From: David Laight <david.laight.linux@gmail.com>
To: Yeoreum Yun <yeoreum.yun@arm.com>
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Subject: Re: [RFC PATCH 02/34] ARM: mm: make 2-level pgd_t a scalar
Date: Tue, 14 Jul 2026 13:34:15 +0100 [thread overview]
Message-ID: <20260714133415.78e25654@pumpkin> (raw)
In-Reply-To: <20260713135614.1618183-3-yeoreum.yun@arm.com>
On Mon, 13 Jul 2026 14:55:41 +0100
Yeoreum Yun <yeoreum.yun@arm.com> wrote:
> From: "David Hildenbrand (Arm)" <david@kernel.org>
>
> We don't want pgd_t to be an array, as it prohibits returning it from a
> function, like pgdp_get().
If you use a two element structure the compiler/ABI might be able to
return that from a function in two registers.
That might make the entire mess more readable ...
David
next prev parent reply other threads:[~2026-07-14 12:34 UTC|newest]
Thread overview: 54+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-07-13 13:55 [RFC PATCH 00/34] mm: optimize unnecessary loads due to ptep_get() and friends out Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 01/34] ARM: mm: make nommu pgd_t a scalar Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 02/34] ARM: mm: make 2-level " Yeoreum Yun
2026-07-13 15:38 ` Arnd Bergmann
2026-07-13 16:04 ` David Hildenbrand (Arm)
2026-07-13 16:26 ` David Hildenbrand (Arm)
2026-07-14 10:26 ` Pedro Falcato
2026-07-14 10:54 ` David Hildenbrand (Arm)
2026-07-14 11:55 ` Arnd Bergmann
2026-07-14 13:34 ` David Laight
2026-07-14 12:34 ` David Laight [this message]
2026-07-14 13:03 ` David Hildenbrand (Arm)
2026-07-13 13:55 ` [RFC PATCH 03/34] ARM: mm: remove custom pgdp_get() Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 04/34] LoongArch: mm: define pud_leaf() only when PUD exists Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 05/34] MIPS: " Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 06/34] mm/pgtable: define (pgd|p4d|pud)_leaf() for folded page tables Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 07/34] mm/pgtable: define (pgd|p4d|pud)_offset_lockless() " Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 08/34] loongarch: kvm: remove stack copy address of pXd in pXd_offset() Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 09/34] riscv: " Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 10/34] x86: mm: carve out the generic compile-time folded pgtable case in effective_prot() Yeoreum Yun
2026-07-13 14:19 ` Dave Hansen
2026-07-13 14:41 ` David Hildenbrand (Arm)
2026-07-13 14:55 ` Dave Hansen
2026-07-13 15:02 ` David Hildenbrand (Arm)
2026-07-13 17:57 ` Dave Hansen
2026-07-13 19:49 ` David Hildenbrand (Arm)
2026-07-13 20:27 ` Dave Hansen
2026-07-13 21:17 ` David Hildenbrand (Arm)
2026-07-13 21:40 ` Dave Hansen
2026-07-14 10:50 ` David Hildenbrand (Arm)
2026-07-14 11:40 ` Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 11/34] mm: vmscan: remove stack copy address of pud pass in wallk_pud_range() Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 13/34] arm64: mm: define pud_set_huge() when __PGTABLE_PMD_FOLDED not defined Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 14/34] csky: mm: use proper set_pXd() for generic compile-time folded patable in vmalloc_fault() Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 15/34] mips: mm: use proper set_pXd() for generic compile-time folded patable in vmalloc_fault path Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 16/34] nios2: " Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 17/34] riscv: mm: use proper set_pXd() for generic compile-time folded patable in vmalloc_fault() Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 18/34] riscv: mm: use proper set_pXd() for generic compile-time folded patable in setup_vm_final() Yeoreum Yun
2026-07-13 13:55 ` [RFC PATCH 19/34] x86: power: use proper set_pXd() for generic compile-time folded patable in resume_one_md_table_init() Yeoreum Yun
[not found] ` <595e5ba5-0bc4-4630-b8f0-8637298076ce@intel.com>
2026-07-13 14:59 ` David Hildenbrand (Arm)
2026-07-13 15:01 ` Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 21/34] x86: platform: use proper set_pXd() for generic compile-time folded patable in setup_olpc_ofw_pgd() Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 22/34] x86: mm: use proper set_pXd() for generic compile-time folded patable in one_md_table_init() Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 23/34] x86: mm: skip pud setup when using generic compile-time folded pagetable Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 24/34] x86: mm: call try_to_free_pmd_page() when CONFIG_PGTABLE_LEVELS > 2 Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 27/34] m68k: mm: remove usage of pgd_page_vaddr() for CONFIG_PGTABLE_LEVELS=3 Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 28/34] arm: mm: use proper pgtable APIs for generic compile-time folded patable in kasan_init() Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 29/34] mm/pgtable: disallow calling folded set_pgd/set_p4d/set_pud Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 30/34] mm/pgtable: disallow calling folded (pgd|p4d|pud)_page, pgd_page_vaddr() and (p4d|pud)_pgtable Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 31/34] mm/pgtable: optimize pmdp_get() and friends for folded pagetable levels Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 32/34] openrisc/pgtable: drop __pmd_offset() Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 33/34] mm/pgtable: catch abuse of folded dummy pgd_t/p4d_t/pud_t Yeoreum Yun
2026-07-13 13:56 ` [RFC PATCH 34/34] arm64: pgtable: convert pte_present() from macro to static inline Yeoreum Yun
2026-07-13 14:08 ` [RFC PATCH 00/34] mm: optimize unnecessary loads due to ptep_get() and friends out David Hildenbrand (Arm)
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