From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934280AbbI1PSV (ORCPT ); Mon, 28 Sep 2015 11:18:21 -0400 Received: from mail-db3on0075.outbound.protection.outlook.com ([157.55.234.75]:42010 "EHLO emea01-db3-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S934264AbbI1PSO (ORCPT ); Mon, 28 Sep 2015 11:18:14 -0400 Authentication-Results: spf=fail (sender IP is 12.216.194.146) smtp.mailfrom=ezchip.com; ezchip.com; dkim=none (message not signed) header.d=none;ezchip.com; dmarc=none action=none header.from=ezchip.com; From: Chris Metcalf To: Gilad Ben Yossef , Steven Rostedt , Ingo Molnar , Peter Zijlstra , Andrew Morton , "Rik van Riel" , Tejun Heo , Frederic Weisbecker , Thomas Gleixner , "Paul E. McKenney" , Christoph Lameter , Viresh Kumar , Catalin Marinas , Will Deacon , Andy Lutomirski , , CC: Chris Metcalf Subject: [PATCH v7 08/11] arch/arm64: adopt prepare_exit_to_usermode() model from x86 Date: Mon, 28 Sep 2015 11:17:23 -0400 Message-ID: <1443453446-7827-9-git-send-email-cmetcalf@ezchip.com> X-Mailer: git-send-email 2.1.2 In-Reply-To: <1443453446-7827-1-git-send-email-cmetcalf@ezchip.com> References: <1443453446-7827-1-git-send-email-cmetcalf@ezchip.com> X-EOPAttributedMessage: 0 X-Microsoft-Exchange-Diagnostics: 1;DB3FFO11FD023;1:Hp6pZA2GeLB29srbBkQlpogzuQklQ1yHLx6EwTvIbRT5+WrYK4pJtTWHwrBvyZj4qRhLcTVytOTIVDx910akh8I1hSDk87JJEYkhgeWGxv3KxmEOk66G/dZLr/RB2MpAKFtMU6k9D+BFQaV8vXXFtvbay7E2xgC1xqUOKw7iCPb8yCyx6OPaA82tvmsDiOPdkiaNGj5j79pqoO9rPrVz3MD79nsaP53d7GSygpk7SX0bC0NL8ZHwstgK2wxsQgPmMpyfg6eKfdKzHVpU4jEVPpdMu2XThkrbE3HfoLxlMEyqTLdYOQf+MCmwwESxl96rSQHoNoqfDe2kFrL32yNk7BV4eqcuH7ftGEj4YAzskxU= X-Forefront-Antispam-Report: CIP:12.216.194.146;CTRY:US;IPV:NLI;EFV:NLI;SFV:NSPM;SFS:(10009020)(6009001)(2980300002)(1109001)(1110001)(339900001)(199003)(189002)(107886002)(2201001)(47776003)(189998001)(97736004)(68736005)(2950100001)(5001960100002)(5007970100001)(5001770100001)(77156002)(4001540100001)(81156007)(62966003)(5001860100001)(85426001)(50226001)(5003940100001)(92566002)(5001830100001)(229853001)(11100500001)(86362001)(42186005)(87936001)(64706001)(19580405001)(46102003)(106356001)(106466001)(50986999)(106476002)(105606002)(104016004)(6806005)(19580395003)(76176999)(50466002)(33646002)(36756003)(48376002)(9376005)(921003)(83996005)(1121003)(4001430100001)(2101003);DIR:OUT;SFP:1101;SCL:1;SRVR:VI1PR02MB0784;H:ld-1.internal.tilera.com;FPR:;SPF:Fail;PTR:InfoNoRecords;A:1;MX:1;LANG:en; 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The existing arm64 do_notify_resume() is called in a loop from assembly on the slow path; this change moves the loop into C code as well. For the x86 version see commit c5c46f59e4e7 ("x86/entry: Add new, comprehensible entry and exit handlers written in C"). Signed-off-by: Chris Metcalf --- arch/arm64/kernel/entry.S | 6 +++--- arch/arm64/kernel/signal.c | 32 ++++++++++++++++++++++---------- 2 files changed, 25 insertions(+), 13 deletions(-) diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index 4306c937b1ff..6fcbf8ea307b 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -628,9 +628,8 @@ work_pending: mov x0, sp // 'regs' tst x2, #PSR_MODE_MASK // user mode regs? b.ne no_work_pending // returning to kernel - enable_irq // enable interrupts for do_notify_resume() - bl do_notify_resume - b ret_to_user + bl prepare_exit_to_usermode + b no_user_work_pending work_resched: bl schedule @@ -642,6 +641,7 @@ ret_to_user: ldr x1, [tsk, #TI_FLAGS] and x2, x1, #_TIF_WORK_MASK cbnz x2, work_pending +no_user_work_pending: enable_step_tsk x1, x2 no_work_pending: kernel_exit 0 diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c index e18c48cb6db1..fde59c1139a9 100644 --- a/arch/arm64/kernel/signal.c +++ b/arch/arm64/kernel/signal.c @@ -399,18 +399,30 @@ static void do_signal(struct pt_regs *regs) restore_saved_sigmask(); } -asmlinkage void do_notify_resume(struct pt_regs *regs, - unsigned int thread_flags) +asmlinkage void prepare_exit_to_usermode(struct pt_regs *regs, + unsigned int thread_flags) { - if (thread_flags & _TIF_SIGPENDING) - do_signal(regs); + do { + local_irq_enable(); - if (thread_flags & _TIF_NOTIFY_RESUME) { - clear_thread_flag(TIF_NOTIFY_RESUME); - tracehook_notify_resume(regs); - } + if (thread_flags & _TIF_NEED_RESCHED) + schedule(); + + if (thread_flags & _TIF_SIGPENDING) + do_signal(regs); + + if (thread_flags & _TIF_NOTIFY_RESUME) { + clear_thread_flag(TIF_NOTIFY_RESUME); + tracehook_notify_resume(regs); + } + + if (thread_flags & _TIF_FOREIGN_FPSTATE) + fpsimd_restore_current_state(); + + local_irq_disable(); - if (thread_flags & _TIF_FOREIGN_FPSTATE) - fpsimd_restore_current_state(); + thread_flags = READ_ONCE(current_thread_info()->flags) & + _TIF_WORK_MASK; + } while (thread_flags); } -- 2.1.2