request
completes.

With this change read throughput is improved by 16%.

Signed-off-by: Konstantin Dorfman <kdorfman@codeaurora.org>
Reviewed-by: Seungwon Jeon <tgih.jun@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
drivers/mmc/card/block.c
drivers/mmc/card/queue.c
drivers/mmc/card/queue.h
drivers/mmc/core/bus.c
drivers/mmc/core/core.c
drivers/mmc/core/core.h
include/linux/mmc/card.h
include/linux/mmc/core.h
include/linux/mmc/host.h