From:   Vlastimil Babka <vbabka@suse.cz>
To:     Christoph Lameter <cl@linux.com>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Pekka Enberg <penberg@kernel.org>
Cc:     Hyeonggon Yoo <42.hyeyoo@gmail.com>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        rcu@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org, patches@lists.linux.dev,
        linux-doc@vger.kernel.org, Vlastimil Babka <vbabka@suse.cz>,
        Lorenzo Stoakes <lstoakes@gmail.com>
Subject: [PATCH v2 1/6] mm/slob: remove CONFIG_SLOB
Date:   Fri, 17 Mar 2023 11:43:02 +0100
Message-Id: <20230317104307.29328-2-vbabka@suse.cz>
In-Reply-To: <20230317104307.29328-1-vbabka@suse.cz>
References: <20230317104307.29328-1-vbabka@suse.cz>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Remove SLOB from Kconfig and Makefile. Everything under #ifdef
CONFIG_SLOB, and mm/slob.c is now dead code.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Acked-by: Lorenzo Stoakes <lstoakes@gmail.com>
---
 init/Kconfig               |  2 +-
 kernel/configs/tiny.config |  1 -
 mm/Kconfig                 | 22 ----------------------
 mm/Makefile                |  2 --
 4 files changed, 1 insertion(+), 26 deletions(-)

diff --git a/init/Kconfig b/init/Kconfig
index 1fb5f313d18f..72ac3f66bc27 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -973,7 +973,7 @@ config MEMCG
 
 config MEMCG_KMEM
 	bool
-	depends on MEMCG && !SLOB
+	depends on MEMCG
 	default y
 
 config BLK_CGROUP
diff --git a/kernel/configs/tiny.config b/kernel/configs/tiny.config
index c2f9c912df1c..144b2bd86b14 100644
--- a/kernel/configs/tiny.config
+++ b/kernel/configs/tiny.config
@@ -7,6 +7,5 @@ CONFIG_KERNEL_XZ=y
 # CONFIG_KERNEL_LZO is not set
 # CONFIG_KERNEL_LZ4 is not set
 # CONFIG_SLAB is not set
-# CONFIG_SLOB_DEPRECATED is not set
 CONFIG_SLUB=y
 CONFIG_SLUB_TINY=y
diff --git a/mm/Kconfig b/mm/Kconfig
index 4751031f3f05..669399ab693c 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -238,30 +238,8 @@ config SLUB
 	   and has enhanced diagnostics. SLUB is the default choice for
 	   a slab allocator.
 
-config SLOB_DEPRECATED
-	depends on EXPERT
-	bool "SLOB (Simple Allocator - DEPRECATED)"
-	depends on !PREEMPT_RT
-	help
-	   Deprecated and scheduled for removal in a few cycles. SLUB
-	   recommended as replacement. CONFIG_SLUB_TINY can be considered
-	   on systems with 16MB or less RAM.
-
-	   If you need SLOB to stay, please contact linux-mm@kvack.org and
-	   people listed in the SLAB ALLOCATOR section of MAINTAINERS file,
-	   with your use case.
-
-	   SLOB replaces the stock allocator with a drastically simpler
-	   allocator. SLOB is generally more space efficient but
-	   does not perform as well on large systems.
-
 endchoice
 
-config SLOB
-	bool
-	default y
-	depends on SLOB_DEPRECATED
-
 config SLUB_TINY
 	bool "Configure SLUB for minimal memory footprint"
 	depends on SLUB && EXPERT
diff --git a/mm/Makefile b/mm/Makefile
index 8e105e5b3e29..e347958fc6b2 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -22,7 +22,6 @@ KCSAN_INSTRUMENT_BARRIERS := y
 # flaky coverage that is not a function of syscall inputs. E.g. slab is out of
 # free pages, or a task is migrated between nodes.
 KCOV_INSTRUMENT_slab_common.o := n
-KCOV_INSTRUMENT_slob.o := n
 KCOV_INSTRUMENT_slab.o := n
 KCOV_INSTRUMENT_slub.o := n
 KCOV_INSTRUMENT_page_alloc.o := n
@@ -81,7 +80,6 @@ obj-$(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP)	+= hugetlb_vmemmap.o
 obj-$(CONFIG_NUMA) 	+= mempolicy.o
 obj-$(CONFIG_SPARSEMEM)	+= sparse.o
 obj-$(CONFIG_SPARSEMEM_VMEMMAP) += sparse-vmemmap.o
-obj-$(CONFIG_SLOB) += slob.o
 obj-$(CONFIG_MMU_NOTIFIER) += mmu_notifier.o
 obj-$(CONFIG_KSM) += ksm.o
 obj-$(CONFIG_PAGE_POISONING) += page_poison.o
-- 
2.39.2