![Li Zhong](/assets/img/avatar_default.png)
There are a few tracepoints in the interrupt code path, which is before irq_enter(), or after irq_exit(), like trace_irq_entry()/trace_irq_exit() in do_IRQ(), trace_timer_interrupt_entry()/trace_timer_interrupt_exit() in timer_interrupt(). If the interrupt is from idle(), and because tracepoint contains RCU read-side critical section, we could see following suspicious RCU usage reported: [ 145.127743] =============================== [ 145.127747] [ INFO: suspicious RCU usage. ] [ 145.127752] 3.6.0-rc3+ #1 Not tainted [ 145.127755] ------------------------------- [ 145.127759] /root/.workdir/linux/arch/powerpc/include/asm/trace.h:33 suspicious rcu_dereference_check() usage! [ 145.127765] [ 145.127765] other info that might help us debug this: [ 145.127765] [ 145.127771] [ 145.127771] RCU used illegally from idle CPU! [ 145.127771] rcu_scheduler_active = 1, debug_locks = 0 [ 145.127777] RCU used illegally from extended quiescent state! [ 145.127781] no locks held by swapper/0/0. [ 145.127785] [ 145.127785] stack backtrace: [ 145.127789] Call Trace: [ 145.127796] [c00000000108b530] [c000000000013c40] .show_stack +0x70/0x1c0 (unreliable) [ 145.127806] [c00000000108b5e0] [c0000000000f59d8] .lockdep_rcu_suspicious+0x118/0x150 [ 145.127813] [c00000000108b680] [c00000000000fc58] .do_IRQ+0x498/0x500 [ 145.127820] [c00000000108b750] [c000000000003950] hardware_interrupt_common+0x150/0x180 [ 145.127828] --- Exception: 501 at .plpar_hcall_norets+0x84/0xd4 [ 145.127828] LR = .check_and_cede_processor+0x38/0x70 [ 145.127836] [c00000000108bab0] [c0000000000665dc] .shared_cede_loop +0x5c/0x100 [ 145.127844] [c00000000108bb70] [c000000000588ab0] .cpuidle_enter +0x30/0x50 [ 145.127850] [c00000000108bbe0] [c000000000588b0c] .cpuidle_enter_state+0x3c/0xb0 [ 145.127857] [c00000000108bc60] [c000000000589730] .cpuidle_idle_call +0x150/0x6c0 [ 145.127863] [c00000000108bd30] [c000000000058440] .pSeries_idle +0x10/0x40 [ 145.127870] [c00000000108bda0] [c00000000001683c] .cpu_idle +0x18c/0x2d0 [ 145.127876] [c00000000108be60] [c00000000000b434] .rest_init +0x124/0x1b0 [ 145.127884] [c00000000108bef0] [c0000000009d0d28] .start_kernel +0x568/0x588 [ 145.127890] [c00000000108bf90] [c000000000009660] .start_here_common +0x20/0x40 This is because the RCU usage in interrupt context should be used in area marked by rcu_irq_enter()/rcu_irq_exit(), called in irq_enter()/irq_exit() respectively. Move them into the irq_enter()/irq_exit() area to avoid the reporting. Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
681 lines
17 KiB
C
681 lines
17 KiB
C
/*
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* Derived from arch/i386/kernel/irq.c
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* Copyright (C) 1992 Linus Torvalds
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* Adapted from arch/i386 by Gary Thomas
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* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
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* Updated and modified by Cort Dougan <cort@fsmlabs.com>
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* Copyright (C) 1996-2001 Cort Dougan
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* Adapted for Power Macintosh by Paul Mackerras
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* Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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* This file contains the code used by various IRQ handling routines:
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* asking for different IRQ's should be done through these routines
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* instead of just grabbing them. Thus setups with different IRQ numbers
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* shouldn't result in any weird surprises, and installing new handlers
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* should be easier.
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*
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* The MPC8xx has an interrupt mask in the SIU. If a bit is set, the
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* interrupt is _enabled_. As expected, IRQ0 is bit 0 in the 32-bit
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* mask register (of which only 16 are defined), hence the weird shifting
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* and complement of the cached_irq_mask. I want to be able to stuff
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* this right into the SIU SMASK register.
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* Many of the prep/chrp functions are conditional compiled on CONFIG_8xx
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* to reduce code space and undefined function references.
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*/
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#undef DEBUG
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#include <linux/export.h>
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#include <linux/threads.h>
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#include <linux/kernel_stat.h>
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#include <linux/signal.h>
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#include <linux/sched.h>
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#include <linux/ptrace.h>
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#include <linux/ioport.h>
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#include <linux/interrupt.h>
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#include <linux/timex.h>
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#include <linux/init.h>
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#include <linux/slab.h>
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#include <linux/delay.h>
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#include <linux/irq.h>
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#include <linux/seq_file.h>
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#include <linux/cpumask.h>
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#include <linux/profile.h>
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#include <linux/bitops.h>
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#include <linux/list.h>
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#include <linux/radix-tree.h>
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#include <linux/mutex.h>
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#include <linux/bootmem.h>
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#include <linux/pci.h>
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#include <linux/debugfs.h>
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#include <linux/of.h>
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#include <linux/of_irq.h>
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#include <asm/uaccess.h>
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#include <asm/io.h>
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#include <asm/pgtable.h>
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#include <asm/irq.h>
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#include <asm/cache.h>
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#include <asm/prom.h>
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#include <asm/ptrace.h>
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#include <asm/machdep.h>
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#include <asm/udbg.h>
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#include <asm/smp.h>
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#include <asm/debug.h>
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#ifdef CONFIG_PPC64
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#include <asm/paca.h>
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#include <asm/firmware.h>
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#include <asm/lv1call.h>
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#endif
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#define CREATE_TRACE_POINTS
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#include <asm/trace.h>
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DEFINE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
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EXPORT_PER_CPU_SYMBOL(irq_stat);
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int __irq_offset_value;
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#ifdef CONFIG_PPC32
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EXPORT_SYMBOL(__irq_offset_value);
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atomic_t ppc_n_lost_interrupts;
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#ifdef CONFIG_TAU_INT
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extern int tau_initialized;
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extern int tau_interrupts(int);
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#endif
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#endif /* CONFIG_PPC32 */
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#ifdef CONFIG_PPC64
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int distribute_irqs = 1;
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static inline notrace unsigned long get_irq_happened(void)
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{
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unsigned long happened;
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__asm__ __volatile__("lbz %0,%1(13)"
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: "=r" (happened) : "i" (offsetof(struct paca_struct, irq_happened)));
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return happened;
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}
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static inline notrace void set_soft_enabled(unsigned long enable)
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{
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__asm__ __volatile__("stb %0,%1(13)"
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: : "r" (enable), "i" (offsetof(struct paca_struct, soft_enabled)));
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}
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static inline notrace int decrementer_check_overflow(void)
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{
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u64 now = get_tb_or_rtc();
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u64 *next_tb = &__get_cpu_var(decrementers_next_tb);
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if (now >= *next_tb)
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set_dec(1);
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return now >= *next_tb;
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}
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/* This is called whenever we are re-enabling interrupts
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* and returns either 0 (nothing to do) or 500/900 if there's
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* either an EE or a DEC to generate.
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*
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* This is called in two contexts: From arch_local_irq_restore()
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* before soft-enabling interrupts, and from the exception exit
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* path when returning from an interrupt from a soft-disabled to
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* a soft enabled context. In both case we have interrupts hard
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* disabled.
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*
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* We take care of only clearing the bits we handled in the
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* PACA irq_happened field since we can only re-emit one at a
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* time and we don't want to "lose" one.
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*/
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notrace unsigned int __check_irq_replay(void)
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{
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/*
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* We use local_paca rather than get_paca() to avoid all
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* the debug_smp_processor_id() business in this low level
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* function
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*/
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unsigned char happened = local_paca->irq_happened;
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/* Clear bit 0 which we wouldn't clear otherwise */
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local_paca->irq_happened &= ~PACA_IRQ_HARD_DIS;
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/*
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* Force the delivery of pending soft-disabled interrupts on PS3.
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* Any HV call will have this side effect.
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*/
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if (firmware_has_feature(FW_FEATURE_PS3_LV1)) {
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u64 tmp, tmp2;
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lv1_get_version_info(&tmp, &tmp2);
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}
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/*
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* We may have missed a decrementer interrupt. We check the
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* decrementer itself rather than the paca irq_happened field
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* in case we also had a rollover while hard disabled
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*/
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local_paca->irq_happened &= ~PACA_IRQ_DEC;
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if (decrementer_check_overflow())
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return 0x900;
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/* Finally check if an external interrupt happened */
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local_paca->irq_happened &= ~PACA_IRQ_EE;
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if (happened & PACA_IRQ_EE)
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return 0x500;
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#ifdef CONFIG_PPC_BOOK3E
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/* Finally check if an EPR external interrupt happened
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* this bit is typically set if we need to handle another
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* "edge" interrupt from within the MPIC "EPR" handler
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*/
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local_paca->irq_happened &= ~PACA_IRQ_EE_EDGE;
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if (happened & PACA_IRQ_EE_EDGE)
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return 0x500;
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local_paca->irq_happened &= ~PACA_IRQ_DBELL;
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if (happened & PACA_IRQ_DBELL)
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return 0x280;
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#endif /* CONFIG_PPC_BOOK3E */
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/* There should be nothing left ! */
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BUG_ON(local_paca->irq_happened != 0);
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return 0;
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}
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notrace void arch_local_irq_restore(unsigned long en)
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{
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unsigned char irq_happened;
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unsigned int replay;
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/* Write the new soft-enabled value */
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set_soft_enabled(en);
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if (!en)
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return;
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/*
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* From this point onward, we can take interrupts, preempt,
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* etc... unless we got hard-disabled. We check if an event
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* happened. If none happened, we know we can just return.
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*
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* We may have preempted before the check below, in which case
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* we are checking the "new" CPU instead of the old one. This
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* is only a problem if an event happened on the "old" CPU.
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*
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* External interrupt events will have caused interrupts to
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* be hard-disabled, so there is no problem, we
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* cannot have preempted.
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*/
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irq_happened = get_irq_happened();
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if (!irq_happened)
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return;
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/*
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* We need to hard disable to get a trusted value from
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* __check_irq_replay(). We also need to soft-disable
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* again to avoid warnings in there due to the use of
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* per-cpu variables.
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*
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* We know that if the value in irq_happened is exactly 0x01
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* then we are already hard disabled (there are other less
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* common cases that we'll ignore for now), so we skip the
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* (expensive) mtmsrd.
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*/
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if (unlikely(irq_happened != PACA_IRQ_HARD_DIS))
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__hard_irq_disable();
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#ifdef CONFIG_TRACE_IRQFLAGS
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else {
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/*
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* We should already be hard disabled here. We had bugs
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* where that wasn't the case so let's dbl check it and
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* warn if we are wrong. Only do that when IRQ tracing
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* is enabled as mfmsr() can be costly.
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*/
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if (WARN_ON(mfmsr() & MSR_EE))
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__hard_irq_disable();
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}
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#endif /* CONFIG_TRACE_IRQFLAG */
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set_soft_enabled(0);
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/*
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* Check if anything needs to be re-emitted. We haven't
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* soft-enabled yet to avoid warnings in decrementer_check_overflow
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* accessing per-cpu variables
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*/
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replay = __check_irq_replay();
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/* We can soft-enable now */
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set_soft_enabled(1);
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/*
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* And replay if we have to. This will return with interrupts
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* hard-enabled.
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*/
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if (replay) {
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__replay_interrupt(replay);
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return;
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}
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/* Finally, let's ensure we are hard enabled */
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__hard_irq_enable();
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}
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EXPORT_SYMBOL(arch_local_irq_restore);
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/*
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* This is specifically called by assembly code to re-enable interrupts
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* if they are currently disabled. This is typically called before
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* schedule() or do_signal() when returning to userspace. We do it
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* in C to avoid the burden of dealing with lockdep etc...
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*
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* NOTE: This is called with interrupts hard disabled but not marked
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* as such in paca->irq_happened, so we need to resync this.
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*/
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void notrace restore_interrupts(void)
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{
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if (irqs_disabled()) {
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local_paca->irq_happened |= PACA_IRQ_HARD_DIS;
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local_irq_enable();
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} else
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__hard_irq_enable();
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}
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/*
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* This is a helper to use when about to go into idle low-power
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* when the latter has the side effect of re-enabling interrupts
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* (such as calling H_CEDE under pHyp).
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*
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* You call this function with interrupts soft-disabled (this is
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* already the case when ppc_md.power_save is called). The function
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* will return whether to enter power save or just return.
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*
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* In the former case, it will have notified lockdep of interrupts
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* being re-enabled and generally sanitized the lazy irq state,
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* and in the latter case it will leave with interrupts hard
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* disabled and marked as such, so the local_irq_enable() call
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* in cpu_idle() will properly re-enable everything.
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*/
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bool prep_irq_for_idle(void)
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{
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/*
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* First we need to hard disable to ensure no interrupt
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* occurs before we effectively enter the low power state
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*/
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hard_irq_disable();
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/*
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* If anything happened while we were soft-disabled,
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* we return now and do not enter the low power state.
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*/
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if (lazy_irq_pending())
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return false;
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/* Tell lockdep we are about to re-enable */
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trace_hardirqs_on();
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/*
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* Mark interrupts as soft-enabled and clear the
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* PACA_IRQ_HARD_DIS from the pending mask since we
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* are about to hard enable as well as a side effect
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* of entering the low power state.
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*/
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local_paca->irq_happened &= ~PACA_IRQ_HARD_DIS;
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local_paca->soft_enabled = 1;
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/* Tell the caller to enter the low power state */
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return true;
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}
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#endif /* CONFIG_PPC64 */
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int arch_show_interrupts(struct seq_file *p, int prec)
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{
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int j;
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#if defined(CONFIG_PPC32) && defined(CONFIG_TAU_INT)
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if (tau_initialized) {
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seq_printf(p, "%*s: ", prec, "TAU");
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for_each_online_cpu(j)
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seq_printf(p, "%10u ", tau_interrupts(j));
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seq_puts(p, " PowerPC Thermal Assist (cpu temp)\n");
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}
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#endif /* CONFIG_PPC32 && CONFIG_TAU_INT */
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seq_printf(p, "%*s: ", prec, "LOC");
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for_each_online_cpu(j)
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seq_printf(p, "%10u ", per_cpu(irq_stat, j).timer_irqs);
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seq_printf(p, " Local timer interrupts\n");
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seq_printf(p, "%*s: ", prec, "SPU");
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for_each_online_cpu(j)
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seq_printf(p, "%10u ", per_cpu(irq_stat, j).spurious_irqs);
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seq_printf(p, " Spurious interrupts\n");
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seq_printf(p, "%*s: ", prec, "CNT");
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for_each_online_cpu(j)
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seq_printf(p, "%10u ", per_cpu(irq_stat, j).pmu_irqs);
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seq_printf(p, " Performance monitoring interrupts\n");
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seq_printf(p, "%*s: ", prec, "MCE");
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for_each_online_cpu(j)
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seq_printf(p, "%10u ", per_cpu(irq_stat, j).mce_exceptions);
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seq_printf(p, " Machine check exceptions\n");
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return 0;
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}
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/*
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* /proc/stat helpers
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*/
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u64 arch_irq_stat_cpu(unsigned int cpu)
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{
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u64 sum = per_cpu(irq_stat, cpu).timer_irqs;
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sum += per_cpu(irq_stat, cpu).pmu_irqs;
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sum += per_cpu(irq_stat, cpu).mce_exceptions;
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sum += per_cpu(irq_stat, cpu).spurious_irqs;
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return sum;
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}
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#ifdef CONFIG_HOTPLUG_CPU
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void migrate_irqs(void)
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{
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struct irq_desc *desc;
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unsigned int irq;
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static int warned;
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cpumask_var_t mask;
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const struct cpumask *map = cpu_online_mask;
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alloc_cpumask_var(&mask, GFP_KERNEL);
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for_each_irq_desc(irq, desc) {
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struct irq_data *data;
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struct irq_chip *chip;
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data = irq_desc_get_irq_data(desc);
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if (irqd_is_per_cpu(data))
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continue;
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chip = irq_data_get_irq_chip(data);
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cpumask_and(mask, data->affinity, map);
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if (cpumask_any(mask) >= nr_cpu_ids) {
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printk("Breaking affinity for irq %i\n", irq);
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cpumask_copy(mask, map);
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}
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if (chip->irq_set_affinity)
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chip->irq_set_affinity(data, mask, true);
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else if (desc->action && !(warned++))
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printk("Cannot set affinity for irq %i\n", irq);
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}
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free_cpumask_var(mask);
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local_irq_enable();
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mdelay(1);
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local_irq_disable();
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}
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#endif
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static inline void handle_one_irq(unsigned int irq)
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{
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struct thread_info *curtp, *irqtp;
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unsigned long saved_sp_limit;
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struct irq_desc *desc;
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desc = irq_to_desc(irq);
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if (!desc)
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return;
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/* Switch to the irq stack to handle this */
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curtp = current_thread_info();
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irqtp = hardirq_ctx[smp_processor_id()];
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if (curtp == irqtp) {
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/* We're already on the irq stack, just handle it */
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desc->handle_irq(irq, desc);
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return;
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}
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saved_sp_limit = current->thread.ksp_limit;
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|
|
|
irqtp->task = curtp->task;
|
|
irqtp->flags = 0;
|
|
|
|
/* Copy the softirq bits in preempt_count so that the
|
|
* softirq checks work in the hardirq context. */
|
|
irqtp->preempt_count = (irqtp->preempt_count & ~SOFTIRQ_MASK) |
|
|
(curtp->preempt_count & SOFTIRQ_MASK);
|
|
|
|
current->thread.ksp_limit = (unsigned long)irqtp +
|
|
_ALIGN_UP(sizeof(struct thread_info), 16);
|
|
|
|
call_handle_irq(irq, desc, irqtp, desc->handle_irq);
|
|
current->thread.ksp_limit = saved_sp_limit;
|
|
irqtp->task = NULL;
|
|
|
|
/* Set any flag that may have been set on the
|
|
* alternate stack
|
|
*/
|
|
if (irqtp->flags)
|
|
set_bits(irqtp->flags, &curtp->flags);
|
|
}
|
|
|
|
static inline void check_stack_overflow(void)
|
|
{
|
|
#ifdef CONFIG_DEBUG_STACKOVERFLOW
|
|
long sp;
|
|
|
|
sp = __get_SP() & (THREAD_SIZE-1);
|
|
|
|
/* check for stack overflow: is there less than 2KB free? */
|
|
if (unlikely(sp < (sizeof(struct thread_info) + 2048))) {
|
|
printk("do_IRQ: stack overflow: %ld\n",
|
|
sp - sizeof(struct thread_info));
|
|
dump_stack();
|
|
}
|
|
#endif
|
|
}
|
|
|
|
void do_IRQ(struct pt_regs *regs)
|
|
{
|
|
struct pt_regs *old_regs = set_irq_regs(regs);
|
|
unsigned int irq;
|
|
|
|
irq_enter();
|
|
|
|
trace_irq_entry(regs);
|
|
|
|
check_stack_overflow();
|
|
|
|
/*
|
|
* Query the platform PIC for the interrupt & ack it.
|
|
*
|
|
* This will typically lower the interrupt line to the CPU
|
|
*/
|
|
irq = ppc_md.get_irq();
|
|
|
|
/* We can hard enable interrupts now */
|
|
may_hard_irq_enable();
|
|
|
|
/* And finally process it */
|
|
if (irq != NO_IRQ)
|
|
handle_one_irq(irq);
|
|
else
|
|
__get_cpu_var(irq_stat).spurious_irqs++;
|
|
|
|
trace_irq_exit(regs);
|
|
|
|
irq_exit();
|
|
set_irq_regs(old_regs);
|
|
}
|
|
|
|
void __init init_IRQ(void)
|
|
{
|
|
if (ppc_md.init_IRQ)
|
|
ppc_md.init_IRQ();
|
|
|
|
exc_lvl_ctx_init();
|
|
|
|
irq_ctx_init();
|
|
}
|
|
|
|
#if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
|
|
struct thread_info *critirq_ctx[NR_CPUS] __read_mostly;
|
|
struct thread_info *dbgirq_ctx[NR_CPUS] __read_mostly;
|
|
struct thread_info *mcheckirq_ctx[NR_CPUS] __read_mostly;
|
|
|
|
void exc_lvl_ctx_init(void)
|
|
{
|
|
struct thread_info *tp;
|
|
int i, cpu_nr;
|
|
|
|
for_each_possible_cpu(i) {
|
|
#ifdef CONFIG_PPC64
|
|
cpu_nr = i;
|
|
#else
|
|
cpu_nr = get_hard_smp_processor_id(i);
|
|
#endif
|
|
memset((void *)critirq_ctx[cpu_nr], 0, THREAD_SIZE);
|
|
tp = critirq_ctx[cpu_nr];
|
|
tp->cpu = cpu_nr;
|
|
tp->preempt_count = 0;
|
|
|
|
#ifdef CONFIG_BOOKE
|
|
memset((void *)dbgirq_ctx[cpu_nr], 0, THREAD_SIZE);
|
|
tp = dbgirq_ctx[cpu_nr];
|
|
tp->cpu = cpu_nr;
|
|
tp->preempt_count = 0;
|
|
|
|
memset((void *)mcheckirq_ctx[cpu_nr], 0, THREAD_SIZE);
|
|
tp = mcheckirq_ctx[cpu_nr];
|
|
tp->cpu = cpu_nr;
|
|
tp->preempt_count = HARDIRQ_OFFSET;
|
|
#endif
|
|
}
|
|
}
|
|
#endif
|
|
|
|
struct thread_info *softirq_ctx[NR_CPUS] __read_mostly;
|
|
struct thread_info *hardirq_ctx[NR_CPUS] __read_mostly;
|
|
|
|
void irq_ctx_init(void)
|
|
{
|
|
struct thread_info *tp;
|
|
int i;
|
|
|
|
for_each_possible_cpu(i) {
|
|
memset((void *)softirq_ctx[i], 0, THREAD_SIZE);
|
|
tp = softirq_ctx[i];
|
|
tp->cpu = i;
|
|
tp->preempt_count = 0;
|
|
|
|
memset((void *)hardirq_ctx[i], 0, THREAD_SIZE);
|
|
tp = hardirq_ctx[i];
|
|
tp->cpu = i;
|
|
tp->preempt_count = HARDIRQ_OFFSET;
|
|
}
|
|
}
|
|
|
|
static inline void do_softirq_onstack(void)
|
|
{
|
|
struct thread_info *curtp, *irqtp;
|
|
unsigned long saved_sp_limit = current->thread.ksp_limit;
|
|
|
|
curtp = current_thread_info();
|
|
irqtp = softirq_ctx[smp_processor_id()];
|
|
irqtp->task = curtp->task;
|
|
irqtp->flags = 0;
|
|
current->thread.ksp_limit = (unsigned long)irqtp +
|
|
_ALIGN_UP(sizeof(struct thread_info), 16);
|
|
call_do_softirq(irqtp);
|
|
current->thread.ksp_limit = saved_sp_limit;
|
|
irqtp->task = NULL;
|
|
|
|
/* Set any flag that may have been set on the
|
|
* alternate stack
|
|
*/
|
|
if (irqtp->flags)
|
|
set_bits(irqtp->flags, &curtp->flags);
|
|
}
|
|
|
|
void do_softirq(void)
|
|
{
|
|
unsigned long flags;
|
|
|
|
if (in_interrupt())
|
|
return;
|
|
|
|
local_irq_save(flags);
|
|
|
|
if (local_softirq_pending())
|
|
do_softirq_onstack();
|
|
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
irq_hw_number_t virq_to_hw(unsigned int virq)
|
|
{
|
|
struct irq_data *irq_data = irq_get_irq_data(virq);
|
|
return WARN_ON(!irq_data) ? 0 : irq_data->hwirq;
|
|
}
|
|
EXPORT_SYMBOL_GPL(virq_to_hw);
|
|
|
|
#ifdef CONFIG_SMP
|
|
int irq_choose_cpu(const struct cpumask *mask)
|
|
{
|
|
int cpuid;
|
|
|
|
if (cpumask_equal(mask, cpu_online_mask)) {
|
|
static int irq_rover;
|
|
static DEFINE_RAW_SPINLOCK(irq_rover_lock);
|
|
unsigned long flags;
|
|
|
|
/* Round-robin distribution... */
|
|
do_round_robin:
|
|
raw_spin_lock_irqsave(&irq_rover_lock, flags);
|
|
|
|
irq_rover = cpumask_next(irq_rover, cpu_online_mask);
|
|
if (irq_rover >= nr_cpu_ids)
|
|
irq_rover = cpumask_first(cpu_online_mask);
|
|
|
|
cpuid = irq_rover;
|
|
|
|
raw_spin_unlock_irqrestore(&irq_rover_lock, flags);
|
|
} else {
|
|
cpuid = cpumask_first_and(mask, cpu_online_mask);
|
|
if (cpuid >= nr_cpu_ids)
|
|
goto do_round_robin;
|
|
}
|
|
|
|
return get_hard_smp_processor_id(cpuid);
|
|
}
|
|
#else
|
|
int irq_choose_cpu(const struct cpumask *mask)
|
|
{
|
|
return hard_smp_processor_id();
|
|
}
|
|
#endif
|
|
|
|
int arch_early_irq_init(void)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_PPC64
|
|
static int __init setup_noirqdistrib(char *str)
|
|
{
|
|
distribute_irqs = 0;
|
|
return 1;
|
|
}
|
|
|
|
__setup("noirqdistrib", setup_noirqdistrib);
|
|
#endif /* CONFIG_PPC64 */
|