+ mm-hugetlb_cgroup-identify-the-legacy-using-cgroup_subsys_on_dfl.patch added to mm-unstable branch

+ mm-hugetlb_cgroup-identify-the-legacy-using-cgroup_subsys_on_dfl.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/hugetlb_cgroup: identify the legacy using cgroup_subsys_on_dfl()
has been added to the -mm mm-unstable branch.  Its filename is
     mm-hugetlb_cgroup-identify-the-legacy-using-cgroup_subsys_on_dfl.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-hugetlb_cgroup-identify-the-legacy-using-cgroup_subsys_on_dfl.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Xiu Jianfeng <xiujianfeng@huawei.com>
Subject: mm/hugetlb_cgroup: identify the legacy using cgroup_subsys_on_dfl()
Date: Wed, 12 Jun 2024 09:24:07 +0000

Patch series "mm/hugetlb_cgroup: rework on cftypes", v3.

This patchset provides an intuitive view of the control files through
static templates of cftypes.  This improves the readability of the code.  


This patch (of 3):

Currently the numa_stat file encodes 1 into .private using the micro
MEMFILE_PRIVATE() to identify the legacy.  Actually, we can use
cgroup_subsys_on_dfl() instead.  This is helpful to handle .private in the
static templates in the next patch.

Link: https://lkml.kernel.org/r/20240612092409.2027592-1-xiujianfeng@huawei.com
Link: https://lkml.kernel.org/r/20240612092409.2027592-2-xiujianfeng@huawei.com
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/hugetlb_cgroup.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/mm/hugetlb_cgroup.c~mm-hugetlb_cgroup-identify-the-legacy-using-cgroup_subsys_on_dfl
+++ a/mm/hugetlb_cgroup.c
@@ -460,7 +460,7 @@ static int hugetlb_cgroup_read_numa_stat
 	int nid;
 	struct cftype *cft = seq_cft(seq);
 	int idx = MEMFILE_IDX(cft->private);
-	bool legacy = MEMFILE_ATTR(cft->private);
+	bool legacy = !cgroup_subsys_on_dfl(hugetlb_cgrp_subsys);
 	struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(seq_css(seq));
 	struct cgroup_subsys_state *css;
 	unsigned long usage;
@@ -839,7 +839,7 @@ static void __init __hugetlb_cgroup_file
 	/* 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, 1);
+	cft->private = MEMFILE_PRIVATE(idx, 0);
 	cft->seq_show = hugetlb_cgroup_read_numa_stat;
 
 	/* NULL terminate the last cft */
_

Patches currently in -mm which might be from xiujianfeng@huawei.com are

mm-hugetlb_cgroup-identify-the-legacy-using-cgroup_subsys_on_dfl.patch
mm-hugetlb_cgroup-prepare-cftypes-based-on-template.patch
mm-hugetlb_cgroup-switch-to-the-new-cftypes.patch