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 976A914C5B3 for ; Wed, 3 Apr 2024 20:48:30 +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=1712177311; cv=none; b=djvgzXXOlh0nozYREd555VD8bVjIT6x+RW/O7hz4vpdHuDx3hI1n9/PLbPKALbU/R/7N4Cj6XhDX1fSftndKQWCMVr3c19dj/QGkF55kXMz0A1oklXoV0ZYqjXV3TWHnl16h6rhJB7cyZqmxWcAYtNLIHIU3Wv3pboVYuOFLVAo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712177311; c=relaxed/simple; bh=1dlxVy0ngy+HgoVicNZ1BcqWIWrEnhLRDERZKJIXYig=; h=Date:To:From:Subject:Message-Id; b=ogNZLDAr0SCK/1WHLIVFd9qpgwW4bZwgFa8x/NfET5/4WSJNvjGmQWPHN5+NxLH+JghhJDo8DZcrsLlGP3lSpauqU6agAglTtjGXxMNtXDhMdN6/cWvXPX7pT6s1s+mD7Y/i6x+56pmT6cRHT8vXvBehujbxfxqNCYZgcv0pVV4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=AUAsJSRa; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="AUAsJSRa" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6E2C4C43390; Wed, 3 Apr 2024 20:48:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1712177310; bh=1dlxVy0ngy+HgoVicNZ1BcqWIWrEnhLRDERZKJIXYig=; h=Date:To:From:Subject:From; b=AUAsJSRa1e0S4P92fHZ5evpD73sH85qULoTSPaaHdkPHeqNM/5pbdV68LOvjN7rKn 9NzDWSB5hNkPKwy1R9BI5NRk5MggrltoHl5V0cUbHeE1TnhCFC8hPTIevg3wREsRIB k5elNbqsI9GE0Lam94NjK1eRAF3Suv4UjIzOjFx8= Date: Wed, 03 Apr 2024 13:48:29 -0700 To: mm-commits@vger.kernel.org,will@kernel.org,surenb@google.com,peterz@infradead.org,paul.walmsley@sifive.com,palmer@dabbelt.com,npiggin@gmail.com,mpe@ellerman.id.au,luto@kernel.org,linux@armlinux.org.uk,gerald.schaefer@linux.ibm.com,dave.hansen@linux.intel.com,christophe.leroy@csgroup.eu,catalin.marinas@arm.com,aou@eecs.berkeley.edu,agordeev@linux.ibm.com,wangkefeng.wang@huawei.com,akpm@linux-foundation.org From: Andrew Morton Subject: + arm64-mm-accelerate-pagefault-when-vm_fault_badaccess.patch added to mm-unstable branch Message-Id: <20240403204830.6E2C4C43390@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: arm64: mm: accelerate pagefault when VM_FAULT_BADACCESS has been added to the -mm mm-unstable branch. Its filename is arm64-mm-accelerate-pagefault-when-vm_fault_badaccess.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/arm64-mm-accelerate-pagefault-when-vm_fault_badaccess.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Kefeng Wang Subject: arm64: mm: accelerate pagefault when VM_FAULT_BADACCESS Date: Wed, 3 Apr 2024 16:38:00 +0800 The vm_flags of vma already checked under per-VMA lock, if it is a bad access, directly set fault to VM_FAULT_BADACCESS and handle error, no need to retry with mmap_lock again, the latency time reduces 34% in 'lat_sig -P 1 prot lat_sig' from lmbench testcase. Since the page fault is handled under per-VMA lock, count it as a vma lock event with VMA_LOCK_SUCCESS. Link: https://lkml.kernel.org/r/20240403083805.1818160-3-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Reviewed-by: Suren Baghdasaryan Cc: Albert Ou Cc: Alexander Gordeev Cc: Andy Lutomirski Cc: Catalin Marinas Cc: Christophe Leroy Cc: Dave Hansen Cc: Gerald Schaefer Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Russell King Cc: Will Deacon Signed-off-by: Andrew Morton --- arch/arm64/mm/fault.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/arch/arm64/mm/fault.c~arm64-mm-accelerate-pagefault-when-vm_fault_badaccess +++ a/arch/arm64/mm/fault.c @@ -572,7 +572,9 @@ static int __kprobes do_page_fault(unsig if (!(vma->vm_flags & vm_flags)) { vma_end_read(vma); - goto lock_mmap; + fault = VM_FAULT_BADACCESS; + count_vm_vma_lock_event(VMA_LOCK_SUCCESS); + goto done; } fault = handle_mm_fault(vma, addr, mm_flags | FAULT_FLAG_VMA_LOCK, regs); if (!(fault & (VM_FAULT_RETRY | VM_FAULT_COMPLETED))) _ Patches currently in -mm which might be from wangkefeng.wang@huawei.com are mm-backing-dev-use-group-allocation-free-of-per-cpu-counters-api.patch mm-remove-__set_page_dirty_nobuffers.patch arm64-mm-cleanup-__do_page_fault.patch arm64-mm-accelerate-pagefault-when-vm_fault_badaccess.patch arm-mm-accelerate-pagefault-when-vm_fault_badaccess.patch powerpc-mm-accelerate-pagefault-when-badaccess.patch riscv-mm-accelerate-pagefault-when-badaccess.patch s390-mm-accelerate-pagefault-when-badaccess.patch x86-mm-accelerate-pagefault-when-badaccess.patch