Received-SPF: pass (google.com: domain of linux-kernel+bounces-62415-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) client-ip=2604:1380:45d1:ec00::1;
Date: Mon, 12 Feb 2024 13:38:55 -0800
In-Reply-To: <20240212213922.783301-1-surenb@google.com>
Precedence: bulk
Mime-Version: 1.0
References: <20240212213922.783301-1-surenb@google.com>
Message-ID: <20240212213922.783301-10-surenb@google.com>
Subject: [PATCH v3 09/35] slab: objext: introduce objext_flags as extension to page_memcg_data_flags
From: Suren Baghdasaryan <surenb@google.com>
To: akpm@linux-foundation.org
Cc: kent.overstreet@linux.dev, mhocko@suse.com, vbabka@suse.cz, 
	hannes@cmpxchg.org, roman.gushchin@linux.dev, mgorman@suse.de, 
	dave@stgolabs.net, willy@infradead.org, liam.howlett@oracle.com, 
	corbet@lwn.net, void@manifault.com, peterz@infradead.org, 
	juri.lelli@redhat.com, catalin.marinas@arm.com, will@kernel.org, 
	arnd@arndb.de, tglx@linutronix.de, mingo@redhat.com, 
	dave.hansen@linux.intel.com, x86@kernel.org, peterx@redhat.com, 
	david@redhat.com, axboe@kernel.dk, mcgrof@kernel.org, masahiroy@kernel.org, 
	nathan@kernel.org, dennis@kernel.org, tj@kernel.org, muchun.song@linux.dev, 
	rppt@kernel.org, paulmck@kernel.org, pasha.tatashin@soleen.com, 
	yosryahmed@google.com, yuzhao@google.com, dhowells@redhat.com, 
	hughd@google.com, andreyknvl@gmail.com, keescook@chromium.org, 
	ndesaulniers@google.com, vvvvvv@google.com, gregkh@linuxfoundation.org, 
	ebiggers@google.com, ytcoode@gmail.com, vincent.guittot@linaro.org, 
	dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, 
	bristot@redhat.com, vschneid@redhat.com, cl@linux.com, penberg@kernel.org, 
	iamjoonsoo.kim@lge.com, 42.hyeyoo@gmail.com, glider@google.com, 
	elver@google.com, dvyukov@google.com, shakeelb@google.com, 
	songmuchun@bytedance.com, jbaron@akamai.com, rientjes@google.com, 
	minchan@google.com, kaleshsingh@google.com, surenb@google.com, 
	kernel-team@android.com, linux-doc@vger.kernel.org, 
	linux-kernel@vger.kernel.org, iommu@lists.linux.dev, 
	linux-arch@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, 
	linux-modules@vger.kernel.org, kasan-dev@googlegroups.com, 
	cgroups@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"

Introduce objext_flags to store additional objext flags unrelated to memcg.

Signed-off-by: Suren Baghdasaryan <surenb@google.com>
---
 include/linux/memcontrol.h | 29 ++++++++++++++++++++++-------
 mm/slab.h                  |  4 +---
 2 files changed, 23 insertions(+), 10 deletions(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index eb1dc181e412..f3584e98b640 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -356,7 +356,22 @@ enum page_memcg_data_flags {
 	__NR_MEMCG_DATA_FLAGS  = (1UL << 2),
 };
 
-#define MEMCG_DATA_FLAGS_MASK (__NR_MEMCG_DATA_FLAGS - 1)
+#define __FIRST_OBJEXT_FLAG	__NR_MEMCG_DATA_FLAGS
+
+#else /* CONFIG_MEMCG */
+
+#define __FIRST_OBJEXT_FLAG	(1UL << 0)
+
+#endif /* CONFIG_MEMCG */
+
+enum objext_flags {
+	/* the next bit after the last actual flag */
+	__NR_OBJEXTS_FLAGS  = __FIRST_OBJEXT_FLAG,
+};
+
+#define OBJEXTS_FLAGS_MASK (__NR_OBJEXTS_FLAGS - 1)
+
+#ifdef CONFIG_MEMCG
 
 static inline bool folio_memcg_kmem(struct folio *folio);
 
@@ -390,7 +405,7 @@ static inline struct mem_cgroup *__folio_memcg(struct folio *folio)
 	VM_BUG_ON_FOLIO(memcg_data & MEMCG_DATA_OBJEXTS, folio);
 	VM_BUG_ON_FOLIO(memcg_data & MEMCG_DATA_KMEM, folio);
 
-	return (struct mem_cgroup *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
+	return (struct mem_cgroup *)(memcg_data & ~OBJEXTS_FLAGS_MASK);
 }
 
 /*
@@ -411,7 +426,7 @@ static inline struct obj_cgroup *__folio_objcg(struct folio *folio)
 	VM_BUG_ON_FOLIO(memcg_data & MEMCG_DATA_OBJEXTS, folio);
 	VM_BUG_ON_FOLIO(!(memcg_data & MEMCG_DATA_KMEM), folio);
 
-	return (struct obj_cgroup *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
+	return (struct obj_cgroup *)(memcg_data & ~OBJEXTS_FLAGS_MASK);
 }
 
 /*
@@ -468,11 +483,11 @@ static inline struct mem_cgroup *folio_memcg_rcu(struct folio *folio)
 	if (memcg_data & MEMCG_DATA_KMEM) {
 		struct obj_cgroup *objcg;
 
-		objcg = (void *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
+		objcg = (void *)(memcg_data & ~OBJEXTS_FLAGS_MASK);
 		return obj_cgroup_memcg(objcg);
 	}
 
-	return (struct mem_cgroup *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
+	return (struct mem_cgroup *)(memcg_data & ~OBJEXTS_FLAGS_MASK);
 }
 
 /*
@@ -511,11 +526,11 @@ static inline struct mem_cgroup *folio_memcg_check(struct folio *folio)
 	if (memcg_data & MEMCG_DATA_KMEM) {
 		struct obj_cgroup *objcg;
 
-		objcg = (void *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
+		objcg = (void *)(memcg_data & ~OBJEXTS_FLAGS_MASK);
 		return obj_cgroup_memcg(objcg);
 	}
 
-	return (struct mem_cgroup *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
+	return (struct mem_cgroup *)(memcg_data & ~OBJEXTS_FLAGS_MASK);
 }
 
 static inline struct mem_cgroup *page_memcg_check(struct page *page)
diff --git a/mm/slab.h b/mm/slab.h
index f4ff635091e4..77cf7474fe46 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -560,10 +560,8 @@ static inline struct slabobj_ext *slab_obj_exts(struct slab *slab)
 							slab_page(slab));
 	VM_BUG_ON_PAGE(obj_exts & MEMCG_DATA_KMEM, slab_page(slab));
 
-	return (struct slabobj_ext *)(obj_exts & ~MEMCG_DATA_FLAGS_MASK);
-#else
-	return (struct slabobj_ext *)obj_exts;
 #endif
+	return (struct slabobj_ext *)(obj_exts & ~OBJEXTS_FLAGS_MASK);
 }
 
 int alloc_slab_obj_exts(struct slab *slab, struct kmem_cache *s,
-- 
2.43.0.687.g38aa6559b0-goog