Message ID | 20200318230145.72097-4-gshan@redhat.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | arm64: Dereference CPU operations indirectly | expand |
On Thu, Mar 19, 2020 at 10:01:44AM +1100, Gavin Shan wrote: > This introduces get_cpu_ops() to return the CPU operations according to > the given CPU index. For now, it simply returns the @cpu_ops[cpu] as > before. Also, helper function __cpu_try_die() is introduced to be shared > by cpu_die() and ipi_cpu_crash_stop(). So it shouldn't introduce any > functional changes. > > Signed-off-by: Gavin Shan <gshan@redhat.com> I think this makes the code easier to read, and the addition of a few lines is worthwhile, so: Acked-by: Mark Rutland <mark.rutland@arm.com> Mark. > --- > arch/arm64/include/asm/cpu_ops.h | 2 +- > arch/arm64/kernel/cpu_ops.c | 7 +++- > arch/arm64/kernel/cpuidle.c | 9 ++-- > arch/arm64/kernel/setup.c | 6 ++- > arch/arm64/kernel/smp.c | 70 +++++++++++++++++++++----------- > 5 files changed, 62 insertions(+), 32 deletions(-) > > diff --git a/arch/arm64/include/asm/cpu_ops.h b/arch/arm64/include/asm/cpu_ops.h > index baa13b5db2ca..d28e8f37d3b4 100644 > --- a/arch/arm64/include/asm/cpu_ops.h > +++ b/arch/arm64/include/asm/cpu_ops.h > @@ -55,8 +55,8 @@ struct cpu_operations { > #endif > }; > > -extern const struct cpu_operations *cpu_ops[NR_CPUS]; > int __init init_cpu_ops(int cpu); > +extern const struct cpu_operations *get_cpu_ops(int cpu); > > static inline void __init init_bootcpu_ops(void) > { > diff --git a/arch/arm64/kernel/cpu_ops.c b/arch/arm64/kernel/cpu_ops.c > index a6c3c816b618..e133011f64b5 100644 > --- a/arch/arm64/kernel/cpu_ops.c > +++ b/arch/arm64/kernel/cpu_ops.c > @@ -20,7 +20,7 @@ extern const struct cpu_operations acpi_parking_protocol_ops; > #endif > extern const struct cpu_operations cpu_psci_ops; > > -const struct cpu_operations *cpu_ops[NR_CPUS] __ro_after_init; > +static const struct cpu_operations *cpu_ops[NR_CPUS] __ro_after_init; > > static const struct cpu_operations *const dt_supported_cpu_ops[] __initconst = { > &smp_spin_table_ops, > @@ -111,3 +111,8 @@ int __init init_cpu_ops(int cpu) > > return 0; > } > + > +const struct cpu_operations *get_cpu_ops(int cpu) > +{ > + return cpu_ops[cpu]; > +} > diff --git a/arch/arm64/kernel/cpuidle.c b/arch/arm64/kernel/cpuidle.c > index e4d6af2fdec7..b512b5503f6e 100644 > --- a/arch/arm64/kernel/cpuidle.c > +++ b/arch/arm64/kernel/cpuidle.c > @@ -18,11 +18,11 @@ > > int arm_cpuidle_init(unsigned int cpu) > { > + const struct cpu_operations *ops = get_cpu_ops(cpu); > int ret = -EOPNOTSUPP; > > - if (cpu_ops[cpu] && cpu_ops[cpu]->cpu_suspend && > - cpu_ops[cpu]->cpu_init_idle) > - ret = cpu_ops[cpu]->cpu_init_idle(cpu); > + if (ops && ops->cpu_suspend && ops->cpu_init_idle) > + ret = ops->cpu_init_idle(cpu); > > return ret; > } > @@ -37,8 +37,9 @@ int arm_cpuidle_init(unsigned int cpu) > int arm_cpuidle_suspend(int index) > { > int cpu = smp_processor_id(); > + const struct cpu_operations *ops = get_cpu_ops(cpu); > > - return cpu_ops[cpu]->cpu_suspend(index); > + return ops->cpu_suspend(index); > } > > #ifdef CONFIG_ACPI > diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c > index f66bd260cce8..3fd2c11c09fc 100644 > --- a/arch/arm64/kernel/setup.c > +++ b/arch/arm64/kernel/setup.c > @@ -371,8 +371,10 @@ void __init setup_arch(char **cmdline_p) > static inline bool cpu_can_disable(unsigned int cpu) > { > #ifdef CONFIG_HOTPLUG_CPU > - if (cpu_ops[cpu] && cpu_ops[cpu]->cpu_can_disable) > - return cpu_ops[cpu]->cpu_can_disable(cpu); > + const struct cpu_operations *ops = get_cpu_ops(cpu); > + > + if (ops && ops->cpu_can_disable) > + return ops->cpu_can_disable(cpu); > #endif > return false; > } > diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c > index 6f8477d7f3be..e5c9862c271b 100644 > --- a/arch/arm64/kernel/smp.c > +++ b/arch/arm64/kernel/smp.c > @@ -93,8 +93,10 @@ static inline int op_cpu_kill(unsigned int cpu) > */ > static int boot_secondary(unsigned int cpu, struct task_struct *idle) > { > - if (cpu_ops[cpu]->cpu_boot) > - return cpu_ops[cpu]->cpu_boot(cpu); > + const struct cpu_operations *ops = get_cpu_ops(cpu); > + > + if (ops->cpu_boot) > + return ops->cpu_boot(cpu); > > return -EOPNOTSUPP; > } > @@ -196,6 +198,7 @@ asmlinkage notrace void secondary_start_kernel(void) > { > u64 mpidr = read_cpuid_mpidr() & MPIDR_HWID_BITMASK; > struct mm_struct *mm = &init_mm; > + const struct cpu_operations *ops; > unsigned int cpu; > > cpu = task_cpu(current); > @@ -227,8 +230,9 @@ asmlinkage notrace void secondary_start_kernel(void) > */ > check_local_cpu_capabilities(); > > - if (cpu_ops[cpu]->cpu_postboot) > - cpu_ops[cpu]->cpu_postboot(); > + ops = get_cpu_ops(cpu); > + if (ops->cpu_postboot) > + ops->cpu_postboot(); > > /* > * Log the CPU info before it is marked online and might get read. > @@ -266,19 +270,21 @@ asmlinkage notrace void secondary_start_kernel(void) > #ifdef CONFIG_HOTPLUG_CPU > static int op_cpu_disable(unsigned int cpu) > { > + const struct cpu_operations *ops = get_cpu_ops(cpu); > + > /* > * If we don't have a cpu_die method, abort before we reach the point > * of no return. CPU0 may not have an cpu_ops, so test for it. > */ > - if (!cpu_ops[cpu] || !cpu_ops[cpu]->cpu_die) > + if (!ops || !ops->cpu_die) > return -EOPNOTSUPP; > > /* > * We may need to abort a hot unplug for some other mechanism-specific > * reason. > */ > - if (cpu_ops[cpu]->cpu_disable) > - return cpu_ops[cpu]->cpu_disable(cpu); > + if (ops->cpu_disable) > + return ops->cpu_disable(cpu); > > return 0; > } > @@ -314,15 +320,17 @@ int __cpu_disable(void) > > static int op_cpu_kill(unsigned int cpu) > { > + const struct cpu_operations *ops = get_cpu_ops(cpu); > + > /* > * If we have no means of synchronising with the dying CPU, then assume > * that it is really dead. We can only wait for an arbitrary length of > * time and hope that it's dead, so let's skip the wait and just hope. > */ > - if (!cpu_ops[cpu]->cpu_kill) > + if (!ops->cpu_kill) > return 0; > > - return cpu_ops[cpu]->cpu_kill(cpu); > + return ops->cpu_kill(cpu); > } > > /* > @@ -357,6 +365,7 @@ void __cpu_die(unsigned int cpu) > void cpu_die(void) > { > unsigned int cpu = smp_processor_id(); > + const struct cpu_operations *ops = get_cpu_ops(cpu); > > idle_task_exit(); > > @@ -370,12 +379,22 @@ void cpu_die(void) > * mechanism must perform all required cache maintenance to ensure that > * no dirty lines are lost in the process of shutting down the CPU. > */ > - cpu_ops[cpu]->cpu_die(cpu); > + ops->cpu_die(cpu); > > BUG(); > } > #endif > > +static void __cpu_try_die(int cpu) > +{ > +#ifdef CONFIG_HOTPLUG_CPU > + const struct cpu_operations *ops = get_cpu_ops(cpu); > + > + if (ops && ops->cpu_die) > + ops->cpu_die(cpu); > +#endif > +} > + > /* > * Kill the calling secondary CPU, early in bringup before it is turned > * online. > @@ -389,12 +408,11 @@ void cpu_die_early(void) > /* Mark this CPU absent */ > set_cpu_present(cpu, 0); > > -#ifdef CONFIG_HOTPLUG_CPU > - update_cpu_boot_status(CPU_KILL_ME); > - /* Check if we can park ourselves */ > - if (cpu_ops[cpu] && cpu_ops[cpu]->cpu_die) > - cpu_ops[cpu]->cpu_die(cpu); > -#endif > + if (IS_ENABLED(CONFIG_HOTPLUG_CPU)) { > + update_cpu_boot_status(CPU_KILL_ME); > + __cpu_try_die(cpu); > + } > + > update_cpu_boot_status(CPU_STUCK_IN_KERNEL); > > cpu_park_loop(); > @@ -488,10 +506,13 @@ static bool __init is_mpidr_duplicate(unsigned int cpu, u64 hwid) > */ > static int __init smp_cpu_setup(int cpu) > { > + const struct cpu_operations *ops; > + > if (init_cpu_ops(cpu)) > return -ENODEV; > > - if (cpu_ops[cpu]->cpu_init(cpu)) > + ops = get_cpu_ops(cpu); > + if (ops->cpu_init(cpu)) > return -ENODEV; > > set_cpu_possible(cpu, true); > @@ -714,6 +735,7 @@ void __init smp_init_cpus(void) > > void __init smp_prepare_cpus(unsigned int max_cpus) > { > + const struct cpu_operations *ops; > int err; > unsigned int cpu; > unsigned int this_cpu; > @@ -744,10 +766,11 @@ void __init smp_prepare_cpus(unsigned int max_cpus) > if (cpu == smp_processor_id()) > continue; > > - if (!cpu_ops[cpu]) > + ops = get_cpu_ops(cpu); > + if (!ops) > continue; > > - err = cpu_ops[cpu]->cpu_prepare(cpu); > + err = ops->cpu_prepare(cpu); > if (err) > continue; > > @@ -863,10 +886,8 @@ static void ipi_cpu_crash_stop(unsigned int cpu, struct pt_regs *regs) > local_irq_disable(); > sdei_mask_local_cpu(); > > -#ifdef CONFIG_HOTPLUG_CPU > - if (cpu_ops[cpu]->cpu_die) > - cpu_ops[cpu]->cpu_die(cpu); > -#endif > + if (IS_ENABLED(CONFIG_HOTPLUG_CPU)) > + __cpu_try_die(cpu); > > /* just in case */ > cpu_park_loop(); > @@ -1044,8 +1065,9 @@ static bool have_cpu_die(void) > { > #ifdef CONFIG_HOTPLUG_CPU > int any_cpu = raw_smp_processor_id(); > + const struct cpu_operations *ops = get_cpu_ops(any_cpu); > > - if (cpu_ops[any_cpu] && cpu_ops[any_cpu]->cpu_die) > + if (ops && ops->cpu_die) > return true; > #endif > return false; > -- > 2.23.0 >
diff --git a/arch/arm64/include/asm/cpu_ops.h b/arch/arm64/include/asm/cpu_ops.h index baa13b5db2ca..d28e8f37d3b4 100644 --- a/arch/arm64/include/asm/cpu_ops.h +++ b/arch/arm64/include/asm/cpu_ops.h @@ -55,8 +55,8 @@ struct cpu_operations { #endif }; -extern const struct cpu_operations *cpu_ops[NR_CPUS]; int __init init_cpu_ops(int cpu); +extern const struct cpu_operations *get_cpu_ops(int cpu); static inline void __init init_bootcpu_ops(void) { diff --git a/arch/arm64/kernel/cpu_ops.c b/arch/arm64/kernel/cpu_ops.c index a6c3c816b618..e133011f64b5 100644 --- a/arch/arm64/kernel/cpu_ops.c +++ b/arch/arm64/kernel/cpu_ops.c @@ -20,7 +20,7 @@ extern const struct cpu_operations acpi_parking_protocol_ops; #endif extern const struct cpu_operations cpu_psci_ops; -const struct cpu_operations *cpu_ops[NR_CPUS] __ro_after_init; +static const struct cpu_operations *cpu_ops[NR_CPUS] __ro_after_init; static const struct cpu_operations *const dt_supported_cpu_ops[] __initconst = { &smp_spin_table_ops, @@ -111,3 +111,8 @@ int __init init_cpu_ops(int cpu) return 0; } + +const struct cpu_operations *get_cpu_ops(int cpu) +{ + return cpu_ops[cpu]; +} diff --git a/arch/arm64/kernel/cpuidle.c b/arch/arm64/kernel/cpuidle.c index e4d6af2fdec7..b512b5503f6e 100644 --- a/arch/arm64/kernel/cpuidle.c +++ b/arch/arm64/kernel/cpuidle.c @@ -18,11 +18,11 @@ int arm_cpuidle_init(unsigned int cpu) { + const struct cpu_operations *ops = get_cpu_ops(cpu); int ret = -EOPNOTSUPP; - if (cpu_ops[cpu] && cpu_ops[cpu]->cpu_suspend && - cpu_ops[cpu]->cpu_init_idle) - ret = cpu_ops[cpu]->cpu_init_idle(cpu); + if (ops && ops->cpu_suspend && ops->cpu_init_idle) + ret = ops->cpu_init_idle(cpu); return ret; } @@ -37,8 +37,9 @@ int arm_cpuidle_init(unsigned int cpu) int arm_cpuidle_suspend(int index) { int cpu = smp_processor_id(); + const struct cpu_operations *ops = get_cpu_ops(cpu); - return cpu_ops[cpu]->cpu_suspend(index); + return ops->cpu_suspend(index); } #ifdef CONFIG_ACPI diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index f66bd260cce8..3fd2c11c09fc 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -371,8 +371,10 @@ void __init setup_arch(char **cmdline_p) static inline bool cpu_can_disable(unsigned int cpu) { #ifdef CONFIG_HOTPLUG_CPU - if (cpu_ops[cpu] && cpu_ops[cpu]->cpu_can_disable) - return cpu_ops[cpu]->cpu_can_disable(cpu); + const struct cpu_operations *ops = get_cpu_ops(cpu); + + if (ops && ops->cpu_can_disable) + return ops->cpu_can_disable(cpu); #endif return false; } diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 6f8477d7f3be..e5c9862c271b 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -93,8 +93,10 @@ static inline int op_cpu_kill(unsigned int cpu) */ static int boot_secondary(unsigned int cpu, struct task_struct *idle) { - if (cpu_ops[cpu]->cpu_boot) - return cpu_ops[cpu]->cpu_boot(cpu); + const struct cpu_operations *ops = get_cpu_ops(cpu); + + if (ops->cpu_boot) + return ops->cpu_boot(cpu); return -EOPNOTSUPP; } @@ -196,6 +198,7 @@ asmlinkage notrace void secondary_start_kernel(void) { u64 mpidr = read_cpuid_mpidr() & MPIDR_HWID_BITMASK; struct mm_struct *mm = &init_mm; + const struct cpu_operations *ops; unsigned int cpu; cpu = task_cpu(current); @@ -227,8 +230,9 @@ asmlinkage notrace void secondary_start_kernel(void) */ check_local_cpu_capabilities(); - if (cpu_ops[cpu]->cpu_postboot) - cpu_ops[cpu]->cpu_postboot(); + ops = get_cpu_ops(cpu); + if (ops->cpu_postboot) + ops->cpu_postboot(); /* * Log the CPU info before it is marked online and might get read. @@ -266,19 +270,21 @@ asmlinkage notrace void secondary_start_kernel(void) #ifdef CONFIG_HOTPLUG_CPU static int op_cpu_disable(unsigned int cpu) { + const struct cpu_operations *ops = get_cpu_ops(cpu); + /* * If we don't have a cpu_die method, abort before we reach the point * of no return. CPU0 may not have an cpu_ops, so test for it. */ - if (!cpu_ops[cpu] || !cpu_ops[cpu]->cpu_die) + if (!ops || !ops->cpu_die) return -EOPNOTSUPP; /* * We may need to abort a hot unplug for some other mechanism-specific * reason. */ - if (cpu_ops[cpu]->cpu_disable) - return cpu_ops[cpu]->cpu_disable(cpu); + if (ops->cpu_disable) + return ops->cpu_disable(cpu); return 0; } @@ -314,15 +320,17 @@ int __cpu_disable(void) static int op_cpu_kill(unsigned int cpu) { + const struct cpu_operations *ops = get_cpu_ops(cpu); + /* * If we have no means of synchronising with the dying CPU, then assume * that it is really dead. We can only wait for an arbitrary length of * time and hope that it's dead, so let's skip the wait and just hope. */ - if (!cpu_ops[cpu]->cpu_kill) + if (!ops->cpu_kill) return 0; - return cpu_ops[cpu]->cpu_kill(cpu); + return ops->cpu_kill(cpu); } /* @@ -357,6 +365,7 @@ void __cpu_die(unsigned int cpu) void cpu_die(void) { unsigned int cpu = smp_processor_id(); + const struct cpu_operations *ops = get_cpu_ops(cpu); idle_task_exit(); @@ -370,12 +379,22 @@ void cpu_die(void) * mechanism must perform all required cache maintenance to ensure that * no dirty lines are lost in the process of shutting down the CPU. */ - cpu_ops[cpu]->cpu_die(cpu); + ops->cpu_die(cpu); BUG(); } #endif +static void __cpu_try_die(int cpu) +{ +#ifdef CONFIG_HOTPLUG_CPU + const struct cpu_operations *ops = get_cpu_ops(cpu); + + if (ops && ops->cpu_die) + ops->cpu_die(cpu); +#endif +} + /* * Kill the calling secondary CPU, early in bringup before it is turned * online. @@ -389,12 +408,11 @@ void cpu_die_early(void) /* Mark this CPU absent */ set_cpu_present(cpu, 0); -#ifdef CONFIG_HOTPLUG_CPU - update_cpu_boot_status(CPU_KILL_ME); - /* Check if we can park ourselves */ - if (cpu_ops[cpu] && cpu_ops[cpu]->cpu_die) - cpu_ops[cpu]->cpu_die(cpu); -#endif + if (IS_ENABLED(CONFIG_HOTPLUG_CPU)) { + update_cpu_boot_status(CPU_KILL_ME); + __cpu_try_die(cpu); + } + update_cpu_boot_status(CPU_STUCK_IN_KERNEL); cpu_park_loop(); @@ -488,10 +506,13 @@ static bool __init is_mpidr_duplicate(unsigned int cpu, u64 hwid) */ static int __init smp_cpu_setup(int cpu) { + const struct cpu_operations *ops; + if (init_cpu_ops(cpu)) return -ENODEV; - if (cpu_ops[cpu]->cpu_init(cpu)) + ops = get_cpu_ops(cpu); + if (ops->cpu_init(cpu)) return -ENODEV; set_cpu_possible(cpu, true); @@ -714,6 +735,7 @@ void __init smp_init_cpus(void) void __init smp_prepare_cpus(unsigned int max_cpus) { + const struct cpu_operations *ops; int err; unsigned int cpu; unsigned int this_cpu; @@ -744,10 +766,11 @@ void __init smp_prepare_cpus(unsigned int max_cpus) if (cpu == smp_processor_id()) continue; - if (!cpu_ops[cpu]) + ops = get_cpu_ops(cpu); + if (!ops) continue; - err = cpu_ops[cpu]->cpu_prepare(cpu); + err = ops->cpu_prepare(cpu); if (err) continue; @@ -863,10 +886,8 @@ static void ipi_cpu_crash_stop(unsigned int cpu, struct pt_regs *regs) local_irq_disable(); sdei_mask_local_cpu(); -#ifdef CONFIG_HOTPLUG_CPU - if (cpu_ops[cpu]->cpu_die) - cpu_ops[cpu]->cpu_die(cpu); -#endif + if (IS_ENABLED(CONFIG_HOTPLUG_CPU)) + __cpu_try_die(cpu); /* just in case */ cpu_park_loop(); @@ -1044,8 +1065,9 @@ static bool have_cpu_die(void) { #ifdef CONFIG_HOTPLUG_CPU int any_cpu = raw_smp_processor_id(); + const struct cpu_operations *ops = get_cpu_ops(any_cpu); - if (cpu_ops[any_cpu] && cpu_ops[any_cpu]->cpu_die) + if (ops && ops->cpu_die) return true; #endif return false;
This introduces get_cpu_ops() to return the CPU operations according to the given CPU index. For now, it simply returns the @cpu_ops[cpu] as before. Also, helper function __cpu_try_die() is introduced to be shared by cpu_die() and ipi_cpu_crash_stop(). So it shouldn't introduce any functional changes. Signed-off-by: Gavin Shan <gshan@redhat.com> --- arch/arm64/include/asm/cpu_ops.h | 2 +- arch/arm64/kernel/cpu_ops.c | 7 +++- arch/arm64/kernel/cpuidle.c | 9 ++-- arch/arm64/kernel/setup.c | 6 ++- arch/arm64/kernel/smp.c | 70 +++++++++++++++++++++----------- 5 files changed, 62 insertions(+), 32 deletions(-)