Piteball
/
android_kernel_google_msm
mirror of https://github.com/followmsi/android_kernel_google_msm.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

mmc: use percentage changed sectors as indication to check BKOPS need 

In order to keep card endurance, it is best not to check the need for
BKOPS every time the MMC is idle.
However, the decision when to check the card need for BKOPS according
to number of changed sectors doesn't fit all cards sizes. Therefore,
the check for BKOPS need is based on percentages of changed sectors
of the card size.
In order to assure that BKOPS will be triggered again in case it was
interrupted, the accumulated number of changed sectors is cleared only
in case BKOPS was completed without interruption.

Change-Id: I598f64b652a524a431b87d103fd5890b808f11b1
Signed-off-by: Maya Erez <merez@codeaurora.org>
(cherry picked from commit e1eae988976536834759a45cf7f62e1cb2b82838)
This commit is contained in:
Maya Erez 2013-01-16 09:48:25 +02:00 committed by Iliyan Malchev
parent 888a37eb3b
commit 2ea2bfc703
5 changed files with 63 additions and 41 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
Documentation/mmc/mmc-dev-attrs.txt
View File

@ -25,14 +25,14 @@ The following attributes are read/write.
running parallel lmdd write and lmdd read operations and calculating
the max number of packed writes requests.
min_sectors_to_check_bkops_status This attribute is used to
determine whether the status bit that indicates the need for BKOPS
should be checked. The value is stored in this attribute represents
the minimum number of sectors that needs to be changed in the device
(written or discarded) in order to require the status-bit of BKOPS
to be checked. The value can modified via sysfs by writing the
required value to:
/sys/block/<block_dev_name>/min_sectors_to_check_bkops_status
bkops_check_threshold This attribute is used to determine whether
the status bit that indicates the need for BKOPS should be checked.
The value should be given in percentages of the card size.
This value is used to calculate the minimum number of sectors that
needs to be changed in the device (written or discarded) in order to
require the status-bit of BKOPS to be checked.
The value can modified via sysfs by writing the required value to:
/sys/block/<block_dev_name>/bkops_check_threshold
SD and MMC Device Attributes
============================

72
drivers/mmc/card/block.c
View File

@ -121,7 +121,7 @@ struct mmc_blk_data {
struct device_attribute force_ro;
struct device_attribute power_ro_lock;
struct device_attribute num_wr_reqs_to_start_packing;
struct device_attribute min_sectors_to_check_bkops_status;
struct device_attribute bkops_check_threshold;
int area_type;
};
@ -308,43 +308,60 @@ num_wr_reqs_to_start_packing_store(struct device *dev,
}
static ssize_t
min_sectors_to_check_bkops_status_show(struct device *dev,
bkops_check_threshold_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct mmc_blk_data *md = mmc_blk_get(dev_to_disk(dev));
unsigned int min_sectors_to_check_bkops_status;
struct mmc_card *card = md->queue.card;
int ret;
if (!card)
return -EINVAL;
min_sectors_to_check_bkops_status =
card->bkops_info.min_sectors_to_queue_delayed_work;
ret = snprintf(buf, PAGE_SIZE, "%d\n",
min_sectors_to_check_bkops_status);
ret = -EINVAL;
else
ret = snprintf(buf, PAGE_SIZE, "%d\n",
card->bkops_info.size_percentage_to_queue_delayed_work);
mmc_blk_put(md);
return ret;
}
static ssize_t
min_sectors_to_check_bkops_status_store(struct device *dev,
bkops_check_threshold_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
int value;
struct mmc_blk_data *md = mmc_blk_get(dev_to_disk(dev));
struct mmc_card *card = md->queue.card;
unsigned int card_size;
int ret = count;
if (!card)
return -EINVAL;
if (!card) {
ret = -EINVAL;
goto exit;
}
sscanf(buf, "%d", &value);
if (value >= 0)
card->bkops_info.min_sectors_to_queue_delayed_work = value;
if ((value <= 0) || (value >= 100)) {
ret = -EINVAL;
goto exit;
}
card_size = (unsigned int)get_capacity(md->disk);
if (card_size <= 0) {
ret = -EINVAL;
goto exit;
}
card->bkops_info.size_percentage_to_queue_delayed_work = value;
card->bkops_info.min_sectors_to_queue_delayed_work =
(card_size * value) / 100;
pr_debug("%s: size_percentage = %d, min_sectors = %d",
mmc_hostname(card->host),
card->bkops_info.size_percentage_to_queue_delayed_work,
card->bkops_info.min_sectors_to_queue_delayed_work);
exit:
mmc_blk_put(md);
return count;
}
@ -2093,6 +2110,8 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card,
{
struct mmc_blk_data *md;
int devidx, ret;
unsigned int percentage =
BKOPS_SIZE_PERCENTAGE_TO_QUEUE_DELAYED_WORK;
devidx = find_first_zero_bit(dev_use, max_devices);
if (devidx >= max_devices)
@ -2170,6 +2189,10 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card,
blk_queue_logical_block_size(md->queue.queue, 512);
set_capacity(md->disk, size);
card->bkops_info.size_percentage_to_queue_delayed_work = percentage;
card->bkops_info.min_sectors_to_queue_delayed_work =
((unsigned int)size * percentage) / 100;
if (mmc_host_cmd23(card->host)) {
if (mmc_card_mmc(card) ||
(mmc_card_sd(card) &&
@ -2362,22 +2385,19 @@ static int mmc_add_disk(struct mmc_blk_data *md)
if (ret)
goto num_wr_reqs_to_start_packing_fail;
md->min_sectors_to_check_bkops_status.show =
min_sectors_to_check_bkops_status_show;
md->min_sectors_to_check_bkops_status.store =
min_sectors_to_check_bkops_status_store;
sysfs_attr_init(&md->min_sectors_to_check_bkops_status.attr);
md->min_sectors_to_check_bkops_status.attr.name =
"min_sectors_to_check_bkops_status";
md->min_sectors_to_check_bkops_status.attr.mode = S_IRUGO | S_IWUSR;
md->bkops_check_threshold.show = bkops_check_threshold_show;
md->bkops_check_threshold.store = bkops_check_threshold_store;
sysfs_attr_init(&md->bkops_check_threshold.attr);
md->bkops_check_threshold.attr.name = "bkops_check_threshold";
md->bkops_check_threshold.attr.mode = S_IRUGO | S_IWUSR;
ret = device_create_file(disk_to_dev(md->disk),
&md->min_sectors_to_check_bkops_status);
&md->bkops_check_threshold);
if (ret)
goto min_sectors_to_check_bkops_status_fails;
goto bkops_check_threshold_fails;
return ret;
min_sectors_to_check_bkops_status_fails:
bkops_check_threshold_fails:
device_remove_file(disk_to_dev(md->disk),
&md->num_wr_reqs_to_start_packing);
num_wr_reqs_to_start_packing_fail:

3
drivers/mmc/core/core.c
View File

@ -297,8 +297,6 @@ void mmc_start_delayed_bkops(struct mmc_card *card)
pr_debug("%s: %s: queueing delayed_bkops_work\n",
mmc_hostname(card->host), __func__);
card->bkops_info.sectors_changed = 0;
/*
* cancel_delayed_bkops_work will prevent a race condition between
* fetching a request by the mmcqd and the delayed work, in case
@ -448,6 +446,7 @@ void mmc_bkops_completion_polling(struct work_struct *work)
pr_debug("%s: %s: completed BKOPs, exit polling\n",
mmc_hostname(card->host), __func__);
mmc_card_clr_doing_bkops(card);
card->bkops_info.sectors_changed = 0;
goto out;
}

3
drivers/mmc/core/mmc.c
View File

@ -1334,9 +1334,6 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
if (card->bkops_info.host_delay_ms)
card->bkops_info.delay_ms =
card->bkops_info.host_delay_ms;
card->bkops_info.min_sectors_to_queue_delayed_work =
BKOPS_MIN_SECTORS_TO_QUEUE_DELAYED_WORK;
}
}

10
include/linux/mmc/card.h
View File

@ -236,6 +236,12 @@ struct mmc_part {
* @host_delay_ms: The host controller time to start bkops
* @delay_ms: The time to start the BKOPS
* delayed work once MMC thread is idle
* @min_sectors_to_queue_delayed_work: the changed
* number of sectors that should issue check for BKOPS
* need
* @size_percentage_to_queue_delayed_work: the changed
* percentage of sectors that should issue check for
* BKOPS need
* @poll_for_completion: Poll on BKOPS completion
* @cancel_delayed_work: A flag to indicate if the delayed work
* should be cancelled
@ -247,6 +253,7 @@ struct mmc_bkops_info {
unsigned int host_delay_ms;
unsigned int delay_ms;
unsigned int min_sectors_to_queue_delayed_work;
unsigned int size_percentage_to_queue_delayed_work;
/*
* A default time for checking the need for non urgent BKOPS once mmcqd
* is idle.
@ -264,9 +271,8 @@ struct mmc_bkops_info {
* mmcqd thread is idle.
* The delayed work for idle BKOPS will be scheduled only after a significant
* amount of write or discard data.
* 100MB is chosen based on benchmark tests.
*/
#define BKOPS_MIN_SECTORS_TO_QUEUE_DELAYED_WORK 204800 /* 100MB */
#define BKOPS_SIZE_PERCENTAGE_TO_QUEUE_DELAYED_WORK 1 /* 1% */
};
/*