From patchwork Thu Oct 22 22:26:58 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ira Weiny X-Patchwork-Id: 11852059 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 423796A2 for ; Thu, 22 Oct 2020 22:27:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1AD692245F for ; Thu, 22 Oct 2020 22:27:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S372843AbgJVW10 (ORCPT ); Thu, 22 Oct 2020 18:27:26 -0400 Received: from mga09.intel.com ([134.134.136.24]:58289 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S372834AbgJVW1Y (ORCPT ); Thu, 22 Oct 2020 18:27:24 -0400 IronPort-SDR: ZGtgRLIlXnqHniem+MDjHELet4eemU8D2pe5NtrEpeTTUvveRsXF5cUp8Nqjd+2Pz40/mEsHgC 686JqyWPEdrw== X-IronPort-AV: E=McAfee;i="6000,8403,9782"; a="167725394" X-IronPort-AV: E=Sophos;i="5.77,404,1596524400"; d="scan'208";a="167725394" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Oct 2020 15:27:22 -0700 IronPort-SDR: xAWWtR61Wd7ivlq9hw6NniD5y+APhtv76bIa8gagYa6pcHiUUQwJVfdJu/qfciWTD0n4VPfsex JIBqPbGpIE2A== X-IronPort-AV: E=Sophos;i="5.77,404,1596524400"; d="scan'208";a="359408080" Received: from iweiny-desk2.sc.intel.com (HELO localhost) ([10.3.52.147]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Oct 2020 15:27:22 -0700 From: ira.weiny@intel.com To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Andy Lutomirski , Peter Zijlstra Cc: Ira Weiny , x86@kernel.org, Dave Hansen , Dan Williams , Andrew Morton , Fenghua Yu , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-nvdimm@lists.01.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org Subject: [PATCH 07/10] x86/entry: Pass irqentry_state_t by reference Date: Thu, 22 Oct 2020 15:26:58 -0700 Message-Id: <20201022222701.887660-8-ira.weiny@intel.com> X-Mailer: git-send-email 2.28.0.rc0.12.gb6a658bd00c9 In-Reply-To: <20201022222701.887660-1-ira.weiny@intel.com> References: <20201022222701.887660-1-ira.weiny@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org From: Ira Weiny In preparation for adding PKS information to struct irqentry_state_t change all call sites and usages to pass the struct by reference instead of by value. While we are editing the call sites it is a good time to standardize on the name 'irq_state'. Signed-off-by: Ira Weiny --- Changes from RFC V3 Clean up @irq_state comments Standardize on 'irq_state' for the state variable name Refactor based on new patch from Thomas Gleixner Also addresses Peter Zijlstra's comment --- arch/x86/entry/common.c | 8 ++++---- arch/x86/include/asm/idtentry.h | 25 ++++++++++++++---------- arch/x86/kernel/cpu/mce/core.c | 4 ++-- arch/x86/kernel/kvm.c | 6 +++--- arch/x86/kernel/nmi.c | 4 ++-- arch/x86/kernel/traps.c | 21 ++++++++++++-------- arch/x86/mm/fault.c | 6 +++--- include/linux/entry-common.h | 16 ++++++++++------ kernel/entry/common.c | 34 +++++++++++++-------------------- 9 files changed, 65 insertions(+), 59 deletions(-) diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index 18d8f17f755c..87dea56a15d2 100644 --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -259,9 +259,9 @@ __visible noinstr void xen_pv_evtchn_do_upcall(struct pt_regs *regs) { struct pt_regs *old_regs; bool inhcall; - irqentry_state_t state; + irqentry_state_t irq_state; - state = irqentry_enter(regs); + irqentry_enter(regs, &irq_state); old_regs = set_irq_regs(regs); instrumentation_begin(); @@ -271,13 +271,13 @@ __visible noinstr void xen_pv_evtchn_do_upcall(struct pt_regs *regs) set_irq_regs(old_regs); inhcall = get_and_clear_inhcall(); - if (inhcall && !WARN_ON_ONCE(state.exit_rcu)) { + if (inhcall && !WARN_ON_ONCE(irq_state.exit_rcu)) { instrumentation_begin(); irqentry_exit_cond_resched(); instrumentation_end(); restore_inhcall(inhcall); } else { - irqentry_exit(regs, state); + irqentry_exit(regs, &irq_state); } } #endif /* CONFIG_XEN_PV */ diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h index 247a60a47331..282d2413b6a1 100644 --- a/arch/x86/include/asm/idtentry.h +++ b/arch/x86/include/asm/idtentry.h @@ -49,12 +49,13 @@ static __always_inline void __##func(struct pt_regs *regs); \ \ __visible noinstr void func(struct pt_regs *regs) \ { \ - irqentry_state_t state = irqentry_enter(regs); \ + irqentry_state_t irq_state; \ \ + irqentry_enter(regs, &irq_state); \ instrumentation_begin(); \ __##func (regs); \ instrumentation_end(); \ - irqentry_exit(regs, state); \ + irqentry_exit(regs, &irq_state); \ } \ \ static __always_inline void __##func(struct pt_regs *regs) @@ -96,12 +97,13 @@ static __always_inline void __##func(struct pt_regs *regs, \ __visible noinstr void func(struct pt_regs *regs, \ unsigned long error_code) \ { \ - irqentry_state_t state = irqentry_enter(regs); \ + irqentry_state_t irq_state; \ \ + irqentry_enter(regs, &irq_state); \ instrumentation_begin(); \ __##func (regs, error_code); \ instrumentation_end(); \ - irqentry_exit(regs, state); \ + irqentry_exit(regs, &irq_state); \ } \ \ static __always_inline void __##func(struct pt_regs *regs, \ @@ -192,15 +194,16 @@ static __always_inline void __##func(struct pt_regs *regs, u8 vector); \ __visible noinstr void func(struct pt_regs *regs, \ unsigned long error_code) \ { \ - irqentry_state_t state = irqentry_enter(regs); \ + irqentry_state_t irq_state; \ \ + irqentry_enter(regs, &irq_state); \ instrumentation_begin(); \ irq_enter_rcu(); \ kvm_set_cpu_l1tf_flush_l1d(); \ __##func (regs, (u8)error_code); \ irq_exit_rcu(); \ instrumentation_end(); \ - irqentry_exit(regs, state); \ + irqentry_exit(regs, &irq_state); \ } \ \ static __always_inline void __##func(struct pt_regs *regs, u8 vector) @@ -234,15 +237,16 @@ static void __##func(struct pt_regs *regs); \ \ __visible noinstr void func(struct pt_regs *regs) \ { \ - irqentry_state_t state = irqentry_enter(regs); \ + irqentry_state_t irq_state; \ \ + irqentry_enter(regs, &irq_state); \ instrumentation_begin(); \ irq_enter_rcu(); \ kvm_set_cpu_l1tf_flush_l1d(); \ run_sysvec_on_irqstack_cond(__##func, regs); \ irq_exit_rcu(); \ instrumentation_end(); \ - irqentry_exit(regs, state); \ + irqentry_exit(regs, &irq_state); \ } \ \ static noinline void __##func(struct pt_regs *regs) @@ -263,15 +267,16 @@ static __always_inline void __##func(struct pt_regs *regs); \ \ __visible noinstr void func(struct pt_regs *regs) \ { \ - irqentry_state_t state = irqentry_enter(regs); \ + irqentry_state_t irq_state; \ \ + irqentry_enter(regs, &irq_state); \ instrumentation_begin(); \ __irq_enter_raw(); \ kvm_set_cpu_l1tf_flush_l1d(); \ __##func (regs); \ __irq_exit_raw(); \ instrumentation_end(); \ - irqentry_exit(regs, state); \ + irqentry_exit(regs, &irq_state); \ } \ \ static __always_inline void __##func(struct pt_regs *regs) diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c index eb3338c0bbc1..f90f2163e366 100644 --- a/arch/x86/kernel/cpu/mce/core.c +++ b/arch/x86/kernel/cpu/mce/core.c @@ -1995,7 +1995,7 @@ static __always_inline void exc_machine_check_kernel(struct pt_regs *regs) mce_check_crashing_cpu()) return; - irq_state = irqentry_nmi_enter(regs); + irqentry_nmi_enter(regs, &irq_state); /* * The call targets are marked noinstr, but objtool can't figure * that out because it's an indirect call. Annotate it. @@ -2006,7 +2006,7 @@ static __always_inline void exc_machine_check_kernel(struct pt_regs *regs) if (regs->flags & X86_EFLAGS_IF) trace_hardirqs_on_prepare(); instrumentation_end(); - irqentry_nmi_exit(regs, irq_state); + irqentry_nmi_exit(regs, &irq_state); } static __always_inline void exc_machine_check_user(struct pt_regs *regs) diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 1c0f2560a41c..78416af3d3a0 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -238,12 +238,12 @@ EXPORT_SYMBOL_GPL(kvm_read_and_reset_apf_flags); noinstr bool __kvm_handle_async_pf(struct pt_regs *regs, u32 token) { u32 flags = kvm_read_and_reset_apf_flags(); - irqentry_state_t state; + irqentry_state_t irq_state; if (!flags) return false; - state = irqentry_enter(regs); + irqentry_enter(regs, &irq_state); instrumentation_begin(); /* @@ -264,7 +264,7 @@ noinstr bool __kvm_handle_async_pf(struct pt_regs *regs, u32 token) } instrumentation_end(); - irqentry_exit(regs, state); + irqentry_exit(regs, &irq_state); return true; } diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c index bf250a339655..1fd7780e99dd 100644 --- a/arch/x86/kernel/nmi.c +++ b/arch/x86/kernel/nmi.c @@ -502,14 +502,14 @@ DEFINE_IDTENTRY_RAW(exc_nmi) this_cpu_write(nmi_dr7, local_db_save()); - irq_state = irqentry_nmi_enter(regs); + irqentry_nmi_enter(regs, &irq_state); inc_irq_stat(__nmi_count); if (!ignore_nmis) default_do_nmi(regs); - irqentry_nmi_exit(regs, irq_state); + irqentry_nmi_exit(regs, &irq_state); local_db_restore(this_cpu_read(nmi_dr7)); diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index bffbbe29fc8c..5566a0a38f63 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -245,7 +245,7 @@ static noinstr bool handle_bug(struct pt_regs *regs) DEFINE_IDTENTRY_RAW(exc_invalid_op) { - irqentry_state_t state; + irqentry_state_t irq_state; /* * We use UD2 as a short encoding for 'CALL __WARN', as such @@ -255,11 +255,11 @@ DEFINE_IDTENTRY_RAW(exc_invalid_op) if (!user_mode(regs) && handle_bug(regs)) return; - state = irqentry_enter(regs); + irqentry_enter(regs, &irq_state); instrumentation_begin(); handle_invalid_op(regs); instrumentation_end(); - irqentry_exit(regs, state); + irqentry_exit(regs, &irq_state); } DEFINE_IDTENTRY(exc_coproc_segment_overrun) @@ -343,6 +343,7 @@ __visible void __noreturn handle_stack_overflow(const char *message, */ DEFINE_IDTENTRY_DF(exc_double_fault) { + irqentry_state_t irq_state; static const char str[] = "double fault"; struct task_struct *tsk = current; @@ -405,7 +406,7 @@ DEFINE_IDTENTRY_DF(exc_double_fault) } #endif - irqentry_nmi_enter(regs); + irqentry_nmi_enter(regs, &irq_state); instrumentation_begin(); notify_die(DIE_TRAP, str, regs, error_code, X86_TRAP_DF, SIGSEGV); @@ -651,13 +652,15 @@ DEFINE_IDTENTRY_RAW(exc_int3) instrumentation_end(); irqentry_exit_to_user_mode(regs); } else { - irqentry_state_t irq_state = irqentry_nmi_enter(regs); + irqentry_state_t irq_state; + + irqentry_nmi_enter(regs, &irq_state); instrumentation_begin(); if (!do_int3(regs)) die("int3", regs, 0); instrumentation_end(); - irqentry_nmi_exit(regs, irq_state); + irqentry_nmi_exit(regs, &irq_state); } } @@ -865,7 +868,9 @@ static __always_inline void exc_debug_kernel(struct pt_regs *regs, * includes the entry stack is excluded for everything. */ unsigned long dr7 = local_db_save(); - irqentry_state_t irq_state = irqentry_nmi_enter(regs); + irqentry_state_t irq_state; + + irqentry_nmi_enter(regs, &irq_state); instrumentation_begin(); /* @@ -908,7 +913,7 @@ static __always_inline void exc_debug_kernel(struct pt_regs *regs, regs->flags &= ~X86_EFLAGS_TF; out: instrumentation_end(); - irqentry_nmi_exit(regs, irq_state); + irqentry_nmi_exit(regs, &irq_state); local_db_restore(dr7); } diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 42606a04ae85..5e3fd7763315 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -1441,7 +1441,7 @@ handle_page_fault(struct pt_regs *regs, unsigned long error_code, DEFINE_IDTENTRY_RAW_ERRORCODE(exc_page_fault) { unsigned long address = read_cr2(); - irqentry_state_t state; + irqentry_state_t irq_state; prefetchw(¤t->mm->mmap_lock); @@ -1476,11 +1476,11 @@ DEFINE_IDTENTRY_RAW_ERRORCODE(exc_page_fault) * code reenabled RCU to avoid subsequent wreckage which helps * debugability. */ - state = irqentry_enter(regs); + irqentry_enter(regs, &irq_state); instrumentation_begin(); handle_page_fault(regs, error_code, address); instrumentation_end(); - irqentry_exit(regs, state); + irqentry_exit(regs, &irq_state); } diff --git a/include/linux/entry-common.h b/include/linux/entry-common.h index 47f9a0658acf..b79704af744f 100644 --- a/include/linux/entry-common.h +++ b/include/linux/entry-common.h @@ -352,6 +352,8 @@ typedef struct irqentry_state { /** * irqentry_enter - Handle state tracking on ordinary interrupt entries * @regs: Pointer to pt_regs of interrupted context + * @irq_state: Pointer to state information; to be passed back to + * irqentry_exit() * * Invokes: * - lockdep irqflag state tracking as low level ASM entry disabled @@ -380,7 +382,7 @@ typedef struct irqentry_state { * * Returns: An opaque object that must be passed to idtentry_exit() */ -irqentry_state_t noinstr irqentry_enter(struct pt_regs *regs); +void noinstr irqentry_enter(struct pt_regs *regs, irqentry_state_t *irq_state); /** * irqentry_exit_cond_resched - Conditionally reschedule on return from interrupt @@ -392,7 +394,7 @@ void irqentry_exit_cond_resched(void); /** * irqentry_exit - Handle return from exception that used irqentry_enter() * @regs: Pointer to pt_regs (exception entry regs) - * @state: Return value from matching call to irqentry_enter() + * @irq_state: Pointer to state information passed to irqentry_enter() * * Depending on the return target (kernel/user) this runs the necessary * preemption and work checks if possible and reguired and returns to @@ -403,25 +405,27 @@ void irqentry_exit_cond_resched(void); * * Counterpart to irqentry_enter(). */ -void noinstr irqentry_exit(struct pt_regs *regs, irqentry_state_t state); +void noinstr irqentry_exit(struct pt_regs *regs, irqentry_state_t *irq_state); /** * irqentry_nmi_enter - Handle NMI entry * @regs: Pointer to currents pt_regs + * @irq_state: Pointer to state information; to be passed back to + * irqentry_nmi_exit() * * Similar to irqentry_enter() but taking care of the NMI constraints. */ -irqentry_state_t noinstr irqentry_nmi_enter(struct pt_regs *regs); +void noinstr irqentry_nmi_enter(struct pt_regs *regs, irqentry_state_t *irq_state); /** * irqentry_nmi_exit - Handle return from NMI handling * @regs: Pointer to pt_regs (NMI entry regs) - * @irq_state: Return value from matching call to irqentry_nmi_enter() + * @irq_state: Pointer to state information passed to irqentry_nmi_enter() * * Last action before returning to the low level assmenbly code. * * Counterpart to irqentry_nmi_enter(). */ -void noinstr irqentry_nmi_exit(struct pt_regs *regs, irqentry_state_t irq_state); +void noinstr irqentry_nmi_exit(struct pt_regs *regs, irqentry_state_t *irq_state); #endif diff --git a/kernel/entry/common.c b/kernel/entry/common.c index 5cc2e4174d7c..e4f745b3a229 100644 --- a/kernel/entry/common.c +++ b/kernel/entry/common.c @@ -282,15 +282,13 @@ noinstr void irqentry_exit_to_user_mode(struct pt_regs *regs) exit_to_user_mode(); } -noinstr irqentry_state_t irqentry_enter(struct pt_regs *regs) +noinstr void irqentry_enter(struct pt_regs *regs, irqentry_state_t *irq_state) { - irqentry_state_t ret = { - .exit_rcu = false, - }; + irq_state->exit_rcu = false; if (user_mode(regs)) { irqentry_enter_from_user_mode(regs); - return ret; + return; } /* @@ -328,8 +326,8 @@ noinstr irqentry_state_t irqentry_enter(struct pt_regs *regs) trace_hardirqs_off_finish(); instrumentation_end(); - ret.exit_rcu = true; - return ret; + irq_state->exit_rcu = true; + return; } /* @@ -343,8 +341,6 @@ noinstr irqentry_state_t irqentry_enter(struct pt_regs *regs) /* Use the combo lockdep/tracing function */ trace_hardirqs_off(); instrumentation_end(); - - return ret; } void irqentry_exit_cond_resched(void) @@ -359,7 +355,7 @@ void irqentry_exit_cond_resched(void) } } -noinstr void irqentry_exit(struct pt_regs *regs, irqentry_state_t state) +noinstr void irqentry_exit(struct pt_regs *regs, irqentry_state_t *irq_state) { lockdep_assert_irqs_disabled(); @@ -372,7 +368,7 @@ noinstr void irqentry_exit(struct pt_regs *regs, irqentry_state_t state) * carefully and needs the same ordering of lockdep/tracing * and RCU as the return to user mode path. */ - if (state.exit_rcu) { + if (irq_state->exit_rcu) { instrumentation_begin(); /* Tell the tracer that IRET will enable interrupts */ trace_hardirqs_on_prepare(); @@ -394,16 +390,14 @@ noinstr void irqentry_exit(struct pt_regs *regs, irqentry_state_t state) * IRQ flags state is correct already. Just tell RCU if it * was not watching on entry. */ - if (state.exit_rcu) + if (irq_state->exit_rcu) rcu_irq_exit(); } } -irqentry_state_t noinstr irqentry_nmi_enter(struct pt_regs *regs) +void noinstr irqentry_nmi_enter(struct pt_regs *regs, irqentry_state_t *irq_state) { - irqentry_state_t irq_state; - - irq_state.lockdep = lockdep_hardirqs_enabled(); + irq_state->lockdep = lockdep_hardirqs_enabled(); __nmi_enter(); lockdep_hardirqs_off(CALLER_ADDR0); @@ -414,15 +408,13 @@ irqentry_state_t noinstr irqentry_nmi_enter(struct pt_regs *regs) trace_hardirqs_off_finish(); ftrace_nmi_enter(); instrumentation_end(); - - return irq_state; } -void noinstr irqentry_nmi_exit(struct pt_regs *regs, irqentry_state_t irq_state) +void noinstr irqentry_nmi_exit(struct pt_regs *regs, irqentry_state_t *irq_state) { instrumentation_begin(); ftrace_nmi_exit(); - if (irq_state.lockdep) { + if (irq_state->lockdep) { trace_hardirqs_on_prepare(); lockdep_hardirqs_on_prepare(CALLER_ADDR0); } @@ -430,7 +422,7 @@ void noinstr irqentry_nmi_exit(struct pt_regs *regs, irqentry_state_t irq_state) rcu_nmi_exit(); lockdep_hardirq_exit(); - if (irq_state.lockdep) + if (irq_state->lockdep) lockdep_hardirqs_on(CALLER_ADDR0); __nmi_exit(); }