[PATCH 0/5] remove tlb_remove_page_ptdesc()

From: Qi Zheng <zhengqi.arch@bytedance.com>
To: peterz@infradead.org, kevin.brodsky@arm.com, riel@surriel.com,
	vishal.moola@gmail.com, david@redhat.com, jannh@google.com,
	hughd@google.com, willy@infradead.org, yuzhao@google.com,
	muchun.song@linux.dev, akpm@linux-foundation.org,
	will@kernel.org, aneesh.kumar@kernel.org, npiggin@gmail.com,
	arnd@arndb.de, dave.hansen@linux.intel.com, rppt@kernel.org,
	alexghiti@rivosinc.com
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org,
	linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org,
	loongarch@lists.linux.dev, linux-m68k@lists.linux-m68k.org,
	linux-mips@vger.kernel.org, linux-openrisc@vger.kernel.org,
	linux-sh@vger.kernel.org, linux-um@lists.infradead.org,
	x86@kernel.org, linux-riscv@lists.infradead.org,
	Qi Zheng <zhengqi.arch@bytedance.com>
Subject: [PATCH 0/5] remove tlb_remove_page_ptdesc()
Date: Thu, 23 Jan 2025 21:26:13 +0800	[thread overview]
Message-ID: <cover.1737637631.git.zhengqi.arch@bytedance.com> (raw)

Hi all,

As suggested by Peter Zijlstra below [1], this series aims to remove
tlb_remove_page_ptdesc().

: Fundamentally tlb_remove_page() is about removing *pages* as from a PTE,
: there should not be a page-table anywhere near here *ever*.
:
: Yes, some architectures use tlb_remove_page() for page-tables too, but
: that is more or less an implementation detail that can be fixed.

After this series, all architectures use tlb_remove_table() or tlb_remove_ptdesc()
to remove the page table pages. In the future, once all architectures using
tlb_remove_table() have also converted to using struct ptdesc (eg. powerpc), it
may be possible to use only tlb_remove_ptdesc().

Note: there will be some overlap between my patch #4 and Rik van Riel's patch #1 [2],
      once his patch is merged into the next branch, I can rebase onto his patch.
      And patch #4 can actually make x86 use tlb_remove_ptdesc(), but due to the
      above situation, I have not done so yet.

This series is based on next-20250122.

Comments and suggestions are welcome!

Thanks,
Qi

[1]. https://lore.kernel.org/linux-mm/20250103111457.GC22934@noisy.programming.kicks-ass.net/
[2]. https://lore.kernel.org/lkml/20250123042447.2259648-2-riel@surriel.com/

Qi Zheng (5):
  mm: pgtable: make generic tlb_remove_table() use struct ptdesc
  mm: pgtable: convert some architectures to use tlb_remove_ptdesc()
  riscv: pgtable: unconditionally use tlb_remove_ptdesc()
  x86: pgtable: unconditionally use tlb_remove_table()
  mm: pgtable: remove tlb_remove_page_ptdesc()

 arch/csky/include/asm/pgalloc.h      |  3 +--
 arch/hexagon/include/asm/pgalloc.h   |  3 +--
 arch/loongarch/include/asm/pgalloc.h |  3 +--
 arch/m68k/include/asm/sun3_pgalloc.h |  3 +--
 arch/mips/include/asm/pgalloc.h      |  3 +--
 arch/nios2/include/asm/pgalloc.h     |  9 ++++-----
 arch/openrisc/include/asm/pgalloc.h  |  3 +--
 arch/riscv/include/asm/pgalloc.h     | 26 ++++----------------------
 arch/sh/include/asm/pgalloc.h        |  3 +--
 arch/um/include/asm/pgalloc.h        |  9 +++------
 arch/x86/kernel/paravirt.c           | 17 +----------------
 arch/x86/mm/pgtable.c                | 11 -----------
 include/asm-generic/tlb.h            | 12 +++---------
 13 files changed, 22 insertions(+), 83 deletions(-)

-- 
2.20.1