Merge branch 'master' into for-2.6.35
Conflicts:
fs/block_dev.c
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/Documentation/cgroups/blkio-controller.txt b/Documentation/cgroups/blkio-controller.txt
index 630879c..48e0b21 100644
--- a/Documentation/cgroups/blkio-controller.txt
+++ b/Documentation/cgroups/blkio-controller.txt
@@ -17,6 +17,9 @@
You can do a very simple testing of running two dd threads in two different
cgroups. Here is what you can do.
+- Enable Block IO controller
+ CONFIG_BLK_CGROUP=y
+
- Enable group scheduling in CFQ
CONFIG_CFQ_GROUP_IOSCHED=y
@@ -54,32 +57,52 @@
Various user visible config options
===================================
+CONFIG_BLK_CGROUP
+ - Block IO controller.
+
+CONFIG_DEBUG_BLK_CGROUP
+ - Debug help. Right now some additional stats file show up in cgroup
+ if this option is enabled.
+
CONFIG_CFQ_GROUP_IOSCHED
- Enables group scheduling in CFQ. Currently only 1 level of group
creation is allowed.
-CONFIG_DEBUG_CFQ_IOSCHED
- - Enables some debugging messages in blktrace. Also creates extra
- cgroup file blkio.dequeue.
-
-Config options selected automatically
-=====================================
-These config options are not user visible and are selected/deselected
-automatically based on IO scheduler configuration.
-
-CONFIG_BLK_CGROUP
- - Block IO controller. Selected by CONFIG_CFQ_GROUP_IOSCHED.
-
-CONFIG_DEBUG_BLK_CGROUP
- - Debug help. Selected by CONFIG_DEBUG_CFQ_IOSCHED.
-
Details of cgroup files
=======================
- blkio.weight
- - Specifies per cgroup weight.
-
+ - Specifies per cgroup weight. This is default weight of the group
+ on all the devices until and unless overridden by per device rule.
+ (See blkio.weight_device).
Currently allowed range of weights is from 100 to 1000.
+- blkio.weight_device
+ - One can specify per cgroup per device rules using this interface.
+ These rules override the default value of group weight as specified
+ by blkio.weight.
+
+ Following is the format.
+
+ #echo dev_maj:dev_minor weight > /path/to/cgroup/blkio.weight_device
+ Configure weight=300 on /dev/sdb (8:16) in this cgroup
+ # echo 8:16 300 > blkio.weight_device
+ # cat blkio.weight_device
+ dev weight
+ 8:16 300
+
+ Configure weight=500 on /dev/sda (8:0) in this cgroup
+ # echo 8:0 500 > blkio.weight_device
+ # cat blkio.weight_device
+ dev weight
+ 8:0 500
+ 8:16 300
+
+ Remove specific weight for /dev/sda in this cgroup
+ # echo 8:0 0 > blkio.weight_device
+ # cat blkio.weight_device
+ dev weight
+ 8:16 300
+
- blkio.time
- disk time allocated to cgroup per device in milliseconds. First
two fields specify the major and minor number of the device and
@@ -92,13 +115,105 @@
third field specifies the number of sectors transferred by the
group to/from the device.
+- blkio.io_service_bytes
+ - Number of bytes transferred to/from the disk by the group. These
+ are further divided by the type of operation - read or write, sync
+ or async. First two fields specify the major and minor number of the
+ device, third field specifies the operation type and the fourth field
+ specifies the number of bytes.
+
+- blkio.io_serviced
+ - Number of IOs completed to/from the disk by the group. These
+ are further divided by the type of operation - read or write, sync
+ or async. First two fields specify the major and minor number of the
+ device, third field specifies the operation type and the fourth field
+ specifies the number of IOs.
+
+- blkio.io_service_time
+ - Total amount of time between request dispatch and request completion
+ for the IOs done by this cgroup. This is in nanoseconds to make it
+ meaningful for flash devices too. For devices with queue depth of 1,
+ this time represents the actual service time. When queue_depth > 1,
+ that is no longer true as requests may be served out of order. This
+ may cause the service time for a given IO to include the service time
+ of multiple IOs when served out of order which may result in total
+ io_service_time > actual time elapsed. This time is further divided by
+ the type of operation - read or write, sync or async. First two fields
+ specify the major and minor number of the device, third field
+ specifies the operation type and the fourth field specifies the
+ io_service_time in ns.
+
+- blkio.io_wait_time
+ - Total amount of time the IOs for this cgroup spent waiting in the
+ scheduler queues for service. This can be greater than the total time
+ elapsed since it is cumulative io_wait_time for all IOs. It is not a
+ measure of total time the cgroup spent waiting but rather a measure of
+ the wait_time for its individual IOs. For devices with queue_depth > 1
+ this metric does not include the time spent waiting for service once
+ the IO is dispatched to the device but till it actually gets serviced
+ (there might be a time lag here due to re-ordering of requests by the
+ device). This is in nanoseconds to make it meaningful for flash
+ devices too. This time is further divided by the type of operation -
+ read or write, sync or async. First two fields specify the major and
+ minor number of the device, third field specifies the operation type
+ and the fourth field specifies the io_wait_time in ns.
+
+- blkio.io_merged
+ - Total number of bios/requests merged into requests belonging to this
+ cgroup. This is further divided by the type of operation - read or
+ write, sync or async.
+
+- blkio.io_queued
+ - Total number of requests queued up at any given instant for this
+ cgroup. This is further divided by the type of operation - read or
+ write, sync or async.
+
+- blkio.avg_queue_size
+ - Debugging aid only enabled if CONFIG_DEBUG_BLK_CGROUP=y.
+ The average queue size for this cgroup over the entire time of this
+ cgroup's existence. Queue size samples are taken each time one of the
+ queues of this cgroup gets a timeslice.
+
+- blkio.group_wait_time
+ - Debugging aid only enabled if CONFIG_DEBUG_BLK_CGROUP=y.
+ This is the amount of time the cgroup had to wait since it became busy
+ (i.e., went from 0 to 1 request queued) to get a timeslice for one of
+ its queues. This is different from the io_wait_time which is the
+ cumulative total of the amount of time spent by each IO in that cgroup
+ waiting in the scheduler queue. This is in nanoseconds. If this is
+ read when the cgroup is in a waiting (for timeslice) state, the stat
+ will only report the group_wait_time accumulated till the last time it
+ got a timeslice and will not include the current delta.
+
+- blkio.empty_time
+ - Debugging aid only enabled if CONFIG_DEBUG_BLK_CGROUP=y.
+ This is the amount of time a cgroup spends without any pending
+ requests when not being served, i.e., it does not include any time
+ spent idling for one of the queues of the cgroup. This is in
+ nanoseconds. If this is read when the cgroup is in an empty state,
+ the stat will only report the empty_time accumulated till the last
+ time it had a pending request and will not include the current delta.
+
+- blkio.idle_time
+ - Debugging aid only enabled if CONFIG_DEBUG_BLK_CGROUP=y.
+ This is the amount of time spent by the IO scheduler idling for a
+ given cgroup in anticipation of a better request than the exising ones
+ from other queues/cgroups. This is in nanoseconds. If this is read
+ when the cgroup is in an idling state, the stat will only report the
+ idle_time accumulated till the last idle period and will not include
+ the current delta.
+
- blkio.dequeue
- - Debugging aid only enabled if CONFIG_DEBUG_CFQ_IOSCHED=y. This
+ - Debugging aid only enabled if CONFIG_DEBUG_BLK_CGROUP=y. This
gives the statistics about how many a times a group was dequeued
from service tree of the device. First two fields specify the major
and minor number of the device and third field specifies the number
of times a group was dequeued from a particular device.
+- blkio.reset_stats
+ - Writing an int to this file will result in resetting all the stats
+ for that cgroup.
+
CFQ sysfs tunable
=================
/sys/block/<disk>/queue/iosched/group_isolation
diff --git a/block/Kconfig b/block/Kconfig
index f9e89f4..9be0b56 100644
--- a/block/Kconfig
+++ b/block/Kconfig
@@ -77,29 +77,6 @@
T10/SCSI Data Integrity Field or the T13/ATA External Path
Protection. If in doubt, say N.
-config BLK_CGROUP
- tristate "Block cgroup support"
- depends on CGROUPS
- depends on CFQ_GROUP_IOSCHED
- default n
- ---help---
- Generic block IO controller cgroup interface. This is the common
- cgroup interface which should be used by various IO controlling
- policies.
-
- Currently, CFQ IO scheduler uses it to recognize task groups and
- control disk bandwidth allocation (proportional time slice allocation)
- to such task groups.
-
-config DEBUG_BLK_CGROUP
- bool
- depends on BLK_CGROUP
- default n
- ---help---
- Enable some debugging help. Currently it stores the cgroup path
- in the blk group which can be used by cfq for tracing various
- group related activity.
-
endif # BLOCK
config BLOCK_COMPAT
diff --git a/block/Kconfig.iosched b/block/Kconfig.iosched
index fc71cf07..3199b76 100644
--- a/block/Kconfig.iosched
+++ b/block/Kconfig.iosched
@@ -23,7 +23,8 @@
config IOSCHED_CFQ
tristate "CFQ I/O scheduler"
- select BLK_CGROUP if CFQ_GROUP_IOSCHED
+ # If BLK_CGROUP is a module, CFQ has to be built as module.
+ depends on (BLK_CGROUP=m && m) || !BLK_CGROUP || BLK_CGROUP=y
default y
---help---
The CFQ I/O scheduler tries to distribute bandwidth equally
@@ -33,22 +34,15 @@
This is the default I/O scheduler.
+ Note: If BLK_CGROUP=m, then CFQ can be built only as module.
+
config CFQ_GROUP_IOSCHED
bool "CFQ Group Scheduling support"
- depends on IOSCHED_CFQ && CGROUPS
+ depends on IOSCHED_CFQ && BLK_CGROUP
default n
---help---
Enable group IO scheduling in CFQ.
-config DEBUG_CFQ_IOSCHED
- bool "Debug CFQ Scheduling"
- depends on CFQ_GROUP_IOSCHED
- select DEBUG_BLK_CGROUP
- default n
- ---help---
- Enable CFQ IO scheduling debugging in CFQ. Currently it makes
- blktrace output more verbose.
-
choice
prompt "Default I/O scheduler"
default DEFAULT_CFQ
diff --git a/block/Makefile b/block/Makefile
index cb2d515..0bb499a 100644
--- a/block/Makefile
+++ b/block/Makefile
@@ -5,7 +5,7 @@
obj-$(CONFIG_BLOCK) := elevator.o blk-core.o blk-tag.o blk-sysfs.o \
blk-barrier.o blk-settings.o blk-ioc.o blk-map.o \
blk-exec.o blk-merge.o blk-softirq.o blk-timeout.o \
- blk-iopoll.o ioctl.o genhd.o scsi_ioctl.o
+ blk-iopoll.o blk-lib.o ioctl.o genhd.o scsi_ioctl.o
obj-$(CONFIG_BLK_DEV_BSG) += bsg.o
obj-$(CONFIG_BLK_CGROUP) += blk-cgroup.o
diff --git a/block/blk-barrier.c b/block/blk-barrier.c
index 6d88544..0d710c9 100644
--- a/block/blk-barrier.c
+++ b/block/blk-barrier.c
@@ -286,26 +286,31 @@
set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
clear_bit(BIO_UPTODATE, &bio->bi_flags);
}
-
- complete(bio->bi_private);
+ if (bio->bi_private)
+ complete(bio->bi_private);
+ bio_put(bio);
}
/**
* blkdev_issue_flush - queue a flush
* @bdev: blockdev to issue flush for
+ * @gfp_mask: memory allocation flags (for bio_alloc)
* @error_sector: error sector
+ * @flags: BLKDEV_IFL_* flags to control behaviour
*
* Description:
* Issue a flush for the block device in question. Caller can supply
* room for storing the error offset in case of a flush error, if they
- * wish to.
+ * wish to. If WAIT flag is not passed then caller may check only what
+ * request was pushed in some internal queue for later handling.
*/
-int blkdev_issue_flush(struct block_device *bdev, sector_t *error_sector)
+int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
+ sector_t *error_sector, unsigned long flags)
{
DECLARE_COMPLETION_ONSTACK(wait);
struct request_queue *q;
struct bio *bio;
- int ret;
+ int ret = 0;
if (bdev->bd_disk == NULL)
return -ENXIO;
@@ -314,23 +319,25 @@
if (!q)
return -ENXIO;
- bio = bio_alloc(GFP_KERNEL, 0);
+ bio = bio_alloc(gfp_mask, 0);
bio->bi_end_io = bio_end_empty_barrier;
- bio->bi_private = &wait;
bio->bi_bdev = bdev;
+ if (test_bit(BLKDEV_WAIT, &flags))
+ bio->bi_private = &wait;
+
+ bio_get(bio);
submit_bio(WRITE_BARRIER, bio);
+ if (test_bit(BLKDEV_WAIT, &flags)) {
+ wait_for_completion(&wait);
+ /*
+ * The driver must store the error location in ->bi_sector, if
+ * it supports it. For non-stacked drivers, this should be
+ * copied from blk_rq_pos(rq).
+ */
+ if (error_sector)
+ *error_sector = bio->bi_sector;
+ }
- wait_for_completion(&wait);
-
- /*
- * The driver must store the error location in ->bi_sector, if
- * it supports it. For non-stacked drivers, this should be copied
- * from blk_rq_pos(rq).
- */
- if (error_sector)
- *error_sector = bio->bi_sector;
-
- ret = 0;
if (bio_flagged(bio, BIO_EOPNOTSUPP))
ret = -EOPNOTSUPP;
else if (!bio_flagged(bio, BIO_UPTODATE))
@@ -340,107 +347,3 @@
return ret;
}
EXPORT_SYMBOL(blkdev_issue_flush);
-
-static void blkdev_discard_end_io(struct bio *bio, int err)
-{
- if (err) {
- if (err == -EOPNOTSUPP)
- set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
- clear_bit(BIO_UPTODATE, &bio->bi_flags);
- }
-
- if (bio->bi_private)
- complete(bio->bi_private);
- __free_page(bio_page(bio));
-
- bio_put(bio);
-}
-
-/**
- * blkdev_issue_discard - queue a discard
- * @bdev: blockdev to issue discard for
- * @sector: start sector
- * @nr_sects: number of sectors to discard
- * @gfp_mask: memory allocation flags (for bio_alloc)
- * @flags: DISCARD_FL_* flags to control behaviour
- *
- * Description:
- * Issue a discard request for the sectors in question.
- */
-int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
- sector_t nr_sects, gfp_t gfp_mask, int flags)
-{
- DECLARE_COMPLETION_ONSTACK(wait);
- struct request_queue *q = bdev_get_queue(bdev);
- int type = flags & DISCARD_FL_BARRIER ?
- DISCARD_BARRIER : DISCARD_NOBARRIER;
- struct bio *bio;
- struct page *page;
- int ret = 0;
-
- if (!q)
- return -ENXIO;
-
- if (!blk_queue_discard(q))
- return -EOPNOTSUPP;
-
- while (nr_sects && !ret) {
- unsigned int sector_size = q->limits.logical_block_size;
- unsigned int max_discard_sectors =
- min(q->limits.max_discard_sectors, UINT_MAX >> 9);
-
- bio = bio_alloc(gfp_mask, 1);
- if (!bio)
- goto out;
- bio->bi_sector = sector;
- bio->bi_end_io = blkdev_discard_end_io;
- bio->bi_bdev = bdev;
- if (flags & DISCARD_FL_WAIT)
- bio->bi_private = &wait;
-
- /*
- * Add a zeroed one-sector payload as that's what
- * our current implementations need. If we'll ever need
- * more the interface will need revisiting.
- */
- page = alloc_page(gfp_mask | __GFP_ZERO);
- if (!page)
- goto out_free_bio;
- if (bio_add_pc_page(q, bio, page, sector_size, 0) < sector_size)
- goto out_free_page;
-
- /*
- * And override the bio size - the way discard works we
- * touch many more blocks on disk than the actual payload
- * length.
- */
- if (nr_sects > max_discard_sectors) {
- bio->bi_size = max_discard_sectors << 9;
- nr_sects -= max_discard_sectors;
- sector += max_discard_sectors;
- } else {
- bio->bi_size = nr_sects << 9;
- nr_sects = 0;
- }
-
- bio_get(bio);
- submit_bio(type, bio);
-
- if (flags & DISCARD_FL_WAIT)
- wait_for_completion(&wait);
-
- if (bio_flagged(bio, BIO_EOPNOTSUPP))
- ret = -EOPNOTSUPP;
- else if (!bio_flagged(bio, BIO_UPTODATE))
- ret = -EIO;
- bio_put(bio);
- }
- return ret;
-out_free_page:
- __free_page(page);
-out_free_bio:
- bio_put(bio);
-out:
- return -ENOMEM;
-}
-EXPORT_SYMBOL(blkdev_issue_discard);
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 5fe03de..d02bbf8 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -15,8 +15,12 @@
#include <linux/kdev_t.h>
#include <linux/module.h>
#include <linux/err.h>
+#include <linux/blkdev.h>
#include <linux/slab.h>
#include "blk-cgroup.h"
+#include <linux/genhd.h>
+
+#define MAX_KEY_LEN 100
static DEFINE_SPINLOCK(blkio_list_lock);
static LIST_HEAD(blkio_list);
@@ -49,6 +53,32 @@
};
EXPORT_SYMBOL_GPL(blkio_subsys);
+static inline void blkio_policy_insert_node(struct blkio_cgroup *blkcg,
+ struct blkio_policy_node *pn)
+{
+ list_add(&pn->node, &blkcg->policy_list);
+}
+
+/* Must be called with blkcg->lock held */
+static inline void blkio_policy_delete_node(struct blkio_policy_node *pn)
+{
+ list_del(&pn->node);
+}
+
+/* Must be called with blkcg->lock held */
+static struct blkio_policy_node *
+blkio_policy_search_node(const struct blkio_cgroup *blkcg, dev_t dev)
+{
+ struct blkio_policy_node *pn;
+
+ list_for_each_entry(pn, &blkcg->policy_list, node) {
+ if (pn->dev == dev)
+ return pn;
+ }
+
+ return NULL;
+}
+
struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup)
{
return container_of(cgroup_subsys_state(cgroup, blkio_subsys_id),
@@ -56,13 +86,259 @@
}
EXPORT_SYMBOL_GPL(cgroup_to_blkio_cgroup);
-void blkiocg_update_blkio_group_stats(struct blkio_group *blkg,
- unsigned long time, unsigned long sectors)
+/*
+ * Add to the appropriate stat variable depending on the request type.
+ * This should be called with the blkg->stats_lock held.
+ */
+static void blkio_add_stat(uint64_t *stat, uint64_t add, bool direction,
+ bool sync)
{
- blkg->time += time;
- blkg->sectors += sectors;
+ if (direction)
+ stat[BLKIO_STAT_WRITE] += add;
+ else
+ stat[BLKIO_STAT_READ] += add;
+ if (sync)
+ stat[BLKIO_STAT_SYNC] += add;
+ else
+ stat[BLKIO_STAT_ASYNC] += add;
}
-EXPORT_SYMBOL_GPL(blkiocg_update_blkio_group_stats);
+
+/*
+ * Decrements the appropriate stat variable if non-zero depending on the
+ * request type. Panics on value being zero.
+ * This should be called with the blkg->stats_lock held.
+ */
+static void blkio_check_and_dec_stat(uint64_t *stat, bool direction, bool sync)
+{
+ if (direction) {
+ BUG_ON(stat[BLKIO_STAT_WRITE] == 0);
+ stat[BLKIO_STAT_WRITE]--;
+ } else {
+ BUG_ON(stat[BLKIO_STAT_READ] == 0);
+ stat[BLKIO_STAT_READ]--;
+ }
+ if (sync) {
+ BUG_ON(stat[BLKIO_STAT_SYNC] == 0);
+ stat[BLKIO_STAT_SYNC]--;
+ } else {
+ BUG_ON(stat[BLKIO_STAT_ASYNC] == 0);
+ stat[BLKIO_STAT_ASYNC]--;
+ }
+}
+
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+/* This should be called with the blkg->stats_lock held. */
+static void blkio_set_start_group_wait_time(struct blkio_group *blkg,
+ struct blkio_group *curr_blkg)
+{
+ if (blkio_blkg_waiting(&blkg->stats))
+ return;
+ if (blkg == curr_blkg)
+ return;
+ blkg->stats.start_group_wait_time = sched_clock();
+ blkio_mark_blkg_waiting(&blkg->stats);
+}
+
+/* This should be called with the blkg->stats_lock held. */
+static void blkio_update_group_wait_time(struct blkio_group_stats *stats)
+{
+ unsigned long long now;
+
+ if (!blkio_blkg_waiting(stats))
+ return;
+
+ now = sched_clock();
+ if (time_after64(now, stats->start_group_wait_time))
+ stats->group_wait_time += now - stats->start_group_wait_time;
+ blkio_clear_blkg_waiting(stats);
+}
+
+/* This should be called with the blkg->stats_lock held. */
+static void blkio_end_empty_time(struct blkio_group_stats *stats)
+{
+ unsigned long long now;
+
+ if (!blkio_blkg_empty(stats))
+ return;
+
+ now = sched_clock();
+ if (time_after64(now, stats->start_empty_time))
+ stats->empty_time += now - stats->start_empty_time;
+ blkio_clear_blkg_empty(stats);
+}
+
+void blkiocg_update_set_idle_time_stats(struct blkio_group *blkg)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&blkg->stats_lock, flags);
+ BUG_ON(blkio_blkg_idling(&blkg->stats));
+ blkg->stats.start_idle_time = sched_clock();
+ blkio_mark_blkg_idling(&blkg->stats);
+ spin_unlock_irqrestore(&blkg->stats_lock, flags);
+}
+EXPORT_SYMBOL_GPL(blkiocg_update_set_idle_time_stats);
+
+void blkiocg_update_idle_time_stats(struct blkio_group *blkg)
+{
+ unsigned long flags;
+ unsigned long long now;
+ struct blkio_group_stats *stats;
+
+ spin_lock_irqsave(&blkg->stats_lock, flags);
+ stats = &blkg->stats;
+ if (blkio_blkg_idling(stats)) {
+ now = sched_clock();
+ if (time_after64(now, stats->start_idle_time))
+ stats->idle_time += now - stats->start_idle_time;
+ blkio_clear_blkg_idling(stats);
+ }
+ spin_unlock_irqrestore(&blkg->stats_lock, flags);
+}
+EXPORT_SYMBOL_GPL(blkiocg_update_idle_time_stats);
+
+void blkiocg_update_avg_queue_size_stats(struct blkio_group *blkg)
+{
+ unsigned long flags;
+ struct blkio_group_stats *stats;
+
+ spin_lock_irqsave(&blkg->stats_lock, flags);
+ stats = &blkg->stats;
+ stats->avg_queue_size_sum +=
+ stats->stat_arr[BLKIO_STAT_QUEUED][BLKIO_STAT_READ] +
+ stats->stat_arr[BLKIO_STAT_QUEUED][BLKIO_STAT_WRITE];
+ stats->avg_queue_size_samples++;
+ blkio_update_group_wait_time(stats);
+ spin_unlock_irqrestore(&blkg->stats_lock, flags);
+}
+EXPORT_SYMBOL_GPL(blkiocg_update_avg_queue_size_stats);
+
+void blkiocg_set_start_empty_time(struct blkio_group *blkg)
+{
+ unsigned long flags;
+ struct blkio_group_stats *stats;
+
+ spin_lock_irqsave(&blkg->stats_lock, flags);
+ stats = &blkg->stats;
+
+ if (stats->stat_arr[BLKIO_STAT_QUEUED][BLKIO_STAT_READ] ||
+ stats->stat_arr[BLKIO_STAT_QUEUED][BLKIO_STAT_WRITE]) {
+ spin_unlock_irqrestore(&blkg->stats_lock, flags);
+ return;
+ }
+
+ /*
+ * group is already marked empty. This can happen if cfqq got new
+ * request in parent group and moved to this group while being added
+ * to service tree. Just ignore the event and move on.
+ */
+ if(blkio_blkg_empty(stats)) {
+ spin_unlock_irqrestore(&blkg->stats_lock, flags);
+ return;
+ }
+
+ stats->start_empty_time = sched_clock();
+ blkio_mark_blkg_empty(stats);
+ spin_unlock_irqrestore(&blkg->stats_lock, flags);
+}
+EXPORT_SYMBOL_GPL(blkiocg_set_start_empty_time);
+
+void blkiocg_update_dequeue_stats(struct blkio_group *blkg,
+ unsigned long dequeue)
+{
+ blkg->stats.dequeue += dequeue;
+}
+EXPORT_SYMBOL_GPL(blkiocg_update_dequeue_stats);
+#else
+static inline void blkio_set_start_group_wait_time(struct blkio_group *blkg,
+ struct blkio_group *curr_blkg) {}
+static inline void blkio_end_empty_time(struct blkio_group_stats *stats) {}
+#endif
+
+void blkiocg_update_io_add_stats(struct blkio_group *blkg,
+ struct blkio_group *curr_blkg, bool direction,
+ bool sync)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&blkg->stats_lock, flags);
+ blkio_add_stat(blkg->stats.stat_arr[BLKIO_STAT_QUEUED], 1, direction,
+ sync);
+ blkio_end_empty_time(&blkg->stats);
+ blkio_set_start_group_wait_time(blkg, curr_blkg);
+ spin_unlock_irqrestore(&blkg->stats_lock, flags);
+}
+EXPORT_SYMBOL_GPL(blkiocg_update_io_add_stats);
+
+void blkiocg_update_io_remove_stats(struct blkio_group *blkg,
+ bool direction, bool sync)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&blkg->stats_lock, flags);
+ blkio_check_and_dec_stat(blkg->stats.stat_arr[BLKIO_STAT_QUEUED],
+ direction, sync);
+ spin_unlock_irqrestore(&blkg->stats_lock, flags);
+}
+EXPORT_SYMBOL_GPL(blkiocg_update_io_remove_stats);
+
+void blkiocg_update_timeslice_used(struct blkio_group *blkg, unsigned long time)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&blkg->stats_lock, flags);
+ blkg->stats.time += time;
+ spin_unlock_irqrestore(&blkg->stats_lock, flags);
+}
+EXPORT_SYMBOL_GPL(blkiocg_update_timeslice_used);
+
+void blkiocg_update_dispatch_stats(struct blkio_group *blkg,
+ uint64_t bytes, bool direction, bool sync)
+{
+ struct blkio_group_stats *stats;
+ unsigned long flags;
+
+ spin_lock_irqsave(&blkg->stats_lock, flags);
+ stats = &blkg->stats;
+ stats->sectors += bytes >> 9;
+ blkio_add_stat(stats->stat_arr[BLKIO_STAT_SERVICED], 1, direction,
+ sync);
+ blkio_add_stat(stats->stat_arr[BLKIO_STAT_SERVICE_BYTES], bytes,
+ direction, sync);
+ spin_unlock_irqrestore(&blkg->stats_lock, flags);
+}
+EXPORT_SYMBOL_GPL(blkiocg_update_dispatch_stats);
+
+void blkiocg_update_completion_stats(struct blkio_group *blkg,
+ uint64_t start_time, uint64_t io_start_time, bool direction, bool sync)
+{
+ struct blkio_group_stats *stats;
+ unsigned long flags;
+ unsigned long long now = sched_clock();
+
+ spin_lock_irqsave(&blkg->stats_lock, flags);
+ stats = &blkg->stats;
+ if (time_after64(now, io_start_time))
+ blkio_add_stat(stats->stat_arr[BLKIO_STAT_SERVICE_TIME],
+ now - io_start_time, direction, sync);
+ if (time_after64(io_start_time, start_time))
+ blkio_add_stat(stats->stat_arr[BLKIO_STAT_WAIT_TIME],
+ io_start_time - start_time, direction, sync);
+ spin_unlock_irqrestore(&blkg->stats_lock, flags);
+}
+EXPORT_SYMBOL_GPL(blkiocg_update_completion_stats);
+
+void blkiocg_update_io_merged_stats(struct blkio_group *blkg, bool direction,
+ bool sync)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&blkg->stats_lock, flags);
+ blkio_add_stat(blkg->stats.stat_arr[BLKIO_STAT_MERGED], 1, direction,
+ sync);
+ spin_unlock_irqrestore(&blkg->stats_lock, flags);
+}
+EXPORT_SYMBOL_GPL(blkiocg_update_io_merged_stats);
void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
struct blkio_group *blkg, void *key, dev_t dev)
@@ -70,14 +346,13 @@
unsigned long flags;
spin_lock_irqsave(&blkcg->lock, flags);
+ spin_lock_init(&blkg->stats_lock);
rcu_assign_pointer(blkg->key, key);
blkg->blkcg_id = css_id(&blkcg->css);
hlist_add_head_rcu(&blkg->blkcg_node, &blkcg->blkg_list);
spin_unlock_irqrestore(&blkcg->lock, flags);
-#ifdef CONFIG_DEBUG_BLK_CGROUP
/* Need to take css reference ? */
cgroup_path(blkcg->css.cgroup, blkg->path, sizeof(blkg->path));
-#endif
blkg->dev = dev;
}
EXPORT_SYMBOL_GPL(blkiocg_add_blkio_group);
@@ -154,6 +429,7 @@
struct blkio_group *blkg;
struct hlist_node *n;
struct blkio_policy_type *blkiop;
+ struct blkio_policy_node *pn;
if (val < BLKIO_WEIGHT_MIN || val > BLKIO_WEIGHT_MAX)
return -EINVAL;
@@ -162,7 +438,13 @@
spin_lock(&blkio_list_lock);
spin_lock_irq(&blkcg->lock);
blkcg->weight = (unsigned int)val;
+
hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) {
+ pn = blkio_policy_search_node(blkcg, blkg->dev);
+
+ if (pn)
+ continue;
+
list_for_each_entry(blkiop, &blkio_list, list)
blkiop->ops.blkio_update_group_weight_fn(blkg,
blkcg->weight);
@@ -172,13 +454,154 @@
return 0;
}
-#define SHOW_FUNCTION_PER_GROUP(__VAR) \
+static int
+blkiocg_reset_stats(struct cgroup *cgroup, struct cftype *cftype, u64 val)
+{
+ struct blkio_cgroup *blkcg;
+ struct blkio_group *blkg;
+ struct blkio_group_stats *stats;
+ struct hlist_node *n;
+ uint64_t queued[BLKIO_STAT_TOTAL];
+ int i;
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+ bool idling, waiting, empty;
+ unsigned long long now = sched_clock();
+#endif
+
+ blkcg = cgroup_to_blkio_cgroup(cgroup);
+ spin_lock_irq(&blkcg->lock);
+ hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) {
+ spin_lock(&blkg->stats_lock);
+ stats = &blkg->stats;
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+ idling = blkio_blkg_idling(stats);
+ waiting = blkio_blkg_waiting(stats);
+ empty = blkio_blkg_empty(stats);
+#endif
+ for (i = 0; i < BLKIO_STAT_TOTAL; i++)
+ queued[i] = stats->stat_arr[BLKIO_STAT_QUEUED][i];
+ memset(stats, 0, sizeof(struct blkio_group_stats));
+ for (i = 0; i < BLKIO_STAT_TOTAL; i++)
+ stats->stat_arr[BLKIO_STAT_QUEUED][i] = queued[i];
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+ if (idling) {
+ blkio_mark_blkg_idling(stats);
+ stats->start_idle_time = now;
+ }
+ if (waiting) {
+ blkio_mark_blkg_waiting(stats);
+ stats->start_group_wait_time = now;
+ }
+ if (empty) {
+ blkio_mark_blkg_empty(stats);
+ stats->start_empty_time = now;
+ }
+#endif
+ spin_unlock(&blkg->stats_lock);
+ }
+ spin_unlock_irq(&blkcg->lock);
+ return 0;
+}
+
+static void blkio_get_key_name(enum stat_sub_type type, dev_t dev, char *str,
+ int chars_left, bool diskname_only)
+{
+ snprintf(str, chars_left, "%d:%d", MAJOR(dev), MINOR(dev));
+ chars_left -= strlen(str);
+ if (chars_left <= 0) {
+ printk(KERN_WARNING
+ "Possibly incorrect cgroup stat display format");
+ return;
+ }
+ if (diskname_only)
+ return;
+ switch (type) {
+ case BLKIO_STAT_READ:
+ strlcat(str, " Read", chars_left);
+ break;
+ case BLKIO_STAT_WRITE:
+ strlcat(str, " Write", chars_left);
+ break;
+ case BLKIO_STAT_SYNC:
+ strlcat(str, " Sync", chars_left);
+ break;
+ case BLKIO_STAT_ASYNC:
+ strlcat(str, " Async", chars_left);
+ break;
+ case BLKIO_STAT_TOTAL:
+ strlcat(str, " Total", chars_left);
+ break;
+ default:
+ strlcat(str, " Invalid", chars_left);
+ }
+}
+
+static uint64_t blkio_fill_stat(char *str, int chars_left, uint64_t val,
+ struct cgroup_map_cb *cb, dev_t dev)
+{
+ blkio_get_key_name(0, dev, str, chars_left, true);
+ cb->fill(cb, str, val);
+ return val;
+}
+
+/* This should be called with blkg->stats_lock held */
+static uint64_t blkio_get_stat(struct blkio_group *blkg,
+ struct cgroup_map_cb *cb, dev_t dev, enum stat_type type)
+{
+ uint64_t disk_total;
+ char key_str[MAX_KEY_LEN];
+ enum stat_sub_type sub_type;
+
+ if (type == BLKIO_STAT_TIME)
+ return blkio_fill_stat(key_str, MAX_KEY_LEN - 1,
+ blkg->stats.time, cb, dev);
+ if (type == BLKIO_STAT_SECTORS)
+ return blkio_fill_stat(key_str, MAX_KEY_LEN - 1,
+ blkg->stats.sectors, cb, dev);
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+ if (type == BLKIO_STAT_AVG_QUEUE_SIZE) {
+ uint64_t sum = blkg->stats.avg_queue_size_sum;
+ uint64_t samples = blkg->stats.avg_queue_size_samples;
+ if (samples)
+ do_div(sum, samples);
+ else
+ sum = 0;
+ return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, sum, cb, dev);
+ }
+ if (type == BLKIO_STAT_GROUP_WAIT_TIME)
+ return blkio_fill_stat(key_str, MAX_KEY_LEN - 1,
+ blkg->stats.group_wait_time, cb, dev);
+ if (type == BLKIO_STAT_IDLE_TIME)
+ return blkio_fill_stat(key_str, MAX_KEY_LEN - 1,
+ blkg->stats.idle_time, cb, dev);
+ if (type == BLKIO_STAT_EMPTY_TIME)
+ return blkio_fill_stat(key_str, MAX_KEY_LEN - 1,
+ blkg->stats.empty_time, cb, dev);
+ if (type == BLKIO_STAT_DEQUEUE)
+ return blkio_fill_stat(key_str, MAX_KEY_LEN - 1,
+ blkg->stats.dequeue, cb, dev);
+#endif
+
+ for (sub_type = BLKIO_STAT_READ; sub_type < BLKIO_STAT_TOTAL;
+ sub_type++) {
+ blkio_get_key_name(sub_type, dev, key_str, MAX_KEY_LEN, false);
+ cb->fill(cb, key_str, blkg->stats.stat_arr[type][sub_type]);
+ }
+ disk_total = blkg->stats.stat_arr[type][BLKIO_STAT_READ] +
+ blkg->stats.stat_arr[type][BLKIO_STAT_WRITE];
+ blkio_get_key_name(BLKIO_STAT_TOTAL, dev, key_str, MAX_KEY_LEN, false);
+ cb->fill(cb, key_str, disk_total);
+ return disk_total;
+}
+
+#define SHOW_FUNCTION_PER_GROUP(__VAR, type, show_total) \
static int blkiocg_##__VAR##_read(struct cgroup *cgroup, \
- struct cftype *cftype, struct seq_file *m) \
+ struct cftype *cftype, struct cgroup_map_cb *cb) \
{ \
struct blkio_cgroup *blkcg; \
struct blkio_group *blkg; \
struct hlist_node *n; \
+ uint64_t cgroup_total = 0; \
\
if (!cgroup_lock_live_group(cgroup)) \
return -ENODEV; \
@@ -186,50 +609,295 @@
blkcg = cgroup_to_blkio_cgroup(cgroup); \
rcu_read_lock(); \
hlist_for_each_entry_rcu(blkg, n, &blkcg->blkg_list, blkcg_node) {\
- if (blkg->dev) \
- seq_printf(m, "%u:%u %lu\n", MAJOR(blkg->dev), \
- MINOR(blkg->dev), blkg->__VAR); \
+ if (blkg->dev) { \
+ spin_lock_irq(&blkg->stats_lock); \
+ cgroup_total += blkio_get_stat(blkg, cb, \
+ blkg->dev, type); \
+ spin_unlock_irq(&blkg->stats_lock); \
+ } \
} \
+ if (show_total) \
+ cb->fill(cb, "Total", cgroup_total); \
rcu_read_unlock(); \
cgroup_unlock(); \
return 0; \
}
-SHOW_FUNCTION_PER_GROUP(time);
-SHOW_FUNCTION_PER_GROUP(sectors);
+SHOW_FUNCTION_PER_GROUP(time, BLKIO_STAT_TIME, 0);
+SHOW_FUNCTION_PER_GROUP(sectors, BLKIO_STAT_SECTORS, 0);
+SHOW_FUNCTION_PER_GROUP(io_service_bytes, BLKIO_STAT_SERVICE_BYTES, 1);
+SHOW_FUNCTION_PER_GROUP(io_serviced, BLKIO_STAT_SERVICED, 1);
+SHOW_FUNCTION_PER_GROUP(io_service_time, BLKIO_STAT_SERVICE_TIME, 1);
+SHOW_FUNCTION_PER_GROUP(io_wait_time, BLKIO_STAT_WAIT_TIME, 1);
+SHOW_FUNCTION_PER_GROUP(io_merged, BLKIO_STAT_MERGED, 1);
+SHOW_FUNCTION_PER_GROUP(io_queued, BLKIO_STAT_QUEUED, 1);
#ifdef CONFIG_DEBUG_BLK_CGROUP
-SHOW_FUNCTION_PER_GROUP(dequeue);
+SHOW_FUNCTION_PER_GROUP(dequeue, BLKIO_STAT_DEQUEUE, 0);
+SHOW_FUNCTION_PER_GROUP(avg_queue_size, BLKIO_STAT_AVG_QUEUE_SIZE, 0);
+SHOW_FUNCTION_PER_GROUP(group_wait_time, BLKIO_STAT_GROUP_WAIT_TIME, 0);
+SHOW_FUNCTION_PER_GROUP(idle_time, BLKIO_STAT_IDLE_TIME, 0);
+SHOW_FUNCTION_PER_GROUP(empty_time, BLKIO_STAT_EMPTY_TIME, 0);
#endif
#undef SHOW_FUNCTION_PER_GROUP
-#ifdef CONFIG_DEBUG_BLK_CGROUP
-void blkiocg_update_blkio_group_dequeue_stats(struct blkio_group *blkg,
- unsigned long dequeue)
+static int blkio_check_dev_num(dev_t dev)
{
- blkg->dequeue += dequeue;
+ int part = 0;
+ struct gendisk *disk;
+
+ disk = get_gendisk(dev, &part);
+ if (!disk || part)
+ return -ENODEV;
+
+ return 0;
}
-EXPORT_SYMBOL_GPL(blkiocg_update_blkio_group_dequeue_stats);
-#endif
+
+static int blkio_policy_parse_and_set(char *buf,
+ struct blkio_policy_node *newpn)
+{
+ char *s[4], *p, *major_s = NULL, *minor_s = NULL;
+ int ret;
+ unsigned long major, minor, temp;
+ int i = 0;
+ dev_t dev;
+
+ memset(s, 0, sizeof(s));
+
+ while ((p = strsep(&buf, " ")) != NULL) {
+ if (!*p)
+ continue;
+
+ s[i++] = p;
+
+ /* Prevent from inputing too many things */
+ if (i == 3)
+ break;
+ }
+
+ if (i != 2)
+ return -EINVAL;
+
+ p = strsep(&s[0], ":");
+ if (p != NULL)
+ major_s = p;
+ else
+ return -EINVAL;
+
+ minor_s = s[0];
+ if (!minor_s)
+ return -EINVAL;
+
+ ret = strict_strtoul(major_s, 10, &major);
+ if (ret)
+ return -EINVAL;
+
+ ret = strict_strtoul(minor_s, 10, &minor);
+ if (ret)
+ return -EINVAL;
+
+ dev = MKDEV(major, minor);
+
+ ret = blkio_check_dev_num(dev);
+ if (ret)
+ return ret;
+
+ newpn->dev = dev;
+
+ if (s[1] == NULL)
+ return -EINVAL;
+
+ ret = strict_strtoul(s[1], 10, &temp);
+ if (ret || (temp < BLKIO_WEIGHT_MIN && temp > 0) ||
+ temp > BLKIO_WEIGHT_MAX)
+ return -EINVAL;
+
+ newpn->weight = temp;
+
+ return 0;
+}
+
+unsigned int blkcg_get_weight(struct blkio_cgroup *blkcg,
+ dev_t dev)
+{
+ struct blkio_policy_node *pn;
+
+ pn = blkio_policy_search_node(blkcg, dev);
+ if (pn)
+ return pn->weight;
+ else
+ return blkcg->weight;
+}
+EXPORT_SYMBOL_GPL(blkcg_get_weight);
+
+
+static int blkiocg_weight_device_write(struct cgroup *cgrp, struct cftype *cft,
+ const char *buffer)
+{
+ int ret = 0;
+ char *buf;
+ struct blkio_policy_node *newpn, *pn;
+ struct blkio_cgroup *blkcg;
+ struct blkio_group *blkg;
+ int keep_newpn = 0;
+ struct hlist_node *n;
+ struct blkio_policy_type *blkiop;
+
+ buf = kstrdup(buffer, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ newpn = kzalloc(sizeof(*newpn), GFP_KERNEL);
+ if (!newpn) {
+ ret = -ENOMEM;
+ goto free_buf;
+ }
+
+ ret = blkio_policy_parse_and_set(buf, newpn);
+ if (ret)
+ goto free_newpn;
+
+ blkcg = cgroup_to_blkio_cgroup(cgrp);
+
+ spin_lock_irq(&blkcg->lock);
+
+ pn = blkio_policy_search_node(blkcg, newpn->dev);
+ if (!pn) {
+ if (newpn->weight != 0) {
+ blkio_policy_insert_node(blkcg, newpn);
+ keep_newpn = 1;
+ }
+ spin_unlock_irq(&blkcg->lock);
+ goto update_io_group;
+ }
+
+ if (newpn->weight == 0) {
+ /* weight == 0 means deleteing a specific weight */
+ blkio_policy_delete_node(pn);
+ spin_unlock_irq(&blkcg->lock);
+ goto update_io_group;
+ }
+ spin_unlock_irq(&blkcg->lock);
+
+ pn->weight = newpn->weight;
+
+update_io_group:
+ /* update weight for each cfqg */
+ spin_lock(&blkio_list_lock);
+ spin_lock_irq(&blkcg->lock);
+
+ hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) {
+ if (newpn->dev == blkg->dev) {
+ list_for_each_entry(blkiop, &blkio_list, list)
+ blkiop->ops.blkio_update_group_weight_fn(blkg,
+ newpn->weight ?
+ newpn->weight :
+ blkcg->weight);
+ }
+ }
+
+ spin_unlock_irq(&blkcg->lock);
+ spin_unlock(&blkio_list_lock);
+
+free_newpn:
+ if (!keep_newpn)
+ kfree(newpn);
+free_buf:
+ kfree(buf);
+ return ret;
+}
+
+static int blkiocg_weight_device_read(struct cgroup *cgrp, struct cftype *cft,
+ struct seq_file *m)
+{
+ struct blkio_cgroup *blkcg;
+ struct blkio_policy_node *pn;
+
+ seq_printf(m, "dev\tweight\n");
+
+ blkcg = cgroup_to_blkio_cgroup(cgrp);
+ if (list_empty(&blkcg->policy_list))
+ goto out;
+
+ spin_lock_irq(&blkcg->lock);
+ list_for_each_entry(pn, &blkcg->policy_list, node) {
+ seq_printf(m, "%u:%u\t%u\n", MAJOR(pn->dev),
+ MINOR(pn->dev), pn->weight);
+ }
+ spin_unlock_irq(&blkcg->lock);
+
+out:
+ return 0;
+}
struct cftype blkio_files[] = {
{
+ .name = "weight_device",
+ .read_seq_string = blkiocg_weight_device_read,
+ .write_string = blkiocg_weight_device_write,
+ .max_write_len = 256,
+ },
+ {
.name = "weight",
.read_u64 = blkiocg_weight_read,
.write_u64 = blkiocg_weight_write,
},
{
.name = "time",
- .read_seq_string = blkiocg_time_read,
+ .read_map = blkiocg_time_read,
},
{
.name = "sectors",
- .read_seq_string = blkiocg_sectors_read,
+ .read_map = blkiocg_sectors_read,
+ },
+ {
+ .name = "io_service_bytes",
+ .read_map = blkiocg_io_service_bytes_read,
+ },
+ {
+ .name = "io_serviced",
+ .read_map = blkiocg_io_serviced_read,
+ },
+ {
+ .name = "io_service_time",
+ .read_map = blkiocg_io_service_time_read,
+ },
+ {
+ .name = "io_wait_time",
+ .read_map = blkiocg_io_wait_time_read,
+ },
+ {
+ .name = "io_merged",
+ .read_map = blkiocg_io_merged_read,
+ },
+ {
+ .name = "io_queued",
+ .read_map = blkiocg_io_queued_read,
+ },
+ {
+ .name = "reset_stats",
+ .write_u64 = blkiocg_reset_stats,
},
#ifdef CONFIG_DEBUG_BLK_CGROUP
- {
+ {
+ .name = "avg_queue_size",
+ .read_map = blkiocg_avg_queue_size_read,
+ },
+ {
+ .name = "group_wait_time",
+ .read_map = blkiocg_group_wait_time_read,
+ },
+ {
+ .name = "idle_time",
+ .read_map = blkiocg_idle_time_read,
+ },
+ {
+ .name = "empty_time",
+ .read_map = blkiocg_empty_time_read,
+ },
+ {
.name = "dequeue",
- .read_seq_string = blkiocg_dequeue_read,
- },
+ .read_map = blkiocg_dequeue_read,
+ },
#endif
};
@@ -246,6 +914,7 @@
struct blkio_group *blkg;
void *key;
struct blkio_policy_type *blkiop;
+ struct blkio_policy_node *pn, *pntmp;
rcu_read_lock();
remove_entry:
@@ -276,7 +945,12 @@
blkiop->ops.blkio_unlink_group_fn(key, blkg);
spin_unlock(&blkio_list_lock);
goto remove_entry;
+
done:
+ list_for_each_entry_safe(pn, pntmp, &blkcg->policy_list, node) {
+ blkio_policy_delete_node(pn);
+ kfree(pn);
+ }
free_css_id(&blkio_subsys, &blkcg->css);
rcu_read_unlock();
if (blkcg != &blkio_root_cgroup)
@@ -307,6 +981,7 @@
spin_lock_init(&blkcg->lock);
INIT_HLIST_HEAD(&blkcg->blkg_list);
+ INIT_LIST_HEAD(&blkcg->policy_list);
return &blkcg->css;
}
diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
index 8ccc204..2b866ec 100644
--- a/block/blk-cgroup.h
+++ b/block/blk-cgroup.h
@@ -23,11 +23,84 @@
#define blkio_subsys_id blkio_subsys.subsys_id
#endif
+enum stat_type {
+ /* Total time spent (in ns) between request dispatch to the driver and
+ * request completion for IOs doen by this cgroup. This may not be
+ * accurate when NCQ is turned on. */
+ BLKIO_STAT_SERVICE_TIME = 0,
+ /* Total bytes transferred */
+ BLKIO_STAT_SERVICE_BYTES,
+ /* Total IOs serviced, post merge */
+ BLKIO_STAT_SERVICED,
+ /* Total time spent waiting in scheduler queue in ns */
+ BLKIO_STAT_WAIT_TIME,
+ /* Number of IOs merged */
+ BLKIO_STAT_MERGED,
+ /* Number of IOs queued up */
+ BLKIO_STAT_QUEUED,
+ /* All the single valued stats go below this */
+ BLKIO_STAT_TIME,
+ BLKIO_STAT_SECTORS,
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+ BLKIO_STAT_AVG_QUEUE_SIZE,
+ BLKIO_STAT_IDLE_TIME,
+ BLKIO_STAT_EMPTY_TIME,
+ BLKIO_STAT_GROUP_WAIT_TIME,
+ BLKIO_STAT_DEQUEUE
+#endif
+};
+
+enum stat_sub_type {
+ BLKIO_STAT_READ = 0,
+ BLKIO_STAT_WRITE,
+ BLKIO_STAT_SYNC,
+ BLKIO_STAT_ASYNC,
+ BLKIO_STAT_TOTAL
+};
+
+/* blkg state flags */
+enum blkg_state_flags {
+ BLKG_waiting = 0,
+ BLKG_idling,
+ BLKG_empty,
+};
+
struct blkio_cgroup {
struct cgroup_subsys_state css;
unsigned int weight;
spinlock_t lock;
struct hlist_head blkg_list;
+ struct list_head policy_list; /* list of blkio_policy_node */
+};
+
+struct blkio_group_stats {
+ /* total disk time and nr sectors dispatched by this group */
+ uint64_t time;
+ uint64_t sectors;
+ uint64_t stat_arr[BLKIO_STAT_QUEUED + 1][BLKIO_STAT_TOTAL];
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+ /* Sum of number of IOs queued across all samples */
+ uint64_t avg_queue_size_sum;
+ /* Count of samples taken for average */
+ uint64_t avg_queue_size_samples;
+ /* How many times this group has been removed from service tree */
+ unsigned long dequeue;
+
+ /* Total time spent waiting for it to be assigned a timeslice. */
+ uint64_t group_wait_time;
+ uint64_t start_group_wait_time;
+
+ /* Time spent idling for this blkio_group */
+ uint64_t idle_time;
+ uint64_t start_idle_time;
+ /*
+ * Total time when we have requests queued and do not contain the
+ * current active queue.
+ */
+ uint64_t empty_time;
+ uint64_t start_empty_time;
+ uint16_t flags;
+#endif
};
struct blkio_group {
@@ -35,20 +108,25 @@
void *key;
struct hlist_node blkcg_node;
unsigned short blkcg_id;
-#ifdef CONFIG_DEBUG_BLK_CGROUP
/* Store cgroup path */
char path[128];
- /* How many times this group has been removed from service tree */
- unsigned long dequeue;
-#endif
/* The device MKDEV(major, minor), this group has been created for */
- dev_t dev;
+ dev_t dev;
- /* total disk time and nr sectors dispatched by this group */
- unsigned long time;
- unsigned long sectors;
+ /* Need to serialize the stats in the case of reset/update */
+ spinlock_t stats_lock;
+ struct blkio_group_stats stats;
};
+struct blkio_policy_node {
+ struct list_head node;
+ dev_t dev;
+ unsigned int weight;
+};
+
+extern unsigned int blkcg_get_weight(struct blkio_cgroup *blkcg,
+ dev_t dev);
+
typedef void (blkio_unlink_group_fn) (void *key, struct blkio_group *blkg);
typedef void (blkio_update_group_weight_fn) (struct blkio_group *blkg,
unsigned int weight);
@@ -67,6 +145,11 @@
extern void blkio_policy_register(struct blkio_policy_type *);
extern void blkio_policy_unregister(struct blkio_policy_type *);
+static inline char *blkg_path(struct blkio_group *blkg)
+{
+ return blkg->path;
+}
+
#else
struct blkio_group {
@@ -78,6 +161,8 @@
static inline void blkio_policy_register(struct blkio_policy_type *blkiop) { }
static inline void blkio_policy_unregister(struct blkio_policy_type *blkiop) { }
+static inline char *blkg_path(struct blkio_group *blkg) { return NULL; }
+
#endif
#define BLKIO_WEIGHT_MIN 100
@@ -85,16 +170,42 @@
#define BLKIO_WEIGHT_DEFAULT 500
#ifdef CONFIG_DEBUG_BLK_CGROUP
-static inline char *blkg_path(struct blkio_group *blkg)
-{
- return blkg->path;
-}
-void blkiocg_update_blkio_group_dequeue_stats(struct blkio_group *blkg,
+void blkiocg_update_avg_queue_size_stats(struct blkio_group *blkg);
+void blkiocg_update_dequeue_stats(struct blkio_group *blkg,
unsigned long dequeue);
+void blkiocg_update_set_idle_time_stats(struct blkio_group *blkg);
+void blkiocg_update_idle_time_stats(struct blkio_group *blkg);
+void blkiocg_set_start_empty_time(struct blkio_group *blkg);
+
+#define BLKG_FLAG_FNS(name) \
+static inline void blkio_mark_blkg_##name( \
+ struct blkio_group_stats *stats) \
+{ \
+ stats->flags |= (1 << BLKG_##name); \
+} \
+static inline void blkio_clear_blkg_##name( \
+ struct blkio_group_stats *stats) \
+{ \
+ stats->flags &= ~(1 << BLKG_##name); \
+} \
+static inline int blkio_blkg_##name(struct blkio_group_stats *stats) \
+{ \
+ return (stats->flags & (1 << BLKG_##name)) != 0; \
+} \
+
+BLKG_FLAG_FNS(waiting)
+BLKG_FLAG_FNS(idling)
+BLKG_FLAG_FNS(empty)
+#undef BLKG_FLAG_FNS
#else
-static inline char *blkg_path(struct blkio_group *blkg) { return NULL; }
-static inline void blkiocg_update_blkio_group_dequeue_stats(
- struct blkio_group *blkg, unsigned long dequeue) {}
+static inline void blkiocg_update_avg_queue_size_stats(
+ struct blkio_group *blkg) {}
+static inline void blkiocg_update_dequeue_stats(struct blkio_group *blkg,
+ unsigned long dequeue) {}
+static inline void blkiocg_update_set_idle_time_stats(struct blkio_group *blkg)
+{}
+static inline void blkiocg_update_idle_time_stats(struct blkio_group *blkg) {}
+static inline void blkiocg_set_start_empty_time(struct blkio_group *blkg) {}
#endif
#if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE)
@@ -105,26 +216,43 @@
extern int blkiocg_del_blkio_group(struct blkio_group *blkg);
extern struct blkio_group *blkiocg_lookup_group(struct blkio_cgroup *blkcg,
void *key);
-void blkiocg_update_blkio_group_stats(struct blkio_group *blkg,
- unsigned long time, unsigned long sectors);
+void blkiocg_update_timeslice_used(struct blkio_group *blkg,
+ unsigned long time);
+void blkiocg_update_dispatch_stats(struct blkio_group *blkg, uint64_t bytes,
+ bool direction, bool sync);
+void blkiocg_update_completion_stats(struct blkio_group *blkg,
+ uint64_t start_time, uint64_t io_start_time, bool direction, bool sync);
+void blkiocg_update_io_merged_stats(struct blkio_group *blkg, bool direction,
+ bool sync);
+void blkiocg_update_io_add_stats(struct blkio_group *blkg,
+ struct blkio_group *curr_blkg, bool direction, bool sync);
+void blkiocg_update_io_remove_stats(struct blkio_group *blkg,
+ bool direction, bool sync);
#else
struct cgroup;
static inline struct blkio_cgroup *
cgroup_to_blkio_cgroup(struct cgroup *cgroup) { return NULL; }
static inline void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
- struct blkio_group *blkg, void *key, dev_t dev)
-{
-}
+ struct blkio_group *blkg, void *key, dev_t dev) {}
static inline int
blkiocg_del_blkio_group(struct blkio_group *blkg) { return 0; }
static inline struct blkio_group *
blkiocg_lookup_group(struct blkio_cgroup *blkcg, void *key) { return NULL; }
-static inline void blkiocg_update_blkio_group_stats(struct blkio_group *blkg,
- unsigned long time, unsigned long sectors)
-{
-}
+static inline void blkiocg_update_timeslice_used(struct blkio_group *blkg,
+ unsigned long time) {}
+static inline void blkiocg_update_dispatch_stats(struct blkio_group *blkg,
+ uint64_t bytes, bool direction, bool sync) {}
+static inline void blkiocg_update_completion_stats(struct blkio_group *blkg,
+ uint64_t start_time, uint64_t io_start_time, bool direction,
+ bool sync) {}
+static inline void blkiocg_update_io_merged_stats(struct blkio_group *blkg,
+ bool direction, bool sync) {}
+static inline void blkiocg_update_io_add_stats(struct blkio_group *blkg,
+ struct blkio_group *curr_blkg, bool direction, bool sync) {}
+static inline void blkiocg_update_io_remove_stats(struct blkio_group *blkg,
+ bool direction, bool sync) {}
#endif
#endif /* _BLK_CGROUP_H */
diff --git a/block/blk-core.c b/block/blk-core.c
index 9fe174d..e9a5ae2 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -127,6 +127,7 @@
rq->tag = -1;
rq->ref_count = 1;
rq->start_time = jiffies;
+ set_start_time_ns(rq);
}
EXPORT_SYMBOL(blk_rq_init);
@@ -450,6 +451,7 @@
*/
blk_sync_queue(q);
+ del_timer_sync(&q->backing_dev_info.laptop_mode_wb_timer);
mutex_lock(&q->sysfs_lock);
queue_flag_set_unlocked(QUEUE_FLAG_DEAD, q);
mutex_unlock(&q->sysfs_lock);
@@ -510,6 +512,8 @@
return NULL;
}
+ setup_timer(&q->backing_dev_info.laptop_mode_wb_timer,
+ laptop_mode_timer_fn, (unsigned long) q);
init_timer(&q->unplug_timer);
setup_timer(&q->timeout, blk_rq_timed_out_timer, (unsigned long) q);
INIT_LIST_HEAD(&q->timeout_list);
@@ -1198,6 +1202,7 @@
if (!blk_rq_cpu_valid(req))
req->cpu = bio->bi_comp_cpu;
drive_stat_acct(req, 0);
+ elv_bio_merged(q, req, bio);
if (!attempt_back_merge(q, req))
elv_merged_request(q, req, el_ret);
goto out;
@@ -1231,6 +1236,7 @@
if (!blk_rq_cpu_valid(req))
req->cpu = bio->bi_comp_cpu;
drive_stat_acct(req, 0);
+ elv_bio_merged(q, req, bio);
if (!attempt_front_merge(q, req))
elv_merged_request(q, req, el_ret);
goto out;
@@ -1855,8 +1861,10 @@
* and to it is freed is accounted as io that is in progress at
* the driver side.
*/
- if (blk_account_rq(rq))
+ if (blk_account_rq(rq)) {
q->in_flight[rq_is_sync(rq)]++;
+ set_io_start_time_ns(rq);
+ }
}
/**
@@ -2098,7 +2106,7 @@
BUG_ON(blk_queued_rq(req));
if (unlikely(laptop_mode) && blk_fs_request(req))
- laptop_io_completion();
+ laptop_io_completion(&req->q->backing_dev_info);
blk_delete_timer(req);
@@ -2517,4 +2525,3 @@
return 0;
}
-
diff --git a/block/blk-lib.c b/block/blk-lib.c
new file mode 100644
index 0000000..d0216b9
--- /dev/null
+++ b/block/blk-lib.c
@@ -0,0 +1,233 @@
+/*
+ * Functions related to generic helpers functions
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/bio.h>
+#include <linux/blkdev.h>
+#include <linux/scatterlist.h>
+
+#include "blk.h"
+
+static void blkdev_discard_end_io(struct bio *bio, int err)
+{
+ if (err) {
+ if (err == -EOPNOTSUPP)
+ set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
+ clear_bit(BIO_UPTODATE, &bio->bi_flags);
+ }
+
+ if (bio->bi_private)
+ complete(bio->bi_private);
+ __free_page(bio_page(bio));
+
+ bio_put(bio);
+}
+
+/**
+ * blkdev_issue_discard - queue a discard
+ * @bdev: blockdev to issue discard for
+ * @sector: start sector
+ * @nr_sects: number of sectors to discard
+ * @gfp_mask: memory allocation flags (for bio_alloc)
+ * @flags: BLKDEV_IFL_* flags to control behaviour
+ *
+ * Description:
+ * Issue a discard request for the sectors in question.
+ */
+int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
+ sector_t nr_sects, gfp_t gfp_mask, unsigned long flags)
+{
+ DECLARE_COMPLETION_ONSTACK(wait);
+ struct request_queue *q = bdev_get_queue(bdev);
+ int type = flags & BLKDEV_IFL_BARRIER ?
+ DISCARD_BARRIER : DISCARD_NOBARRIER;
+ struct bio *bio;
+ struct page *page;
+ int ret = 0;
+
+ if (!q)
+ return -ENXIO;
+
+ if (!blk_queue_discard(q))
+ return -EOPNOTSUPP;
+
+ while (nr_sects && !ret) {
+ unsigned int sector_size = q->limits.logical_block_size;
+ unsigned int max_discard_sectors =
+ min(q->limits.max_discard_sectors, UINT_MAX >> 9);
+
+ bio = bio_alloc(gfp_mask, 1);
+ if (!bio)
+ goto out;
+ bio->bi_sector = sector;
+ bio->bi_end_io = blkdev_discard_end_io;
+ bio->bi_bdev = bdev;
+ if (flags & BLKDEV_IFL_WAIT)
+ bio->bi_private = &wait;
+
+ /*
+ * Add a zeroed one-sector payload as that's what
+ * our current implementations need. If we'll ever need
+ * more the interface will need revisiting.
+ */
+ page = alloc_page(gfp_mask | __GFP_ZERO);
+ if (!page)
+ goto out_free_bio;
+ if (bio_add_pc_page(q, bio, page, sector_size, 0) < sector_size)
+ goto out_free_page;
+
+ /*
+ * And override the bio size - the way discard works we
+ * touch many more blocks on disk than the actual payload
+ * length.
+ */
+ if (nr_sects > max_discard_sectors) {
+ bio->bi_size = max_discard_sectors << 9;
+ nr_sects -= max_discard_sectors;
+ sector += max_discard_sectors;
+ } else {
+ bio->bi_size = nr_sects << 9;
+ nr_sects = 0;
+ }
+
+ bio_get(bio);
+ submit_bio(type, bio);
+
+ if (flags & BLKDEV_IFL_WAIT)
+ wait_for_completion(&wait);
+
+ if (bio_flagged(bio, BIO_EOPNOTSUPP))
+ ret = -EOPNOTSUPP;
+ else if (!bio_flagged(bio, BIO_UPTODATE))
+ ret = -EIO;
+ bio_put(bio);
+ }
+ return ret;
+out_free_page:
+ __free_page(page);
+out_free_bio:
+ bio_put(bio);
+out:
+ return -ENOMEM;
+}
+EXPORT_SYMBOL(blkdev_issue_discard);
+
+struct bio_batch
+{
+ atomic_t done;
+ unsigned long flags;
+ struct completion *wait;
+ bio_end_io_t *end_io;
+};
+
+static void bio_batch_end_io(struct bio *bio, int err)
+{
+ struct bio_batch *bb = bio->bi_private;
+
+ if (err) {
+ if (err == -EOPNOTSUPP)
+ set_bit(BIO_EOPNOTSUPP, &bb->flags);
+ else
+ clear_bit(BIO_UPTODATE, &bb->flags);
+ }
+ if (bb) {
+ if (bb->end_io)
+ bb->end_io(bio, err);
+ atomic_inc(&bb->done);
+ complete(bb->wait);
+ }
+ bio_put(bio);
+}
+
+/**
+ * blkdev_issue_zeroout generate number of zero filed write bios
+ * @bdev: blockdev to issue
+ * @sector: start sector
+ * @nr_sects: number of sectors to write
+ * @gfp_mask: memory allocation flags (for bio_alloc)
+ * @flags: BLKDEV_IFL_* flags to control behaviour
+ *
+ * Description:
+ * Generate and issue number of bios with zerofiled pages.
+ * Send barrier at the beginning and at the end if requested. This guarantie
+ * correct request ordering. Empty barrier allow us to avoid post queue flush.
+ */
+
+int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
+ sector_t nr_sects, gfp_t gfp_mask, unsigned long flags)
+{
+ int ret = 0;
+ struct bio *bio;
+ struct bio_batch bb;
+ unsigned int sz, issued = 0;
+ DECLARE_COMPLETION_ONSTACK(wait);
+
+ atomic_set(&bb.done, 0);
+ bb.flags = 1 << BIO_UPTODATE;
+ bb.wait = &wait;
+ bb.end_io = NULL;
+
+ if (flags & BLKDEV_IFL_BARRIER) {
+ /* issue async barrier before the data */
+ ret = blkdev_issue_flush(bdev, gfp_mask, NULL, 0);
+ if (ret)
+ return ret;
+ }
+submit:
+ while (nr_sects != 0) {
+ bio = bio_alloc(gfp_mask,
+ min(nr_sects, (sector_t)BIO_MAX_PAGES));
+ if (!bio)
+ break;
+
+ bio->bi_sector = sector;
+ bio->bi_bdev = bdev;
+ bio->bi_end_io = bio_batch_end_io;
+ if (flags & BLKDEV_IFL_WAIT)
+ bio->bi_private = &bb;
+
+ while (nr_sects != 0) {
+ sz = min((sector_t) PAGE_SIZE >> 9 , nr_sects);
+ if (sz == 0)
+ /* bio has maximum size possible */
+ break;
+ ret = bio_add_page(bio, ZERO_PAGE(0), sz << 9, 0);
+ nr_sects -= ret >> 9;
+ sector += ret >> 9;
+ if (ret < (sz << 9))
+ break;
+ }
+ issued++;
+ submit_bio(WRITE, bio);
+ }
+ /*
+ * When all data bios are in flight. Send final barrier if requeted.
+ */
+ if (nr_sects == 0 && flags & BLKDEV_IFL_BARRIER)
+ ret = blkdev_issue_flush(bdev, gfp_mask, NULL,
+ flags & BLKDEV_IFL_WAIT);
+
+
+ if (flags & BLKDEV_IFL_WAIT)
+ /* Wait for bios in-flight */
+ while ( issued != atomic_read(&bb.done))
+ wait_for_completion(&wait);
+
+ if (!test_bit(BIO_UPTODATE, &bb.flags))
+ /* One of bios in the batch was completed with error.*/
+ ret = -EIO;
+
+ if (ret)
+ goto out;
+
+ if (test_bit(BIO_EOPNOTSUPP, &bb.flags)) {
+ ret = -EOPNOTSUPP;
+ goto out;
+ }
+ if (nr_sects != 0)
+ goto submit;
+out:
+ return ret;
+}
+EXPORT_SYMBOL(blkdev_issue_zeroout);
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 838834b..0f3eb70 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -55,6 +55,7 @@
#define RQ_CIC(rq) \
((struct cfq_io_context *) (rq)->elevator_private)
#define RQ_CFQQ(rq) (struct cfq_queue *) ((rq)->elevator_private2)
+#define RQ_CFQG(rq) (struct cfq_group *) ((rq)->elevator_private3)
static struct kmem_cache *cfq_pool;
static struct kmem_cache *cfq_ioc_pool;
@@ -143,8 +144,6 @@
struct cfq_queue *new_cfqq;
struct cfq_group *cfqg;
struct cfq_group *orig_cfqg;
- /* Sectors dispatched in current dispatch round */
- unsigned long nr_sectors;
};
/*
@@ -346,7 +345,7 @@
CFQ_CFQQ_FNS(wait_busy);
#undef CFQ_CFQQ_FNS
-#ifdef CONFIG_DEBUG_CFQ_IOSCHED
+#ifdef CONFIG_CFQ_GROUP_IOSCHED
#define cfq_log_cfqq(cfqd, cfqq, fmt, args...) \
blk_add_trace_msg((cfqd)->queue, "cfq%d%c %s " fmt, (cfqq)->pid, \
cfq_cfqq_sync((cfqq)) ? 'S' : 'A', \
@@ -858,7 +857,7 @@
if (!RB_EMPTY_NODE(&cfqg->rb_node))
cfq_rb_erase(&cfqg->rb_node, st);
cfqg->saved_workload_slice = 0;
- blkiocg_update_blkio_group_dequeue_stats(&cfqg->blkg, 1);
+ blkiocg_update_dequeue_stats(&cfqg->blkg, 1);
}
static inline unsigned int cfq_cfqq_slice_usage(struct cfq_queue *cfqq)
@@ -884,8 +883,7 @@
slice_used = cfqq->allocated_slice;
}
- cfq_log_cfqq(cfqq->cfqd, cfqq, "sl_used=%u sect=%lu", slice_used,
- cfqq->nr_sectors);
+ cfq_log_cfqq(cfqq->cfqd, cfqq, "sl_used=%u", slice_used);
return slice_used;
}
@@ -919,8 +917,8 @@
cfq_log_cfqg(cfqd, cfqg, "served: vt=%llu min_vt=%llu", cfqg->vdisktime,
st->min_vdisktime);
- blkiocg_update_blkio_group_stats(&cfqg->blkg, used_sl,
- cfqq->nr_sectors);
+ blkiocg_update_timeslice_used(&cfqg->blkg, used_sl);
+ blkiocg_set_start_empty_time(&cfqg->blkg);
}
#ifdef CONFIG_CFQ_GROUP_IOSCHED
@@ -961,7 +959,6 @@
if (!cfqg)
goto done;
- cfqg->weight = blkcg->weight;
for_each_cfqg_st(cfqg, i, j, st)
*st = CFQ_RB_ROOT;
RB_CLEAR_NODE(&cfqg->rb_node);
@@ -978,6 +975,7 @@
sscanf(dev_name(bdi->dev), "%u:%u", &major, &minor);
blkiocg_add_blkio_group(blkcg, &cfqg->blkg, (void *)cfqd,
MKDEV(major, minor));
+ cfqg->weight = blkcg_get_weight(blkcg, cfqg->blkg.dev);
/* Add group on cfqd list */
hlist_add_head(&cfqg->cfqd_node, &cfqd->cfqg_list);
@@ -1004,6 +1002,12 @@
return cfqg;
}
+static inline struct cfq_group *cfq_ref_get_cfqg(struct cfq_group *cfqg)
+{
+ atomic_inc(&cfqg->ref);
+ return cfqg;
+}
+
static void cfq_link_cfqq_cfqg(struct cfq_queue *cfqq, struct cfq_group *cfqg)
{
/* Currently, all async queues are mapped to root group */
@@ -1087,6 +1091,12 @@
{
return &cfqd->root_group;
}
+
+static inline struct cfq_group *cfq_ref_get_cfqg(struct cfq_group *cfqg)
+{
+ return cfqg;
+}
+
static inline void
cfq_link_cfqq_cfqg(struct cfq_queue *cfqq, struct cfq_group *cfqg) {
cfqq->cfqg = cfqg;
@@ -1389,7 +1399,12 @@
{
elv_rb_del(&cfqq->sort_list, rq);
cfqq->queued[rq_is_sync(rq)]--;
+ blkiocg_update_io_remove_stats(&(RQ_CFQG(rq))->blkg, rq_data_dir(rq),
+ rq_is_sync(rq));
cfq_add_rq_rb(rq);
+ blkiocg_update_io_add_stats(&(RQ_CFQG(rq))->blkg,
+ &cfqq->cfqd->serving_group->blkg, rq_data_dir(rq),
+ rq_is_sync(rq));
}
static struct request *
@@ -1445,6 +1460,8 @@
cfq_del_rq_rb(rq);
cfqq->cfqd->rq_queued--;
+ blkiocg_update_io_remove_stats(&(RQ_CFQG(rq))->blkg, rq_data_dir(rq),
+ rq_is_sync(rq));
if (rq_is_meta(rq)) {
WARN_ON(!cfqq->meta_pending);
cfqq->meta_pending--;
@@ -1476,6 +1493,13 @@
}
}
+static void cfq_bio_merged(struct request_queue *q, struct request *req,
+ struct bio *bio)
+{
+ blkiocg_update_io_merged_stats(&(RQ_CFQG(req))->blkg, bio_data_dir(bio),
+ cfq_bio_sync(bio));
+}
+
static void
cfq_merged_requests(struct request_queue *q, struct request *rq,
struct request *next)
@@ -1493,6 +1517,8 @@
if (cfqq->next_rq == next)
cfqq->next_rq = rq;
cfq_remove_request(next);
+ blkiocg_update_io_merged_stats(&(RQ_CFQG(rq))->blkg, rq_data_dir(next),
+ rq_is_sync(next));
}
static int cfq_allow_merge(struct request_queue *q, struct request *rq,
@@ -1520,18 +1546,24 @@
return cfqq == RQ_CFQQ(rq);
}
+static inline void cfq_del_timer(struct cfq_data *cfqd, struct cfq_queue *cfqq)
+{
+ del_timer(&cfqd->idle_slice_timer);
+ blkiocg_update_idle_time_stats(&cfqq->cfqg->blkg);
+}
+
static void __cfq_set_active_queue(struct cfq_data *cfqd,
struct cfq_queue *cfqq)
{
if (cfqq) {
cfq_log_cfqq(cfqd, cfqq, "set_active wl_prio:%d wl_type:%d",
cfqd->serving_prio, cfqd->serving_type);
+ blkiocg_update_avg_queue_size_stats(&cfqq->cfqg->blkg);
cfqq->slice_start = 0;
cfqq->dispatch_start = jiffies;
cfqq->allocated_slice = 0;
cfqq->slice_end = 0;
cfqq->slice_dispatch = 0;
- cfqq->nr_sectors = 0;
cfq_clear_cfqq_wait_request(cfqq);
cfq_clear_cfqq_must_dispatch(cfqq);
@@ -1539,7 +1571,7 @@
cfq_clear_cfqq_fifo_expire(cfqq);
cfq_mark_cfqq_slice_new(cfqq);
- del_timer(&cfqd->idle_slice_timer);
+ cfq_del_timer(cfqd, cfqq);
}
cfqd->active_queue = cfqq;
@@ -1555,7 +1587,7 @@
cfq_log_cfqq(cfqd, cfqq, "slice expired t=%d", timed_out);
if (cfq_cfqq_wait_request(cfqq))
- del_timer(&cfqd->idle_slice_timer);
+ cfq_del_timer(cfqd, cfqq);
cfq_clear_cfqq_wait_request(cfqq);
cfq_clear_cfqq_wait_busy(cfqq);
@@ -1857,6 +1889,7 @@
sl = cfqd->cfq_slice_idle;
mod_timer(&cfqd->idle_slice_timer, jiffies + sl);
+ blkiocg_update_set_idle_time_stats(&cfqq->cfqg->blkg);
cfq_log_cfqq(cfqd, cfqq, "arm_idle: %lu", sl);
}
@@ -1876,7 +1909,8 @@
elv_dispatch_sort(q, rq);
cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]++;
- cfqq->nr_sectors += blk_rq_sectors(rq);
+ blkiocg_update_dispatch_stats(&cfqq->cfqg->blkg, blk_rq_bytes(rq),
+ rq_data_dir(rq), rq_is_sync(rq));
}
/*
@@ -3185,11 +3219,14 @@
if (cfq_cfqq_wait_request(cfqq)) {
if (blk_rq_bytes(rq) > PAGE_CACHE_SIZE ||
cfqd->busy_queues > 1) {
- del_timer(&cfqd->idle_slice_timer);
+ cfq_del_timer(cfqd, cfqq);
cfq_clear_cfqq_wait_request(cfqq);
__blk_run_queue(cfqd->queue);
- } else
+ } else {
+ blkiocg_update_idle_time_stats(
+ &cfqq->cfqg->blkg);
cfq_mark_cfqq_must_dispatch(cfqq);
+ }
}
} else if (cfq_should_preempt(cfqd, cfqq, rq)) {
/*
@@ -3214,7 +3251,9 @@
rq_set_fifo_time(rq, jiffies + cfqd->cfq_fifo_expire[rq_is_sync(rq)]);
list_add_tail(&rq->queuelist, &cfqq->fifo);
cfq_add_rq_rb(rq);
-
+ blkiocg_update_io_add_stats(&(RQ_CFQG(rq))->blkg,
+ &cfqd->serving_group->blkg, rq_data_dir(rq),
+ rq_is_sync(rq));
cfq_rq_enqueued(cfqd, cfqq, rq);
}
@@ -3300,6 +3339,9 @@
WARN_ON(!cfqq->dispatched);
cfqd->rq_in_driver--;
cfqq->dispatched--;
+ blkiocg_update_completion_stats(&cfqq->cfqg->blkg, rq_start_time_ns(rq),
+ rq_io_start_time_ns(rq), rq_data_dir(rq),
+ rq_is_sync(rq));
cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]--;
@@ -3440,6 +3482,10 @@
rq->elevator_private = NULL;
rq->elevator_private2 = NULL;
+ /* Put down rq reference on cfqg */
+ cfq_put_cfqg(RQ_CFQG(rq));
+ rq->elevator_private3 = NULL;
+
cfq_put_queue(cfqq);
}
}
@@ -3528,6 +3574,7 @@
rq->elevator_private = cic;
rq->elevator_private2 = cfqq;
+ rq->elevator_private3 = cfq_ref_get_cfqg(cfqq->cfqg);
return 0;
queue_fail:
@@ -3870,6 +3917,7 @@
.elevator_merged_fn = cfq_merged_request,
.elevator_merge_req_fn = cfq_merged_requests,
.elevator_allow_merge_fn = cfq_allow_merge,
+ .elevator_bio_merged_fn = cfq_bio_merged,
.elevator_dispatch_fn = cfq_dispatch_requests,
.elevator_add_req_fn = cfq_insert_request,
.elevator_activate_req_fn = cfq_activate_request,
diff --git a/block/elevator.c b/block/elevator.c
index 76e3702..5e73459 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -539,6 +539,15 @@
q->last_merge = rq;
}
+void elv_bio_merged(struct request_queue *q, struct request *rq,
+ struct bio *bio)
+{
+ struct elevator_queue *e = q->elevator;
+
+ if (e->ops->elevator_bio_merged_fn)
+ e->ops->elevator_bio_merged_fn(q, rq, bio);
+}
+
void elv_requeue_request(struct request_queue *q, struct request *rq)
{
/*
diff --git a/block/genhd.c b/block/genhd.c
index d13ba76..154b5f8 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -596,6 +596,7 @@
return disk;
}
+EXPORT_SYMBOL(get_gendisk);
/**
* bdget_disk - do bdget() by gendisk and partition number
diff --git a/block/ioctl.c b/block/ioctl.c
index 8905d2a..e8eb679 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -126,7 +126,7 @@
if (start + len > (bdev->bd_inode->i_size >> 9))
return -EINVAL;
return blkdev_issue_discard(bdev, start, len, GFP_KERNEL,
- DISCARD_FL_WAIT);
+ BLKDEV_IFL_WAIT);
}
static int put_ushort(unsigned long arg, unsigned short val)
diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index e5e86a7..d6f1ae3 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -2251,7 +2251,8 @@
if (test_bit(MD_NO_BARRIER, &mdev->flags))
return;
- r = blkdev_issue_flush(mdev->ldev->md_bdev, NULL);
+ r = blkdev_issue_flush(mdev->ldev->md_bdev, GFP_KERNEL, NULL,
+ BLKDEV_IFL_WAIT);
if (r) {
set_bit(MD_NO_BARRIER, &mdev->flags);
dev_err(DEV, "meta data flush failed with status %d, disabling md-flushes\n", r);
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index 3f096e79..c786023 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -946,7 +946,8 @@
int rv;
if (mdev->write_ordering >= WO_bdev_flush && get_ldev(mdev)) {
- rv = blkdev_issue_flush(mdev->ldev->backing_bdev, NULL);
+ rv = blkdev_issue_flush(mdev->ldev->backing_bdev, GFP_KERNEL,
+ NULL, BLKDEV_IFL_WAIT);
if (rv) {
dev_err(DEV, "local disk flush failed with status %d\n", rv);
/* would rather check on EOPNOTSUPP, but that is not reliable.
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 6dcee88..55dcb78 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -417,7 +417,7 @@
*/
mutex_unlock(&bd_inode->i_mutex);
- error = blkdev_issue_flush(bdev, NULL);
+ error = blkdev_issue_flush(bdev, GFP_KERNEL, NULL, BLKDEV_IFL_WAIT);
if (error == -EOPNOTSUPP)
error = 0;
@@ -668,41 +668,209 @@
iput(bdev->bd_inode);
}
-int bd_claim(struct block_device *bdev, void *holder)
+/**
+ * bd_may_claim - test whether a block device can be claimed
+ * @bdev: block device of interest
+ * @whole: whole block device containing @bdev, may equal @bdev
+ * @holder: holder trying to claim @bdev
+ *
+ * Test whther @bdev can be claimed by @holder.
+ *
+ * CONTEXT:
+ * spin_lock(&bdev_lock).
+ *
+ * RETURNS:
+ * %true if @bdev can be claimed, %false otherwise.
+ */
+static bool bd_may_claim(struct block_device *bdev, struct block_device *whole,
+ void *holder)
{
- int res;
+ if (bdev->bd_holder == holder)
+ return true; /* already a holder */
+ else if (bdev->bd_holder != NULL)
+ return false; /* held by someone else */
+ else if (bdev->bd_contains == bdev)
+ return true; /* is a whole device which isn't held */
+
+ else if (whole->bd_holder == bd_claim)
+ return true; /* is a partition of a device that is being partitioned */
+ else if (whole->bd_holder != NULL)
+ return false; /* is a partition of a held device */
+ else
+ return true; /* is a partition of an un-held device */
+}
+
+/**
+ * bd_prepare_to_claim - prepare to claim a block device
+ * @bdev: block device of interest
+ * @whole: the whole device containing @bdev, may equal @bdev
+ * @holder: holder trying to claim @bdev
+ *
+ * Prepare to claim @bdev. This function fails if @bdev is already
+ * claimed by another holder and waits if another claiming is in
+ * progress. This function doesn't actually claim. On successful
+ * return, the caller has ownership of bd_claiming and bd_holder[s].
+ *
+ * CONTEXT:
+ * spin_lock(&bdev_lock). Might release bdev_lock, sleep and regrab
+ * it multiple times.
+ *
+ * RETURNS:
+ * 0 if @bdev can be claimed, -EBUSY otherwise.
+ */
+static int bd_prepare_to_claim(struct block_device *bdev,
+ struct block_device *whole, void *holder)
+{
+retry:
+ /* if someone else claimed, fail */
+ if (!bd_may_claim(bdev, whole, holder))
+ return -EBUSY;
+
+ /* if someone else is claiming, wait for it to finish */
+ if (whole->bd_claiming && whole->bd_claiming != holder) {
+ wait_queue_head_t *wq = bit_waitqueue(&whole->bd_claiming, 0);
+ DEFINE_WAIT(wait);
+
+ prepare_to_wait(wq, &wait, TASK_UNINTERRUPTIBLE);
+ spin_unlock(&bdev_lock);
+ schedule();
+ finish_wait(wq, &wait);
+ spin_lock(&bdev_lock);
+ goto retry;
+ }
+
+ /* yay, all mine */
+ return 0;
+}
+
+/**
+ * bd_start_claiming - start claiming a block device
+ * @bdev: block device of interest
+ * @holder: holder trying to claim @bdev
+ *
+ * @bdev is about to be opened exclusively. Check @bdev can be opened
+ * exclusively and mark that an exclusive open is in progress. Each
+ * successful call to this function must be matched with a call to
+ * either bd_claim() or bd_abort_claiming(). If this function
+ * succeeds, the matching bd_claim() is guaranteed to succeed.
+ *
+ * CONTEXT:
+ * Might sleep.
+ *
+ * RETURNS:
+ * Pointer to the block device containing @bdev on success, ERR_PTR()
+ * value on failure.
+ */
+static struct block_device *bd_start_claiming(struct block_device *bdev,
+ void *holder)
+{
+ struct gendisk *disk;
+ struct block_device *whole;
+ int partno, err;
+
+ might_sleep();
+
+ /*
+ * @bdev might not have been initialized properly yet, look up
+ * and grab the outer block device the hard way.
+ */
+ disk = get_gendisk(bdev->bd_dev, &partno);
+ if (!disk)
+ return ERR_PTR(-ENXIO);
+
+ whole = bdget_disk(disk, 0);
+ put_disk(disk);
+ if (!whole)
+ return ERR_PTR(-ENOMEM);
+
+ /* prepare to claim, if successful, mark claiming in progress */
spin_lock(&bdev_lock);
- /* first decide result */
- if (bdev->bd_holder == holder)
- res = 0; /* already a holder */
- else if (bdev->bd_holder != NULL)
- res = -EBUSY; /* held by someone else */
- else if (bdev->bd_contains == bdev)
- res = 0; /* is a whole device which isn't held */
+ err = bd_prepare_to_claim(bdev, whole, holder);
+ if (err == 0) {
+ whole->bd_claiming = holder;
+ spin_unlock(&bdev_lock);
+ return whole;
+ } else {
+ spin_unlock(&bdev_lock);
+ bdput(whole);
+ return ERR_PTR(err);
+ }
+}
- else if (bdev->bd_contains->bd_holder == bd_claim)
- res = 0; /* is a partition of a device that is being partitioned */
- else if (bdev->bd_contains->bd_holder != NULL)
- res = -EBUSY; /* is a partition of a held device */
- else
- res = 0; /* is a partition of an un-held device */
+/* releases bdev_lock */
+static void __bd_abort_claiming(struct block_device *whole, void *holder)
+{
+ BUG_ON(whole->bd_claiming != holder);
+ whole->bd_claiming = NULL;
+ wake_up_bit(&whole->bd_claiming, 0);
- /* now impose change */
- if (res==0) {
+ spin_unlock(&bdev_lock);
+ bdput(whole);
+}
+
+/**
+ * bd_abort_claiming - abort claiming a block device
+ * @whole: whole block device returned by bd_start_claiming()
+ * @holder: holder trying to claim @bdev
+ *
+ * Abort a claiming block started by bd_start_claiming(). Note that
+ * @whole is not the block device to be claimed but the whole device
+ * returned by bd_start_claiming().
+ *
+ * CONTEXT:
+ * Grabs and releases bdev_lock.
+ */
+static void bd_abort_claiming(struct block_device *whole, void *holder)
+{
+ spin_lock(&bdev_lock);
+ __bd_abort_claiming(whole, holder); /* releases bdev_lock */
+}
+
+/**
+ * bd_claim - claim a block device
+ * @bdev: block device to claim
+ * @holder: holder trying to claim @bdev
+ *
+ * Try to claim @bdev which must have been opened successfully. This
+ * function may be called with or without preceding
+ * blk_start_claiming(). In the former case, this function is always
+ * successful and terminates the claiming block.
+ *
+ * CONTEXT:
+ * Might sleep.
+ *
+ * RETURNS:
+ * 0 if successful, -EBUSY if @bdev is already claimed.
+ */
+int bd_claim(struct block_device *bdev, void *holder)
+{
+ struct block_device *whole = bdev->bd_contains;
+ int res;
+
+ might_sleep();
+
+ spin_lock(&bdev_lock);
+
+ res = bd_prepare_to_claim(bdev, whole, holder);
+ if (res == 0) {
/* note that for a whole device bd_holders
* will be incremented twice, and bd_holder will
* be set to bd_claim before being set to holder
*/
- bdev->bd_contains->bd_holders ++;
- bdev->bd_contains->bd_holder = bd_claim;
+ whole->bd_holders++;
+ whole->bd_holder = bd_claim;
bdev->bd_holders++;
bdev->bd_holder = holder;
}
- spin_unlock(&bdev_lock);
+
+ if (whole->bd_claiming)
+ __bd_abort_claiming(whole, holder); /* releases bdev_lock */
+ else
+ spin_unlock(&bdev_lock);
+
return res;
}
-
EXPORT_SYMBOL(bd_claim);
void bd_release(struct block_device *bdev)
@@ -1316,6 +1484,7 @@
static int blkdev_open(struct inode * inode, struct file * filp)
{
+ struct block_device *whole = NULL;
struct block_device *bdev;
int res;
@@ -1338,22 +1507,25 @@
if (bdev == NULL)
return -ENOMEM;
+ if (filp->f_mode & FMODE_EXCL) {
+ whole = bd_start_claiming(bdev, filp);
+ if (IS_ERR(whole)) {
+ bdput(bdev);
+ return PTR_ERR(whole);
+ }
+ }
+
filp->f_mapping = bdev->bd_inode->i_mapping;
res = blkdev_get(bdev, filp->f_mode);
- if (res)
- return res;
- if (filp->f_mode & FMODE_EXCL) {
- res = bd_claim(bdev, filp);
- if (res)
- goto out_blkdev_put;
+ if (whole) {
+ if (res == 0)
+ BUG_ON(bd_claim(bdev, filp) != 0);
+ else
+ bd_abort_claiming(whole, filp);
}
- return 0;
-
- out_blkdev_put:
- blkdev_put(bdev, filp->f_mode);
return res;
}
@@ -1564,27 +1736,34 @@
*/
struct block_device *open_bdev_exclusive(const char *path, fmode_t mode, void *holder)
{
- struct block_device *bdev;
- int error = 0;
+ struct block_device *bdev, *whole;
+ int error;
bdev = lookup_bdev(path);
if (IS_ERR(bdev))
return bdev;
+ whole = bd_start_claiming(bdev, holder);
+ if (IS_ERR(whole)) {
+ bdput(bdev);
+ return whole;
+ }
+
error = blkdev_get(bdev, mode);
if (error)
- return ERR_PTR(error);
+ goto out_abort_claiming;
+
error = -EACCES;
if ((mode & FMODE_WRITE) && bdev_read_only(bdev))
- goto blkdev_put;
- error = bd_claim(bdev, holder);
- if (error)
- goto blkdev_put;
+ goto out_blkdev_put;
+ BUG_ON(bd_claim(bdev, holder) != 0);
return bdev;
-
-blkdev_put:
+
+out_blkdev_put:
blkdev_put(bdev, mode);
+out_abort_claiming:
+ bd_abort_claiming(whole, holder);
return ERR_PTR(error);
}
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index b34d32f..c6a4f45 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -1589,7 +1589,7 @@
u64 start, u64 len)
{
blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL,
- DISCARD_FL_BARRIER);
+ BLKDEV_IFL_WAIT | BLKDEV_IFL_BARRIER);
}
static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
diff --git a/fs/ext3/fsync.c b/fs/ext3/fsync.c
index 8209f26..9492f60 100644
--- a/fs/ext3/fsync.c
+++ b/fs/ext3/fsync.c
@@ -91,7 +91,8 @@
* storage
*/
if (test_opt(inode->i_sb, BARRIER))
- blkdev_issue_flush(inode->i_sb->s_bdev, NULL);
+ blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL,
+ BLKDEV_IFL_WAIT);
out:
return ret;
}
diff --git a/fs/ext4/fsync.c b/fs/ext4/fsync.c
index 0d0c323..ef3d980 100644
--- a/fs/ext4/fsync.c
+++ b/fs/ext4/fsync.c
@@ -100,9 +100,11 @@
if (ext4_should_writeback_data(inode) &&
(journal->j_fs_dev != journal->j_dev) &&
(journal->j_flags & JBD2_BARRIER))
- blkdev_issue_flush(inode->i_sb->s_bdev, NULL);
+ blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL,
+ NULL, BLKDEV_IFL_WAIT);
jbd2_log_wait_commit(journal, commit_tid);
} else if (journal->j_flags & JBD2_BARRIER)
- blkdev_issue_flush(inode->i_sb->s_bdev, NULL);
+ blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL,
+ BLKDEV_IFL_WAIT);
return ret;
}
diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c
index 503b842..bf011dc 100644
--- a/fs/gfs2/rgrp.c
+++ b/fs/gfs2/rgrp.c
@@ -854,7 +854,8 @@
if ((start + nr_sects) != blk) {
rv = blkdev_issue_discard(bdev, start,
nr_sects, GFP_NOFS,
- DISCARD_FL_BARRIER);
+ BLKDEV_IFL_WAIT |
+ BLKDEV_IFL_BARRIER);
if (rv)
goto fail;
nr_sects = 0;
@@ -869,7 +870,7 @@
}
if (nr_sects) {
rv = blkdev_issue_discard(bdev, start, nr_sects, GFP_NOFS,
- DISCARD_FL_BARRIER);
+ BLKDEV_IFL_WAIT | BLKDEV_IFL_BARRIER);
if (rv)
goto fail;
}
diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c
index 30beb11..076d1cc 100644
--- a/fs/jbd2/checkpoint.c
+++ b/fs/jbd2/checkpoint.c
@@ -530,7 +530,8 @@
*/
if ((journal->j_fs_dev != journal->j_dev) &&
(journal->j_flags & JBD2_BARRIER))
- blkdev_issue_flush(journal->j_fs_dev, NULL);
+ blkdev_issue_flush(journal->j_fs_dev, GFP_KERNEL, NULL,
+ BLKDEV_IFL_WAIT);
if (!(journal->j_flags & JBD2_ABORT))
jbd2_journal_update_superblock(journal, 1);
return 0;
diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index 671da7f..75716d3 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -717,7 +717,8 @@
if (commit_transaction->t_flushed_data_blocks &&
(journal->j_fs_dev != journal->j_dev) &&
(journal->j_flags & JBD2_BARRIER))
- blkdev_issue_flush(journal->j_fs_dev, NULL);
+ blkdev_issue_flush(journal->j_fs_dev, GFP_KERNEL, NULL,
+ BLKDEV_IFL_WAIT);
/* Done it all: now write the commit record asynchronously. */
if (JBD2_HAS_INCOMPAT_FEATURE(journal,
@@ -727,7 +728,8 @@
if (err)
__jbd2_journal_abort_hard(journal);
if (journal->j_flags & JBD2_BARRIER)
- blkdev_issue_flush(journal->j_dev, NULL);
+ blkdev_issue_flush(journal->j_dev, GFP_KERNEL, NULL,
+ BLKDEV_IFL_WAIT);
}
err = journal_finish_inode_data_buffers(journal, commit_transaction);
diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c
index 33871f7..7ffcf2b 100644
--- a/fs/nilfs2/the_nilfs.c
+++ b/fs/nilfs2/the_nilfs.c
@@ -670,7 +670,7 @@
start * sects_per_block,
nblocks * sects_per_block,
GFP_NOFS,
- DISCARD_FL_BARRIER);
+ BLKDEV_IFL_BARRIER);
if (ret < 0)
return ret;
nblocks = 0;
@@ -680,7 +680,7 @@
ret = blkdev_issue_discard(nilfs->ns_bdev,
start * sects_per_block,
nblocks * sects_per_block,
- GFP_NOFS, DISCARD_FL_BARRIER);
+ GFP_NOFS, BLKDEV_IFL_BARRIER);
return ret;
}
diff --git a/fs/reiserfs/file.c b/fs/reiserfs/file.c
index 1d9c127..9977df9 100644
--- a/fs/reiserfs/file.c
+++ b/fs/reiserfs/file.c
@@ -147,7 +147,8 @@
barrier_done = reiserfs_commit_for_inode(inode);
reiserfs_write_unlock(inode->i_sb);
if (barrier_done != 1 && reiserfs_barrier_flush(inode->i_sb))
- blkdev_issue_flush(inode->i_sb->s_bdev, NULL);
+ blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL,
+ BLKDEV_IFL_WAIT);
if (barrier_done < 0)
return barrier_done;
return (err < 0) ? -EIO : 0;
diff --git a/fs/xfs/linux-2.6/xfs_super.c b/fs/xfs/linux-2.6/xfs_super.c
index 52e06b4..2b177c7 100644
--- a/fs/xfs/linux-2.6/xfs_super.c
+++ b/fs/xfs/linux-2.6/xfs_super.c
@@ -725,7 +725,8 @@
xfs_blkdev_issue_flush(
xfs_buftarg_t *buftarg)
{
- blkdev_issue_flush(buftarg->bt_bdev, NULL);
+ blkdev_issue_flush(buftarg->bt_bdev, GFP_KERNEL, NULL,
+ BLKDEV_IFL_WAIT);
}
STATIC void
diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index bd0e3c6..7534979 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -14,6 +14,7 @@
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/sched.h>
+#include <linux/timer.h>
#include <linux/writeback.h>
#include <asm/atomic.h>
@@ -88,6 +89,8 @@
struct device *dev;
+ struct timer_list laptop_mode_wb_timer;
+
#ifdef CONFIG_DEBUG_FS
struct dentry *debug_dir;
struct dentry *debug_stats;
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 6690e8b..3ac2bd2 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -186,15 +186,19 @@
};
/*
- * two pointers are available for the IO schedulers, if they need
+ * Three pointers are available for the IO schedulers, if they need
* more they have to dynamically allocate it.
*/
void *elevator_private;
void *elevator_private2;
+ void *elevator_private3;
struct gendisk *rq_disk;
unsigned long start_time;
-
+#ifdef CONFIG_BLK_CGROUP
+ unsigned long long start_time_ns;
+ unsigned long long io_start_time_ns; /* when passed to hardware */
+#endif
/* Number of scatter-gather DMA addr+len pairs after
* physical address coalescing is performed.
*/
@@ -994,20 +998,25 @@
return NULL;
return bqt->tag_index[tag];
}
-
-extern int blkdev_issue_flush(struct block_device *, sector_t *);
-#define DISCARD_FL_WAIT 0x01 /* wait for completion */
-#define DISCARD_FL_BARRIER 0x02 /* issue DISCARD_BARRIER request */
-extern int blkdev_issue_discard(struct block_device *, sector_t sector,
- sector_t nr_sects, gfp_t, int flags);
-
+enum{
+ BLKDEV_WAIT, /* wait for completion */
+ BLKDEV_BARRIER, /*issue request with barrier */
+};
+#define BLKDEV_IFL_WAIT (1 << BLKDEV_WAIT)
+#define BLKDEV_IFL_BARRIER (1 << BLKDEV_BARRIER)
+extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *,
+ unsigned long);
+extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
+ sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
+extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
+ sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
static inline int sb_issue_discard(struct super_block *sb,
sector_t block, sector_t nr_blocks)
{
block <<= (sb->s_blocksize_bits - 9);
nr_blocks <<= (sb->s_blocksize_bits - 9);
return blkdev_issue_discard(sb->s_bdev, block, nr_blocks, GFP_KERNEL,
- DISCARD_FL_BARRIER);
+ BLKDEV_IFL_WAIT | BLKDEV_IFL_BARRIER);
}
extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
@@ -1196,6 +1205,39 @@
struct work_struct;
int kblockd_schedule_work(struct request_queue *q, struct work_struct *work);
+#ifdef CONFIG_BLK_CGROUP
+static inline void set_start_time_ns(struct request *req)
+{
+ req->start_time_ns = sched_clock();
+}
+
+static inline void set_io_start_time_ns(struct request *req)
+{
+ req->io_start_time_ns = sched_clock();
+}
+
+static inline uint64_t rq_start_time_ns(struct request *req)
+{
+ return req->start_time_ns;
+}
+
+static inline uint64_t rq_io_start_time_ns(struct request *req)
+{
+ return req->io_start_time_ns;
+}
+#else
+static inline void set_start_time_ns(struct request *req) {}
+static inline void set_io_start_time_ns(struct request *req) {}
+static inline uint64_t rq_start_time_ns(struct request *req)
+{
+ return 0;
+}
+static inline uint64_t rq_io_start_time_ns(struct request *req)
+{
+ return 0;
+}
+#endif
+
#define MODULE_ALIAS_BLOCKDEV(major,minor) \
MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
#define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
diff --git a/include/linux/elevator.h b/include/linux/elevator.h
index 1cb3372e..2c958f4 100644
--- a/include/linux/elevator.h
+++ b/include/linux/elevator.h
@@ -14,6 +14,9 @@
typedef int (elevator_allow_merge_fn) (struct request_queue *, struct request *, struct bio *);
+typedef void (elevator_bio_merged_fn) (struct request_queue *,
+ struct request *, struct bio *);
+
typedef int (elevator_dispatch_fn) (struct request_queue *, int);
typedef void (elevator_add_req_fn) (struct request_queue *, struct request *);
@@ -36,6 +39,7 @@
elevator_merged_fn *elevator_merged_fn;
elevator_merge_req_fn *elevator_merge_req_fn;
elevator_allow_merge_fn *elevator_allow_merge_fn;
+ elevator_bio_merged_fn *elevator_bio_merged_fn;
elevator_dispatch_fn *elevator_dispatch_fn;
elevator_add_req_fn *elevator_add_req_fn;
@@ -103,6 +107,8 @@
extern void elv_merge_requests(struct request_queue *, struct request *,
struct request *);
extern void elv_merged_request(struct request_queue *, struct request *, int);
+extern void elv_bio_merged(struct request_queue *q, struct request *,
+ struct bio *);
extern void elv_requeue_request(struct request_queue *, struct request *);
extern int elv_queue_empty(struct request_queue *);
extern struct request *elv_former_request(struct request_queue *, struct request *);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 44f35ae..f30970c 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -651,6 +651,7 @@
int bd_openers;
struct mutex bd_mutex; /* open/close mutex */
struct list_head bd_inodes;
+ void * bd_claiming;
void * bd_holder;
int bd_holders;
#ifdef CONFIG_SYSFS
diff --git a/include/linux/writeback.h b/include/linux/writeback.h
index 36520de..eb38a2c 100644
--- a/include/linux/writeback.h
+++ b/include/linux/writeback.h
@@ -96,8 +96,10 @@
/*
* mm/page-writeback.c
*/
-void laptop_io_completion(void);
+void laptop_io_completion(struct backing_dev_info *info);
void laptop_sync_completion(void);
+void laptop_mode_sync(struct work_struct *work);
+void laptop_mode_timer_fn(unsigned long data);
void throttle_vm_writeout(gfp_t gfp_mask);
/* These are exported to sysctl. */
diff --git a/init/Kconfig b/init/Kconfig
index eb77e8c..087c14f 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -612,6 +612,33 @@
endif #CGROUP_SCHED
+config BLK_CGROUP
+ tristate "Block IO controller"
+ depends on CGROUPS && BLOCK
+ default n
+ ---help---
+ Generic block IO controller cgroup interface. This is the common
+ cgroup interface which should be used by various IO controlling
+ policies.
+
+ Currently, CFQ IO scheduler uses it to recognize task groups and
+ control disk bandwidth allocation (proportional time slice allocation)
+ to such task groups.
+
+ This option only enables generic Block IO controller infrastructure.
+ One needs to also enable actual IO controlling logic in CFQ for it
+ to take effect. (CONFIG_CFQ_GROUP_IOSCHED=y).
+
+ See Documentation/cgroups/blkio-controller.txt for more information.
+
+config DEBUG_BLK_CGROUP
+ bool "Enable Block IO controller debugging"
+ depends on BLK_CGROUP
+ default n
+ ---help---
+ Enable some debugging help. Currently it exports additional stat
+ files in a cgroup which can be useful for debugging.
+
endif # CGROUPS
config MM_OWNER
diff --git a/kernel/sched_clock.c b/kernel/sched_clock.c
index 5b49613..906a0f7 100644
--- a/kernel/sched_clock.c
+++ b/kernel/sched_clock.c
@@ -41,6 +41,7 @@
return (unsigned long long)(jiffies - INITIAL_JIFFIES)
* (NSEC_PER_SEC / HZ);
}
+EXPORT_SYMBOL_GPL(sched_clock);
static __read_mostly int sched_clock_running;
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 0b19943..d0f2b37 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -683,10 +683,6 @@
}
}
-static void laptop_timer_fn(unsigned long unused);
-
-static DEFINE_TIMER(laptop_mode_wb_timer, laptop_timer_fn, 0, 0);
-
/*
* sysctl handler for /proc/sys/vm/dirty_writeback_centisecs
*/
@@ -697,21 +693,19 @@
return 0;
}
-static void do_laptop_sync(struct work_struct *work)
+void laptop_mode_timer_fn(unsigned long data)
{
- wakeup_flusher_threads(0);
- kfree(work);
-}
+ struct request_queue *q = (struct request_queue *)data;
+ int nr_pages = global_page_state(NR_FILE_DIRTY) +
+ global_page_state(NR_UNSTABLE_NFS);
-static void laptop_timer_fn(unsigned long unused)
-{
- struct work_struct *work;
+ /*
+ * We want to write everything out, not just down to the dirty
+ * threshold
+ */
- work = kmalloc(sizeof(*work), GFP_ATOMIC);
- if (work) {
- INIT_WORK(work, do_laptop_sync);
- schedule_work(work);
- }
+ if (bdi_has_dirty_io(&q->backing_dev_info))
+ bdi_start_writeback(&q->backing_dev_info, NULL, nr_pages);
}
/*
@@ -719,9 +713,9 @@
* of all dirty data a few seconds from now. If the flush is already scheduled
* then push it back - the user is still using the disk.
*/
-void laptop_io_completion(void)
+void laptop_io_completion(struct backing_dev_info *info)
{
- mod_timer(&laptop_mode_wb_timer, jiffies + laptop_mode);
+ mod_timer(&info->laptop_mode_wb_timer, jiffies + laptop_mode);
}
/*
@@ -731,7 +725,14 @@
*/
void laptop_sync_completion(void)
{
- del_timer(&laptop_mode_wb_timer);
+ struct backing_dev_info *bdi;
+
+ rcu_read_lock();
+
+ list_for_each_entry_rcu(bdi, &bdi_list, bdi_list)
+ del_timer(&bdi->laptop_mode_wb_timer);
+
+ rcu_read_unlock();
}
/*
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 6cd0a8f..eb086e0 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -139,7 +139,8 @@
nr_blocks = ((sector_t)se->nr_pages - 1) << (PAGE_SHIFT - 9);
if (nr_blocks) {
err = blkdev_issue_discard(si->bdev, start_block,
- nr_blocks, GFP_KERNEL, DISCARD_FL_BARRIER);
+ nr_blocks, GFP_KERNEL,
+ BLKDEV_IFL_WAIT | BLKDEV_IFL_BARRIER);
if (err)
return err;
cond_resched();
@@ -150,7 +151,8 @@
nr_blocks = (sector_t)se->nr_pages << (PAGE_SHIFT - 9);
err = blkdev_issue_discard(si->bdev, start_block,
- nr_blocks, GFP_KERNEL, DISCARD_FL_BARRIER);
+ nr_blocks, GFP_KERNEL,
+ BLKDEV_IFL_WAIT | BLKDEV_IFL_BARRIER);
if (err)
break;
@@ -189,7 +191,8 @@
start_block <<= PAGE_SHIFT - 9;
nr_blocks <<= PAGE_SHIFT - 9;
if (blkdev_issue_discard(si->bdev, start_block,
- nr_blocks, GFP_NOIO, DISCARD_FL_BARRIER))
+ nr_blocks, GFP_NOIO, BLKDEV_IFL_WAIT |
+ BLKDEV_IFL_BARRIER))
break;
}