mm/hugetlb_cgroup: switch to the new cftypes

The previous patch has already reconstructed the cftype attributes based
on the templates and saved them in dfl_cftypes and legacy_cftypes.  then
remove the old procedure and switch to the new cftypes.

Link: https://lkml.kernel.org/r/20240612092409.2027592-4-xiujianfeng@huawei.comSigned-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

include/linux/hugetlb.h

@@ -686,11 +686,6 @@ struct hstate {
 	unsigned int nr_huge_pages_node[MAX_NUMNODES];
 	unsigned int free_huge_pages_node[MAX_NUMNODES];
 	unsigned int surplus_huge_pages_node[MAX_NUMNODES];
-#ifdef CONFIG_CGROUP_HUGETLB
-	/* cgroup control files */
-	struct cftype cgroup_files_dfl[8];
-	struct cftype cgroup_files_legacy[10];
-#endif
 	char name[HSTATE_NAME_LEN];
 };
 

mm/hugetlb_cgroup.c

@@ -841,164 +841,26 @@ hugetlb_cgroup_cfttypes_init(struct hstate *h, struct cftype *cft,
 	}
 }
 
-static void __init __hugetlb_cgroup_file_dfl_init(int idx)
+static void __init __hugetlb_cgroup_file_dfl_init(struct hstate *h)
 {
-	char buf[32];
-	struct cftype *cft;
-	struct hstate *h = &hstates[idx];
+	int idx = hstate_index(h);
 
 	hugetlb_cgroup_cfttypes_init(h, dfl_files + idx * DFL_TMPL_SIZE,
 				     hugetlb_dfl_tmpl, DFL_TMPL_SIZE);
-
-	/* format the size */
-	mem_fmt(buf, sizeof(buf), huge_page_size(h));
-
-	/* Add the limit file */
-	cft = &h->cgroup_files_dfl[0];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.max", buf);
-	cft->private = MEMFILE_PRIVATE(idx, RES_LIMIT);
-	cft->seq_show = hugetlb_cgroup_read_u64_max;
-	cft->write = hugetlb_cgroup_write_dfl;
-	cft->flags = CFTYPE_NOT_ON_ROOT;
-
-	/* Add the reservation limit file */
-	cft = &h->cgroup_files_dfl[1];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.rsvd.max", buf);
-	cft->private = MEMFILE_PRIVATE(idx, RES_RSVD_LIMIT);
-	cft->seq_show = hugetlb_cgroup_read_u64_max;
-	cft->write = hugetlb_cgroup_write_dfl;
-	cft->flags = CFTYPE_NOT_ON_ROOT;
-
-	/* Add the current usage file */
-	cft = &h->cgroup_files_dfl[2];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.current", buf);
-	cft->private = MEMFILE_PRIVATE(idx, RES_USAGE);
-	cft->seq_show = hugetlb_cgroup_read_u64_max;
-	cft->flags = CFTYPE_NOT_ON_ROOT;
-
-	/* Add the current reservation usage file */
-	cft = &h->cgroup_files_dfl[3];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.rsvd.current", buf);
-	cft->private = MEMFILE_PRIVATE(idx, RES_RSVD_USAGE);
-	cft->seq_show = hugetlb_cgroup_read_u64_max;
-	cft->flags = CFTYPE_NOT_ON_ROOT;
-
-	/* Add the events file */
-	cft = &h->cgroup_files_dfl[4];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.events", buf);
-	cft->private = MEMFILE_PRIVATE(idx, 0);
-	cft->seq_show = hugetlb_events_show;
-	cft->file_offset = offsetof(struct hugetlb_cgroup, events_file[idx]);
-	cft->flags = CFTYPE_NOT_ON_ROOT;
-
-	/* Add the events.local file */
-	cft = &h->cgroup_files_dfl[5];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.events.local", buf);
-	cft->private = MEMFILE_PRIVATE(idx, 0);
-	cft->seq_show = hugetlb_events_local_show;
-	cft->file_offset = offsetof(struct hugetlb_cgroup,
-				    events_local_file[idx]);
-	cft->flags = CFTYPE_NOT_ON_ROOT;
-
-	/* Add the numa stat file */
-	cft = &h->cgroup_files_dfl[6];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.numa_stat", buf);
-	cft->private = MEMFILE_PRIVATE(idx, 0);
-	cft->seq_show = hugetlb_cgroup_read_numa_stat;
-	cft->flags = CFTYPE_NOT_ON_ROOT;
-
-	/* NULL terminate the last cft */
-	cft = &h->cgroup_files_dfl[7];
-	memset(cft, 0, sizeof(*cft));
-
-	WARN_ON(cgroup_add_dfl_cftypes(&hugetlb_cgrp_subsys,
-				       h->cgroup_files_dfl));
 }
 
-static void __init __hugetlb_cgroup_file_legacy_init(int idx)
+static void __init __hugetlb_cgroup_file_legacy_init(struct hstate *h)
 {
-	char buf[32];
-	struct cftype *cft;
-	struct hstate *h = &hstates[idx];
+	int idx = hstate_index(h);
 
 	hugetlb_cgroup_cfttypes_init(h, legacy_files + idx * LEGACY_TMPL_SIZE,
 				     hugetlb_legacy_tmpl, LEGACY_TMPL_SIZE);
-
-	/* format the size */
-	mem_fmt(buf, sizeof(buf), huge_page_size(h));
-
-	/* Add the limit file */
-	cft = &h->cgroup_files_legacy[0];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.limit_in_bytes", buf);
-	cft->private = MEMFILE_PRIVATE(idx, RES_LIMIT);
-	cft->read_u64 = hugetlb_cgroup_read_u64;
-	cft->write = hugetlb_cgroup_write_legacy;
-
-	/* Add the reservation limit file */
-	cft = &h->cgroup_files_legacy[1];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.rsvd.limit_in_bytes", buf);
-	cft->private = MEMFILE_PRIVATE(idx, RES_RSVD_LIMIT);
-	cft->read_u64 = hugetlb_cgroup_read_u64;
-	cft->write = hugetlb_cgroup_write_legacy;
-
-	/* Add the usage file */
-	cft = &h->cgroup_files_legacy[2];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.usage_in_bytes", buf);
-	cft->private = MEMFILE_PRIVATE(idx, RES_USAGE);
-	cft->read_u64 = hugetlb_cgroup_read_u64;
-
-	/* Add the reservation usage file */
-	cft = &h->cgroup_files_legacy[3];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.rsvd.usage_in_bytes", buf);
-	cft->private = MEMFILE_PRIVATE(idx, RES_RSVD_USAGE);
-	cft->read_u64 = hugetlb_cgroup_read_u64;
-
-	/* Add the MAX usage file */
-	cft = &h->cgroup_files_legacy[4];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.max_usage_in_bytes", buf);
-	cft->private = MEMFILE_PRIVATE(idx, RES_MAX_USAGE);
-	cft->write = hugetlb_cgroup_reset;
-	cft->read_u64 = hugetlb_cgroup_read_u64;
-
-	/* Add the MAX reservation usage file */
-	cft = &h->cgroup_files_legacy[5];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.rsvd.max_usage_in_bytes", buf);
-	cft->private = MEMFILE_PRIVATE(idx, RES_RSVD_MAX_USAGE);
-	cft->write = hugetlb_cgroup_reset;
-	cft->read_u64 = hugetlb_cgroup_read_u64;
-
-	/* Add the failcntfile */
-	cft = &h->cgroup_files_legacy[6];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.failcnt", buf);
-	cft->private = MEMFILE_PRIVATE(idx, RES_FAILCNT);
-	cft->write = hugetlb_cgroup_reset;
-	cft->read_u64 = hugetlb_cgroup_read_u64;
-
-	/* Add the reservation failcntfile */
-	cft = &h->cgroup_files_legacy[7];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.rsvd.failcnt", buf);
-	cft->private = MEMFILE_PRIVATE(idx, RES_RSVD_FAILCNT);
-	cft->write = hugetlb_cgroup_reset;
-	cft->read_u64 = hugetlb_cgroup_read_u64;
-
-	/* Add the numa stat file */
-	cft = &h->cgroup_files_legacy[8];
-	snprintf(cft->name, MAX_CFTYPE_NAME, "%s.numa_stat", buf);
-	cft->private = MEMFILE_PRIVATE(idx, 0);
-	cft->seq_show = hugetlb_cgroup_read_numa_stat;
-
-	/* NULL terminate the last cft */
-	cft = &h->cgroup_files_legacy[9];
-	memset(cft, 0, sizeof(*cft));
-
-	WARN_ON(cgroup_add_legacy_cftypes(&hugetlb_cgrp_subsys,
-					  h->cgroup_files_legacy));
 }
 
-static void __init __hugetlb_cgroup_file_init(int idx)
+static void __init __hugetlb_cgroup_file_init(struct hstate *h)
 {
-	__hugetlb_cgroup_file_dfl_init(idx);
-	__hugetlb_cgroup_file_legacy_init(idx);
+	__hugetlb_cgroup_file_dfl_init(h);
+	__hugetlb_cgroup_file_legacy_init(h);
 }
 
 static void __init __hugetlb_cgroup_file_pre_init(void)
@@ -1013,13 +875,22 @@ static void __init __hugetlb_cgroup_file_pre_init(void)
 	BUG_ON(!legacy_files);
 }
 
+static void __init __hugetlb_cgroup_file_post_init(void)
+{
+	WARN_ON(cgroup_add_dfl_cftypes(&hugetlb_cgrp_subsys,
+				       dfl_files));
+	WARN_ON(cgroup_add_legacy_cftypes(&hugetlb_cgrp_subsys,
+					  legacy_files));
+}
+
 void __init hugetlb_cgroup_file_init(void)
 {
 	struct hstate *h;
 
 	__hugetlb_cgroup_file_pre_init();
 	for_each_hstate(h)
-		__hugetlb_cgroup_file_init(hstate_index(h));
+		__hugetlb_cgroup_file_init(h);
+	__hugetlb_cgroup_file_post_init();
 }
 
 /*