#include <linux/cgroup.h>
#include <linux/u64_stats_sync.h>
#include <linux/seq_file.h>
+#include <linux/radix-tree.h>
+#include <linux/blkdev.h>
/* Max limits for throttle policy */
#define THROTL_IOPS_MAX UINT_MAX
BLKG_RWSTAT_TOTAL = BLKG_RWSTAT_NR,
};
-struct blkio_cgroup {
+struct blkcg_gq;
+
+struct blkcg {
struct cgroup_subsys_state css;
spinlock_t lock;
+
+ struct radix_tree_root blkg_tree;
+ struct blkcg_gq *blkg_hint;
struct hlist_head blkg_list;
/* for policies to test whether associated blkcg has changed */
uint64_t id;
- /* TODO: per-policy storage in blkio_cgroup */
+ /* TODO: per-policy storage in blkcg */
unsigned int cfq_weight; /* belongs to cfq */
};
uint64_t cnt[BLKG_RWSTAT_NR];
};
-/* per-blkg per-policy data */
+/*
+ * A blkcg_gq (blkg) is association between a block cgroup (blkcg) and a
+ * request_queue (q). This is used by blkcg policies which need to track
+ * information per blkcg - q pair.
+ *
+ * There can be multiple active blkcg policies and each has its private
+ * data on each blkg, the size of which is determined by
+ * blkcg_policy->pd_size. blkcg core allocates and frees such areas
+ * together with blkg and invokes pd_init/exit_fn() methods.
+ *
+ * Such private data must embed struct blkg_policy_data (pd) at the
+ * beginning and pd_size can't be smaller than pd.
+ */
struct blkg_policy_data {
/* the blkg this per-policy data belongs to */
- struct blkio_group *blkg;
+ struct blkcg_gq *blkg;
/* used during policy activation */
struct list_head alloc_node;
-
- /* pol->pdata_size bytes of private data used by policy impl */
- char pdata[] __aligned(__alignof__(unsigned long long));
};
-struct blkio_group {
+/* association between a blk cgroup and a request queue */
+struct blkcg_gq {
/* Pointer to the associated request_queue */
struct request_queue *q;
struct list_head q_node;
struct hlist_node blkcg_node;
- struct blkio_cgroup *blkcg;
+ struct blkcg *blkcg;
+ /* request allocation list for this blkcg-q pair */
+ struct request_list rl;
/* reference count */
int refcnt;
struct rcu_head rcu_head;
};
-typedef void (blkio_init_group_fn)(struct blkio_group *blkg);
-typedef void (blkio_exit_group_fn)(struct blkio_group *blkg);
-typedef void (blkio_reset_group_stats_fn)(struct blkio_group *blkg);
+typedef void (blkcg_pol_init_pd_fn)(struct blkcg_gq *blkg);
+typedef void (blkcg_pol_exit_pd_fn)(struct blkcg_gq *blkg);
+typedef void (blkcg_pol_reset_pd_stats_fn)(struct blkcg_gq *blkg);
-struct blkio_policy_ops {
- blkio_init_group_fn *blkio_init_group_fn;
- blkio_exit_group_fn *blkio_exit_group_fn;
- blkio_reset_group_stats_fn *blkio_reset_group_stats_fn;
-};
-
-struct blkio_policy_type {
- struct blkio_policy_ops ops;
+struct blkcg_policy {
int plid;
/* policy specific private data size */
- size_t pdata_size;
+ size_t pd_size;
/* cgroup files for the policy */
struct cftype *cftypes;
+
+ /* operations */
+ blkcg_pol_init_pd_fn *pd_init_fn;
+ blkcg_pol_exit_pd_fn *pd_exit_fn;
+ blkcg_pol_reset_pd_stats_fn *pd_reset_stats_fn;
};
-extern struct blkio_cgroup blkio_root_cgroup;
+extern struct blkcg blkcg_root;
-struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup);
-struct blkio_cgroup *bio_blkio_cgroup(struct bio *bio);
-struct blkio_group *blkg_lookup(struct blkio_cgroup *blkcg,
- struct request_queue *q);
-struct blkio_group *blkg_lookup_create(struct blkio_cgroup *blkcg,
- struct request_queue *q);
+struct blkcg_gq *blkg_lookup(struct blkcg *blkcg, struct request_queue *q);
+struct blkcg_gq *blkg_lookup_create(struct blkcg *blkcg,
+ struct request_queue *q);
int blkcg_init_queue(struct request_queue *q);
void blkcg_drain_queue(struct request_queue *q);
void blkcg_exit_queue(struct request_queue *q);
/* Blkio controller policy registration */
-int blkio_policy_register(struct blkio_policy_type *);
-void blkio_policy_unregister(struct blkio_policy_type *);
+int blkcg_policy_register(struct blkcg_policy *pol);
+void blkcg_policy_unregister(struct blkcg_policy *pol);
int blkcg_activate_policy(struct request_queue *q,
- const struct blkio_policy_type *pol);
+ const struct blkcg_policy *pol);
void blkcg_deactivate_policy(struct request_queue *q,
- const struct blkio_policy_type *pol);
+ const struct blkcg_policy *pol);
-void blkcg_print_blkgs(struct seq_file *sf, struct blkio_cgroup *blkcg,
- u64 (*prfill)(struct seq_file *, void *, int),
- const struct blkio_policy_type *pol, int data,
+void blkcg_print_blkgs(struct seq_file *sf, struct blkcg *blkcg,
+ u64 (*prfill)(struct seq_file *,
+ struct blkg_policy_data *, int),
+ const struct blkcg_policy *pol, int data,
bool show_total);
-u64 __blkg_prfill_u64(struct seq_file *sf, void *pdata, u64 v);
-u64 __blkg_prfill_rwstat(struct seq_file *sf, void *pdata,
+u64 __blkg_prfill_u64(struct seq_file *sf, struct blkg_policy_data *pd, u64 v);
+u64 __blkg_prfill_rwstat(struct seq_file *sf, struct blkg_policy_data *pd,
const struct blkg_rwstat *rwstat);
-u64 blkg_prfill_stat(struct seq_file *sf, void *pdata, int off);
-u64 blkg_prfill_rwstat(struct seq_file *sf, void *pdata, int off);
+u64 blkg_prfill_stat(struct seq_file *sf, struct blkg_policy_data *pd, int off);
+u64 blkg_prfill_rwstat(struct seq_file *sf, struct blkg_policy_data *pd,
+ int off);
struct blkg_conf_ctx {
struct gendisk *disk;
- struct blkio_group *blkg;
+ struct blkcg_gq *blkg;
u64 v;
};
-int blkg_conf_prep(struct blkio_cgroup *blkcg,
- const struct blkio_policy_type *pol, const char *input,
- struct blkg_conf_ctx *ctx);
+int blkg_conf_prep(struct blkcg *blkcg, const struct blkcg_policy *pol,
+ const char *input, struct blkg_conf_ctx *ctx);
void blkg_conf_finish(struct blkg_conf_ctx *ctx);
+static inline struct blkcg *cgroup_to_blkcg(struct cgroup *cgroup)
+{
+ return container_of(cgroup_subsys_state(cgroup, blkio_subsys_id),
+ struct blkcg, css);
+}
+
+static inline struct blkcg *task_blkcg(struct task_struct *tsk)
+{
+ return container_of(task_subsys_state(tsk, blkio_subsys_id),
+ struct blkcg, css);
+}
+
+static inline struct blkcg *bio_blkcg(struct bio *bio)
+{
+ if (bio && bio->bi_css)
+ return container_of(bio->bi_css, struct blkcg, css);
+ return task_blkcg(current);
+}
+
/**
* blkg_to_pdata - get policy private data
* @blkg: blkg of interest
*
* Return pointer to private data associated with the @blkg-@pol pair.
*/
-static inline void *blkg_to_pdata(struct blkio_group *blkg,
- struct blkio_policy_type *pol)
+static inline struct blkg_policy_data *blkg_to_pd(struct blkcg_gq *blkg,
+ struct blkcg_policy *pol)
{
- return blkg ? blkg->pd[pol->plid]->pdata : NULL;
+ return blkg ? blkg->pd[pol->plid] : NULL;
}
/**
* pdata_to_blkg - get blkg associated with policy private data
- * @pdata: policy private data of interest
+ * @pd: policy private data of interest
*
- * @pdata is policy private data. Determine the blkg it's associated with.
+ * @pd is policy private data. Determine the blkg it's associated with.
*/
-static inline struct blkio_group *pdata_to_blkg(void *pdata)
+static inline struct blkcg_gq *pd_to_blkg(struct blkg_policy_data *pd)
{
- if (pdata) {
- struct blkg_policy_data *pd =
- container_of(pdata, struct blkg_policy_data, pdata);
- return pd->blkg;
- }
- return NULL;
+ return pd ? pd->blkg : NULL;
}
/**
*
* Format the path of the cgroup of @blkg into @buf.
*/
-static inline int blkg_path(struct blkio_group *blkg, char *buf, int buflen)
+static inline int blkg_path(struct blkcg_gq *blkg, char *buf, int buflen)
{
int ret;
*
* The caller should be holding queue_lock and an existing reference.
*/
-static inline void blkg_get(struct blkio_group *blkg)
+static inline void blkg_get(struct blkcg_gq *blkg)
{
lockdep_assert_held(blkg->q->queue_lock);
WARN_ON_ONCE(!blkg->refcnt);
blkg->refcnt++;
}
-void __blkg_release(struct blkio_group *blkg);
+void __blkg_release(struct blkcg_gq *blkg);
/**
* blkg_put - put a blkg reference
*
* The caller should be holding queue_lock.
*/
-static inline void blkg_put(struct blkio_group *blkg)
+static inline void blkg_put(struct blkcg_gq *blkg)
{
lockdep_assert_held(blkg->q->queue_lock);
WARN_ON_ONCE(blkg->refcnt <= 0);
__blkg_release(blkg);
}
+/**
+ * blk_get_rl - get request_list to use
+ * @q: request_queue of interest
+ * @bio: bio which will be attached to the allocated request (may be %NULL)
+ *
+ * The caller wants to allocate a request from @q to use for @bio. Find
+ * the request_list to use and obtain a reference on it. Should be called
+ * under queue_lock. This function is guaranteed to return non-%NULL
+ * request_list.
+ */
+static inline struct request_list *blk_get_rl(struct request_queue *q,
+ struct bio *bio)
+{
+ struct blkcg *blkcg;
+ struct blkcg_gq *blkg;
+
+ rcu_read_lock();
+
+ blkcg = bio_blkcg(bio);
+
+ /* bypass blkg lookup and use @q->root_rl directly for root */
+ if (blkcg == &blkcg_root)
+ goto root_rl;
+
+ /*
+ * Try to use blkg->rl. blkg lookup may fail under memory pressure
+ * or if either the blkcg or queue is going away. Fall back to
+ * root_rl in such cases.
+ */
+ blkg = blkg_lookup_create(blkcg, q);
+ if (unlikely(IS_ERR(blkg)))
+ goto root_rl;
+
+ blkg_get(blkg);
+ rcu_read_unlock();
+ return &blkg->rl;
+root_rl:
+ rcu_read_unlock();
+ return &q->root_rl;
+}
+
+/**
+ * blk_put_rl - put request_list
+ * @rl: request_list to put
+ *
+ * Put the reference acquired by blk_get_rl(). Should be called under
+ * queue_lock.
+ */
+static inline void blk_put_rl(struct request_list *rl)
+{
+ /* root_rl may not have blkg set */
+ if (rl->blkg && rl->blkg->blkcg != &blkcg_root)
+ blkg_put(rl->blkg);
+}
+
+/**
+ * blk_rq_set_rl - associate a request with a request_list
+ * @rq: request of interest
+ * @rl: target request_list
+ *
+ * Associate @rq with @rl so that accounting and freeing can know the
+ * request_list @rq came from.
+ */
+static inline void blk_rq_set_rl(struct request *rq, struct request_list *rl)
+{
+ rq->rl = rl;
+}
+
+/**
+ * blk_rq_rl - return the request_list a request came from
+ * @rq: request of interest
+ *
+ * Return the request_list @rq is allocated from.
+ */
+static inline struct request_list *blk_rq_rl(struct request *rq)
+{
+ return rq->rl;
+}
+
+struct request_list *__blk_queue_next_rl(struct request_list *rl,
+ struct request_queue *q);
+/**
+ * blk_queue_for_each_rl - iterate through all request_lists of a request_queue
+ *
+ * Should be used under queue_lock.
+ */
+#define blk_queue_for_each_rl(rl, q) \
+ for ((rl) = &(q)->root_rl; (rl); (rl) = __blk_queue_next_rl((rl), (q)))
+
/**
* blkg_stat_add - add a value to a blkg_stat
* @stat: target blkg_stat
#else /* CONFIG_BLK_CGROUP */
struct cgroup;
+struct blkcg;
+
+struct blkg_policy_data {
+};
-struct blkio_group {
+struct blkcg_gq {
};
-struct blkio_policy_type {
+struct blkcg_policy {
};
-static inline struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup) { return NULL; }
-static inline struct blkio_cgroup *bio_blkio_cgroup(struct bio *bio) { return NULL; }
-static inline struct blkio_group *blkg_lookup(struct blkio_cgroup *blkcg, void *key) { return NULL; }
+static inline struct blkcg_gq *blkg_lookup(struct blkcg *blkcg, void *key) { return NULL; }
static inline int blkcg_init_queue(struct request_queue *q) { return 0; }
static inline void blkcg_drain_queue(struct request_queue *q) { }
static inline void blkcg_exit_queue(struct request_queue *q) { }
-static inline int blkio_policy_register(struct blkio_policy_type *blkiop) { return 0; }
-static inline void blkio_policy_unregister(struct blkio_policy_type *blkiop) { }
+static inline int blkcg_policy_register(struct blkcg_policy *pol) { return 0; }
+static inline void blkcg_policy_unregister(struct blkcg_policy *pol) { }
static inline int blkcg_activate_policy(struct request_queue *q,
- const struct blkio_policy_type *pol) { return 0; }
+ const struct blkcg_policy *pol) { return 0; }
static inline void blkcg_deactivate_policy(struct request_queue *q,
- const struct blkio_policy_type *pol) { }
-
-static inline void *blkg_to_pdata(struct blkio_group *blkg,
- struct blkio_policy_type *pol) { return NULL; }
-static inline struct blkio_group *pdata_to_blkg(void *pdata,
- struct blkio_policy_type *pol) { return NULL; }
-static inline char *blkg_path(struct blkio_group *blkg) { return NULL; }
-static inline void blkg_get(struct blkio_group *blkg) { }
-static inline void blkg_put(struct blkio_group *blkg) { }
+ const struct blkcg_policy *pol) { }
+
+static inline struct blkcg *cgroup_to_blkcg(struct cgroup *cgroup) { return NULL; }
+static inline struct blkcg *bio_blkcg(struct bio *bio) { return NULL; }
+
+static inline struct blkg_policy_data *blkg_to_pd(struct blkcg_gq *blkg,
+ struct blkcg_policy *pol) { return NULL; }
+static inline struct blkcg_gq *pd_to_blkg(struct blkg_policy_data *pd) { return NULL; }
+static inline char *blkg_path(struct blkcg_gq *blkg) { return NULL; }
+static inline void blkg_get(struct blkcg_gq *blkg) { }
+static inline void blkg_put(struct blkcg_gq *blkg) { }
+
+static inline struct request_list *blk_get_rl(struct request_queue *q,
+ struct bio *bio) { return &q->root_rl; }
+static inline void blk_put_rl(struct request_list *rl) { }
+static inline void blk_rq_set_rl(struct request *rq, struct request_list *rl) { }
+static inline struct request_list *blk_rq_rl(struct request *rq) { return &rq->q->root_rl; }
+
+#define blk_queue_for_each_rl(rl, q) \
+ for ((rl) = &(q)->root_rl; (rl); (rl) = NULL)
#endif /* CONFIG_BLK_CGROUP */
#endif /* _BLK_CGROUP_H */
projects / karo-tx-linux.git / blobdiff