struct blkio_cgroup blkio_root_cgroup = { .weight = 2*BLKIO_WEIGHT_DEFAULT };
EXPORT_SYMBOL_GPL(blkio_root_cgroup);
-static struct cgroup_subsys_state *blkiocg_create(struct cgroup_subsys *,
- struct cgroup *);
-static int blkiocg_can_attach(struct cgroup_subsys *, struct cgroup *,
- struct task_struct *, bool);
-static void blkiocg_attach(struct cgroup_subsys *, struct cgroup *,
- struct cgroup *, struct task_struct *, bool);
-static void blkiocg_destroy(struct cgroup_subsys *, struct cgroup *);
+static struct cgroup_subsys_state *blkiocg_create(struct cgroup *);
+static int blkiocg_can_attach(struct cgroup *, struct cgroup_taskset *);
+static void blkiocg_attach(struct cgroup *, struct cgroup_taskset *);
+static void blkiocg_destroy(struct cgroup *);
static int blkiocg_populate(struct cgroup_subsys *, struct cgroup *);
/* for encoding cft->private value on file */
}
EXPORT_SYMBOL_GPL(cgroup_to_blkio_cgroup);
+struct blkio_cgroup *task_blkio_cgroup(struct task_struct *tsk)
+{
+ return container_of(task_subsys_state(tsk, blkio_subsys_id),
+ struct blkio_cgroup, css);
+}
+EXPORT_SYMBOL_GPL(task_blkio_cgroup);
+
static inline void
blkio_update_group_weight(struct blkio_group *blkg, unsigned int weight)
{
spin_lock_irqsave(&blkg->stats_lock, flags);
blkg->stats.time += time;
+#ifdef CONFIG_DEBUG_BLK_CGROUP
blkg->stats.unaccounted_time += unaccounted_time;
+#endif
spin_unlock_irqrestore(&blkg->stats_lock, flags);
}
EXPORT_SYMBOL_GPL(blkiocg_update_timeslice_used);
+/*
+ * should be called under rcu read lock or queue lock to make sure blkg pointer
+ * is valid.
+ */
void blkiocg_update_dispatch_stats(struct blkio_group *blkg,
uint64_t bytes, bool direction, bool sync)
{
- struct blkio_group_stats *stats;
+ struct blkio_group_stats_cpu *stats_cpu;
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);
+ /*
+ * Disabling interrupts to provide mutual exclusion between two
+ * writes on same cpu. It probably is not needed for 64bit. Not
+ * optimizing that case yet.
+ */
+ local_irq_save(flags);
+
+ stats_cpu = this_cpu_ptr(blkg->stats_cpu);
+
+ u64_stats_update_begin(&stats_cpu->syncp);
+ stats_cpu->sectors += bytes >> 9;
+ blkio_add_stat(stats_cpu->stat_arr_cpu[BLKIO_STAT_CPU_SERVICED],
+ 1, direction, sync);
+ blkio_add_stat(stats_cpu->stat_arr_cpu[BLKIO_STAT_CPU_SERVICE_BYTES],
+ bytes, direction, sync);
+ u64_stats_update_end(&stats_cpu->syncp);
+ local_irq_restore(flags);
}
EXPORT_SYMBOL_GPL(blkiocg_update_dispatch_stats);
}
EXPORT_SYMBOL_GPL(blkiocg_update_completion_stats);
+/* Merged stats are per cpu. */
void blkiocg_update_io_merged_stats(struct blkio_group *blkg, bool direction,
bool sync)
{
+ struct blkio_group_stats_cpu *stats_cpu;
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);
+ /*
+ * Disabling interrupts to provide mutual exclusion between two
+ * writes on same cpu. It probably is not needed for 64bit. Not
+ * optimizing that case yet.
+ */
+ local_irq_save(flags);
+
+ stats_cpu = this_cpu_ptr(blkg->stats_cpu);
+
+ u64_stats_update_begin(&stats_cpu->syncp);
+ blkio_add_stat(stats_cpu->stat_arr_cpu[BLKIO_STAT_CPU_MERGED], 1,
+ direction, sync);
+ u64_stats_update_end(&stats_cpu->syncp);
+ local_irq_restore(flags);
}
EXPORT_SYMBOL_GPL(blkiocg_update_io_merged_stats);
+/*
+ * This function allocates the per cpu stats for blkio_group. Should be called
+ * from sleepable context as alloc_per_cpu() requires that.
+ */
+int blkio_alloc_blkg_stats(struct blkio_group *blkg)
+{
+ /* Allocate memory for per cpu stats */
+ blkg->stats_cpu = alloc_percpu(struct blkio_group_stats_cpu);
+ if (!blkg->stats_cpu)
+ return -ENOMEM;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(blkio_alloc_blkg_stats);
+
void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
struct blkio_group *blkg, void *key, dev_t dev,
enum blkio_policy_id plid)
}
EXPORT_SYMBOL_GPL(blkiocg_lookup_group);
+static void blkio_reset_stats_cpu(struct blkio_group *blkg)
+{
+ struct blkio_group_stats_cpu *stats_cpu;
+ int i, j, k;
+ /*
+ * Note: On 64 bit arch this should not be an issue. This has the
+ * possibility of returning some inconsistent value on 32bit arch
+ * as 64bit update on 32bit is non atomic. Taking care of this
+ * corner case makes code very complicated, like sending IPIs to
+ * cpus, taking care of stats of offline cpus etc.
+ *
+ * reset stats is anyway more of a debug feature and this sounds a
+ * corner case. So I am not complicating the code yet until and
+ * unless this becomes a real issue.
+ */
+ for_each_possible_cpu(i) {
+ stats_cpu = per_cpu_ptr(blkg->stats_cpu, i);
+ stats_cpu->sectors = 0;
+ for(j = 0; j < BLKIO_STAT_CPU_NR; j++)
+ for (k = 0; k < BLKIO_STAT_TOTAL; k++)
+ stats_cpu->stat_arr_cpu[j][k] = 0;
+ }
+}
+
static int
blkiocg_reset_stats(struct cgroup *cgroup, struct cftype *cftype, u64 val)
{
}
#endif
spin_unlock(&blkg->stats_lock);
+
+ /* Reset Per cpu stats which don't take blkg->stats_lock */
+ blkio_reset_stats_cpu(blkg);
}
+
spin_unlock_irq(&blkcg->lock);
return 0;
}
return val;
}
+
+static uint64_t blkio_read_stat_cpu(struct blkio_group *blkg,
+ enum stat_type_cpu type, enum stat_sub_type sub_type)
+{
+ int cpu;
+ struct blkio_group_stats_cpu *stats_cpu;
+ u64 val = 0, tval;
+
+ for_each_possible_cpu(cpu) {
+ unsigned int start;
+ stats_cpu = per_cpu_ptr(blkg->stats_cpu, cpu);
+
+ do {
+ start = u64_stats_fetch_begin(&stats_cpu->syncp);
+ if (type == BLKIO_STAT_CPU_SECTORS)
+ tval = stats_cpu->sectors;
+ else
+ tval = stats_cpu->stat_arr_cpu[type][sub_type];
+ } while(u64_stats_fetch_retry(&stats_cpu->syncp, start));
+
+ val += tval;
+ }
+
+ return val;
+}
+
+static uint64_t blkio_get_stat_cpu(struct blkio_group *blkg,
+ struct cgroup_map_cb *cb, dev_t dev, enum stat_type_cpu type)
+{
+ uint64_t disk_total, val;
+ char key_str[MAX_KEY_LEN];
+ enum stat_sub_type sub_type;
+
+ if (type == BLKIO_STAT_CPU_SECTORS) {
+ val = blkio_read_stat_cpu(blkg, type, 0);
+ return blkio_fill_stat(key_str, MAX_KEY_LEN - 1, val, cb, dev);
+ }
+
+ 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);
+ val = blkio_read_stat_cpu(blkg, type, sub_type);
+ cb->fill(cb, key_str, val);
+ }
+
+ disk_total = blkio_read_stat_cpu(blkg, type, BLKIO_STAT_READ) +
+ blkio_read_stat_cpu(blkg, 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;
+}
+
/* 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)
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_UNACCOUNTED_TIME)
return blkio_fill_stat(key_str, MAX_KEY_LEN - 1,
blkg->stats.unaccounted_time, 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;
return disk_total;
}
-static int blkio_check_dev_num(dev_t dev)
-{
- int part = 0;
- struct gendisk *disk;
-
- disk = get_gendisk(dev, &part);
- if (!disk || part)
- return -ENODEV;
-
- return 0;
-}
-
static int blkio_policy_parse_and_set(char *buf,
struct blkio_policy_node *newpn, enum blkio_policy_id plid, int fileid)
{
+ struct gendisk *disk = NULL;
char *s[4], *p, *major_s = NULL, *minor_s = NULL;
- int ret;
- unsigned long major, minor, temp;
- int i = 0;
+ unsigned long major, minor;
+ int i = 0, ret = -EINVAL;
+ int part;
dev_t dev;
- u64 bps, iops;
+ u64 temp;
memset(s, 0, sizeof(s));
}
if (i != 2)
- return -EINVAL;
+ goto out;
p = strsep(&s[0], ":");
if (p != NULL)
major_s = p;
else
- return -EINVAL;
+ goto out;
minor_s = s[0];
if (!minor_s)
- return -EINVAL;
+ goto out;
- ret = strict_strtoul(major_s, 10, &major);
- if (ret)
- return -EINVAL;
+ if (strict_strtoul(major_s, 10, &major))
+ goto out;
- ret = strict_strtoul(minor_s, 10, &minor);
- if (ret)
- return -EINVAL;
+ if (strict_strtoul(minor_s, 10, &minor))
+ goto out;
dev = MKDEV(major, minor);
- ret = blkio_check_dev_num(dev);
- if (ret)
- return ret;
+ if (strict_strtoull(s[1], 10, &temp))
+ goto out;
- newpn->dev = dev;
+ /* For rule removal, do not check for device presence. */
+ if (temp) {
+ disk = get_gendisk(dev, &part);
+ if (!disk || part) {
+ ret = -ENODEV;
+ goto out;
+ }
+ }
- if (s[1] == NULL)
- return -EINVAL;
+ newpn->dev = dev;
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;
+ if ((temp < BLKIO_WEIGHT_MIN && temp > 0) ||
+ temp > BLKIO_WEIGHT_MAX)
+ goto out;
newpn->plid = plid;
newpn->fileid = fileid;
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;
+ newpn->val.bps = temp;
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;
+ if (temp > THROTL_IOPS_MAX)
+ goto out;
newpn->plid = plid;
newpn->fileid = fileid;
- newpn->val.iops = (unsigned int)iops;
+ newpn->val.iops = (unsigned int)temp;
break;
}
break;
default:
BUG();
}
-
- return 0;
+ ret = 0;
+out:
+ put_disk(disk);
+ return ret;
}
unsigned int blkcg_get_weight(struct blkio_cgroup *blkcg,
dev_t dev)
{
struct blkio_policy_node *pn;
+ unsigned long flags;
+ unsigned int weight;
+
+ spin_lock_irqsave(&blkcg->lock, flags);
pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_PROP,
BLKIO_PROP_weight_device);
if (pn)
- return pn->val.weight;
+ weight = pn->val.weight;
else
- return blkcg->weight;
+ weight = blkcg->weight;
+
+ spin_unlock_irqrestore(&blkcg->lock, flags);
+
+ return 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;
+ unsigned long flags;
+ uint64_t bps = -1;
+ spin_lock_irqsave(&blkcg->lock, flags);
pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL,
BLKIO_THROTL_read_bps_device);
if (pn)
- return pn->val.bps;
- else
- return -1;
+ bps = pn->val.bps;
+ spin_unlock_irqrestore(&blkcg->lock, flags);
+
+ return bps;
}
uint64_t blkcg_get_write_bps(struct blkio_cgroup *blkcg, dev_t dev)
{
struct blkio_policy_node *pn;
+ unsigned long flags;
+ uint64_t bps = -1;
+
+ spin_lock_irqsave(&blkcg->lock, flags);
pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL,
BLKIO_THROTL_write_bps_device);
if (pn)
- return pn->val.bps;
- else
- return -1;
+ bps = pn->val.bps;
+ spin_unlock_irqrestore(&blkcg->lock, flags);
+
+ return bps;
}
unsigned int blkcg_get_read_iops(struct blkio_cgroup *blkcg, dev_t dev)
{
struct blkio_policy_node *pn;
+ unsigned long flags;
+ unsigned int iops = -1;
+ spin_lock_irqsave(&blkcg->lock, flags);
pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL,
BLKIO_THROTL_read_iops_device);
if (pn)
- return pn->val.iops;
- else
- return -1;
+ iops = pn->val.iops;
+ spin_unlock_irqrestore(&blkcg->lock, flags);
+
+ return iops;
}
unsigned int blkcg_get_write_iops(struct blkio_cgroup *blkcg, dev_t dev)
{
struct blkio_policy_node *pn;
+ unsigned long flags;
+ unsigned int iops = -1;
+
+ spin_lock_irqsave(&blkcg->lock, flags);
pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL,
BLKIO_THROTL_write_iops_device);
if (pn)
- return pn->val.iops;
- else
- return -1;
+ iops = pn->val.iops;
+ spin_unlock_irqrestore(&blkcg->lock, flags);
+
+ return iops;
}
/* Checks whether user asked for deleting a policy rule */
}
/*
- * Some rules/values in blkg have changed. Propogate those to respective
+ * Some rules/values in blkg have changed. Propagate those to respective
* policies.
*/
static void blkio_update_blkg_policy(struct blkio_cgroup *blkcg,
}
/*
- * A policy node rule has been updated. Propogate this update to all the
+ * A policy node rule has been updated. Propagate 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,
if (blkio_delete_rule_command(newpn)) {
blkio_policy_delete_node(pn);
+ kfree(pn);
spin_unlock_irq(&blkcg->lock);
goto update_io_group;
}
}
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 cftype *cft, struct cgroup_map_cb *cb,
+ enum stat_type type, bool show_total, bool pcpu)
{
struct blkio_group *blkg;
struct hlist_node *n;
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 (pcpu)
+ cgroup_total += blkio_get_stat_cpu(blkg, cb,
+ blkg->dev, type);
+ else {
+ 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)
switch(name) {
case BLKIO_PROP_time:
return blkio_read_blkg_stats(blkcg, cft, cb,
- BLKIO_STAT_TIME, 0);
+ BLKIO_STAT_TIME, 0, 0);
case BLKIO_PROP_sectors:
return blkio_read_blkg_stats(blkcg, cft, cb,
- BLKIO_STAT_SECTORS, 0);
- case BLKIO_PROP_unaccounted_time:
- return blkio_read_blkg_stats(blkcg, cft, cb,
- BLKIO_STAT_UNACCOUNTED_TIME, 0);
+ BLKIO_STAT_CPU_SECTORS, 0, 1);
case BLKIO_PROP_io_service_bytes:
return blkio_read_blkg_stats(blkcg, cft, cb,
- BLKIO_STAT_SERVICE_BYTES, 1);
+ BLKIO_STAT_CPU_SERVICE_BYTES, 1, 1);
case BLKIO_PROP_io_serviced:
return blkio_read_blkg_stats(blkcg, cft, cb,
- BLKIO_STAT_SERVICED, 1);
+ BLKIO_STAT_CPU_SERVICED, 1, 1);
case BLKIO_PROP_io_service_time:
return blkio_read_blkg_stats(blkcg, cft, cb,
- BLKIO_STAT_SERVICE_TIME, 1);
+ BLKIO_STAT_SERVICE_TIME, 1, 0);
case BLKIO_PROP_io_wait_time:
return blkio_read_blkg_stats(blkcg, cft, cb,
- BLKIO_STAT_WAIT_TIME, 1);
+ BLKIO_STAT_WAIT_TIME, 1, 0);
case BLKIO_PROP_io_merged:
return blkio_read_blkg_stats(blkcg, cft, cb,
- BLKIO_STAT_MERGED, 1);
+ BLKIO_STAT_CPU_MERGED, 1, 1);
case BLKIO_PROP_io_queued:
return blkio_read_blkg_stats(blkcg, cft, cb,
- BLKIO_STAT_QUEUED, 1);
+ BLKIO_STAT_QUEUED, 1, 0);
#ifdef CONFIG_DEBUG_BLK_CGROUP
+ case BLKIO_PROP_unaccounted_time:
+ return blkio_read_blkg_stats(blkcg, cft, cb,
+ BLKIO_STAT_UNACCOUNTED_TIME, 0, 0);
case BLKIO_PROP_dequeue:
return blkio_read_blkg_stats(blkcg, cft, cb,
- BLKIO_STAT_DEQUEUE, 0);
+ BLKIO_STAT_DEQUEUE, 0, 0);
case BLKIO_PROP_avg_queue_size:
return blkio_read_blkg_stats(blkcg, cft, cb,
- BLKIO_STAT_AVG_QUEUE_SIZE, 0);
+ BLKIO_STAT_AVG_QUEUE_SIZE, 0, 0);
case BLKIO_PROP_group_wait_time:
return blkio_read_blkg_stats(blkcg, cft, cb,
- BLKIO_STAT_GROUP_WAIT_TIME, 0);
+ BLKIO_STAT_GROUP_WAIT_TIME, 0, 0);
case BLKIO_PROP_idle_time:
return blkio_read_blkg_stats(blkcg, cft, cb,
- BLKIO_STAT_IDLE_TIME, 0);
+ BLKIO_STAT_IDLE_TIME, 0, 0);
case BLKIO_PROP_empty_time:
return blkio_read_blkg_stats(blkcg, cft, cb,
- BLKIO_STAT_EMPTY_TIME, 0);
+ BLKIO_STAT_EMPTY_TIME, 0, 0);
#endif
default:
BUG();
switch(name){
case BLKIO_THROTL_io_service_bytes:
return blkio_read_blkg_stats(blkcg, cft, cb,
- BLKIO_STAT_SERVICE_BYTES, 1);
+ BLKIO_STAT_CPU_SERVICE_BYTES, 1, 1);
case BLKIO_THROTL_io_serviced:
return blkio_read_blkg_stats(blkcg, cft, cb,
- BLKIO_STAT_SERVICED, 1);
+ BLKIO_STAT_CPU_SERVICED, 1, 1);
default:
BUG();
}
.read_map = blkiocg_file_read_map,
},
{
- .name = "unaccounted_time",
- .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP,
- BLKIO_PROP_unaccounted_time),
- .read_map = blkiocg_file_read_map,
- },
- {
.name = "io_service_bytes",
.private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP,
BLKIO_PROP_io_service_bytes),
BLKIO_PROP_dequeue),
.read_map = blkiocg_file_read_map,
},
+ {
+ .name = "unaccounted_time",
+ .private = BLKIOFILE_PRIVATE(BLKIO_POLICY_PROP,
+ BLKIO_PROP_unaccounted_time),
+ .read_map = blkiocg_file_read_map,
+ },
#endif
};
ARRAY_SIZE(blkio_files));
}
-static void blkiocg_destroy(struct cgroup_subsys *subsys, struct cgroup *cgroup)
+static void blkiocg_destroy(struct cgroup *cgroup)
{
struct blkio_cgroup *blkcg = cgroup_to_blkio_cgroup(cgroup);
unsigned long flags;
kfree(blkcg);
}
-static struct cgroup_subsys_state *
-blkiocg_create(struct cgroup_subsys *subsys, struct cgroup *cgroup)
+static struct cgroup_subsys_state *blkiocg_create(struct cgroup *cgroup)
{
struct blkio_cgroup *blkcg;
struct cgroup *parent = cgroup->parent;
* of the main cic data structures. For now we allow a task to change
* its cgroup only if it's the only owner of its ioc.
*/
-static int blkiocg_can_attach(struct cgroup_subsys *subsys,
- struct cgroup *cgroup, struct task_struct *tsk,
- bool threadgroup)
+static int blkiocg_can_attach(struct cgroup *cgrp, struct cgroup_taskset *tset)
{
+ struct task_struct *task;
struct io_context *ioc;
int ret = 0;
/* task_lock() is needed to avoid races with exit_io_context() */
- task_lock(tsk);
- ioc = tsk->io_context;
- if (ioc && atomic_read(&ioc->nr_tasks) > 1)
- ret = -EINVAL;
- task_unlock(tsk);
-
+ cgroup_taskset_for_each(task, cgrp, tset) {
+ task_lock(task);
+ ioc = task->io_context;
+ if (ioc && atomic_read(&ioc->nr_tasks) > 1)
+ ret = -EINVAL;
+ task_unlock(task);
+ if (ret)
+ break;
+ }
return ret;
}
-static void blkiocg_attach(struct cgroup_subsys *subsys, struct cgroup *cgroup,
- struct cgroup *prev, struct task_struct *tsk,
- bool threadgroup)
+static void blkiocg_attach(struct cgroup *cgrp, struct cgroup_taskset *tset)
{
+ struct task_struct *task;
struct io_context *ioc;
- task_lock(tsk);
- ioc = tsk->io_context;
- if (ioc)
- ioc->cgroup_changed = 1;
- task_unlock(tsk);
+ cgroup_taskset_for_each(task, cgrp, tset) {
+ /* we don't lose anything even if ioc allocation fails */
+ ioc = get_task_io_context(task, GFP_ATOMIC, NUMA_NO_NODE);
+ if (ioc) {
+ ioc_cgroup_changed(ioc);
+ put_io_context(ioc);
+ }
+ }
}
void blkio_policy_register(struct blkio_policy_type *blkiop)
projects / linux-flexiantxendom0-3.2.10.git / blobdiff