From: Qi Zheng <zhengqi.arch@bytedance.com>
Date: Tue, 27 Jan 2026 12:12:54 +0000 (+0800)
Subject: mm: change mm/pt_reclaim.c to use asm/tlb.h instead of asm-generic/tlb.h
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d8b65654b16f0cab24f1c46f9aed5562a8513da6;p=thirdparty%2Fkernel%2Fstable.git

mm: change mm/pt_reclaim.c to use asm/tlb.h instead of asm-generic/tlb.h

Patch series "enable PT_RECLAIM on more 64-bit architectures", v4.

This series aims to enable PT_RECLAIM on more 64-bit architectures.

On a 64-bit system, madvise(MADV_DONTNEED) may cause a large number of
empty PTE page table pages (such as 100GB+).  To resolve this problem, we
need to enable PT_RECLAIM, which depends on MMU_GATHER_RCU_TABLE_FREE.

For these architectures that define its own __tlb_remove_table(), since
their page tables are not of type struct ptdesc, they cannot be supported
PT_RECLAIM.

Therefore, this series first enables MMU_GATHER_RCU_TABLE_FREE on all
64-bit architectures, then converts __HAVE_ARCH_TLB_REMOVE_TABLE to
CONFIG_HAVE_ARCH_TLB_REMOVE_TABLE config, and finally makes PT_RECLAIM
depend on MMU_GATHER_RCU_TABLE_FREE && !HAVE_ARCH_TLB_REMOVE_TABLE.  This
way, PT_RECLAIM can be enabled by default on most 64-bit architectures.

Of course, this will also be enabled on some 32-bit architectures that
already support MMU_GATHER_RCU_TABLE_FREE.  That's fine, PT_RECLAIM works
well on all 32-bit architectures as well.  Although the benefit isn't
significant, there's still memory that can be reclaimed.  Perhaps
PT_RECLAIM can be enabled on all 32-bit architectures in the future.


This patch (of 8):

Generally, the asm/tlb.h will include asm-generic/tlb.h, so change
mm/pt_reclaim.c to use asm/tlb.h instead of asm-generic/tlb.h.  This is a
preparation for enabling CONFIG_PT_RECLAIM on other architectures, such as
alpha.

Link: https://lkml.kernel.org/r/cover.1769515122.git.zhengqi.arch@bytedance.com
Link: https://lkml.kernel.org/r/befca537d10c6bf8d531b1ee0a8af1e3b31352b0.1769515122.git.zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lance Yang <ioworker0@gmail.com>
Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Magnus Lindholm <linmag7@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Gleixner <tglx@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Will Deacon <will@kernel.org>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: WANG Xuerui <kernel@xen0n.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/mm/pt_reclaim.c b/mm/pt_reclaim.c
index 0d9cfbf4fe5d..46771cfff823 100644
--- a/mm/pt_reclaim.c
+++ b/mm/pt_reclaim.c
@@ -2,7 +2,7 @@
 #include <linux/hugetlb.h>
 #include <linux/pgalloc.h>
 
-#include <asm-generic/tlb.h>
+#include <asm/tlb.h>
 
 #include "internal.h"