From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EA244202C29 for ; Wed, 8 Apr 2026 02:51:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775616706; cv=none; b=WaM02p4pm3Bd7vgBgpcwcnQls41mL2tmmb6MjKjdRQ0vhJfmWa0HdsK+DwrvCPGhdFI02KQOJc9dKUQbHGHa0GMF2KTXzKM3DcFxC48JyRGBc4G7Li8Td+wbkrArqplUsCEvqtMK8rV6LzmzvnjWQUIMw6rjEkolinW8wNy2FCg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775616706; c=relaxed/simple; bh=HLCqPTjcCmdnanlT8SVpYIjINZxqvkrrFi6ei5+WS7Q=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=DP++t2wcw7x2Ezk616cksz6jI200TR+NPvQzWCm6TX9dgNjgJMt7y5eNapuyt1XyJF5J9kjhkpvrj3tpA+Ja88hLTrUZ70L1DymgUMqFHqrrt1x2Ye0KOsHZChNIGEWRspm+e/tzeX4i/9/N1QlYiHLTvYYuJuP2LkZ6KQ95XA4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=E98cltUu; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="E98cltUu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D11D8C19421; Wed, 8 Apr 2026 02:51:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1775616705; bh=HLCqPTjcCmdnanlT8SVpYIjINZxqvkrrFi6ei5+WS7Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=E98cltUu5pz4jFx/09mSwR9dZ3lbqdssVOpqPjSPh9hhfM8JVF4YU+v01kkNe5m0H M0RZ2LNiEuLFM69/fPap3dkuh2UBPmIRHtnr+CBeOiAFjrpGGv0oL3Xhr/FrzVKUT+ 91SFi6HW5MU80MqN6PC15ebGS4uBiGtfv3eSIjPApij0yY3mF0grfx6pFmmBryGNDX T4dg3i6bfttSbwFHZTbPPIXkwMYYxc67fZY9aFx5k7ksURsZp6MEHkTE6CFq65amCg aiuuBvwfHF0QXa0S1PqSec3wkI9cH1pU6AY+Nn90uFLsSYE1BRNiXXttGTcot4Fmbx dkSeaxzsotkdg== From: "Barry Song (Xiaomi)" To: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, catalin.marinas@arm.com, will@kernel.org, akpm@linux-foundation.org, urezki@gmail.com Cc: linux-kernel@vger.kernel.org, anshuman.khandual@arm.com, ryan.roberts@arm.com, ajd@linux.ibm.com, rppt@kernel.org, david@kernel.org, Xueyuan.chen21@gmail.com, "Barry Song (Xiaomi)" Subject: [RFC PATCH 4/8] mm/vmalloc: Eliminate page table zigzag for huge vmalloc mappings Date: Wed, 8 Apr 2026 10:51:11 +0800 Message-Id: <20260408025115.27368-5-baohua@kernel.org> X-Mailer: git-send-email 2.39.3 (Apple Git-146) In-Reply-To: <20260408025115.27368-1-baohua@kernel.org> References: <20260408025115.27368-1-baohua@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit For vmalloc() allocations with VM_ALLOW_HUGE_VMAP, we no longer need to iterate over pages one by one, which would otherwise lead to zigzag page table mappings. The code is now unified with the PAGE_SHIFT case by simply calling vmap_small_pages_range_noflush(). Signed-off-by: Barry Song (Xiaomi) --- mm/vmalloc.c | 22 ++++------------------ 1 file changed, 4 insertions(+), 18 deletions(-) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 5bf072297536..eba436386929 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -689,27 +689,13 @@ static int vmap_small_pages_range_noflush(unsigned long addr, unsigned long end, int __vmap_pages_range_noflush(unsigned long addr, unsigned long end, pgprot_t prot, struct page **pages, unsigned int page_shift) { - unsigned int i, nr = (end - addr) >> PAGE_SHIFT; - WARN_ON(page_shift < PAGE_SHIFT); - if (!IS_ENABLED(CONFIG_HAVE_ARCH_HUGE_VMALLOC) || - page_shift == PAGE_SHIFT) - return vmap_small_pages_range_noflush(addr, end, prot, pages, PAGE_SHIFT); - - for (i = 0; i < nr; i += 1U << (page_shift - PAGE_SHIFT)) { - int err; - - err = vmap_range_noflush(addr, addr + (1UL << page_shift), - page_to_phys(pages[i]), prot, - page_shift); - if (err) - return err; + if (!IS_ENABLED(CONFIG_HAVE_ARCH_HUGE_VMALLOC)) + page_shift = PAGE_SHIFT; - addr += 1UL << page_shift; - } - - return 0; + return vmap_small_pages_range_noflush(addr, end, prot, pages, + min(page_shift, PMD_SHIFT)); } int vmap_pages_range_noflush(unsigned long addr, unsigned long end, -- 2.39.3 (Apple Git-146)