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89b3098703
Current arch_cpu_idle() is called with IRQs disabled, but will return with IRQs enabled. However, the very first thing the generic code does after calling arch_cpu_idle() is raw_local_irq_disable(). This means that architectures that can idle with IRQs disabled end up doing a pointless 'enable-disable' dance. Therefore, push this IRQ disabling into the idle function, meaning that those architectures can avoid the pointless IRQ state flipping. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64] Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Guo Ren <guoren@kernel.org> Acked-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20230112195540.618076436@infradead.org
104 lines
2.4 KiB
C
104 lines
2.4 KiB
C
// SPDX-License-Identifier: GPL-2.0
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// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
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#include <linux/module.h>
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#include <linux/sched.h>
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#include <linux/sched/task_stack.h>
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#include <linux/sched/debug.h>
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#include <linux/delay.h>
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#include <linux/kallsyms.h>
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#include <linux/uaccess.h>
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#include <linux/ptrace.h>
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#include <linux/elfcore.h>
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#include <asm/elf.h>
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#include <abi/reg_ops.h>
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struct cpuinfo_csky cpu_data[NR_CPUS];
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#ifdef CONFIG_STACKPROTECTOR
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#include <linux/stackprotector.h>
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unsigned long __stack_chk_guard __read_mostly;
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EXPORT_SYMBOL(__stack_chk_guard);
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#endif
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asmlinkage void ret_from_fork(void);
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asmlinkage void ret_from_kernel_thread(void);
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/*
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* Some archs flush debug and FPU info here
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*/
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void flush_thread(void){}
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int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
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{
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unsigned long clone_flags = args->flags;
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unsigned long usp = args->stack;
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unsigned long tls = args->tls;
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struct switch_stack *childstack;
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struct pt_regs *childregs = task_pt_regs(p);
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#ifdef CONFIG_CPU_HAS_FPU
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save_to_user_fp(&p->thread.user_fp);
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#endif
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childstack = ((struct switch_stack *) childregs) - 1;
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memset(childstack, 0, sizeof(struct switch_stack));
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/* setup thread.sp for switch_to !!! */
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p->thread.sp = (unsigned long)childstack;
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if (unlikely(args->fn)) {
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memset(childregs, 0, sizeof(struct pt_regs));
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childstack->r15 = (unsigned long) ret_from_kernel_thread;
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childstack->r10 = (unsigned long) args->fn_arg;
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childstack->r9 = (unsigned long) args->fn;
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childregs->sr = mfcr("psr");
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} else {
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*childregs = *(current_pt_regs());
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if (usp)
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childregs->usp = usp;
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if (clone_flags & CLONE_SETTLS)
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task_thread_info(p)->tp_value = childregs->tls
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= tls;
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childregs->a0 = 0;
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childstack->r15 = (unsigned long) ret_from_fork;
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}
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return 0;
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}
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/* Fill in the fpu structure for a core dump. */
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int elf_core_copy_task_fpregs(struct task_struct *t, elf_fpregset_t *fpu)
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{
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memcpy(fpu, ¤t->thread.user_fp, sizeof(*fpu));
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return 1;
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}
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int dump_task_regs(struct task_struct *tsk, elf_gregset_t *pr_regs)
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{
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struct pt_regs *regs = task_pt_regs(tsk);
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/* NOTE: usp is error value. */
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ELF_CORE_COPY_REGS((*pr_regs), regs)
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return 1;
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}
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#ifndef CONFIG_CPU_PM_NONE
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void arch_cpu_idle(void)
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{
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#ifdef CONFIG_CPU_PM_WAIT
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asm volatile("wait\n");
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#endif
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#ifdef CONFIG_CPU_PM_DOZE
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asm volatile("doze\n");
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#endif
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#ifdef CONFIG_CPU_PM_STOP
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asm volatile("stop\n");
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#endif
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}
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#endif
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