From: Matt Turner <mattst88@gmail.com>
To: linux-alpha@vger.kernel.org, richard.henderson@linaro.org
Cc: linmag7@gmail.com, linux-kernel@vger.kernel.org
Subject: [PATCH 16/24] alpha: select HAVE_GUP_FAST
Date: Tue, 1 Sep 2026 11:50:29 -0400 [thread overview]
Message-ID: <96d45353c7c29cc3aaa3234bd960f38d2ed8889f.1788277742.git.mattst88@gmail.com> (raw)
In-Reply-To: <cover.1788277742.git.mattst88@gmail.com>
The lockless GUP fast path needs the architecture to distinguish PTEs
with no struct page behind them and to keep page table pages alive while
a walker holds no lock. Alpha now has ARCH_HAS_PTE_SPECIAL, and it has
selected MMU_GATHER_RCU_TABLE_FREE for a long time, so both requirements
are met.
PTEs are a single 64-bit word on Alpha, so the lockless reads that the
generic walker performs cannot tear, and no arch-specific
gup_fast_permitted() or ptep_get_lockless() is needed.
Assisted-by: Claude:claude-opus-5
Signed-off-by: Matt Turner <mattst88@gmail.com>
---
arch/alpha/Kconfig | 1 +
1 file changed, 1 insertion(+)
diff --git ./arch/alpha/Kconfig ./arch/alpha/Kconfig
index 87fe81bc4709..352615956b1e 100644
--- ./arch/alpha/Kconfig
+++ ./arch/alpha/Kconfig
@@ -26,6 +26,7 @@ config ALPHA
select HAVE_ARCH_COMPILER_H
select HAVE_ASM_MODVERSIONS
select HAVE_DEBUG_KMEMLEAK
+ select HAVE_GUP_FAST
select HAVE_PAGE_SIZE_8KB
select HAVE_PCSPKR_PLATFORM
select HAVE_PERF_EVENTS
--
2.54.0
next prev parent reply other threads:[~2026-09-01 15:51 UTC|newest]
Thread overview: 51+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-01 15:50 [PATCH 00/24] alpha: catch up on architecture Kconfig options Matt Turner
2026-09-01 15:50 ` [PATCH 01/24] alpha: fix arch_irqs_disabled_flags() to treat any raised IPL as disabled Matt Turner
2026-09-01 23:20 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 02/24] alpha: enter hardirq context before looking up the irq descriptor Matt Turner
2026-09-03 22:07 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 03/24] alpha: select ARCH_HAS_UBSAN Matt Turner
2026-09-01 22:34 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 04/24] alpha: select ARCH_HAS_GCOV_PROFILE_ALL Matt Turner
2026-09-03 22:35 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 05/24] alpha: select HAVE_DEBUG_KMEMLEAK Matt Turner
2026-09-02 6:01 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 06/24] alpha: select EDAC_SUPPORT Matt Turner
2026-09-01 23:17 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 07/24] alpha: select ARCH_SUPPORTS_ATOMIC_RMW Matt Turner
2026-09-02 6:17 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 08/24] alpha: select ARCH_HAS_FAST_MULTIPLIER Matt Turner
2026-09-02 7:49 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 09/24] alpha: select ARCH_SUPPORTS_INT128 Matt Turner
2026-09-02 8:50 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 10/24] alpha: select HAVE_ARCH_COMPILER_H Matt Turner
2026-09-02 9:11 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 11/24] alpha: select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE Matt Turner
2026-09-02 9:25 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 12/24] alpha: add HAVE_ARCH_THREAD_STRUCT_WHITELIST support Matt Turner
2026-09-02 9:35 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 13/24] alpha: add ARCH_HAS_PTE_SPECIAL support Matt Turner
2026-09-02 9:42 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 14/24] alpha: add ARCH_SUPPORTS_PAGE_TABLE_CHECK support Matt Turner
2026-09-01 22:45 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 15/24] alpha: select ARCH_HAS_DEBUG_VM_PGTABLE Matt Turner
2026-09-03 22:52 ` Magnus Lindholm
2026-09-01 15:50 ` Matt Turner [this message]
2026-09-02 21:09 ` [PATCH 16/24] alpha: select HAVE_GUP_FAST Magnus Lindholm
2026-09-01 15:50 ` [PATCH 17/24] alpha: select ARCH_USE_MEMTEST Matt Turner
2026-09-02 21:56 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 18/24] alpha: select SYSCTL_EXCEPTION_TRACE Matt Turner
2026-09-02 22:02 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 19/24] alpha: discard .eh_frame and the relocation sections Matt Turner
2026-09-03 5:18 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 20/24] alpha: select ARCH_WANT_LD_ORPHAN_WARN Matt Turner
2026-09-03 5:34 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 21/24] alpha: select ARCH_WANT_IRQS_OFF_ACTIVATE_MM Matt Turner
2026-09-03 5:42 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 22/24] alpha: add HAVE_PERF_REGS and HAVE_PERF_USER_STACK_DUMP support Matt Turner
2026-09-03 21:01 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 23/24] alpha: select SPARSE_IRQ Matt Turner
2026-09-03 21:26 ` Magnus Lindholm
2026-09-01 15:50 ` [PATCH 24/24] alpha: add TRACE_IRQFLAGS_SUPPORT Matt Turner
2026-09-03 22:58 ` Magnus Lindholm
2026-09-02 18:53 ` [PATCH 00/24] alpha: catch up on architecture Kconfig options Magnus Lindholm
2026-09-02 18:57 ` Matt Turner
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=96d45353c7c29cc3aaa3234bd960f38d2ed8889f.1788277742.git.mattst88@gmail.com \
--to=mattst88@gmail.com \
--cc=linmag7@gmail.com \
--cc=linux-alpha@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=richard.henderson@linaro.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox