From patchwork Sat May 24 00:11:48 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Richard Henderson X-Patchwork-Id: 1129 Received: (qmail 25694 invoked by alias); 24 May 2014 00:12:25 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 25585 invoked by uid 89); 24 May 2014 00:12:24 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-0.8 required=5.0 tests=AWL, BAYES_50, FREEMAIL_ENVFROM_END_DIGIT, FREEMAIL_FROM, RCVD_IN_DNSWL_NONE, SPF_PASS autolearn=no version=3.3.2 X-HELO: mail-qg0-f41.google.com X-Received: by 10.224.112.138 with SMTP id w10mr11753265qap.31.1400890340177; Fri, 23 May 2014 17:12:20 -0700 (PDT) From: Richard Henderson To: libc-alpha@sourceware.org Cc: marcus.shawcroft@gmail.com, Richard Henderson Subject: [PATCH v2 8/9] aarch64: Consolidate NPTL/non versions of clone Date: Fri, 23 May 2014 17:11:48 -0700 Message-Id: <1400890309-16710-9-git-send-email-rth@twiddle.net> In-Reply-To: <1400890309-16710-1-git-send-email-rth@twiddle.net> References: <1400890309-16710-1-git-send-email-rth@twiddle.net> From: Richard Henderson At the same time, rely on non-clobbered registers across syscall so that we eliminate the stack frame that we previously ignored in the unwind info. --- sysdeps/unix/sysv/linux/aarch64/clone.S | 56 ++++++++++++---------------- sysdeps/unix/sysv/linux/aarch64/nptl/clone.S | 21 ----------- 2 files changed, 24 insertions(+), 53 deletions(-) delete mode 100644 sysdeps/unix/sysv/linux/aarch64/nptl/clone.S diff --git a/sysdeps/unix/sysv/linux/aarch64/clone.S b/sysdeps/unix/sysv/linux/aarch64/clone.S index f2964f4..a2b5a2b 100644 --- a/sysdeps/unix/sysv/linux/aarch64/clone.S +++ b/sysdeps/unix/sysv/linux/aarch64/clone.S @@ -39,47 +39,42 @@ */ .text ENTRY(__clone) + /* Save args for the child. */ + mov x10, x0 + mov x11, x2 + mov x12, x3 + /* Sanity check args. */ - cbz x0, 1f - cbz x1, 1f - /* Insert the args onto the new stack. */ - stp x0, x3, [x1, #-16]! /* Fn, arg. */ + mov x0, #-EINVAL + cbz x10, .Lsyscall_error + cbz x1, .Lsyscall_error /* Do the system call. */ + /* X0:flags, x1:newsp, x2:parenttidptr, x3:newtls, x4:childtid. */ mov x0, x2 /* flags */ - /* New sp is already in x1. */ mov x2, x4 /* ptid */ mov x3, x5 /* tls */ mov x4, x6 /* ctid */ - -#ifdef RESET_PID - /* We rely on the kernel preserving the argument regsiters across a - each system call so that we can inspect the flags against after - the clone call. */ - mov x5, x0 -#endif - mov x8, #SYS_ify(clone) - /* X0:flags, x1:newsp, x2:parenttidptr, x3:newtls, x4:childtid. */ svc 0x0 - cfi_endproc + cmp x0, #0 - beq 2f - blt 3f + beq thread_start + blt .Lsyscall_error RET -1: mov x0, #-EINVAL -3: - b syscall_error +PSEUDO_END (__clone) -2: + .align 4 + .type thread_start, %function +thread_start: cfi_startproc cfi_undefined (x30) mov x29, 0 -#ifdef RESET_PID - tbnz x5, #CLONE_THREAD_BIT, 3f + + tbnz x11, #CLONE_THREAD_BIT, 3f mov x0, #-1 - tbnz x5, #CLONE_VM_BIT, 2f + tbnz x11, #CLONE_VM_BIT, 2f mov x8, #SYS_ify(getpid) svc 0x0 2: @@ -87,18 +82,15 @@ ENTRY(__clone) sub x1, x1, #PTHREAD_SIZEOF str w0, [x1, #PTHREAD_PID_OFFSET] str w0, [x1, #PTHREAD_TID_OFFSET] - 3: -#endif - /* Pick the function arg and call address from the stack and - execute. */ - ldp x1, x0, [sp], #16 - blr x1 + + /* Pick the function arg and execute. */ + mov x0, x12 + blr x10 /* We are done, pass the return value through x0. */ b HIDDEN_JUMPTARGET(_exit) cfi_endproc - cfi_startproc -PSEUDO_END (__clone) + .size thread_start, .-thread_start weak_alias (__clone, clone) diff --git a/sysdeps/unix/sysv/linux/aarch64/nptl/clone.S b/sysdeps/unix/sysv/linux/aarch64/nptl/clone.S deleted file mode 100644 index 281be3b..0000000 --- a/sysdeps/unix/sysv/linux/aarch64/nptl/clone.S +++ /dev/null @@ -1,21 +0,0 @@ -/* Copyright (C) 2009-2014 Free Software Foundation, Inc. - - This file is part of the GNU C Library. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public License as - published by the Free Software Foundation; either version 2.1 of the - License, or (at your option) any later version. - - The GNU C Library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; if not, see - . */ - -#define RESET_PID -#include -#include "../clone.S"