[PATCH 0/2] riscv: Enable percpu page first chunk allocator

From: Alexandre Ghiti <alexghiti@rivosinc.com>
To: Paul Walmsley <paul.walmsley@sifive.com>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Albert Ou <aou@eecs.berkeley.edu>,
	Andrey Ryabinin <ryabinin.a.a@gmail.com>,
	Alexander Potapenko <glider@google.com>,
	Andrey Konovalov <andreyknvl@gmail.com>,
	Dmitry Vyukov <dvyukov@google.com>,
	Vincenzo Frascino <vincenzo.frascino@arm.com>,
	Arnd Bergmann <arnd@arndb.de>, Dennis Zhou <dennis@kernel.org>,
	Tejun Heo <tj@kernel.org>, Christoph Lameter <cl@linux.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
	kasan-dev@googlegroups.com, linux-arch@vger.kernel.org,
	linux-mm@kvack.org
Cc: Alexandre Ghiti <alexghiti@rivosinc.com>
Subject: [PATCH 0/2] riscv: Enable percpu page first chunk allocator
Date: Fri, 10 Nov 2023 15:07:19 +0100	[thread overview]
Message-ID: <20231110140721.114235-1-alexghiti@rivosinc.com> (raw)

While working with pcpu variables, I noticed that riscv did not support
first chunk allocation in the vmalloc area which may be needed as a fallback
in case of a sparse NUMA configuration.

patch 1 starts by introducing a new function flush_cache_vmap_early() which
is needed since a new vmalloc mapping is established and directly accessed:
on riscv, this would likely fail in case of a reordered access or if the
uarch caches invalid entries in TLB.

patch 2 simply enables the page percpu first chunk allocator in riscv.

Alexandre Ghiti (2):
  mm: Introduce flush_cache_vmap_early() and its riscv implementation
  riscv: Enable pcpu page first chunk allocator

 arch/riscv/Kconfig                  | 2 ++
 arch/riscv/include/asm/cacheflush.h | 3 ++-
 arch/riscv/include/asm/tlbflush.h   | 2 ++
 arch/riscv/mm/kasan_init.c          | 8 ++++++++
 arch/riscv/mm/tlbflush.c            | 5 +++++
 include/asm-generic/cacheflush.h    | 6 ++++++
 mm/percpu.c                         | 8 +-------
 7 files changed, 26 insertions(+), 8 deletions(-)

-- 
2.39.2