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authorLinus Torvalds <torvalds@linux-foundation.org>2010-10-22 17:00:32 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-10-22 17:00:32 -0700
commite9dd2b6837e26fe202708cce5ea4bb4ee3e3482e (patch)
treef42fd892495bfc4cbb740d06b016d267c9c42d00 /block
parent4f3a29dadaf999a273f1e7fe2476595d0283eef3 (diff)
parentb4627321e18582dcbdeb45d77df29d3177107c65 (diff)
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Merge branch 'for-2.6.37/core' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.37/core' of git://git.kernel.dk/linux-2.6-block: (39 commits) cfq-iosched: Fix a gcc 4.5 warning and put some comments block: Turn bvec_k{un,}map_irq() into static inline functions block: fix accounting bug on cross partition merges block: Make the integrity mapped property a bio flag block: Fix double free in blk_integrity_unregister block: Ensure physical block size is unsigned int blkio-throttle: Fix possible multiplication overflow in iops calculations blkio-throttle: limit max iops value to UINT_MAX blkio-throttle: There is no need to convert jiffies to milli seconds blkio-throttle: Fix link failure failure on i386 blkio: Recalculate the throttled bio dispatch time upon throttle limit change blkio: Add root group to td->tg_list blkio: deletion of a cgroup was causes oops blkio: Do not export throttle files if CONFIG_BLK_DEV_THROTTLING=n block: set the bounce_pfn to the actual DMA limit rather than to max memory block: revert bad fix for memory hotplug causing bounces Fix compile error in blk-exec.c for !CONFIG_DETECT_HUNG_TASK block: set the bounce_pfn to the actual DMA limit rather than to max memory block: Prevent hang_check firing during long I/O cfq: improve fsync performance for small files ... Fix up trivial conflicts due to __rcu sparse annotation in include/linux/genhd.h
Diffstat (limited to 'block')
-rw-r--r--block/Kconfig12
-rw-r--r--block/Makefile1
-rw-r--r--block/blk-cgroup.c804
-rw-r--r--block/blk-cgroup.h87
-rw-r--r--block/blk-core.c53
-rw-r--r--block/blk-exec.c9
-rw-r--r--block/blk-integrity.c94
-rw-r--r--block/blk-map.c5
-rw-r--r--block/blk-merge.c25
-rw-r--r--block/blk-settings.c12
-rw-r--r--block/blk-sysfs.c11
-rw-r--r--block/blk-throttle.c1123
-rw-r--r--block/blk.h12
-rw-r--r--block/cfq-iosched.c39
-rw-r--r--block/cfq.h2
-rw-r--r--block/genhd.c30
-rw-r--r--block/ioctl.c2
17 files changed, 2069 insertions, 252 deletions
diff --git a/block/Kconfig b/block/Kconfig
index 9be0b56eaee..6c9213ef15a 100644
--- a/block/Kconfig
+++ b/block/Kconfig
@@ -77,6 +77,18 @@ config BLK_DEV_INTEGRITY
T10/SCSI Data Integrity Field or the T13/ATA External Path
Protection. If in doubt, say N.
+config BLK_DEV_THROTTLING
+ bool "Block layer bio throttling support"
+ depends on BLK_CGROUP=y && EXPERIMENTAL
+ default n
+ ---help---
+ Block layer bio throttling support. It can be used to limit
+ the IO rate to a device. IO rate policies are per cgroup and
+ one needs to mount and use blkio cgroup controller for creating
+ cgroups and specifying per device IO rate policies.
+
+ See Documentation/cgroups/blkio-controller.txt for more information.
+
endif # BLOCK
config BLOCK_COMPAT
diff --git a/block/Makefile b/block/Makefile
index 0bb499a739c..c850d5ef80a 100644
--- a/block/Makefile
+++ b/block/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_BLOCK) := elevator.o blk-core.o blk-tag.o blk-sysfs.o \
obj-$(CONFIG_BLK_DEV_BSG) += bsg.o
obj-$(CONFIG_BLK_CGROUP) += blk-cgroup.o
+obj-$(CONFIG_BLK_DEV_THROTTLING) += blk-throttle.o
obj-$(CONFIG_IOSCHED_NOOP) += noop-iosched.o
obj-$(CONFIG_IOSCHED_DEADLINE) += deadline-iosched.o
obj-$(CONFIG_IOSCHED_CFQ) += cfq-iosched.o
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 2fef1ef931a..b1febd0f6d2 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -37,6 +37,12 @@ static void blkiocg_attach(struct cgroup_subsys *, struct cgroup *,
static void blkiocg_destroy(struct cgroup_subsys *, struct cgroup *);
static int blkiocg_populate(struct cgroup_subsys *, struct cgroup *);
+/* for encoding cft->private value on file */
+#define BLKIOFILE_PRIVATE(x, val) (((x) << 16) | (val))
+/* What policy owns the file, proportional or throttle */
+#define BLKIOFILE_POLICY(val) (((val) >> 16) & 0xffff)
+#define BLKIOFILE_ATTR(val) ((val) & 0xffff)
+
struct cgroup_subsys blkio_subsys = {
.name = "blkio",
.create = blkiocg_create,
@@ -59,6 +65,27 @@ static inline void blkio_policy_insert_node(struct blkio_cgroup *blkcg,
list_add(&pn->node, &blkcg->policy_list);
}
+static inline bool cftype_blkg_same_policy(struct cftype *cft,
+ struct blkio_group *blkg)
+{
+ enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private);
+
+ if (blkg->plid == plid)
+ return 1;
+
+ return 0;
+}
+
+/* Determines if policy node matches cgroup file being accessed */
+static inline bool pn_matches_cftype(struct cftype *cft,
+ struct blkio_policy_node *pn)
+{
+ enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private);
+ int fileid = BLKIOFILE_ATTR(cft->private);
+
+ return (plid == pn->plid && fileid == pn->fileid);
+}
+
/* Must be called with blkcg->lock held */
static inline void blkio_policy_delete_node(struct blkio_policy_node *pn)
{
@@ -67,12 +94,13 @@ static inline void blkio_policy_delete_node(struct blkio_policy_node *pn)
/* Must be called with blkcg->lock held */
static struct blkio_policy_node *
-blkio_policy_search_node(const struct blkio_cgroup *blkcg, dev_t dev)
+blkio_policy_search_node(const struct blkio_cgroup *blkcg, dev_t dev,
+ enum blkio_policy_id plid, int fileid)
{
struct blkio_policy_node *pn;
list_for_each_entry(pn, &blkcg->policy_list, node) {
- if (pn->dev == dev)
+ if (pn->dev == dev && pn->plid == plid && pn->fileid == fileid)
return pn;
}
@@ -86,6 +114,67 @@ struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup)
}
EXPORT_SYMBOL_GPL(cgroup_to_blkio_cgroup);
+static inline void
+blkio_update_group_weight(struct blkio_group *blkg, unsigned int weight)
+{
+ struct blkio_policy_type *blkiop;
+
+ list_for_each_entry(blkiop, &blkio_list, list) {
+ /* If this policy does not own the blkg, do not send updates */
+ if (blkiop->plid != blkg->plid)
+ continue;
+ if (blkiop->ops.blkio_update_group_weight_fn)
+ blkiop->ops.blkio_update_group_weight_fn(blkg->key,
+ blkg, weight);
+ }
+}
+
+static inline void blkio_update_group_bps(struct blkio_group *blkg, u64 bps,
+ int fileid)
+{
+ struct blkio_policy_type *blkiop;
+
+ list_for_each_entry(blkiop, &blkio_list, list) {
+
+ /* If this policy does not own the blkg, do not send updates */
+ if (blkiop->plid != blkg->plid)
+ continue;
+
+ if (fileid == BLKIO_THROTL_read_bps_device
+ && blkiop->ops.blkio_update_group_read_bps_fn)
+ blkiop->ops.blkio_update_group_read_bps_fn(blkg->key,
+ blkg, bps);
+
+ if (fileid == BLKIO_THROTL_write_bps_device
+ && blkiop->ops.blkio_update_group_write_bps_fn)
+ blkiop->ops.blkio_update_group_write_bps_fn(blkg->key,
+ blkg, bps);
+ }
+}
+
+static inline void blkio_update_group_iops(struct blkio_group *blkg,
+ unsigned int iops, int fileid)
+{
+ struct blkio_policy_type *blkiop;
+
+ list_for_each_entry(blkiop, &blkio_list, list) {
+
+ /* If this policy does not own the blkg, do not send updates */
+ if (blkiop->plid != blkg->plid)
+ continue;
+
+ if (fileid == BLKIO_THROTL_read_iops_device
+ && blkiop->ops.blkio_update_group_read_iops_fn)
+ blkiop->ops.blkio_update_group_read_iops_fn(blkg->key,
+ blkg, iops);
+
+ if (fileid == BLKIO_THROTL_write_iops_device
+ && blkiop->ops.blkio_update_group_write_iops_fn)
+ blkiop->ops.blkio_update_group_write_iops_fn(blkg->key,
+ blkg,iops);
+ }
+}
+
/*
* Add to the appropriate stat variable depending on the request type.
* This should be called with the blkg->stats_lock held.
@@ -341,7 +430,8 @@ void blkiocg_update_io_merged_stats(struct blkio_group *blkg, bool direction,
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)
+ struct blkio_group *blkg, void *key, dev_t dev,
+ enum blkio_policy_id plid)
{
unsigned long flags;
@@ -350,6 +440,7 @@ void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
rcu_assign_pointer(blkg->key, key);
blkg->blkcg_id = css_id(&blkcg->css);
hlist_add_head_rcu(&blkg->blkcg_node, &blkcg->blkg_list);
+ blkg->plid = plid;
spin_unlock_irqrestore(&blkcg->lock, flags);
/* Need to take css reference ? */
cgroup_path(blkcg->css.cgroup, blkg->path, sizeof(blkg->path));
@@ -408,51 +499,6 @@ struct blkio_group *blkiocg_lookup_group(struct blkio_cgroup *blkcg, void *key)
}
EXPORT_SYMBOL_GPL(blkiocg_lookup_group);
-#define SHOW_FUNCTION(__VAR) \
-static u64 blkiocg_##__VAR##_read(struct cgroup *cgroup, \
- struct cftype *cftype) \
-{ \
- struct blkio_cgroup *blkcg; \
- \
- blkcg = cgroup_to_blkio_cgroup(cgroup); \
- return (u64)blkcg->__VAR; \
-}
-
-SHOW_FUNCTION(weight);
-#undef SHOW_FUNCTION
-
-static int
-blkiocg_weight_write(struct cgroup *cgroup, struct cftype *cftype, u64 val)
-{
- struct blkio_cgroup *blkcg;
- 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;
-
- blkcg = cgroup_to_blkio_cgroup(cgroup);
- 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);
- }
- spin_unlock_irq(&blkcg->lock);
- spin_unlock(&blkio_list_lock);
- return 0;
-}
-
static int
blkiocg_reset_stats(struct cgroup *cgroup, struct cftype *cftype, u64 val)
{
@@ -593,52 +639,6 @@ static uint64_t blkio_get_stat(struct blkio_group *blkg,
return disk_total;
}
-#define SHOW_FUNCTION_PER_GROUP(__VAR, type, show_total) \
-static int blkiocg_##__VAR##_read(struct cgroup *cgroup, \
- 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; \
- \
- blkcg = cgroup_to_blkio_cgroup(cgroup); \
- rcu_read_lock(); \
- hlist_for_each_entry_rcu(blkg, n, &blkcg->blkg_list, blkcg_node) {\
- 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, 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, 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
-
static int blkio_check_dev_num(dev_t dev)
{
int part = 0;
@@ -652,13 +652,14 @@ static int blkio_check_dev_num(dev_t dev)
}
static int blkio_policy_parse_and_set(char *buf,
- struct blkio_policy_node *newpn)
+ struct blkio_policy_node *newpn, enum blkio_policy_id plid, int fileid)
{
char *s[4], *p, *major_s = NULL, *minor_s = NULL;
int ret;
unsigned long major, minor, temp;
int i = 0;
dev_t dev;
+ u64 bps, iops;
memset(s, 0, sizeof(s));
@@ -705,12 +706,47 @@ static int blkio_policy_parse_and_set(char *buf,
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;
+ switch (plid) {
+ case BLKIO_POLICY_PROP:
+ ret = strict_strtoul(s[1], 10, &temp);
+ if (ret || (temp < BLKIO_WEIGHT_MIN && temp > 0) ||
+ temp > BLKIO_WEIGHT_MAX)
+ return -EINVAL;
- newpn->weight = temp;
+ newpn->plid = plid;
+ newpn->fileid = fileid;
+ newpn->val.weight = temp;
+ break;
+ case BLKIO_POLICY_THROTL:
+ switch(fileid) {
+ case BLKIO_THROTL_read_bps_device:
+ case BLKIO_THROTL_write_bps_device:
+ ret = strict_strtoull(s[1], 10, &bps);
+ if (ret)
+ return -EINVAL;
+
+ newpn->plid = plid;
+ newpn->fileid = fileid;
+ newpn->val.bps = bps;
+ break;
+ case BLKIO_THROTL_read_iops_device:
+ case BLKIO_THROTL_write_iops_device:
+ ret = strict_strtoull(s[1], 10, &iops);
+ if (ret)
+ return -EINVAL;
+
+ if (iops > THROTL_IOPS_MAX)
+ return -EINVAL;
+
+ newpn->plid = plid;
+ newpn->fileid = fileid;
+ newpn->val.iops = (unsigned int)iops;
+ break;
+ }
+ break;
+ default:
+ BUG();
+ }
return 0;
}
@@ -720,26 +756,180 @@ unsigned int blkcg_get_weight(struct blkio_cgroup *blkcg,
{
struct blkio_policy_node *pn;
- pn = blkio_policy_search_node(blkcg, dev);
+ pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_PROP,
+ BLKIO_PROP_weight_device);
if (pn)
- return pn->weight;
+ return pn->val.weight;
else
return blkcg->weight;
}
EXPORT_SYMBOL_GPL(blkcg_get_weight);
+uint64_t blkcg_get_read_bps(struct blkio_cgroup *blkcg, dev_t dev)
+{
+ struct blkio_policy_node *pn;
+
+ pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL,
+ BLKIO_THROTL_read_bps_device);
+ if (pn)
+ return pn->val.bps;
+ else
+ return -1;
+}
+
+uint64_t blkcg_get_write_bps(struct blkio_cgroup *blkcg, dev_t dev)
+{
+ struct blkio_policy_node *pn;
+ pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL,
+ BLKIO_THROTL_write_bps_device);
+ if (pn)
+ return pn->val.bps;
+ else
+ return -1;
+}
+
+unsigned int blkcg_get_read_iops(struct blkio_cgroup *blkcg, dev_t dev)
+{
+ struct blkio_policy_node *pn;
+
+ pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL,
+ BLKIO_THROTL_read_iops_device);
+ if (pn)
+ return pn->val.iops;
+ else
+ return -1;
+}
+
+unsigned int blkcg_get_write_iops(struct blkio_cgroup *blkcg, dev_t dev)
+{
+ struct blkio_policy_node *pn;
+ pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL,
+ BLKIO_THROTL_write_iops_device);
+ if (pn)
+ return pn->val.iops;
+ else
+ return -1;
+}
+
+/* Checks whether user asked for deleting a policy rule */
+static bool blkio_delete_rule_command(struct blkio_policy_node *pn)
+{
+ switch(pn->plid) {
+ case BLKIO_POLICY_PROP:
+ if (pn->val.weight == 0)
+ return 1;
+ break;
+ case BLKIO_POLICY_THROTL:
+ switch(pn->fileid) {
+ case BLKIO_THROTL_read_bps_device:
+ case BLKIO_THROTL_write_bps_device:
+ if (pn->val.bps == 0)
+ return 1;
+ break;
+ case BLKIO_THROTL_read_iops_device:
+ case BLKIO_THROTL_write_iops_device:
+ if (pn->val.iops == 0)
+ return 1;
+ }
+ break;
+ default:
+ BUG();
+ }
+
+ return 0;
+}
+
+static void blkio_update_policy_rule(struct blkio_policy_node *oldpn,
+ struct blkio_policy_node *newpn)
+{
+ switch(oldpn->plid) {
+ case BLKIO_POLICY_PROP:
+ oldpn->val.weight = newpn->val.weight;
+ break;
+ case BLKIO_POLICY_THROTL:
+ switch(newpn->fileid) {
+ case BLKIO_THROTL_read_bps_device:
+ case BLKIO_THROTL_write_bps_device:
+ oldpn->val.bps = newpn->val.bps;
+ break;
+ case BLKIO_THROTL_read_iops_device:
+ case BLKIO_THROTL_write_iops_device:
+ oldpn->val.iops = newpn->val.iops;
+ }
+ break;
+ default:
+ BUG();
+ }
+}
+
+/*
+ * Some rules/values in blkg have changed. Propogate those to respective
+ * policies.
+ */
+static void blkio_update_blkg_policy(struct blkio_cgroup *blkcg,
+ struct blkio_group *blkg, struct blkio_policy_node *pn)
+{
+ unsigned int weight, iops;
+ u64 bps;
+
+ switch(pn->plid) {
+ case BLKIO_POLICY_PROP:
+ weight = pn->val.weight ? pn->val.weight :
+ blkcg->weight;
+ blkio_update_group_weight(blkg, weight);
+ break;
+ case BLKIO_POLICY_THROTL:
+ switch(pn->fileid) {
+ case BLKIO_THROTL_read_bps_device:
+ case BLKIO_THROTL_write_bps_device:
+ bps = pn->val.bps ? pn->val.bps : (-1);
+ blkio_update_group_bps(blkg, bps, pn->fileid);
+ break;
+ case BLKIO_THROTL_read_iops_device:
+ case BLKIO_THROTL_write_iops_device:
+ iops = pn->val.iops ? pn->val.iops : (-1);
+ blkio_update_group_iops(blkg, iops, pn->fileid);
+ break;
+ }
+ break;
+ default:
+ BUG();
+ }
+}
+
+/*
+ * A policy node rule has been updated. Propogate this update to all the
+ * block groups which might be affected by this update.
+ */
+static void blkio_update_policy_node_blkg(struct blkio_cgroup *blkcg,
+ struct blkio_policy_node *pn)
+{
+ struct blkio_group *blkg;
+ struct hlist_node *n;
+
+ spin_lock(&blkio_list_lock);
+ spin_lock_irq(&blkcg->lock);
+
+ hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) {
+ if (pn->dev != blkg->dev || pn->plid != blkg->plid)
+ continue;
+ blkio_update_blkg_policy(blkcg, blkg, pn);
+ }
+
+ spin_unlock_irq(&blkcg->lock);
+ spin_unlock(&blkio_list_lock);
+}
-static int blkiocg_weight_device_write(struct cgroup *cgrp, struct cftype *cft,
- const char *buffer)
+static int blkiocg_file_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;
+ enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private);
+ int fileid = BLKIOFILE_ATTR(cft->private);
buf = kstrdup(buffer, GFP_KERNEL);
if (!buf)
@@ -751,7 +941,7 @@ static int blkiocg_weight_device_write(struct cgroup *cgrp, struct cftype *cft,
goto free_buf;
}
- ret = blkio_policy_parse_and_set(buf, newpn);
+ ret = blkio_policy_parse_and_set(buf, newpn, plid, fileid);
if (ret)
goto free_newpn;
@@ -759,9 +949,9 @@ static int blkiocg_weight_device_write(struct cgroup *cgrp, struct cftype *cft,
spin_lock_irq(&blkcg->lock);
- pn = blkio_policy_search_node(blkcg, newpn->dev);
+ pn = blkio_policy_search_node(blkcg, newpn->dev, plid, fileid);
if (!pn) {
- if (newpn->weight != 0) {
+ if (!blkio_delete_rule_command(newpn)) {
blkio_policy_insert_node(blkcg, newpn);
keep_newpn = 1;
}
@@ -769,33 +959,17 @@ static int blkiocg_weight_device_write(struct cgroup *cgrp, struct cftype *cft,
goto update_io_group;
}
- if (newpn->weight == 0) {
- /* weight == 0 means deleteing a specific weight */
+ if (blkio_delete_rule_command(newpn)) {
blkio_policy_delete_node(pn);
spin_unlock_irq(&blkcg->lock);
goto update_io_group;
}
spin_unlock_irq(&blkcg->lock);
- pn->weight = newpn->weight;
+ blkio_update_policy_rule(pn, newpn);
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);
+ blkio_update_policy_node_blkg(blkcg, newpn);
free_newpn:
if (!keep_newpn)
@@ -805,23 +979,256 @@ free_buf:
return ret;
}
-static int blkiocg_weight_device_read(struct cgroup *cgrp, struct cftype *cft,
- struct seq_file *m)
+static void
+blkio_print_policy_node(struct seq_file *m, struct blkio_policy_node *pn)
{
- struct blkio_cgroup *blkcg;
- struct blkio_policy_node *pn;
+ switch(pn->plid) {
+ case BLKIO_POLICY_PROP:
+ if (pn->fileid == BLKIO_PROP_weight_device)
+ seq_printf(m, "%u:%u\t%u\n", MAJOR(pn->dev),
+ MINOR(pn->dev), pn->val.weight);
+ break;
+ case BLKIO_POLICY_THROTL:
+ switch(pn->fileid) {
+ case BLKIO_THROTL_read_bps_device:
+ case BLKIO_THROTL_write_bps_device:
+ seq_printf(m, "%u:%u\t%llu\n", MAJOR(pn->dev),
+ MINOR(pn->dev), pn->val.bps);
+ break;
+ case BLKIO_THROTL_read_iops_device:
+ case BLKIO_THROTL_write_iops_device:
+ seq_printf(m, "%u:%u\t%u\n", MAJOR(pn->dev),
+ MINOR(pn->dev), pn->val.iops);
+ break;
+ }
+ break;
+ default:
+ BUG();
+ }
+}
- seq_printf(m, "dev\tweight\n");
+/* cgroup files which read their data from policy nodes end up here */
+static void blkio_read_policy_node_files(struct cftype *cft,
+ struct blkio_cgroup *blkcg, struct seq_file *m)
+{
+ struct blkio_policy_node *pn;
- blkcg = cgroup_to_blkio_cgroup(cgrp);
if (!list_empty(&blkcg->policy_list)) {
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);
+ if (!pn_matches_cftype(cft, pn))
+ continue;
+ blkio_print_policy_node(m, pn);
}
spin_unlock_irq(&blkcg->lock);
}
+}
+
+static int blkiocg_file_read(struct cgroup *cgrp, struct cftype *cft,
+ struct seq_file *m)
+{
+ struct blkio_cgroup *blkcg;
+ enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private);
+ int name = BLKIOFILE_ATTR(cft->private);
+
+ blkcg = cgroup_to_blkio_cgroup(cgrp);
+
+ switch(plid) {
+ case BLKIO_POLICY_PROP:
+ switch(name) {
+ case BLKIO_PROP_weight_device:
+ blkio_read_policy_node_files(cft, blkcg, m);
+ return 0;
+ default:
+ BUG();
+ }
+ break;
+ case BLKIO_POLICY_THROTL:
+ switch(name){
+ case BLKIO_THROTL_read_bps_device:
+ case BLKIO_THROTL_write_bps_device:
+ case BLKIO_THROTL_read_iops_device:
+ case BLKIO_THROTL_write_iops_device:
+ blkio_read_policy_node_files(cft, blkcg, m);
+ return 0;
+ default:
+ BUG();
+ }
+ break;
+ default:
+ BUG();
+ }
+
+ return 0;
+}
+
+static int blkio_read_blkg_stats(struct blkio_cgroup *blkcg,
+ struct cftype *cft, struct cgroup_map_cb *cb, enum stat_type type,
+ bool show_total)
+{
+ struct blkio_group *blkg;
+ struct hlist_node *n;
+ uint64_t cgroup_total = 0;
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(blkg, n, &blkcg->blkg_list, blkcg_node) {
+ if (blkg->dev) {
+ if (!cftype_blkg_same_policy(cft, blkg))
+ continue;
+ 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();
+ return 0;
+}
+
+/* All map kind of cgroup file get serviced by this function */
+static int blkiocg_file_read_map(struct cgroup *cgrp, struct cftype *cft,
+ struct cgroup_map_cb *cb)
+{
+ struct blkio_cgroup *blkcg;
+ enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private);
+ int name = BLKIOFILE_ATTR(cft->private);
+
+ blkcg = cgroup_to_blkio_cgroup(cgrp);
+
+ switch(plid) {
+ case BLKIO_POLICY_PROP:
+ switch(name) {
+ case BLKIO_PROP_time:
+ return blkio_read_blkg_stats(blkcg, cft, cb,
+ BLKIO_STAT_TIME, 0);
+ case BLKIO_PROP_sectors:
+ return blkio_read_blkg_stats(blkcg, cft, cb,
+ BLKIO_STAT_SECTORS, 0);
+ case BLKIO_PROP_io_service_bytes:
+ return blkio_read_blkg_stats(blkcg, cft, cb,
+ BLKIO_STAT_SERVICE_BYTES, 1);
+ case BLKIO_PROP_io_serviced:
+ return blkio_read_blkg_stats(blkcg, cft, cb,
+ BLKIO_STAT_SERVICED, 1);
+ case BLKIO_PROP_io_service_time:
+ return blkio_read_blkg_stats(blkcg, cft, cb,
+ BLKIO_STAT_SERVICE_TIME, 1);
+ case BLKIO_PROP_io_wait_time:
+ return blkio_read_blkg_stats(blkcg, cft, cb,
+ BLKIO_STAT_WAIT_TIME, 1);
+ case BLKIO_PROP_io_merged:
+ return blkio_read_blkg_stats(blkcg, cft, cb,
+ BLKIO_STAT_MERGED, 1);
+ case BLKIO_PROP_io_queued:
+ return blkio_read_blkg_stats(blkcg, cft, cb,
+ BLKIO_STAT_QUEUED, 1);
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+ case BLKIO_PROP_dequeue:
+ return blkio_read_blkg_stats(blkcg, cft, cb,
+ BLKIO_STAT_DEQUEUE, 0);
+ case BLKIO_PROP_avg_queue_size:
+ return blkio_read_blkg_stats(blkcg, cft, cb,
+ BLKIO_STAT_AVG_QUEUE_SIZE, 0);
+ case BLKIO_PROP_group_wait_time:
+ return blkio_read_blkg_stats(blkcg, cft, cb,
+ BLKIO_STAT_GROUP_WAIT_TIME, 0);
+ case BLKIO_PROP_idle_time:
+ return blkio_read_blkg_stats(blkcg, cft, cb,
+ BLKIO_STAT_IDLE_TIME, 0);
+ case BLKIO_PROP_empty_time:
+ return blkio_read_blkg_stats(blkcg, cft, cb,
+ BLKIO_STAT_EMPTY_TIME, 0);
+#endif
+ default:
+ BUG();
+ }
+ break;
+ case BLKIO_POLICY_THROTL:
+ switch(name){
+ case BLKIO_THROTL_io_service_bytes:
+ return blkio_read_blkg_stats(blkcg, cft, cb,
+ BLKIO_STAT_SERVICE_BYTES, 1);
+ case BLKIO_THROTL_io_serviced:
+ return blkio_read_blkg_stats(blkcg, cft, cb,
+ BLKIO_STAT_SERVICED, 1);
+ default:
+ BUG();
+ }
+ break;
+ default:
+ BUG();
+ }
+
+ return 0;
+}
+
+static int blkio_weight_write(struct blkio_cgroup *blkcg, u64 val)
+{
+ struct blkio_group *blkg;
+ struct hlist_node *n;
+ struct blkio_policy_node *pn;
+
+ if (val < BLKIO_WEIGHT_MIN || val > BLKIO_WEIGHT_MAX)
+ return -EINVAL;
+
+ 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,
+ BLKIO_POLICY_PROP, BLKIO_PROP_weight_device);
+ if (pn)
+ continue;
+
+ blkio_update_group_weight(blkg, blkcg->weight);
+ }
+ spin_unlock_irq(&blkcg->lock);
+ spin_unlock(&blkio_list_lock);
+ return 0;
+}
+
+static u64 blkiocg_file_read_u64 (struct cgroup *cgrp, struct cftype *cft) {
+ struct blkio_cgroup *blkcg;
+ enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private);
+ int name = BLKIOFILE_ATTR(cft->private);
+
+ blkcg = cgroup_to_blkio_cgroup(cgrp);
+
+ switch(plid) {
+ case BLKIO_POLICY_PROP:
+ switch(name) {
+ case BLKIO_PROP_weight:
+ return (u64)blkcg->weight;
+ }
+ break;
+ default:
+ BUG();
+ }
+ return 0;
+}
+
+static int
+blkiocg_file_write_u64(struct cgroup *cgrp, struct cftype *cft, u64 val)
+{
+ struct blkio_cgroup *blkcg;
+ enum blkio_policy_id plid = BLKIOFILE_POLICY(cft->private);
+ int name = BLKIOFILE_ATTR(cft->private);
+
+ blkcg = cgroup_to_blkio_cgroup(cgrp);
+
+ switch(plid) {
+ case BLKIO_POLICY_PROP:
+ switch(name) {
+ case BLKIO_PROP_weight:
+ return blkio_weight_write(blkcg, val);
+ }
+ break;
+ default:
+ BUG();
+ }
return 0;
}
@@ -829,71 +1236,151 @@ static int blkiocg_weight_device_read(struct cgroup *cgrp, struct cftype *cft,
struct cftype blkio_files[] = {
{
.name = "weight_device",
- .read_seq_string = blkiocg_weight_device_read,
- .write_string = blkiocg_weight_device_write,
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP,
+ BLKIO_PROP_weight_device),
+ .read_seq_string = blkiocg_file_read,
+ .write_string = blkiocg_file_write,
.max_write_len = 256,
},
{
.name = "weight",
- .read_u64 = blkiocg_weight_read,
- .write_u64 = blkiocg_weight_write,
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP,
+ BLKIO_PROP_weight),
+ .read_u64 = blkiocg_file_read_u64,
+ .write_u64 = blkiocg_file_write_u64,
},
{
.name = "time",
- .read_map = blkiocg_time_read,
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP,
+ BLKIO_PROP_time),
+ .read_map = blkiocg_file_read_map,
},
{
.name = "sectors",
- .read_map = blkiocg_sectors_read,
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP,
+ BLKIO_PROP_sectors),
+ .read_map = blkiocg_file_read_map,
},
{
.name = "io_service_bytes",
- .read_map = blkiocg_io_service_bytes_read,
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP,
+ BLKIO_PROP_io_service_bytes),
+ .read_map = blkiocg_file_read_map,
},
{
.name = "io_serviced",
- .read_map = blkiocg_io_serviced_read,
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP,
+ BLKIO_PROP_io_serviced),
+ .read_map = blkiocg_file_read_map,
},
{
.name = "io_service_time",
- .read_map = blkiocg_io_service_time_read,
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP,
+ BLKIO_PROP_io_service_time),
+ .read_map = blkiocg_file_read_map,
},
{
.name = "io_wait_time",
- .read_map = blkiocg_io_wait_time_read,
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP,
+ BLKIO_PROP_io_wait_time),
+ .read_map = blkiocg_file_read_map,
},
{
.name = "io_merged",
- .read_map = blkiocg_io_merged_read,
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP,
+ BLKIO_PROP_io_merged),
+ .read_map = blkiocg_file_read_map,
},
{
.name = "io_queued",
- .read_map = blkiocg_io_queued_read,
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP,
+ BLKIO_PROP_io_queued),
+ .read_map = blkiocg_file_read_map,
},
{
.name = "reset_stats",
.write_u64 = blkiocg_reset_stats,
},
+#ifdef CONFIG_BLK_DEV_THROTTLING
+ {
+ .name = "throttle.read_bps_device",
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL,
+ BLKIO_THROTL_read_bps_device),
+ .read_seq_string = blkiocg_file_read,
+ .write_string = blkiocg_file_write,
+ .max_write_len = 256,
+ },
+
+ {
+ .name = "throttle.write_bps_device",
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL,
+ BLKIO_THROTL_write_bps_device),
+ .read_seq_string = blkiocg_file_read,
+ .write_string = blkiocg_file_write,
+ .max_write_len = 256,
+ },
+
+ {
+ .name = "throttle.read_iops_device",
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL,
+ BLKIO_THROTL_read_iops_device),
+ .read_seq_string = blkiocg_file_read,
+ .write_string = blkiocg_file_write,
+ .max_write_len = 256,
+ },
+
+ {
+ .name = "throttle.write_iops_device",
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL,
+ BLKIO_THROTL_write_iops_device),
+ .read_seq_string = blkiocg_file_read,
+ .write_string = blkiocg_file_write,
+ .max_write_len = 256,
+ },
+ {
+ .name = "throttle.io_service_bytes",
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL,
+ BLKIO_THROTL_io_service_bytes),
+ .read_map = blkiocg_file_read_map,
+ },
+ {
+ .name = "throttle.io_serviced",
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_THROTL,
+ BLKIO_THROTL_io_serviced),
+ .read_map = blkiocg_file_read_map,
+ },
+#endif /* CONFIG_BLK_DEV_THROTTLING */
+
#ifdef CONFIG_DEBUG_BLK_CGROUP
{
.name = "avg_queue_size",
- .read_map = blkiocg_avg_queue_size_read,
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP,
+ BLKIO_PROP_avg_queue_size),
+ .read_map = blkiocg_file_read_map,
},
{
.name = "group_wait_time",
- .read_map = blkiocg_group_wait_time_read,
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP,
+ BLKIO_PROP_group_wait_time),
+ .read_map = blkiocg_file_read_map,
},
{
.name = "idle_time",
- .read_map = blkiocg_idle_time_read,
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP,
+ BLKIO_PROP_idle_time),
+ .read_map = blkiocg_file_read_map,
},
{
.name = "empty_time",
- .read_map = blkiocg_empty_time_read,
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP,
+ BLKIO_PROP_empty_time),
+ .read_map = blkiocg_file_read_map,
},
{
.name = "dequeue",
- .read_map = blkiocg_dequeue_read,
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP,
+ BLKIO_PROP_dequeue),
+ .read_map = blkiocg_file_read_map,
},
#endif
};
@@ -932,13 +1419,14 @@ static void blkiocg_destroy(struct cgroup_subsys *subsys, struct cgroup *cgroup)
/*
* This blkio_group is being unlinked as associated cgroup is
* going away. Let all the IO controlling policies know about
- * this event. Currently this is static call to one io
- * controlling policy. Once we have more policies in place, we
- * need some dynamic registration of callback function.
+ * this event.
*/
spin_lock(&blkio_list_lock);
- list_for_each_entry(blkiop, &blkio_list, list)
+ list_for_each_entry(blkiop, &blkio_list, list) {
+ if (blkiop->plid != blkg->plid)
+ continue;
blkiop->ops.blkio_unlink_group_fn(key, blkg);
+ }
spin_unlock(&blkio_list_lock);
} while (1);
diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
index 2b866ec1dce..ea4861bdd54 100644
--- a/block/blk-cgroup.h
+++ b/block/blk-cgroup.h
@@ -15,6 +15,14 @@
#include <linux/cgroup.h>
+enum blkio_policy_id {
+ BLKIO_POLICY_PROP = 0, /* Proportional Bandwidth division */
+ BLKIO_POLICY_THROTL, /* Throttling */
+};
+
+/* Max limits for throttle policy */
+#define THROTL_IOPS_MAX UINT_MAX
+
#if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE)
#ifndef CONFIG_BLK_CGROUP
@@ -65,6 +73,35 @@ enum blkg_state_flags {
BLKG_empty,
};
+/* cgroup files owned by proportional weight policy */
+enum blkcg_file_name_prop {
+ BLKIO_PROP_weight = 1,
+ BLKIO_PROP_weight_device,
+ BLKIO_PROP_io_service_bytes,
+ BLKIO_PROP_io_serviced,
+ BLKIO_PROP_time,
+ BLKIO_PROP_sectors,
+ BLKIO_PROP_io_service_time,
+ BLKIO_PROP_io_wait_time,
+ BLKIO_PROP_io_merged,
+ BLKIO_PROP_io_queued,
+ BLKIO_PROP_avg_queue_size,
+ BLKIO_PROP_group_wait_time,
+ BLKIO_PROP_idle_time,
+ BLKIO_PROP_empty_time,
+ BLKIO_PROP_dequeue,
+};
+
+/* cgroup files owned by throttle policy */
+enum blkcg_file_name_throtl {
+ BLKIO_THROTL_read_bps_device,
+ BLKIO_THROTL_write_bps_device,
+ BLKIO_THROTL_read_iops_device,
+ BLKIO_THROTL_write_iops_device,
+ BLKIO_THROTL_io_service_bytes,
+ BLKIO_THROTL_io_serviced,
+};
+
struct blkio_cgroup {
struct cgroup_subsys_state css;
unsigned int weight;
@@ -112,6 +149,8 @@ struct blkio_group {
char path[128];
/* The device MKDEV(major, minor), this group has been created for */
dev_t dev;
+ /* policy which owns this blk group */
+ enum blkio_policy_id plid;
/* Need to serialize the stats in the case of reset/update */
spinlock_t stats_lock;
@@ -121,24 +160,60 @@ struct blkio_group {
struct blkio_policy_node {
struct list_head node;
dev_t dev;
- unsigned int weight;
+ /* This node belongs to max bw policy or porportional weight policy */
+ enum blkio_policy_id plid;
+ /* cgroup file to which this rule belongs to */
+ int fileid;
+
+ union {
+ unsigned int weight;
+ /*
+ * Rate read/write in terms of byptes per second
+ * Whether this rate represents read or write is determined
+ * by file type "fileid".
+ */
+ u64 bps;
+ unsigned int iops;
+ } val;
};
extern unsigned int blkcg_get_weight(struct blkio_cgroup *blkcg,
dev_t dev);
+extern uint64_t blkcg_get_read_bps(struct blkio_cgroup *blkcg,
+ dev_t dev);
+extern uint64_t blkcg_get_write_bps(struct blkio_cgroup *blkcg,
+ dev_t dev);
+extern unsigned int blkcg_get_read_iops(struct blkio_cgroup *blkcg,
+ dev_t dev);
+extern unsigned int blkcg_get_write_iops(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);
+
+typedef void (blkio_update_group_weight_fn) (void *key,
+ struct blkio_group *blkg, unsigned int weight);
+typedef void (blkio_update_group_read_bps_fn) (void * key,
+ struct blkio_group *blkg, u64 read_bps);
+typedef void (blkio_update_group_write_bps_fn) (void *key,
+ struct blkio_group *blkg, u64 write_bps);
+typedef void (blkio_update_group_read_iops_fn) (void *key,
+ struct blkio_group *blkg, unsigned int read_iops);
+typedef void (blkio_update_group_write_iops_fn) (void *key,
+ struct blkio_group *blkg, unsigned int write_iops);
struct blkio_policy_ops {
blkio_unlink_group_fn *blkio_unlink_group_fn;
blkio_update_group_weight_fn *blkio_update_group_weight_fn;
+ blkio_update_group_read_bps_fn *blkio_update_group_read_bps_fn;
+ blkio_update_group_write_bps_fn *blkio_update_group_write_bps_fn;
+ blkio_update_group_read_iops_fn *blkio_update_group_read_iops_fn;
+ blkio_update_group_write_iops_fn *blkio_update_group_write_iops_fn;
};
struct blkio_policy_type {
struct list_head list;
struct blkio_policy_ops ops;
+ enum blkio_policy_id plid;
};
/* Blkio controller policy registration */
@@ -212,7 +287,8 @@ static inline void blkiocg_set_start_empty_time(struct blkio_group *blkg) {}
extern struct blkio_cgroup blkio_root_cgroup;
extern struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup);
extern 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,
+ enum blkio_policy_id plid);
extern int blkiocg_del_blkio_group(struct blkio_group *blkg);
extern struct blkio_group *blkiocg_lookup_group(struct blkio_cgroup *blkcg,
void *key);
@@ -234,7 +310,8 @@ 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,
+ enum blkio_policy_id plid) {}
static inline int
blkiocg_del_blkio_group(struct blkio_group *blkg) { return 0; }
diff --git a/block/blk-core.c b/block/blk-core.c
index 32a1c123dfb..500eb859886 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -64,13 +64,15 @@ static void drive_stat_acct(struct request *rq, int new_io)
return;
cpu = part_stat_lock();
- part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq));
- if (!new_io)
+ if (!new_io) {
+ part = rq->part;
part_stat_inc(cpu, part, merges[rw]);
- else {
+ } else {
+ part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq));
part_round_stats(cpu, part);
part_inc_in_flight(part, rw);
+ rq->part = part;
}
part_stat_unlock();
@@ -128,6 +130,7 @@ void blk_rq_init(struct request_queue *q, struct request *rq)
rq->ref_count = 1;
rq->start_time = jiffies;
set_start_time_ns(rq);
+ rq->part = NULL;
}
EXPORT_SYMBOL(blk_rq_init);
@@ -382,6 +385,7 @@ void blk_sync_queue(struct request_queue *q)
del_timer_sync(&q->unplug_timer);
del_timer_sync(&q->timeout);
cancel_work_sync(&q->unplug_work);
+ throtl_shutdown_timer_wq(q);
}
EXPORT_SYMBOL(blk_sync_queue);
@@ -459,6 +463,8 @@ void blk_cleanup_queue(struct request_queue *q)
if (q->elevator)
elevator_exit(q->elevator);
+ blk_throtl_exit(q);
+
blk_put_queue(q);
}
EXPORT_SYMBOL(blk_cleanup_queue);
@@ -515,6 +521,11 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
return NULL;
}
+ if (blk_throtl_init(q)) {
+ kmem_cache_free(blk_requestq_cachep, q);
+ return NULL;
+ }
+
setup_timer(&q->backing_dev_info.laptop_mode_wb_timer,
laptop_mode_timer_fn, (unsigned long) q);
init_timer(&q->unplug_timer);
@@ -796,11 +807,16 @@ static struct request *get_request(struct request_queue *q, int rw_flags,
rl->starved[is_sync] = 0;
priv = !test_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
- if (priv)
+ if (priv) {
rl->elvpriv++;
- if (blk_queue_io_stat(q))
- rw_flags |= REQ_IO_STAT;
+ /*
+ * Don't do stats for non-priv requests
+ */
+ if (blk_queue_io_stat(q))
+ rw_flags |= REQ_IO_STAT;
+ }
+
spin_unlock_irq(q->queue_lock);
rq = blk_alloc_request(q, rw_flags, priv, gfp_mask);
@@ -1522,6 +1538,15 @@ static inline void __generic_make_request(struct bio *bio)
goto end_io;
}
+ blk_throtl_bio(q, &bio);
+
+ /*
+ * If bio = NULL, bio has been throttled and will be submitted
+ * later.
+ */
+ if (!bio)
+ break;
+
trace_block_bio_queue(q, bio);
ret = q->make_request_fn(q, bio);
@@ -1612,11 +1637,12 @@ void submit_bio(int rw, struct bio *bio)
if (unlikely(block_dump)) {
char b[BDEVNAME_SIZE];
- printk(KERN_DEBUG "%s(%d): %s block %Lu on %s\n",
+ printk(KERN_DEBUG "%s(%d): %s block %Lu on %s (%u sectors)\n",
current->comm, task_pid_nr(current),
(rw & WRITE) ? "WRITE" : "READ",
(unsigned long long)bio->bi_sector,
- bdevname(bio->bi_bdev, b));
+ bdevname(bio->bi_bdev, b),
+ count);
}
}
@@ -1759,7 +1785,7 @@ static void blk_account_io_completion(struct request *req, unsigned int bytes)
int cpu;
cpu = part_stat_lock();
- part = disk_map_sector_rcu(req->rq_disk, blk_rq_pos(req));
+ part = req->part;
part_stat_add(cpu, part, sectors[rw], bytes >> 9);
part_stat_unlock();
}
@@ -1779,7 +1805,7 @@ static void blk_account_io_done(struct request *req)
int cpu;
cpu = part_stat_lock();
- part = disk_map_sector_rcu(req->rq_disk, blk_rq_pos(req));
+ part = req->part;
part_stat_inc(cpu, part, ios[rw]);
part_stat_add(cpu, part, ticks[rw], duration);
@@ -2579,6 +2605,13 @@ int kblockd_schedule_work(struct request_queue *q, struct work_struct *work)
}
EXPORT_SYMBOL(kblockd_schedule_work);
+int kblockd_schedule_delayed_work(struct request_queue *q,
+ struct delayed_work *dwork, unsigned long delay)
+{
+ return queue_delayed_work(kblockd_workqueue, dwork, delay);
+}
+EXPORT_SYMBOL(kblockd_schedule_delayed_work);
+
int __init blk_dev_init(void)
{
BUILD_BUG_ON(__REQ_NR_BITS > 8 *
diff --git a/block/blk-exec.c b/block/blk-exec.c
index e1672f14840..cf1456a02ac 100644
--- a/block/blk-exec.c
+++ b/block/blk-exec.c
@@ -80,6 +80,7 @@ int blk_execute_rq(struct request_queue *q, struct gendisk *bd_disk,
DECLARE_COMPLETION_ONSTACK(wait);
char sense[SCSI_SENSE_BUFFERSIZE];
int err = 0;
+ unsigned long hang_check;
/*
* we need an extra reference to the request, so we can look at
@@ -95,7 +96,13 @@ int blk_execute_rq(struct request_queue *q, struct gendisk *bd_disk,
rq->end_io_data = &wait;
blk_execute_rq_nowait(q, bd_disk, rq, at_head, blk_end_sync_rq);
- wait_for_completion(&wait);
+
+ /* Prevent hang_check timer from firing at us during very long I/O */
+ hang_check = sysctl_hung_task_timeout_secs;
+ if (hang_check)
+ while (!wait_for_completion_timeout(&wait, hang_check * (HZ/2)));
+ else
+ wait_for_completion(&wait);
if (rq->errors)
err = -EIO;
diff --git a/block/blk-integrity.c b/block/blk-integrity.c
index edce1ef7933..54bcba6c02a 100644
--- a/block/blk-integrity.c
+++ b/block/blk-integrity.c
@@ -32,24 +32,37 @@ static struct kmem_cache *integrity_cachep;
/**
* blk_rq_count_integrity_sg - Count number of integrity scatterlist elements
- * @rq: request with integrity metadata attached
+ * @q: request queue
+ * @bio: bio with integrity metadata attached
*
* Description: Returns the number of elements required in a
- * scatterlist corresponding to the integrity metadata in a request.
+ * scatterlist corresponding to the integrity metadata in a bio.
*/
-int blk_rq_count_integrity_sg(struct request *rq)
+int blk_rq_count_integrity_sg(struct request_queue *q, struct bio *bio)
{
- struct bio_vec *iv, *ivprv;
- struct req_iterator iter;
- unsigned int segments;
+ struct bio_vec *iv, *ivprv = NULL;
+ unsigned int segments = 0;
+ unsigned int seg_size = 0;
+ unsigned int i = 0;
- ivprv = NULL;
- segments = 0;
+ bio_for_each_integrity_vec(iv, bio, i) {
- rq_for_each_integrity_segment(iv, rq, iter) {
+ if (ivprv) {
+ if (!BIOVEC_PHYS_MERGEABLE(ivprv, iv))
+ goto new_segment;
+
+ if (!BIOVEC_SEG_BOUNDARY(q, ivprv, iv))
+ goto new_segment;
- if (!ivprv || !BIOVEC_PHYS_MERGEABLE(ivprv, iv))
+ if (seg_size + iv->bv_len > queue_max_segment_size(q))
+ goto new_segment;
+
+ seg_size += iv->bv_len;
+ } else {
+new_segment:
segments++;
+ seg_size = iv->bv_len;
+ }
ivprv = iv;
}
@@ -60,30 +73,34 @@ EXPORT_SYMBOL(blk_rq_count_integrity_sg);
/**
* blk_rq_map_integrity_sg - Map integrity metadata into a scatterlist
- * @rq: request with integrity metadata attached
+ * @q: request queue
+ * @bio: bio with integrity metadata attached
* @sglist: target scatterlist
*
* Description: Map the integrity vectors in request into a
* scatterlist. The scatterlist must be big enough to hold all
* elements. I.e. sized using blk_rq_count_integrity_sg().
*/
-int blk_rq_map_integrity_sg(struct request *rq, struct scatterlist *sglist)
+int blk_rq_map_integrity_sg(struct request_queue *q, struct bio *bio,
+ struct scatterlist *sglist)
{
- struct bio_vec *iv, *ivprv;
- struct req_iterator iter;
- struct scatterlist *sg;
- unsigned int segments;
-
- ivprv = NULL;
- sg = NULL;
- segments = 0;
+ struct bio_vec *iv, *ivprv = NULL;
+ struct scatterlist *sg = NULL;
+ unsigned int segments = 0;
+ unsigned int i = 0;
- rq_for_each_integrity_segment(iv, rq, iter) {
+ bio_for_each_integrity_vec(iv, bio, i) {
if (ivprv) {
if (!BIOVEC_PHYS_MERGEABLE(ivprv, iv))
goto new_segment;
+ if (!BIOVEC_SEG_BOUNDARY(q, ivprv, iv))
+ goto new_segment;
+
+ if (sg->length + iv->bv_len > queue_max_segment_size(q))
+ goto new_segment;
+
sg->length += iv->bv_len;
} else {
new_segment:
@@ -162,6 +179,40 @@ int blk_integrity_compare(struct gendisk *gd1, struct gendisk *gd2)
}
EXPORT_SYMBOL(blk_integrity_compare);
+int blk_integrity_merge_rq(struct request_queue *q, struct request *req,
+ struct request *next)
+{
+ if (blk_integrity_rq(req) != blk_integrity_rq(next))
+ return -1;
+
+ if (req->nr_integrity_segments + next->nr_integrity_segments >
+ q->limits.max_integrity_segments)
+ return -1;
+
+ return 0;
+}
+EXPORT_SYMBOL(blk_integrity_merge_rq);
+
+int blk_integrity_merge_bio(struct request_queue *q, struct request *req,
+ struct bio *bio)
+{
+ int nr_integrity_segs;
+ struct bio *next = bio->bi_next;
+
+ bio->bi_next = NULL;
+ nr_integrity_segs = blk_rq_count_integrity_sg(q, bio);
+ bio->bi_next = next;
+
+ if (req->nr_integrity_segments + nr_integrity_segs >
+ q->limits.max_integrity_segments)
+ return -1;
+
+ req->nr_integrity_segments += nr_integrity_segs;
+
+ return 0;
+}
+EXPORT_SYMBOL(blk_integrity_merge_bio);
+
struct integrity_sysfs_entry {
struct attribute attr;
ssize_t (*show)(struct blk_integrity *, char *);
@@ -381,7 +432,6 @@ void blk_integrity_unregister(struct gendisk *disk)
kobject_uevent(&bi->kobj, KOBJ_REMOVE);
kobject_del(&bi->kobj);
kobject_put(&bi->kobj);
- kmem_cache_free(integrity_cachep, bi);
disk->integrity = NULL;
}
EXPORT_SYMBOL(blk_integrity_unregister);
diff --git a/block/blk-map.c b/block/blk-map.c
index ade0a08c909..d4a586d8691 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -54,7 +54,7 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
* direct dma. else, set up kernel bounce buffers
*/
uaddr = (unsigned long) ubuf;
- if (blk_rq_aligned(q, ubuf, len) && !map_data)
+ if (blk_rq_aligned(q, uaddr, len) && !map_data)
bio = bio_map_user(q, NULL, uaddr, len, reading, gfp_mask);
else
bio = bio_copy_user(q, map_data, uaddr, len, reading, gfp_mask);
@@ -288,6 +288,7 @@ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf,
unsigned int len, gfp_t gfp_mask)
{
int reading = rq_data_dir(rq) == READ;
+ unsigned long addr = (unsigned long) kbuf;
int do_copy = 0;
struct bio *bio;
int ret;
@@ -297,7 +298,7 @@ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf,
if (!len || !kbuf)
return -EINVAL;
- do_copy = !blk_rq_aligned(q, kbuf, len) || object_is_on_stack(kbuf);
+ do_copy = !blk_rq_aligned(q, addr, len) || object_is_on_stack(kbuf);
if (do_copy)
bio = bio_copy_kern(q, kbuf, len, gfp_mask, reading);
else
diff --git a/block/blk-merge.c b/block/blk-merge.c
index eafc94f68d7..0a2fd8a48a3 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -205,12 +205,11 @@ static inline int ll_new_hw_segment(struct request_queue *q,
{
int nr_phys_segs = bio_phys_segments(q, bio);
- if (req->nr_phys_segments + nr_phys_segs > queue_max_segments(q)) {
- req->cmd_flags |= REQ_NOMERGE;
- if (req == q->last_merge)
- q->last_merge = NULL;
- return 0;
- }
+ if (req->nr_phys_segments + nr_phys_segs > queue_max_segments(q))
+ goto no_merge;
+
+ if (bio_integrity(bio) && blk_integrity_merge_bio(q, req, bio))
+ goto no_merge;
/*
* This will form the start of a new hw segment. Bump both
@@ -218,6 +217,12 @@ static inline int ll_new_hw_segment(struct request_queue *q,
*/
req->nr_phys_segments += nr_phys_segs;
return 1;
+
+no_merge:
+ req->cmd_flags |= REQ_NOMERGE;
+ if (req == q->last_merge)
+ q->last_merge = NULL;
+ return 0;
}
int ll_back_merge_fn(struct request_queue *q, struct request *req,
@@ -301,6 +306,9 @@ static int ll_merge_requests_fn(struct request_queue *q, struct request *req,
if (total_phys_segments > queue_max_segments(q))
return 0;
+ if (blk_integrity_rq(req) && blk_integrity_merge_rq(q, req, next))
+ return 0;
+
/* Merge is OK... */
req->nr_phys_segments = total_phys_segments;
return 1;
@@ -343,7 +351,7 @@ static void blk_account_io_merge(struct request *req)
int cpu;
cpu = part_stat_lock();
- part = disk_map_sector_rcu(req->rq_disk, blk_rq_pos(req));
+ part = req->part;
part_round_stats(cpu, part);
part_dec_in_flight(part, rq_data_dir(req));
@@ -384,9 +392,6 @@ static int attempt_merge(struct request_queue *q, struct request *req,
|| next->special)
return 0;
- if (blk_integrity_rq(req) != blk_integrity_rq(next))
- return 0;
-
/*
* If we are allowed to merge, then append bio list
* from next to rq and release next. merge_requests_fn
diff --git a/block/blk-settings.c b/block/blk-settings.c
index a234f4bf1d6..315b88c8cbb 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -111,6 +111,7 @@ EXPORT_SYMBOL_GPL(blk_queue_lld_busy);
void blk_set_default_limits(struct queue_limits *lim)
{
lim->max_segments = BLK_MAX_SEGMENTS;
+ lim->max_integrity_segments = 0;
lim->seg_boundary_mask = BLK_SEG_BOUNDARY_MASK;
lim->max_segment_size = BLK_MAX_SEGMENT_SIZE;
lim->max_sectors = BLK_DEF_MAX_SECTORS;
@@ -213,7 +214,7 @@ void blk_queue_bounce_limit(struct request_queue *q, u64 dma_mask)
*/
if (b_pfn < (min_t(u64, 0xffffffffUL, BLK_BOUNCE_HIGH) >> PAGE_SHIFT))
dma = 1;
- q->limits.bounce_pfn = max_low_pfn;
+ q->limits.bounce_pfn = max(max_low_pfn, b_pfn);
#else
if (b_pfn < blk_max_low_pfn)
dma = 1;
@@ -343,7 +344,7 @@ EXPORT_SYMBOL(blk_queue_logical_block_size);
* hardware can operate on without reverting to read-modify-write
* operations.
*/
-void blk_queue_physical_block_size(struct request_queue *q, unsigned short size)
+void blk_queue_physical_block_size(struct request_queue *q, unsigned int size)
{
q->limits.physical_block_size = size;
@@ -455,11 +456,6 @@ void blk_queue_io_opt(struct request_queue *q, unsigned int opt)
}
EXPORT_SYMBOL(blk_queue_io_opt);
-/*
- * Returns the minimum that is _not_ zero, unless both are zero.
- */
-#define min_not_zero(l, r) (l == 0) ? r : ((r == 0) ? l : min(l, r))
-
/**
* blk_queue_stack_limits - inherit underlying queue limits for stacked drivers
* @t: the stacking driver (top)
@@ -514,6 +510,8 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
b->seg_boundary_mask);
t->max_segments = min_not_zero(t->max_segments, b->max_segments);
+ t->max_integrity_segments = min_not_zero(t->max_integrity_segments,
+ b->max_integrity_segments);
t->max_segment_size = min_not_zero(t->max_segment_size,
b->max_segment_size);
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 0749b89c688..da8a8a40cd4 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -112,6 +112,11 @@ static ssize_t queue_max_segments_show(struct request_queue *q, char *page)
return queue_var_show(queue_max_segments(q), (page));
}
+static ssize_t queue_max_integrity_segments_show(struct request_queue *q, char *page)
+{
+ return queue_var_show(q->limits.max_integrity_segments, (page));
+}
+
static ssize_t queue_max_segment_size_show(struct request_queue *q, char *page)
{
if (test_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags))
@@ -288,6 +293,11 @@ static struct queue_sysfs_entry queue_max_segments_entry = {
.show = queue_max_segments_show,
};
+static struct queue_sysfs_entry queue_max_integrity_segments_entry = {
+ .attr = {.name = "max_integrity_segments", .mode = S_IRUGO },
+ .show = queue_max_integrity_segments_show,
+};
+
static struct queue_sysfs_entry queue_max_segment_size_entry = {
.attr = {.name = "max_segment_size", .mode = S_IRUGO },
.show = queue_max_segment_size_show,
@@ -375,6 +385,7 @@ static struct attribute *default_attrs[] = {
&queue_max_hw_sectors_entry.attr,
&queue_max_sectors_entry.attr,
&queue_max_segments_entry.attr,
+ &queue_max_integrity_segments_entry.attr,
&queue_max_segment_size_entry.attr,
&queue_iosched_entry.attr,
&queue_hw_sector_size_entry.attr,
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
new file mode 100644
index 00000000000..56ad4531b41
--- /dev/null
+++ b/block/blk-throttle.c
@@ -0,0 +1,1123 @@
+/*
+ * Interface for controlling IO bandwidth on a request queue
+ *
+ * Copyright (C) 2010 Vivek Goyal <vgoyal@redhat.com>
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/blkdev.h>
+#include <linux/bio.h>
+#include <linux/blktrace_api.h>
+#include "blk-cgroup.h"
+
+/* Max dispatch from a group in 1 round */
+static int throtl_grp_quantum = 8;
+
+/* Total max dispatch from all groups in one round */
+static int throtl_quantum = 32;
+
+/* Throttling is performed over 100ms slice and after that slice is renewed */
+static unsigned long throtl_slice = HZ/10; /* 100 ms */
+
+struct throtl_rb_root {
+ struct rb_root rb;
+ struct rb_node *left;
+ unsigned int count;
+ unsigned long min_disptime;
+};
+
+#define THROTL_RB_ROOT (struct throtl_rb_root) { .rb = RB_ROOT, .left = NULL, \
+ .count = 0, .min_disptime = 0}
+
+#define rb_entry_tg(node) rb_entry((node), struct throtl_grp, rb_node)
+
+struct throtl_grp {
+ /* List of throtl groups on the request queue*/
+ struct hlist_node tg_node;
+
+ /* active throtl group service_tree member */
+ struct rb_node rb_node;
+
+ /*
+ * Dispatch time in jiffies. This is the estimated time when group
+ * will unthrottle and is ready to dispatch more bio. It is used as
+ * key to sort active groups in service tree.
+ */
+ unsigned long disptime;
+
+ struct blkio_group blkg;
+ atomic_t ref;
+ unsigned int flags;
+
+ /* Two lists for READ and WRITE */
+ struct bio_list bio_lists[2];
+
+ /* Number of queued bios on READ and WRITE lists */
+ unsigned int nr_queued[2];
+
+ /* bytes per second rate limits */
+ uint64_t bps[2];
+
+ /* IOPS limits */
+ unsigned int iops[2];
+
+ /* Number of bytes disptached in current slice */
+ uint64_t bytes_disp[2];
+ /* Number of bio's dispatched in current slice */
+ unsigned int io_disp[2];
+
+ /* When did we start a new slice */
+ unsigned long slice_start[2];
+ unsigned long slice_end[2];
+
+ /* Some throttle limits got updated for the group */
+ bool limits_changed;
+};
+
+struct throtl_data
+{
+ /* List of throtl groups */
+ struct hlist_head tg_list;
+
+ /* service tree for active throtl groups */
+ struct throtl_rb_root tg_service_tree;
+
+ struct throtl_grp root_tg;
+ struct request_queue *queue;
+
+ /* Total Number of queued bios on READ and WRITE lists */
+ unsigned int nr_queued[2];
+
+ /*
+ * number of total undestroyed groups
+ */
+ unsigned int nr_undestroyed_grps;
+
+ /* Work for dispatching throttled bios */
+ struct delayed_work throtl_work;
+
+ atomic_t limits_changed;
+};
+
+enum tg_state_flags {
+ THROTL_TG_FLAG_on_rr = 0, /* on round-robin busy list */
+};
+
+#define THROTL_TG_FNS(name) \
+static inline void throtl_mark_tg_##name(struct throtl_grp *tg) \
+{ \
+ (tg)->flags |= (1 << THROTL_TG_FLAG_##name); \
+} \
+static inline void throtl_clear_tg_##name(struct throtl_grp *tg) \
+{ \
+ (tg)->flags &= ~(1 << THROTL_TG_FLAG_##name); \
+} \
+static inline int throtl_tg_##name(const struct throtl_grp *tg) \
+{ \
+ return ((tg)->flags & (1 << THROTL_TG_FLAG_##name)) != 0; \
+}
+
+THROTL_TG_FNS(on_rr);
+
+#define throtl_log_tg(td, tg, fmt, args...) \
+ blk_add_trace_msg((td)->queue, "throtl %s " fmt, \
+ blkg_path(&(tg)->blkg), ##args); \
+
+#define throtl_log(td, fmt, args...) \
+ blk_add_trace_msg((td)->queue, "throtl " fmt, ##args)
+
+static inline struct throtl_grp *tg_of_blkg(struct blkio_group *blkg)
+{
+ if (blkg)
+ return container_of(blkg, struct throtl_grp, blkg);
+
+ return NULL;
+}
+
+static inline int total_nr_queued(struct throtl_data *td)
+{
+ return (td->nr_queued[0] + td->nr_queued[1]);
+}
+
+static inline struct throtl_grp *throtl_ref_get_tg(struct throtl_grp *tg)
+{
+ atomic_inc(&tg->ref);
+ return tg;
+}
+
+static void throtl_put_tg(struct throtl_grp *tg)
+{
+ BUG_ON(atomic_read(&tg->ref) <= 0);
+ if (!atomic_dec_and_test(&tg->ref))
+ return;
+ kfree(tg);
+}
+
+static struct throtl_grp * throtl_find_alloc_tg(struct throtl_data *td,
+ struct cgroup *cgroup)
+{
+ struct blkio_cgroup *blkcg = cgroup_to_blkio_cgroup(cgroup);
+ struct throtl_grp *tg = NULL;
+ void *key = td;
+ struct backing_dev_info *bdi = &td->queue->backing_dev_info;
+ unsigned int major, minor;
+
+ /*
+ * TODO: Speed up blkiocg_lookup_group() by maintaining a radix
+ * tree of blkg (instead of traversing through hash list all
+ * the time.
+ */
+ tg = tg_of_blkg(blkiocg_lookup_group(blkcg, key));
+
+ /* Fill in device details for root group */
+ if (tg && !tg->blkg.dev && bdi->dev && dev_name(bdi->dev)) {
+ sscanf(dev_name(bdi->dev), "%u:%u", &major, &minor);
+ tg->blkg.dev = MKDEV(major, minor);
+ goto done;
+ }
+
+ if (tg)
+ goto done;
+
+ tg = kzalloc_node(sizeof(*tg), GFP_ATOMIC, td->queue->node);
+ if (!tg)
+ goto done;
+
+ INIT_HLIST_NODE(&tg->tg_node);
+ RB_CLEAR_NODE(&tg->rb_node);
+ bio_list_init(&tg->bio_lists[0]);
+ bio_list_init(&tg->bio_lists[1]);
+
+ /*
+ * Take the initial reference that will be released on destroy
+ * This can be thought of a joint reference by cgroup and
+ * request queue which will be dropped by either request queue
+ * exit or cgroup deletion path depending on who is exiting first.
+ */
+ atomic_set(&tg->ref, 1);
+
+ /* Add group onto cgroup list */
+ sscanf(dev_name(bdi->dev), "%u:%u", &major, &minor);
+ blkiocg_add_blkio_group(blkcg, &tg->blkg, (void *)td,
+ MKDEV(major, minor), BLKIO_POLICY_THROTL);
+
+ tg->bps[READ] = blkcg_get_read_bps(blkcg, tg->blkg.dev);
+ tg->bps[WRITE] = blkcg_get_write_bps(blkcg, tg->blkg.dev);
+ tg->iops[READ] = blkcg_get_read_iops(blkcg, tg->blkg.dev);
+ tg->iops[WRITE] = blkcg_get_write_iops(blkcg, tg->blkg.dev);
+
+ hlist_add_head(&tg->tg_node, &td->tg_list);
+ td->nr_undestroyed_grps++;
+done:
+ return tg;
+}
+
+static struct throtl_grp * throtl_get_tg(struct throtl_data *td)
+{
+ struct cgroup *cgroup;
+ struct throtl_grp *tg = NULL;
+
+ rcu_read_lock();
+ cgroup = task_cgroup(current, blkio_subsys_id);
+ tg = throtl_find_alloc_tg(td, cgroup);
+ if (!tg)
+ tg = &td->root_tg;
+ rcu_read_unlock();
+ return tg;
+}
+
+static struct throtl_grp *throtl_rb_first(struct throtl_rb_root *root)
+{
+ /* Service tree is empty */
+ if (!root->count)
+ return NULL;
+
+ if (!root->left)
+ root->left = rb_first(&root->rb);
+
+ if (root->left)
+ return rb_entry_tg(root->left);
+
+ return NULL;
+}
+
+static void rb_erase_init(struct rb_node *n, struct rb_root *root)
+{
+ rb_erase(n, root);
+ RB_CLEAR_NODE(n);
+}
+
+static void throtl_rb_erase(struct rb_node *n, struct throtl_rb_root *root)
+{
+ if (root->left == n)
+ root->left = NULL;
+ rb_erase_init(n, &root->rb);
+ --root->count;
+}
+
+static void update_min_dispatch_time(struct throtl_rb_root *st)
+{
+ struct throtl_grp *tg;
+
+ tg = throtl_rb_first(st);
+ if (!tg)
+ return;
+
+ st->min_disptime = tg->disptime;
+}
+
+static void
+tg_service_tree_add(struct throtl_rb_root *st, struct throtl_grp *tg)
+{
+ struct rb_node **node = &st->rb.rb_node;
+ struct rb_node *parent = NULL;
+ struct throtl_grp *__tg;
+ unsigned long key = tg->disptime;
+ int left = 1;
+
+ while (*node != NULL) {
+ parent = *node;
+ __tg = rb_entry_tg(parent);
+
+ if (time_before(key, __tg->disptime))
+ node = &parent->rb_left;
+ else {
+ node = &parent->rb_right;
+ left = 0;
+ }
+ }
+
+ if (left)
+ st->left = &tg->rb_node;
+
+ rb_link_node(&tg->rb_node, parent, node);
+ rb_insert_color(&tg->rb_node, &st->rb);
+}
+
+static void __throtl_enqueue_tg(struct throtl_data *td, struct throtl_grp *tg)
+{
+ struct throtl_rb_root *st = &td->tg_service_tree;
+
+ tg_service_tree_add(st, tg);
+ throtl_mark_tg_on_rr(tg);
+ st->count++;
+}
+
+static void throtl_enqueue_tg(struct throtl_data *td, struct throtl_grp *tg)
+{
+ if (!throtl_tg_on_rr(tg))
+ __throtl_enqueue_tg(td, tg);
+}
+
+static void __throtl_dequeue_tg(struct throtl_data *td, struct throtl_grp *tg)
+{
+ throtl_rb_erase(&tg->rb_node, &td->tg_service_tree);
+ throtl_clear_tg_on_rr(tg);
+}
+
+static void throtl_dequeue_tg(struct throtl_data *td, struct throtl_grp *tg)
+{
+ if (throtl_tg_on_rr(tg))
+ __throtl_dequeue_tg(td, tg);
+}
+
+static void throtl_schedule_next_dispatch(struct throtl_data *td)
+{
+ struct throtl_rb_root *st = &td->tg_service_tree;
+
+ /*
+ * If there are more bios pending, schedule more work.
+ */
+ if (!total_nr_queued(td))
+ return;
+
+ BUG_ON(!st->count);
+
+ update_min_dispatch_time(st);
+
+ if (time_before_eq(st->min_disptime, jiffies))
+ throtl_schedule_delayed_work(td->queue, 0);
+ else
+ throtl_schedule_delayed_work(td->queue,
+ (st->min_disptime - jiffies));
+}
+
+static inline void
+throtl_start_new_slice(struct throtl_data *td, struct throtl_grp *tg, bool rw)
+{
+ tg->bytes_disp[rw] = 0;
+ tg->io_disp[rw] = 0;
+ tg->slice_start[rw] = jiffies;
+ tg->slice_end[rw] = jiffies + throtl_slice;
+ throtl_log_tg(td, tg, "[%c] new slice start=%lu end=%lu jiffies=%lu",
+ rw == READ ? 'R' : 'W', tg->slice_start[rw],
+ tg->slice_end[rw], jiffies);
+}
+
+static inline void throtl_extend_slice(struct throtl_data *td,
+ struct throtl_grp *tg, bool rw, unsigned long jiffy_end)
+{
+ tg->slice_end[rw] = roundup(jiffy_end, throtl_slice);
+ throtl_log_tg(td, tg, "[%c] extend slice start=%lu end=%lu jiffies=%lu",
+ rw == READ ? 'R' : 'W', tg->slice_start[rw],
+ tg->slice_end[rw], jiffies);
+}
+
+/* Determine if previously allocated or extended slice is complete or not */
+static bool
+throtl_slice_used(struct throtl_data *td, struct throtl_grp *tg, bool rw)
+{
+ if (time_in_range(jiffies, tg->slice_start[rw], tg->slice_end[rw]))
+ return 0;
+
+ return 1;
+}
+
+/* Trim the used slices and adjust slice start accordingly */
+static inline void
+throtl_trim_slice(struct throtl_data *td, struct throtl_grp *tg, bool rw)
+{
+ unsigned long nr_slices, time_elapsed, io_trim;
+ u64 bytes_trim, tmp;
+
+ BUG_ON(time_before(tg->slice_end[rw], tg->slice_start[rw]));
+
+ /*
+ * If bps are unlimited (-1), then time slice don't get
+ * renewed. Don't try to trim the slice if slice is used. A new
+ * slice will start when appropriate.
+ */
+ if (throtl_slice_used(td, tg, rw))
+ return;
+
+ time_elapsed = jiffies - tg->slice_start[rw];
+
+ nr_slices = time_elapsed / throtl_slice;
+
+ if (!nr_slices)
+ return;
+ tmp = tg->bps[rw] * throtl_slice * nr_slices;
+ do_div(tmp, HZ);
+ bytes_trim = tmp;
+
+ io_trim = (tg->iops[rw] * throtl_slice * nr_slices)/HZ;
+
+ if (!bytes_trim && !io_trim)
+ return;
+
+ if (tg->bytes_disp[rw] >= bytes_trim)
+ tg->bytes_disp[rw] -= bytes_trim;
+ else
+ tg->bytes_disp[rw] = 0;
+
+ if (tg->io_disp[rw] >= io_trim)
+ tg->io_disp[rw] -= io_trim;
+ else
+ tg->io_disp[rw] = 0;
+
+ tg->slice_start[rw] += nr_slices * throtl_slice;
+
+ throtl_log_tg(td, tg, "[%c] trim slice nr=%lu bytes=%llu io=%lu"
+ " start=%lu end=%lu jiffies=%lu",
+ rw == READ ? 'R' : 'W', nr_slices, bytes_trim, io_trim,
+ tg->slice_start[rw], tg->slice_end[rw], jiffies);
+}
+
+static bool tg_with_in_iops_limit(struct throtl_data *td, struct throtl_grp *tg,
+ struct bio *bio, unsigned long *wait)
+{
+ bool rw = bio_data_dir(bio);
+ unsigned int io_allowed;
+ unsigned long jiffy_elapsed, jiffy_wait, jiffy_elapsed_rnd;
+ u64 tmp;
+
+ jiffy_elapsed = jiffy_elapsed_rnd = jiffies - tg->slice_start[rw];
+
+ /* Slice has just started. Consider one slice interval */
+ if (!jiffy_elapsed)
+ jiffy_elapsed_rnd = throtl_slice;
+
+ jiffy_elapsed_rnd = roundup(jiffy_elapsed_rnd, throtl_slice);
+
+ /*
+ * jiffy_elapsed_rnd should not be a big value as minimum iops can be
+ * 1 then at max jiffy elapsed should be equivalent of 1 second as we
+ * will allow dispatch after 1 second and after that slice should
+ * have been trimmed.
+ */
+
+ tmp = (u64)tg->iops[rw] * jiffy_elapsed_rnd;
+ do_div(tmp, HZ);
+
+ if (tmp > UINT_MAX)
+ io_allowed = UINT_MAX;
+ else
+ io_allowed = tmp;
+
+ if (tg->io_disp[rw] + 1 <= io_allowed) {
+ if (wait)
+ *wait = 0;
+ return 1;
+ }
+
+ /* Calc approx time to dispatch */
+ jiffy_wait = ((tg->io_disp[rw] + 1) * HZ)/tg->iops[rw] + 1;
+
+ if (jiffy_wait > jiffy_elapsed)
+ jiffy_wait = jiffy_wait - jiffy_elapsed;
+ else
+ jiffy_wait = 1;
+
+ if (wait)
+ *wait = jiffy_wait;
+ return 0;
+}
+
+static bool tg_with_in_bps_limit(struct throtl_data *td, struct throtl_grp *tg,
+ struct bio *bio, unsigned long *wait)
+{
+ bool rw = bio_data_dir(bio);
+ u64 bytes_allowed, extra_bytes, tmp;
+ unsigned long jiffy_elapsed, jiffy_wait, jiffy_elapsed_rnd;
+
+ jiffy_elapsed = jiffy_elapsed_rnd = jiffies - tg->slice_start[rw];
+
+ /* Slice has just started. Consider one slice interval */
+ if (!jiffy_elapsed)
+ jiffy_elapsed_rnd = throtl_slice;
+
+ jiffy_elapsed_rnd = roundup(jiffy_elapsed_rnd, throtl_slice);
+
+ tmp = tg->bps[rw] * jiffy_elapsed_rnd;
+ do_div(tmp, HZ);
+ bytes_allowed = tmp;
+
+ if (tg->bytes_disp[rw] + bio->bi_size <= bytes_allowed) {
+ if (wait)
+ *wait = 0;
+ return 1;
+ }
+
+ /* Calc approx time to dispatch */
+ extra_bytes = tg->bytes_disp[rw] + bio->bi_size - bytes_allowed;
+ jiffy_wait = div64_u64(extra_bytes * HZ, tg->bps[rw]);
+
+ if (!jiffy_wait)
+ jiffy_wait = 1;
+
+ /*
+ * This wait time is without taking into consideration the rounding
+ * up we did. Add that time also.
+ */
+ jiffy_wait = jiffy_wait + (jiffy_elapsed_rnd - jiffy_elapsed);
+ if (wait)
+ *wait = jiffy_wait;
+ return 0;
+}
+
+/*
+ * Returns whether one can dispatch a bio or not. Also returns approx number
+ * of jiffies to wait before this bio is with-in IO rate and can be dispatched
+ */
+static bool tg_may_dispatch(struct throtl_data *td, struct throtl_grp *tg,
+ struct bio *bio, unsigned long *wait)
+{
+ bool rw = bio_data_dir(bio);
+ unsigned long bps_wait = 0, iops_wait = 0, max_wait = 0;
+
+ /*
+ * Currently whole state machine of group depends on first bio
+ * queued in the group bio list. So one should not be calling
+ * this function with a different bio if there are other bios
+ * queued.
+ */
+ BUG_ON(tg->nr_queued[rw] && bio != bio_list_peek(&tg->bio_lists[rw]));
+
+ /* If tg->bps = -1, then BW is unlimited */
+ if (tg->bps[rw] == -1 && tg->iops[rw] == -1) {
+ if (wait)
+ *wait = 0;
+ return 1;
+ }
+
+ /*
+ * If previous slice expired, start a new one otherwise renew/extend
+ * existing slice to make sure it is at least throtl_slice interval
+ * long since now.
+ */
+ if (throtl_slice_used(td, tg, rw))
+ throtl_start_new_slice(td, tg, rw);
+ else {
+ if (time_before(tg->slice_end[rw], jiffies + throtl_slice))
+ throtl_extend_slice(td, tg, rw, jiffies + throtl_slice);
+ }
+
+ if (tg_with_in_bps_limit(td, tg, bio, &bps_wait)
+ && tg_with_in_iops_limit(td, tg, bio, &iops_wait)) {
+ if (wait)
+ *wait = 0;
+ return 1;
+ }
+
+ max_wait = max(bps_wait, iops_wait);
+
+ if (wait)
+ *wait = max_wait;
+
+ if (time_before(tg->slice_end[rw], jiffies + max_wait))
+ throtl_extend_slice(td, tg, rw, jiffies + max_wait);
+
+ return 0;
+}
+
+static void throtl_charge_bio(struct throtl_grp *tg, struct bio *bio)
+{
+ bool rw = bio_data_dir(bio);
+ bool sync = bio->bi_rw & REQ_SYNC;
+
+ /* Charge the bio to the group */
+ tg->bytes_disp[rw] += bio->bi_size;
+ tg->io_disp[rw]++;
+
+ /*
+ * TODO: This will take blkg->stats_lock. Figure out a way
+ * to avoid this cost.
+ */
+ blkiocg_update_dispatch_stats(&tg->blkg, bio->bi_size, rw, sync);
+}
+
+static void throtl_add_bio_tg(struct throtl_data *td, struct throtl_grp *tg,
+ struct bio *bio)
+{
+ bool rw = bio_data_dir(bio);
+
+ bio_list_add(&tg->bio_lists[rw], bio);
+ /* Take a bio reference on tg */
+ throtl_ref_get_tg(tg);
+ tg->nr_queued[rw]++;
+ td->nr_queued[rw]++;
+ throtl_enqueue_tg(td, tg);
+}
+
+static void tg_update_disptime(struct throtl_data *td, struct throtl_grp *tg)
+{
+ unsigned long read_wait = -1, write_wait = -1, min_wait = -1, disptime;
+ struct bio *bio;
+
+ if ((bio = bio_list_peek(&tg->bio_lists[READ])))
+ tg_may_dispatch(td, tg, bio, &read_wait);
+
+ if ((bio = bio_list_peek(&tg->bio_lists[WRITE])))
+ tg_may_dispatch(td, tg, bio, &write_wait);
+
+ min_wait = min(read_wait, write_wait);
+ disptime = jiffies + min_wait;
+
+ /* Update dispatch time */
+ throtl_dequeue_tg(td, tg);
+ tg->disptime = disptime;
+ throtl_enqueue_tg(td, tg);
+}
+
+static void tg_dispatch_one_bio(struct throtl_data *td, struct throtl_grp *tg,
+ bool rw, struct bio_list *bl)
+{
+ struct bio *bio;
+
+ bio = bio_list_pop(&tg->bio_lists[rw]);
+ tg->nr_queued[rw]--;
+ /* Drop bio reference on tg */
+ throtl_put_tg(tg);
+
+ BUG_ON(td->nr_queued[rw] <= 0);
+ td->nr_queued[rw]--;
+
+ throtl_charge_bio(tg, bio);
+ bio_list_add(bl, bio);
+ bio->bi_rw |= REQ_THROTTLED;
+
+ throtl_trim_slice(td, tg, rw);
+}
+
+static int throtl_dispatch_tg(struct throtl_data *td, struct throtl_grp *tg,
+ struct bio_list *bl)
+{
+ unsigned int nr_reads = 0, nr_writes = 0;
+ unsigned int max_nr_reads = throtl_grp_quantum*3/4;
+ unsigned int max_nr_writes = throtl_grp_quantum - nr_reads;
+ struct bio *bio;
+
+ /* Try to dispatch 75% READS and 25% WRITES */
+
+ while ((bio = bio_list_peek(&tg->bio_lists[READ]))
+ && tg_may_dispatch(td, tg, bio, NULL)) {
+
+ tg_dispatch_one_bio(td, tg, bio_data_dir(bio), bl);
+ nr_reads++;
+
+ if (nr_reads >= max_nr_reads)
+ break;
+ }
+
+ while ((bio = bio_list_peek(&tg->bio_lists[WRITE]))
+ && tg_may_dispatch(td, tg, bio, NULL)) {
+
+ tg_dispatch_one_bio(td, tg, bio_data_dir(bio), bl);
+ nr_writes++;
+
+ if (nr_writes >= max_nr_writes)
+ break;
+ }
+
+ return nr_reads + nr_writes;
+}
+
+static int throtl_select_dispatch(struct throtl_data *td, struct bio_list *bl)
+{
+ unsigned int nr_disp = 0;
+ struct throtl_grp *tg;
+ struct throtl_rb_root *st = &td->tg_service_tree;
+
+ while (1) {
+ tg = throtl_rb_first(st);
+
+ if (!tg)
+ break;
+
+ if (time_before(jiffies, tg->disptime))
+ break;
+
+ throtl_dequeue_tg(td, tg);
+
+ nr_disp += throtl_dispatch_tg(td, tg, bl);
+
+ if (tg->nr_queued[0] || tg->nr_queued[1]) {
+ tg_update_disptime(td, tg);
+ throtl_enqueue_tg(td, tg);
+ }
+
+ if (nr_disp >= throtl_quantum)
+ break;
+ }
+
+ return nr_disp;
+}
+
+static void throtl_process_limit_change(struct throtl_data *td)
+{
+ struct throtl_grp *tg;
+ struct hlist_node *pos, *n;
+
+ /*
+ * Make sure atomic_inc() effects from
+ * throtl_update_blkio_group_read_bps(), group of functions are
+ * visible.
+ * Is this required or smp_mb__after_atomic_inc() was suffcient
+ * after the atomic_inc().
+ */
+ smp_rmb();
+ if (!atomic_read(&td->limits_changed))
+ return;
+
+ throtl_log(td, "limit changed =%d", atomic_read(&td->limits_changed));
+
+ hlist_for_each_entry_safe(tg, pos, n, &td->tg_list, tg_node) {
+ /*
+ * Do I need an smp_rmb() here to make sure tg->limits_changed
+ * update is visible. I am relying on smp_rmb() at the
+ * beginning of function and not putting a new one here.
+ */
+
+ if (throtl_tg_on_rr(tg) && tg->limits_changed) {
+ throtl_log_tg(td, tg, "limit change rbps=%llu wbps=%llu"
+ " riops=%u wiops=%u", tg->bps[READ],
+ tg->bps[WRITE], tg->iops[READ],
+ tg->iops[WRITE]);
+ tg_update_disptime(td, tg);
+ tg->limits_changed = false;
+ }
+ }
+
+ smp_mb__before_atomic_dec();
+ atomic_dec(&td->limits_changed);
+ smp_mb__after_atomic_dec();
+}
+
+/* Dispatch throttled bios. Should be called without queue lock held. */
+static int throtl_dispatch(struct request_queue *q)
+{
+ struct throtl_data *td = q->td;
+ unsigned int nr_disp = 0;
+ struct bio_list bio_list_on_stack;
+ struct bio *bio;
+
+ spin_lock_irq(q->queue_lock);
+
+ throtl_process_limit_change(td);
+
+ if (!total_nr_queued(td))
+ goto out;
+
+ bio_list_init(&bio_list_on_stack);
+
+ throtl_log(td, "dispatch nr_queued=%lu read=%u write=%u",
+ total_nr_queued(td), td->nr_queued[READ],
+ td->nr_queued[WRITE]);
+
+ nr_disp = throtl_select_dispatch(td, &bio_list_on_stack);
+
+ if (nr_disp)
+ throtl_log(td, "bios disp=%u", nr_disp);
+
+ throtl_schedule_next_dispatch(td);
+out:
+ spin_unlock_irq(q->queue_lock);
+
+ /*
+ * If we dispatched some requests, unplug the queue to make sure
+ * immediate dispatch
+ */
+ if (nr_disp) {
+ while((bio = bio_list_pop(&bio_list_on_stack)))
+ generic_make_request(bio);
+ blk_unplug(q);
+ }
+ return nr_disp;
+}
+
+void blk_throtl_work(struct work_struct *work)
+{
+ struct throtl_data *td = container_of(work, struct throtl_data,
+ throtl_work.work);
+ struct request_queue *q = td->queue;
+
+ throtl_dispatch(q);
+}
+
+/* Call with queue lock held */
+void throtl_schedule_delayed_work(struct request_queue *q, unsigned long delay)
+{
+
+ struct throtl_data *td = q->td;
+ struct delayed_work *dwork = &td->throtl_work;
+
+ if (total_nr_queued(td) > 0) {
+ /*
+ * We might have a work scheduled to be executed in future.
+ * Cancel that and schedule a new one.
+ */
+ __cancel_delayed_work(dwork);
+ kblockd_schedule_delayed_work(q, dwork, delay);
+ throtl_log(td, "schedule work. delay=%lu jiffies=%lu",
+ delay, jiffies);
+ }
+}
+EXPORT_SYMBOL(throtl_schedule_delayed_work);
+
+static void
+throtl_destroy_tg(struct throtl_data *td, struct throtl_grp *tg)
+{
+ /* Something wrong if we are trying to remove same group twice */
+ BUG_ON(hlist_unhashed(&tg->tg_node));
+
+ hlist_del_init(&tg->tg_node);
+
+ /*
+ * Put the reference taken at the time of creation so that when all
+ * queues are gone, group can be destroyed.
+ */
+ throtl_put_tg(tg);
+ td->nr_undestroyed_grps--;
+}
+
+static void throtl_release_tgs(struct throtl_data *td)
+{
+ struct hlist_node *pos, *n;
+ struct throtl_grp *tg;
+
+ hlist_for_each_entry_safe(tg, pos, n, &td->tg_list, tg_node) {
+ /*
+ * If cgroup removal path got to blk_group first and removed
+ * it from cgroup list, then it will take care of destroying
+ * cfqg also.
+ */
+ if (!blkiocg_del_blkio_group(&tg->blkg))
+ throtl_destroy_tg(td, tg);
+ }
+}
+
+static void throtl_td_free(struct throtl_data *td)
+{
+ kfree(td);
+}
+
+/*
+ * Blk cgroup controller notification saying that blkio_group object is being
+ * delinked as associated cgroup object is going away. That also means that
+ * no new IO will come in this group. So get rid of this group as soon as
+ * any pending IO in the group is finished.
+ *
+ * This function is called under rcu_read_lock(). key is the rcu protected
+ * pointer. That means "key" is a valid throtl_data pointer as long as we are
+ * rcu read lock.
+ *
+ * "key" was fetched from blkio_group under blkio_cgroup->lock. That means
+ * it should not be NULL as even if queue was going away, cgroup deltion
+ * path got to it first.
+ */
+void throtl_unlink_blkio_group(void *key, struct blkio_group *blkg)
+{
+ unsigned long flags;
+ struct throtl_data *td = key;
+
+ spin_lock_irqsave(td->queue->queue_lock, flags);
+ throtl_destroy_tg(td, tg_of_blkg(blkg));
+ spin_unlock_irqrestore(td->queue->queue_lock, flags);
+}
+
+/*
+ * For all update functions, key should be a valid pointer because these
+ * update functions are called under blkcg_lock, that means, blkg is
+ * valid and in turn key is valid. queue exit path can not race becuase
+ * of blkcg_lock
+ *
+ * Can not take queue lock in update functions as queue lock under blkcg_lock
+ * is not allowed. Under other paths we take blkcg_lock under queue_lock.
+ */
+static void throtl_update_blkio_group_read_bps(void *key,
+ struct blkio_group *blkg, u64 read_bps)
+{
+ struct throtl_data *td = key;
+
+ tg_of_blkg(blkg)->bps[READ] = read_bps;
+ /* Make sure read_bps is updated before setting limits_changed */
+ smp_wmb();
+ tg_of_blkg(blkg)->limits_changed = true;
+
+ /* Make sure tg->limits_changed is updated before td->limits_changed */
+ smp_mb__before_atomic_inc();
+ atomic_inc(&td->limits_changed);
+ smp_mb__after_atomic_inc();
+
+ /* Schedule a work now to process the limit change */
+ throtl_schedule_delayed_work(td->queue, 0);
+}
+
+static void throtl_update_blkio_group_write_bps(void *key,
+ struct blkio_group *blkg, u64 write_bps)
+{
+ struct throtl_data *td = key;
+
+ tg_of_blkg(blkg)->bps[WRITE] = write_bps;
+ smp_wmb();
+ tg_of_blkg(blkg)->limits_changed = true;
+ smp_mb__before_atomic_inc();
+ atomic_inc(&td->limits_changed);
+ smp_mb__after_atomic_inc();
+ throtl_schedule_delayed_work(td->queue, 0);
+}
+
+static void throtl_update_blkio_group_read_iops(void *key,
+ struct blkio_group *blkg, unsigned int read_iops)
+{
+ struct throtl_data *td = key;
+
+ tg_of_blkg(blkg)->iops[READ] = read_iops;
+ smp_wmb();
+ tg_of_blkg(blkg)->limits_changed = true;
+ smp_mb__before_atomic_inc();
+ atomic_inc(&td->limits_changed);
+ smp_mb__after_atomic_inc();
+ throtl_schedule_delayed_work(td->queue, 0);
+}
+
+static void throtl_update_blkio_group_write_iops(void *key,
+ struct blkio_group *blkg, unsigned int write_iops)
+{
+ struct throtl_data *td = key;
+
+ tg_of_blkg(blkg)->iops[WRITE] = write_iops;
+ smp_wmb();
+ tg_of_blkg(blkg)->limits_changed = true;
+ smp_mb__before_atomic_inc();
+ atomic_inc(&td->limits_changed);
+ smp_mb__after_atomic_inc();
+ throtl_schedule_delayed_work(td->queue, 0);
+}
+
+void throtl_shutdown_timer_wq(struct request_queue *q)
+{
+ struct throtl_data *td = q->td;
+
+ cancel_delayed_work_sync(&td->throtl_work);
+}
+
+static struct blkio_policy_type blkio_policy_throtl = {
+ .ops = {
+ .blkio_unlink_group_fn = throtl_unlink_blkio_group,
+ .blkio_update_group_read_bps_fn =
+ throtl_update_blkio_group_read_bps,
+ .blkio_update_group_write_bps_fn =
+ throtl_update_blkio_group_write_bps,
+ .blkio_update_group_read_iops_fn =
+ throtl_update_blkio_group_read_iops,
+ .blkio_update_group_write_iops_fn =
+ throtl_update_blkio_group_write_iops,
+ },
+ .plid = BLKIO_POLICY_THROTL,
+};
+
+int blk_throtl_bio(struct request_queue *q, struct bio **biop)
+{
+ struct throtl_data *td = q->td;
+ struct throtl_grp *tg;
+ struct bio *bio = *biop;
+ bool rw = bio_data_dir(bio), update_disptime = true;
+
+ if (bio->bi_rw & REQ_THROTTLED) {
+ bio->bi_rw &= ~REQ_THROTTLED;
+ return 0;
+ }
+
+ spin_lock_irq(q->queue_lock);
+ tg = throtl_get_tg(td);
+
+ if (tg->nr_queued[rw]) {
+ /*
+ * There is already another bio queued in same dir. No
+ * need to update dispatch time.
+ * Still update the disptime if rate limits on this group
+ * were changed.
+ */
+ if (!tg->limits_changed)
+ update_disptime = false;
+ else
+ tg->limits_changed = false;
+
+ goto queue_bio;
+ }
+
+ /* Bio is with-in rate limit of group */
+ if (tg_may_dispatch(td, tg, bio, NULL)) {
+ throtl_charge_bio(tg, bio);
+ goto out;
+ }
+
+queue_bio:
+ throtl_log_tg(td, tg, "[%c] bio. bdisp=%u sz=%u bps=%llu"
+ " iodisp=%u iops=%u queued=%d/%d",
+ rw == READ ? 'R' : 'W',
+ tg->bytes_disp[rw], bio->bi_size, tg->bps[rw],
+ tg->io_disp[rw], tg->iops[rw],
+ tg->nr_queued[READ], tg->nr_queued[WRITE]);
+
+ throtl_add_bio_tg(q->td, tg, bio);
+ *biop = NULL;
+
+ if (update_disptime) {
+ tg_update_disptime(td, tg);
+ throtl_schedule_next_dispatch(td);
+ }
+
+out:
+ spin_unlock_irq(q->queue_lock);
+ return 0;
+}
+
+int blk_throtl_init(struct request_queue *q)
+{
+ struct throtl_data *td;
+ struct throtl_grp *tg;
+
+ td = kzalloc_node(sizeof(*td), GFP_KERNEL, q->node);
+ if (!td)
+ return -ENOMEM;
+
+ INIT_HLIST_HEAD(&td->tg_list);
+ td->tg_service_tree = THROTL_RB_ROOT;
+ atomic_set(&td->limits_changed, 0);
+
+ /* Init root group */
+ tg = &td->root_tg;
+ INIT_HLIST_NODE(&tg->tg_node);
+ RB_CLEAR_NODE(&tg->rb_node);
+ bio_list_init(&tg->bio_lists[0]);
+ bio_list_init(&tg->bio_lists[1]);
+
+ /* Practically unlimited BW */
+ tg->bps[0] = tg->bps[1] = -1;
+ tg->iops[0] = tg->iops[1] = -1;
+
+ /*
+ * Set root group reference to 2. One reference will be dropped when
+ * all groups on tg_list are being deleted during queue exit. Other
+ * reference will remain there as we don't want to delete this group
+ * as it is statically allocated and gets destroyed when throtl_data
+ * goes away.
+ */
+ atomic_set(&tg->ref, 2);
+ hlist_add_head(&tg->tg_node, &td->tg_list);
+ td->nr_undestroyed_grps++;
+
+ INIT_DELAYED_WORK(&td->throtl_work, blk_throtl_work);
+
+ rcu_read_lock();
+ blkiocg_add_blkio_group(&blkio_root_cgroup, &tg->blkg, (void *)td,
+ 0, BLKIO_POLICY_THROTL);
+ rcu_read_unlock();
+
+ /* Attach throtl data to request queue */
+ td->queue = q;
+ q->td = td;
+ return 0;
+}
+
+void blk_throtl_exit(struct request_queue *q)
+{
+ struct throtl_data *td = q->td;
+ bool wait = false;
+
+ BUG_ON(!td);
+
+ throtl_shutdown_timer_wq(q);
+
+ spin_lock_irq(q->queue_lock);
+ throtl_release_tgs(td);
+
+ /* If there are other groups */
+ if (td->nr_undestroyed_grps > 0)
+ wait = true;
+
+ spin_unlock_irq(q->queue_lock);
+
+ /*
+ * Wait for tg->blkg->key accessors to exit their grace periods.
+ * Do this wait only if there are other undestroyed groups out
+ * there (other than root group). This can happen if cgroup deletion
+ * path claimed the responsibility of cleaning up a group before
+ * queue cleanup code get to the group.
+ *
+ * Do not call synchronize_rcu() unconditionally as there are drivers
+ * which create/delete request queue hundreds of times during scan/boot
+ * and synchronize_rcu() can take significant time and slow down boot.
+ */
+ if (wait)
+ synchronize_rcu();
+
+ /*
+ * Just being safe to make sure after previous flush if some body did
+ * update limits through cgroup and another work got queued, cancel
+ * it.
+ */
+ throtl_shutdown_timer_wq(q);
+ throtl_td_free(td);
+}
+
+static int __init throtl_init(void)
+{
+ blkio_policy_register(&blkio_policy_throtl);
+ return 0;
+}
+
+module_init(throtl_init);
diff --git a/block/blk.h b/block/blk.h
index d6b911ac002..f864012ec30 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -110,10 +110,6 @@ void blk_queue_congestion_threshold(struct request_queue *q);
int blk_dev_init(void);
-void elv_quiesce_start(struct request_queue *q);
-void elv_quiesce_end(struct request_queue *q);
-
-
/*
* Return the threshold (number of used requests) at which the queue is
* considered to be congested. It include a little hysteresis to keep the
@@ -132,14 +128,6 @@ static inline int queue_congestion_off_threshold(struct request_queue *q)
return q->nr_congestion_off;
}
-#if defined(CONFIG_BLK_DEV_INTEGRITY)
-
-#define rq_for_each_integrity_segment(bvl, _rq, _iter) \
- __rq_for_each_bio(_iter.bio, _rq) \
- bip_for_each_vec(bvl, _iter.bio->bi_integrity, _iter.i)
-
-#endif /* BLK_DEV_INTEGRITY */
-
static inline int blk_cpu_to_group(int cpu)
{
int group = NR_CPUS;
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 9eba291eb6f..4cd59b0d7c1 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -160,6 +160,7 @@ enum wl_prio_t {
BE_WORKLOAD = 0,
RT_WORKLOAD = 1,
IDLE_WORKLOAD = 2,
+ CFQ_PRIO_NR,
};
/*
@@ -184,10 +185,19 @@ struct cfq_group {
/* number of cfqq currently on this group */
int nr_cfqq;
- /* Per group busy queus average. Useful for workload slice calc. */
- unsigned int busy_queues_avg[2];
/*
- * rr lists of queues with requests, onle rr for each priority class.
+ * Per group busy queus average. Useful for workload slice calc. We
+ * create the array for each prio class but at run time it is used
+ * only for RT and BE class and slot for IDLE class remains unused.
+ * This is primarily done to avoid confusion and a gcc warning.
+ */
+ unsigned int busy_queues_avg[CFQ_PRIO_NR];
+ /*
+ * rr lists of queues with requests. We maintain service trees for
+ * RT and BE classes. These trees are subdivided in subclasses
+ * of SYNC, SYNC_NOIDLE and ASYNC based on workload type. For IDLE
+ * class there is no subclassification and all the cfq queues go on
+ * a single tree service_tree_idle.
* Counts are embedded in the cfq_rb_root
*/
struct cfq_rb_root service_trees[2][3];
@@ -221,7 +231,6 @@ struct cfq_data {
enum wl_type_t serving_type;
unsigned long workload_expires;
struct cfq_group *serving_group;
- bool noidle_tree_requires_idle;
/*
* Each priority tree is sorted by next_request position. These
@@ -977,8 +986,8 @@ static inline struct cfq_group *cfqg_of_blkg(struct blkio_group *blkg)
return NULL;
}
-void
-cfq_update_blkio_group_weight(struct blkio_group *blkg, unsigned int weight)
+void cfq_update_blkio_group_weight(void *key, struct blkio_group *blkg,
+ unsigned int weight)
{
cfqg_of_blkg(blkg)->weight = weight;
}
@@ -2180,7 +2189,6 @@ static void choose_service_tree(struct cfq_data *cfqd, struct cfq_group *cfqg)
slice = max_t(unsigned, slice, CFQ_MIN_TT);
cfq_log(cfqd, "workload slice:%d", slice);
cfqd->workload_expires = jiffies + slice;
- cfqd->noidle_tree_requires_idle = false;
}
static struct cfq_group *cfq_get_next_cfqg(struct cfq_data *cfqd)
@@ -3177,7 +3185,9 @@ cfq_update_idle_window(struct cfq_data *cfqd, struct cfq_queue *cfqq,
if (cfqq->queued[0] + cfqq->queued[1] >= 4)
cfq_mark_cfqq_deep(cfqq);
- if (!atomic_read(&cic->ioc->nr_tasks) || !cfqd->cfq_slice_idle ||
+ if (cfqq->next_rq && (cfqq->next_rq->cmd_flags & REQ_NOIDLE))
+ enable_idle = 0;
+ else if (!atomic_read(&cic->ioc->nr_tasks) || !cfqd->cfq_slice_idle ||
(!cfq_cfqq_deep(cfqq) && CFQQ_SEEKY(cfqq)))
enable_idle = 0;
else if (sample_valid(cic->ttime_samples)) {
@@ -3494,17 +3504,7 @@ static void cfq_completed_request(struct request_queue *q, struct request *rq)
cfq_slice_expired(cfqd, 1);
else if (sync && cfqq_empty &&
!cfq_close_cooperator(cfqd, cfqq)) {
- cfqd->noidle_tree_requires_idle |=
- !(rq->cmd_flags & REQ_NOIDLE);
- /*
- * Idling is enabled for SYNC_WORKLOAD.
- * SYNC_NOIDLE_WORKLOAD idles at the end of the tree
- * only if we processed at least one !REQ_NOIDLE request
- */
- if (cfqd->serving_type == SYNC_WORKLOAD
- || cfqd->noidle_tree_requires_idle
- || cfqq->cfqg->nr_cfqq == 1)
- cfq_arm_slice_timer(cfqd);
+ cfq_arm_slice_timer(cfqd);
}
}
@@ -4090,6 +4090,7 @@ static struct blkio_policy_type blkio_policy_cfq = {
.blkio_unlink_group_fn = cfq_unlink_blkio_group,
.blkio_update_group_weight_fn = cfq_update_blkio_group_weight,
},
+ .plid = BLKIO_POLICY_PROP,
};
#else
static struct blkio_policy_type blkio_policy_cfq;
diff --git a/block/cfq.h b/block/cfq.h
index 93448e5a2e4..54a6d90f8e8 100644
--- a/block/cfq.h
+++ b/block/cfq.h
@@ -69,7 +69,7 @@ static inline void cfq_blkiocg_update_completion_stats(struct blkio_group *blkg,
static inline void cfq_blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
struct blkio_group *blkg, void *key, dev_t dev) {
- blkiocg_add_blkio_group(blkcg, blkg, key, dev);
+ blkiocg_add_blkio_group(blkcg, blkg, key, dev, BLKIO_POLICY_PROP);
}
static inline int cfq_blkiocg_del_blkio_group(struct blkio_group *blkg)
diff --git a/block/genhd.c b/block/genhd.c
index 59a2db6fece..8313834596d 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -541,13 +541,15 @@ void add_disk(struct gendisk *disk)
disk->major = MAJOR(devt);
disk->first_minor = MINOR(devt);
+ /* Register BDI before referencing it from bdev */
+ bdi = &disk->queue->backing_dev_info;
+ bdi_register_dev(bdi, disk_devt(disk));
+
blk_register_region(disk_devt(disk), disk->minors, NULL,
exact_match, exact_lock, disk);
register_disk(disk);
blk_register_queue(disk);
- bdi = &disk->queue->backing_dev_info;
- bdi_register_dev(bdi, disk_devt(disk));
retval = sysfs_create_link(&disk_to_dev(disk)->kobj, &bdi->dev->kobj,
"bdi");
WARN_ON(retval);
@@ -642,6 +644,7 @@ void __init printk_all_partitions(void)
struct hd_struct *part;
char name_buf[BDEVNAME_SIZE];
char devt_buf[BDEVT_SIZE];
+ u8 uuid[PARTITION_META_INFO_UUIDLTH * 2 + 1];
/*
* Don't show empty devices or things that have been
@@ -660,10 +663,14 @@ void __init printk_all_partitions(void)
while ((part = disk_part_iter_next(&piter))) {
bool is_part0 = part == &disk->part0;
- printk("%s%s %10llu %s", is_part0 ? "" : " ",
+ uuid[0] = 0;
+ if (part->info)
+ part_unpack_uuid(part->info->uuid, uuid);
+
+ printk("%s%s %10llu %s %s", is_part0 ? "" : " ",
bdevt_str(part_devt(part), devt_buf),
(unsigned long long)part->nr_sects >> 1,
- disk_name(disk, part->partno, name_buf));
+ disk_name(disk, part->partno, name_buf), uuid);
if (is_part0) {
if (disk->driverfs_dev != NULL &&
disk->driverfs_dev->driver != NULL)
@@ -925,8 +932,15 @@ static void disk_free_ptbl_rcu_cb(struct rcu_head *head)
{
struct disk_part_tbl *ptbl =
container_of(head, struct disk_part_tbl, rcu_head);
+ struct gendisk *disk = ptbl->disk;
+ struct request_queue *q = disk->queue;
+ unsigned long flags;
kfree(ptbl);
+
+ spin_lock_irqsave(q->queue_lock, flags);
+ elv_quiesce_end(q);
+ spin_unlock_irqrestore(q->queue_lock, flags);
}
/**
@@ -944,11 +958,17 @@ static void disk_replace_part_tbl(struct gendisk *disk,
struct disk_part_tbl *new_ptbl)
{
struct disk_part_tbl *old_ptbl = disk->part_tbl;
+ struct request_queue *q = disk->queue;
rcu_assign_pointer(disk->part_tbl, new_ptbl);
if (old_ptbl) {
rcu_assign_pointer(old_ptbl->last_lookup, NULL);
+
+ spin_lock_irq(q->queue_lock);
+ elv_quiesce_start(q);
+ spin_unlock_irq(q->queue_lock);
+
call_rcu(&old_ptbl->rcu_head, disk_free_ptbl_rcu_cb);
}
}
@@ -989,6 +1009,7 @@ int disk_expand_part_tbl(struct gendisk *disk, int partno)
return -ENOMEM;
new_ptbl->len = target;
+ new_ptbl->disk = disk;
for (i = 0; i < len; i++)
rcu_assign_pointer(new_ptbl->part[i], old_ptbl->part[i]);
@@ -1004,6 +1025,7 @@ static void disk_release(struct device *dev)
kfree(disk->random);
disk_replace_part_tbl(disk, NULL);
free_part_stats(&disk->part0);
+ free_part_info(&disk->part0);
kfree(disk);
}
struct class block_class = {
diff --git a/block/ioctl.c b/block/ioctl.c
index d8052f0dabd..2c15fe0912c 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -62,7 +62,7 @@ static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user
/* all seems OK */
part = add_partition(disk, partno, start, length,
- ADDPART_FLAG_NONE);
+ ADDPART_FLAG_NONE, NULL);
mutex_unlock(&bdev->bd_mutex);
return IS_ERR(part) ? PTR_ERR(part) : 0;
case BLKPG_DEL_PARTITION: