Merge branch 'for-3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull cgroup updates from Tejun Heo:
 "The bulk of changes are cleanups and preparations for the upcoming
  kernfs conversion.

   - cgroup_event mechanism which is and will be used only by memcg is
     moved to memcg.

   - pidlist handling is updated so that it can be served by seq_file.

     Also, the list is not sorted if sane_behavior.  cgroup
     documentation explicitly states that the file is not sorted but it
     has been for quite some time.

   - All cgroup file handling now happens on top of seq_file.  This is
     to prepare for kernfs conversion.  In addition, all operations are
     restructured so that they map 1-1 to kernfs operations.

   - Other cleanups and low-pri fixes"

* 'for-3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (40 commits)
  cgroup: trivial style updates
  cgroup: remove stray references to css_id
  doc: cgroups: Fix typo in doc/cgroups
  cgroup: fix fail path in cgroup_load_subsys()
  cgroup: fix missing unlock on error in cgroup_load_subsys()
  cgroup: remove for_each_root_subsys()
  cgroup: implement for_each_css()
  cgroup: factor out cgroup_subsys_state creation into create_css()
  cgroup: combine css handling loops in cgroup_create()
  cgroup: reorder operations in cgroup_create()
  cgroup: make for_each_subsys() useable under cgroup_root_mutex
  cgroup: css iterations and css_from_dir() are safe under cgroup_mutex
  cgroup: unify pidlist and other file handling
  cgroup: replace cftype->read_seq_string() with cftype->seq_show()
  cgroup: attach cgroup_open_file to all cgroup files
  cgroup: generalize cgroup_pidlist_open_file
  cgroup: unify read path so that seq_file is always used
  cgroup: unify cgroup_write_X64() and cgroup_write_string()
  cgroup: remove cftype->read(), ->read_map() and ->write()
  hugetlb_cgroup: convert away from cftype->read()
  ...

2 files changed, 73 insertions, 93 deletions

diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 06534049afba..a760857e6b62 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -1303,13 +1303,10 @@ static u64 tg_prfill_cpu_rwstat(struct seq_file *sf,
         return __blkg_prfill_rwstat(sf, pd, &rwstat);
 }
 
-static int tg_print_cpu_rwstat(struct cgroup_subsys_state *css,
-                               struct cftype *cft, struct seq_file *sf)
+static int tg_print_cpu_rwstat(struct seq_file *sf, void *v)
 {
-        struct blkcg *blkcg = css_to_blkcg(css);
-
-        blkcg_print_blkgs(sf, blkcg, tg_prfill_cpu_rwstat, &blkcg_policy_throtl,
-                          cft->private, true);
+        blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_cpu_rwstat,
+                          &blkcg_policy_throtl, seq_cft(sf)->private, true);
         return 0;
 }
 
@@ -1335,19 +1332,17 @@ static u64 tg_prfill_conf_uint(struct seq_file *sf, struct blkg_policy_data *pd,
         return __blkg_prfill_u64(sf, pd, v);
 }
 
-static int tg_print_conf_u64(struct cgroup_subsys_state *css,
-                             struct cftype *cft, struct seq_file *sf)
+static int tg_print_conf_u64(struct seq_file *sf, void *v)
 {
-        blkcg_print_blkgs(sf, css_to_blkcg(css), tg_prfill_conf_u64,
-                          &blkcg_policy_throtl, cft->private, false);
+        blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_conf_u64,
+                          &blkcg_policy_throtl, seq_cft(sf)->private, false);
         return 0;
 }
 
-static int tg_print_conf_uint(struct cgroup_subsys_state *css,
-                              struct cftype *cft, struct seq_file *sf)
+static int tg_print_conf_uint(struct seq_file *sf, void *v)
 {
-        blkcg_print_blkgs(sf, css_to_blkcg(css), tg_prfill_conf_uint,
-                          &blkcg_policy_throtl, cft->private, false);
+        blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_conf_uint,
+                          &blkcg_policy_throtl, seq_cft(sf)->private, false);
         return 0;
 }
 
@@ -1428,40 +1423,40 @@ static struct cftype throtl_files[] = {
         {
                 .name = "throttle.read_bps_device",
                 .private = offsetof(struct throtl_grp, bps[READ]),
-                .read_seq_string = tg_print_conf_u64,
+                .seq_show = tg_print_conf_u64,
                 .write_string = tg_set_conf_u64,
                 .max_write_len = 256,
         },
         {
                 .name = "throttle.write_bps_device",
                 .private = offsetof(struct throtl_grp, bps[WRITE]),
-                .read_seq_string = tg_print_conf_u64,
+                .seq_show = tg_print_conf_u64,
                 .write_string = tg_set_conf_u64,
                 .max_write_len = 256,
         },
         {
                 .name = "throttle.read_iops_device",
                 .private = offsetof(struct throtl_grp, iops[READ]),
-                .read_seq_string = tg_print_conf_uint,
+                .seq_show = tg_print_conf_uint,
                 .write_string = tg_set_conf_uint,
                 .max_write_len = 256,
         },
         {
                 .name = "throttle.write_iops_device",
                 .private = offsetof(struct throtl_grp, iops[WRITE]),
-                .read_seq_string = tg_print_conf_uint,
+                .seq_show = tg_print_conf_uint,
                 .write_string = tg_set_conf_uint,
                 .max_write_len = 256,
         },
         {
                 .name = "throttle.io_service_bytes",
                 .private = offsetof(struct tg_stats_cpu, service_bytes),
-                .read_seq_string = tg_print_cpu_rwstat,
+                .seq_show = tg_print_cpu_rwstat,
         },
         {
                 .name = "throttle.io_serviced",
                 .private = offsetof(struct tg_stats_cpu, serviced),
-                .read_seq_string = tg_print_cpu_rwstat,
+                .seq_show = tg_print_cpu_rwstat,
         },
         { }     /* terminate */
 };
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 4d5cec1ad80d..744833b630c6 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -1632,11 +1632,11 @@ static u64 cfqg_prfill_weight_device(struct seq_file *sf,
         return __blkg_prfill_u64(sf, pd, cfqg->dev_weight);
 }
 
-static int cfqg_print_weight_device(struct cgroup_subsys_state *css,
-                                    struct cftype *cft, struct seq_file *sf)
+static int cfqg_print_weight_device(struct seq_file *sf, void *v)
 {
-        blkcg_print_blkgs(sf, css_to_blkcg(css), cfqg_prfill_weight_device,
-                          &blkcg_policy_cfq, 0, false);
+        blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)),
+                          cfqg_prfill_weight_device, &blkcg_policy_cfq,
+                          0, false);
         return 0;
 }
 
@@ -1650,26 +1650,23 @@ static u64 cfqg_prfill_leaf_weight_device(struct seq_file *sf,
         return __blkg_prfill_u64(sf, pd, cfqg->dev_leaf_weight);
 }
 
-static int cfqg_print_leaf_weight_device(struct cgroup_subsys_state *css,
-                                         struct cftype *cft,
-                                         struct seq_file *sf)
+static int cfqg_print_leaf_weight_device(struct seq_file *sf, void *v)
 {
-        blkcg_print_blkgs(sf, css_to_blkcg(css), cfqg_prfill_leaf_weight_device,
-                          &blkcg_policy_cfq, 0, false);
+        blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)),
+                          cfqg_prfill_leaf_weight_device, &blkcg_policy_cfq,
+                          0, false);
         return 0;
 }
 
-static int cfq_print_weight(struct cgroup_subsys_state *css, struct cftype *cft,
-                            struct seq_file *sf)
+static int cfq_print_weight(struct seq_file *sf, void *v)
 {
-        seq_printf(sf, "%u\n", css_to_blkcg(css)->cfq_weight);
+        seq_printf(sf, "%u\n", css_to_blkcg(seq_css(sf))->cfq_weight);
         return 0;
 }
 
-static int cfq_print_leaf_weight(struct cgroup_subsys_state *css,
-                                 struct cftype *cft, struct seq_file *sf)
+static int cfq_print_leaf_weight(struct seq_file *sf, void *v)
 {
-        seq_printf(sf, "%u\n", css_to_blkcg(css)->cfq_leaf_weight);
+        seq_printf(sf, "%u\n", css_to_blkcg(seq_css(sf))->cfq_leaf_weight);
         return 0;
 }
 
@@ -1762,23 +1759,17 @@ static int cfq_set_leaf_weight(struct cgroup_subsys_state *css,
         return __cfq_set_weight(css, cft, val, true);
 }
 
-static int cfqg_print_stat(struct cgroup_subsys_state *css, struct cftype *cft,
-                           struct seq_file *sf)
+static int cfqg_print_stat(struct seq_file *sf, void *v)
 {
-        struct blkcg *blkcg = css_to_blkcg(css);
-
-        blkcg_print_blkgs(sf, blkcg, blkg_prfill_stat, &blkcg_policy_cfq,
-                          cft->private, false);
+        blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), blkg_prfill_stat,
+                          &blkcg_policy_cfq, seq_cft(sf)->private, false);
         return 0;
 }
 
-static int cfqg_print_rwstat(struct cgroup_subsys_state *css,
-                             struct cftype *cft, struct seq_file *sf)
+static int cfqg_print_rwstat(struct seq_file *sf, void *v)
 {
-        struct blkcg *blkcg = css_to_blkcg(css);
-
-        blkcg_print_blkgs(sf, blkcg, blkg_prfill_rwstat, &blkcg_policy_cfq,
-                          cft->private, true);
+        blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), blkg_prfill_rwstat,
+                          &blkcg_policy_cfq, seq_cft(sf)->private, true);
         return 0;
 }
 
@@ -1798,23 +1789,19 @@ static u64 cfqg_prfill_rwstat_recursive(struct seq_file *sf,
         return __blkg_prfill_rwstat(sf, pd, &sum);
 }
 
-static int cfqg_print_stat_recursive(struct cgroup_subsys_state *css,
-                                     struct cftype *cft, struct seq_file *sf)
+static int cfqg_print_stat_recursive(struct seq_file *sf, void *v)
 {
-        struct blkcg *blkcg = css_to_blkcg(css);
-
-        blkcg_print_blkgs(sf, blkcg, cfqg_prfill_stat_recursive,
-                          &blkcg_policy_cfq, cft->private, false);
+        blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)),
+                          cfqg_prfill_stat_recursive, &blkcg_policy_cfq,
+                          seq_cft(sf)->private, false);
         return 0;
 }
 
-static int cfqg_print_rwstat_recursive(struct cgroup_subsys_state *css,
-                                       struct cftype *cft, struct seq_file *sf)
+static int cfqg_print_rwstat_recursive(struct seq_file *sf, void *v)
 {
-        struct blkcg *blkcg = css_to_blkcg(css);
-
-        blkcg_print_blkgs(sf, blkcg, cfqg_prfill_rwstat_recursive,
-                          &blkcg_policy_cfq, cft->private, true);
+        blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)),
+                          cfqg_prfill_rwstat_recursive, &blkcg_policy_cfq,
+                          seq_cft(sf)->private, true);
         return 0;
 }
 
@@ -1835,13 +1822,11 @@ static u64 cfqg_prfill_avg_queue_size(struct seq_file *sf,
 }
 
 /* print avg_queue_size */
-static int cfqg_print_avg_queue_size(struct cgroup_subsys_state *css,
-                                     struct cftype *cft, struct seq_file *sf)
+static int cfqg_print_avg_queue_size(struct seq_file *sf, void *v)
 {
-        struct blkcg *blkcg = css_to_blkcg(css);
-
-        blkcg_print_blkgs(sf, blkcg, cfqg_prfill_avg_queue_size,
-                          &blkcg_policy_cfq, 0, false);
+        blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)),
+                          cfqg_prfill_avg_queue_size, &blkcg_policy_cfq,
+                          0, false);
         return 0;
 }
 #endif  /* CONFIG_DEBUG_BLK_CGROUP */
@@ -1851,14 +1836,14 @@ static struct cftype cfq_blkcg_files[] = {
         {
                 .name = "weight_device",
                 .flags = CFTYPE_ONLY_ON_ROOT,
-                .read_seq_string = cfqg_print_leaf_weight_device,
+                .seq_show = cfqg_print_leaf_weight_device,
                 .write_string = cfqg_set_leaf_weight_device,
                 .max_write_len = 256,
         },
         {
                 .name = "weight",
                 .flags = CFTYPE_ONLY_ON_ROOT,
-                .read_seq_string = cfq_print_leaf_weight,
+                .seq_show = cfq_print_leaf_weight,
                 .write_u64 = cfq_set_leaf_weight,
         },
 
@@ -1866,26 +1851,26 @@ static struct cftype cfq_blkcg_files[] = {
         {
                 .name = "weight_device",
                 .flags = CFTYPE_NOT_ON_ROOT,
-                .read_seq_string = cfqg_print_weight_device,
+                .seq_show = cfqg_print_weight_device,
                 .write_string = cfqg_set_weight_device,
                 .max_write_len = 256,
         },
         {
                 .name = "weight",
                 .flags = CFTYPE_NOT_ON_ROOT,
-                .read_seq_string = cfq_print_weight,
+                .seq_show = cfq_print_weight,
                 .write_u64 = cfq_set_weight,
         },
 
         {
                 .name = "leaf_weight_device",
-                .read_seq_string = cfqg_print_leaf_weight_device,
+                .seq_show = cfqg_print_leaf_weight_device,
                 .write_string = cfqg_set_leaf_weight_device,
                 .max_write_len = 256,
         },
         {
                 .name = "leaf_weight",
-                .read_seq_string = cfq_print_leaf_weight,
+                .seq_show = cfq_print_leaf_weight,
                 .write_u64 = cfq_set_leaf_weight,
         },
 
@@ -1893,114 +1878,114 @@ static struct cftype cfq_blkcg_files[] = {
         {
                 .name = "time",
                 .private = offsetof(struct cfq_group, stats.time),
-                .read_seq_string = cfqg_print_stat,
+                .seq_show = cfqg_print_stat,
         },
         {
                 .name = "sectors",
                 .private = offsetof(struct cfq_group, stats.sectors),
-                .read_seq_string = cfqg_print_stat,
+                .seq_show = cfqg_print_stat,
         },
         {
                 .name = "io_service_bytes",
                 .private = offsetof(struct cfq_group, stats.service_bytes),
-                .read_seq_string = cfqg_print_rwstat,
+                .seq_show = cfqg_print_rwstat,
         },
         {
                 .name = "io_serviced",
                 .private = offsetof(struct cfq_group, stats.serviced),
-                .read_seq_string = cfqg_print_rwstat,
+                .seq_show = cfqg_print_rwstat,
         },
         {
                 .name = "io_service_time",
                 .private = offsetof(struct cfq_group, stats.service_time),
-                .read_seq_string = cfqg_print_rwstat,
+                .seq_show = cfqg_print_rwstat,
         },
         {
                 .name = "io_wait_time",
                 .private = offsetof(struct cfq_group, stats.wait_time),
-                .read_seq_string = cfqg_print_rwstat,
+                .seq_show = cfqg_print_rwstat,
         },
         {
                 .name = "io_merged",
                 .private = offsetof(struct cfq_group, stats.merged),
-                .read_seq_string = cfqg_print_rwstat,
+                .seq_show = cfqg_print_rwstat,
         },
         {
                 .name = "io_queued",
                 .private = offsetof(struct cfq_group, stats.queued),
-                .read_seq_string = cfqg_print_rwstat,
+                .seq_show = cfqg_print_rwstat,
         },
 
         /* the same statictics which cover the cfqg and its descendants */
         {
                 .name = "time_recursive",
                 .private = offsetof(struct cfq_group, stats.time),
-                .read_seq_string = cfqg_print_stat_recursive,
+                .seq_show = cfqg_print_stat_recursive,
         },
         {
                 .name = "sectors_recursive",
                 .private = offsetof(struct cfq_group, stats.sectors),
-                .read_seq_string = cfqg_print_stat_recursive,
+                .seq_show = cfqg_print_stat_recursive,
         },
         {
                 .name = "io_service_bytes_recursive",
                 .private = offsetof(struct cfq_group, stats.service_bytes),
-                .read_seq_string = cfqg_print_rwstat_recursive,
+                .seq_show = cfqg_print_rwstat_recursive,
         },
         {
                 .name = "io_serviced_recursive",
                 .private = offsetof(struct cfq_group, stats.serviced),
-                .read_seq_string = cfqg_print_rwstat_recursive,
+                .seq_show = cfqg_print_rwstat_recursive,
         },
         {
                 .name = "io_service_time_recursive",
                 .private = offsetof(struct cfq_group, stats.service_time),
-                .read_seq_string = cfqg_print_rwstat_recursive,
+                .seq_show = cfqg_print_rwstat_recursive,
         },
         {
                 .name = "io_wait_time_recursive",
                 .private = offsetof(struct cfq_group, stats.wait_time),
-                .read_seq_string = cfqg_print_rwstat_recursive,
+                .seq_show = cfqg_print_rwstat_recursive,
         },
         {
                 .name = "io_merged_recursive",
                 .private = offsetof(struct cfq_group, stats.merged),
-                .read_seq_string = cfqg_print_rwstat_recursive,
+                .seq_show = cfqg_print_rwstat_recursive,
         },
         {
                 .name = "io_queued_recursive",
                 .private = offsetof(struct cfq_group, stats.queued),
-                .read_seq_string = cfqg_print_rwstat_recursive,
+                .seq_show = cfqg_print_rwstat_recursive,
         },
 #ifdef CONFIG_DEBUG_BLK_CGROUP
         {
                 .name = "avg_queue_size",
-                .read_seq_string = cfqg_print_avg_queue_size,
+                .seq_show = cfqg_print_avg_queue_size,
         },
         {
                 .name = "group_wait_time",
                 .private = offsetof(struct cfq_group, stats.group_wait_time),
-                .read_seq_string = cfqg_print_stat,
+                .seq_show = cfqg_print_stat,
         },
         {
                 .name = "idle_time",
                 .private = offsetof(struct cfq_group, stats.idle_time),
-                .read_seq_string = cfqg_print_stat,
+                .seq_show = cfqg_print_stat,
         },
         {
                 .name = "empty_time",
                 .private = offsetof(struct cfq_group, stats.empty_time),
-                .read_seq_string = cfqg_print_stat,
+                .seq_show = cfqg_print_stat,
         },
         {
                 .name = "dequeue",
                 .private = offsetof(struct cfq_group, stats.dequeue),
-                .read_seq_string = cfqg_print_stat,
+                .seq_show = cfqg_print_stat,
         },
         {
                 .name = "unaccounted_time",
                 .private = offsetof(struct cfq_group, stats.unaccounted_time),
-                .read_seq_string = cfqg_print_stat,
+                .seq_show = cfqg_print_stat,
         },
 #endif  /* CONFIG_DEBUG_BLK_CGROUP */
         { }     /* terminate */