From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751827AbeFBMos (ORCPT ); Sat, 2 Jun 2018 08:44:48 -0400 Received: from mail.efficios.com ([167.114.142.138]:42754 "EHLO mail.efficios.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751603AbeFBMoa (ORCPT ); Sat, 2 Jun 2018 08:44:30 -0400 DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com 26E451A85E2 From: Mathieu Desnoyers To: Peter Zijlstra , "Paul E . McKenney" , Boqun Feng , Andy Lutomirski , Dave Watson Cc: linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, Paul Turner , Andrew Morton , Russell King , Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" , Andrew Hunter , Andi Kleen , Chris Lameter , Ben Maurer , Steven Rostedt , Josh Triplett , Linus Torvalds , Catalin Marinas , Will Deacon , Michael Kerrisk , Joel Fernandes , Mathieu Desnoyers Subject: [RFC PATCH for 4.18 07/16] x86: Wire up restartable sequence system call Date: Sat, 2 Jun 2018 08:43:59 -0400 Message-Id: <20180602124408.8430-8-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20180602124408.8430-1-mathieu.desnoyers@efficios.com> References: <20180602124408.8430-1-mathieu.desnoyers@efficios.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Wire up the rseq system call on x86 32/64. This provides an ABI improving the speed of a user-space getcpu operation on x86 by removing the need to perform a function call, "lsl" instruction, or system call on the fast path, as well as improving the speed of user-space operations on per-cpu data. Signed-off-by: Mathieu Desnoyers Reviewed-by: Thomas Gleixner CC: Russell King CC: Catalin Marinas CC: Will Deacon CC: Paul Turner CC: Andrew Hunter CC: Peter Zijlstra CC: Andy Lutomirski CC: Andi Kleen CC: Dave Watson CC: Chris Lameter CC: Ingo Molnar CC: "H. Peter Anvin" CC: Ben Maurer CC: Steven Rostedt CC: "Paul E. McKenney" CC: Josh Triplett CC: Linus Torvalds CC: Andrew Morton CC: Boqun Feng CC: linux-api@vger.kernel.org --- arch/x86/entry/syscalls/syscall_32.tbl | 1 + arch/x86/entry/syscalls/syscall_64.tbl | 1 + 2 files changed, 2 insertions(+) diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl index d6b27dab1b30..db346da64947 100644 --- a/arch/x86/entry/syscalls/syscall_32.tbl +++ b/arch/x86/entry/syscalls/syscall_32.tbl @@ -396,3 +396,4 @@ 382 i386 pkey_free sys_pkey_free __ia32_sys_pkey_free 383 i386 statx sys_statx __ia32_sys_statx 384 i386 arch_prctl sys_arch_prctl __ia32_compat_sys_arch_prctl +385 i386 rseq sys_rseq __ia32_sys_rseq diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl index 4dfe42666d0c..41b082b125c3 100644 --- a/arch/x86/entry/syscalls/syscall_64.tbl +++ b/arch/x86/entry/syscalls/syscall_64.tbl @@ -341,6 +341,7 @@ 330 common pkey_alloc __x64_sys_pkey_alloc 331 common pkey_free __x64_sys_pkey_free 332 common statx __x64_sys_statx +333 common rseq __x64_sys_rseq # # x32-specific system call numbers start at 512 to avoid cache impact -- 2.11.0