From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 48461C433DB for ; Tue, 26 Jan 2021 06:50:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F30DC22228 for ; Tue, 26 Jan 2021 06:50:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729782AbhAZGuY (ORCPT ); Tue, 26 Jan 2021 01:50:24 -0500 Received: from pegase1.c-s.fr ([93.17.236.30]:20189 "EHLO pegase1.c-s.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729781AbhAYOv0 (ORCPT ); Mon, 25 Jan 2021 09:51:26 -0500 Received: from localhost (mailhub1-int [192.168.12.234]) by localhost (Postfix) with ESMTP id 4DPXmS1NGMz9v0Hl; Mon, 25 Jan 2021 15:48:24 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at c-s.fr Received: from pegase1.c-s.fr ([192.168.12.234]) by localhost (pegase1.c-s.fr [192.168.12.234]) (amavisd-new, port 10024) with ESMTP id EkPXsMuex3eP; Mon, 25 Jan 2021 15:48:24 +0100 (CET) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase1.c-s.fr (Postfix) with ESMTP id 4DPXmS0365z9v0Hk; Mon, 25 Jan 2021 15:48:24 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 895728B79E; Mon, 25 Jan 2021 15:48:29 +0100 (CET) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id cE-EMZBN0A4D; Mon, 25 Jan 2021 15:48:29 +0100 (CET) Received: from po16121vm.idsi0.si.c-s.fr (po15451.idsi0.si.c-s.fr [172.25.230.103]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 5A8A38B79B; Mon, 25 Jan 2021 15:48:29 +0100 (CET) Received: by po16121vm.idsi0.si.c-s.fr (Postfix, from userid 0) id 4EE1F66AD8; Mon, 25 Jan 2021 14:48:29 +0000 (UTC) Message-Id: <35e22ae59d0e1810ab7954918bdb1078b06d6bbd.1611585031.git.christophe.leroy@csgroup.eu> In-Reply-To: References: From: Christophe Leroy Subject: [PATCH v4 16/23] powerpc/32: Always save non volatile GPRs at syscall entry To: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , npiggin@gmail.com, msuchanek@suse.de Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Date: Mon, 25 Jan 2021 14:48:29 +0000 (UTC) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In preparation for porting syscall entry/exit to C, inconditionally save non volatile general purpose registers. Commit 965dd3ad3076 ("powerpc/64/syscall: Remove non-volatile GPR save optimisation") provides detailed explanation. This increases the number of cycles by 24 cycles on 8xx with null_syscall benchmark (280 => 304 cycles) Signed-off-by: Christophe Leroy --- arch/powerpc/kernel/entry_32.S | 46 +----------------------- arch/powerpc/kernel/head_32.h | 2 +- arch/powerpc/kernel/head_booke.h | 2 +- arch/powerpc/kernel/syscalls/syscall.tbl | 20 +++-------- 4 files changed, 8 insertions(+), 62 deletions(-) diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index b1e36602c013..97dc28a68465 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -351,6 +351,7 @@ trace_syscall_entry_irq_off: .globl transfer_to_syscall transfer_to_syscall: + SAVE_NVGPRS(r1) #ifdef CONFIG_PPC_BOOK3S_32 kuep_lock r11, r12 #endif @@ -614,51 +615,6 @@ ret_from_kernel_syscall: #endif _ASM_NOKPROBE_SYMBOL(ret_from_kernel_syscall) -/* - * The fork/clone functions need to copy the full register set into - * the child process. Therefore we need to save all the nonvolatile - * registers (r13 - r31) before calling the C code. - */ - .globl ppc_fork -ppc_fork: - SAVE_NVGPRS(r1) - lwz r0,_TRAP(r1) - rlwinm r0,r0,0,0,30 /* clear LSB to indicate full */ - stw r0,_TRAP(r1) /* register set saved */ - b sys_fork - - .globl ppc_vfork -ppc_vfork: - SAVE_NVGPRS(r1) - lwz r0,_TRAP(r1) - rlwinm r0,r0,0,0,30 /* clear LSB to indicate full */ - stw r0,_TRAP(r1) /* register set saved */ - b sys_vfork - - .globl ppc_clone -ppc_clone: - SAVE_NVGPRS(r1) - lwz r0,_TRAP(r1) - rlwinm r0,r0,0,0,30 /* clear LSB to indicate full */ - stw r0,_TRAP(r1) /* register set saved */ - b sys_clone - - .globl ppc_clone3 -ppc_clone3: - SAVE_NVGPRS(r1) - lwz r0,_TRAP(r1) - rlwinm r0,r0,0,0,30 /* clear LSB to indicate full */ - stw r0,_TRAP(r1) /* register set saved */ - b sys_clone3 - - .globl ppc_swapcontext -ppc_swapcontext: - SAVE_NVGPRS(r1) - lwz r0,_TRAP(r1) - rlwinm r0,r0,0,0,30 /* clear LSB to indicate full */ - stw r0,_TRAP(r1) /* register set saved */ - b sys_swapcontext - /* * Top-level page fault handling. * This is in assembler because if do_page_fault tells us that diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h index 24dc326e0d56..7b12736ec546 100644 --- a/arch/powerpc/kernel/head_32.h +++ b/arch/powerpc/kernel/head_32.h @@ -148,7 +148,7 @@ stw r2,GPR2(r11) addi r10,r10,STACK_FRAME_REGS_MARKER@l stw r9,_MSR(r11) - li r2, \trapno + 1 + li r2, \trapno stw r10,8(r11) stw r2,_TRAP(r11) SAVE_GPR(0, r11) diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h index b3c502c503a0..626e716576ce 100644 --- a/arch/powerpc/kernel/head_booke.h +++ b/arch/powerpc/kernel/head_booke.h @@ -124,7 +124,7 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV) stw r2,GPR2(r11) addi r12, r12, STACK_FRAME_REGS_MARKER@l stw r9,_MSR(r11) - li r2, \trapno + 1 + li r2, \trapno stw r12, 8(r11) stw r2,_TRAP(r11) SAVE_GPR(0, r11) diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl index f744eb5cba88..96b2157f0371 100644 --- a/arch/powerpc/kernel/syscalls/syscall.tbl +++ b/arch/powerpc/kernel/syscalls/syscall.tbl @@ -9,9 +9,7 @@ # 0 nospu restart_syscall sys_restart_syscall 1 nospu exit sys_exit -2 32 fork ppc_fork sys_fork -2 64 fork sys_fork -2 spu fork sys_ni_syscall +2 nospu fork sys_fork 3 common read sys_read 4 common write sys_write 5 common open sys_open compat_sys_open @@ -160,9 +158,7 @@ 119 32 sigreturn sys_sigreturn compat_sys_sigreturn 119 64 sigreturn sys_ni_syscall 119 spu sigreturn sys_ni_syscall -120 32 clone ppc_clone sys_clone -120 64 clone sys_clone -120 spu clone sys_ni_syscall +120 nospu clone sys_clone 121 common setdomainname sys_setdomainname 122 common uname sys_newuname 123 common modify_ldt sys_ni_syscall @@ -244,9 +240,7 @@ 186 spu sendfile sys_sendfile64 187 common getpmsg sys_ni_syscall 188 common putpmsg sys_ni_syscall -189 32 vfork ppc_vfork sys_vfork -189 64 vfork sys_vfork -189 spu vfork sys_ni_syscall +189 nospu vfork sys_vfork 190 common ugetrlimit sys_getrlimit compat_sys_getrlimit 191 common readahead sys_readahead compat_sys_readahead 192 32 mmap2 sys_mmap2 compat_sys_mmap2 @@ -322,9 +316,7 @@ 248 32 clock_nanosleep sys_clock_nanosleep_time32 248 64 clock_nanosleep sys_clock_nanosleep 248 spu clock_nanosleep sys_clock_nanosleep -249 32 swapcontext ppc_swapcontext compat_sys_swapcontext -249 64 swapcontext sys_swapcontext -249 spu swapcontext sys_ni_syscall +249 nospu swapcontext sys_swapcontext compat_sys_swapcontext 250 common tgkill sys_tgkill 251 32 utimes sys_utimes_time32 251 64 utimes sys_utimes @@ -522,9 +514,7 @@ 432 common fsmount sys_fsmount 433 common fspick sys_fspick 434 common pidfd_open sys_pidfd_open -435 32 clone3 ppc_clone3 sys_clone3 -435 64 clone3 sys_clone3 -435 spu clone3 sys_ni_syscall +435 nospu clone3 sys_clone3 436 common close_range sys_close_range 437 common openat2 sys_openat2 438 common pidfd_getfd sys_pidfd_getfd -- 2.25.0