Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus: stop_machine: fix up ftrace.c stop_machine: Wean existing callers off stop_machine_run() stop_machine(): stop_machine_run() changed to use cpu mask Hotplug CPU: don't check cpu_online after take_cpu_down Simplify stop_machine stop_machine: add ALL_CPUS option module: fix build warning with !CONFIG_KALLSYMS
This commit is contained in:
commit
37eaf8c746
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@ -197,7 +197,7 @@ void __kprobes arch_arm_kprobe(struct kprobe *p)
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args.new = BREAKPOINT_INSTRUCTION;
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kcb->kprobe_status = KPROBE_SWAP_INST;
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stop_machine_run(swap_instruction, &args, NR_CPUS);
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stop_machine(swap_instruction, &args, NULL);
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kcb->kprobe_status = status;
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}
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@ -212,7 +212,7 @@ void __kprobes arch_disarm_kprobe(struct kprobe *p)
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args.new = p->opcode;
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kcb->kprobe_status = KPROBE_SWAP_INST;
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stop_machine_run(swap_instruction, &args, NR_CPUS);
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stop_machine(swap_instruction, &args, NULL);
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kcb->kprobe_status = status;
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}
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@ -331,7 +331,7 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
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* No kprobe at this address. The fault has not been
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* caused by a kprobe breakpoint. The race of breakpoint
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* vs. kprobe remove does not exist because on s390 we
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* use stop_machine_run to arm/disarm the breakpoints.
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* use stop_machine to arm/disarm the breakpoints.
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*/
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goto no_kprobe;
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@ -241,7 +241,7 @@ static int __init intel_rng_hw_init(void *_intel_rng_hw)
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struct intel_rng_hw *intel_rng_hw = _intel_rng_hw;
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u8 mfc, dvc;
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/* interrupts disabled in stop_machine_run call */
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/* interrupts disabled in stop_machine call */
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if (!(intel_rng_hw->fwh_dec_en1_val & FWH_F8_EN_MASK))
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pci_write_config_byte(intel_rng_hw->dev,
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@ -365,10 +365,10 @@ static int __init mod_init(void)
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* location with the Read ID command, all activity on the system
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* must be stopped until the state is back to normal.
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*
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* Use stop_machine_run because IPIs can be blocked by disabling
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* Use stop_machine because IPIs can be blocked by disabling
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* interrupts.
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*/
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err = stop_machine_run(intel_rng_hw_init, intel_rng_hw, NR_CPUS);
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err = stop_machine(intel_rng_hw_init, intel_rng_hw, NULL);
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pci_dev_put(dev);
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iounmap(intel_rng_hw->mem);
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kfree(intel_rng_hw);
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@ -5,41 +5,43 @@
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(and more). So the "read" side to such a lock is anything which
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diables preeempt. */
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#include <linux/cpu.h>
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#include <linux/cpumask.h>
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#include <asm/system.h>
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#if defined(CONFIG_STOP_MACHINE) && defined(CONFIG_SMP)
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/* Deprecated, but useful for transition. */
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#define ALL_CPUS ~0U
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/**
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* stop_machine_run: freeze the machine on all CPUs and run this function
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* stop_machine: freeze the machine on all CPUs and run this function
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* @fn: the function to run
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* @data: the data ptr for the @fn()
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* @cpu: the cpu to run @fn() on (or any, if @cpu == NR_CPUS.
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* @cpus: the cpus to run the @fn() on (NULL = any online cpu)
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*
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* Description: This causes a thread to be scheduled on every other cpu,
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* each of which disables interrupts, and finally interrupts are disabled
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* on the current CPU. The result is that noone is holding a spinlock
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* or inside any other preempt-disabled region when @fn() runs.
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* Description: This causes a thread to be scheduled on every cpu,
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* each of which disables interrupts. The result is that noone is
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* holding a spinlock or inside any other preempt-disabled region when
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* @fn() runs.
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*
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* This can be thought of as a very heavy write lock, equivalent to
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* grabbing every spinlock in the kernel. */
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int stop_machine_run(int (*fn)(void *), void *data, unsigned int cpu);
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int stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus);
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/**
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* __stop_machine_run: freeze the machine on all CPUs and run this function
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* __stop_machine: freeze the machine on all CPUs and run this function
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* @fn: the function to run
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* @data: the data ptr for the @fn
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* @cpu: the cpu to run @fn on (or any, if @cpu == NR_CPUS.
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* @cpus: the cpus to run the @fn() on (NULL = any online cpu)
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*
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* Description: This is a special version of the above, which returns the
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* thread which has run @fn(): kthread_stop will return the return value
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* of @fn(). Used by hotplug cpu.
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* Description: This is a special version of the above, which assumes cpus
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* won't come or go while it's being called. Used by hotplug cpu.
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*/
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struct task_struct *__stop_machine_run(int (*fn)(void *), void *data,
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unsigned int cpu);
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int __stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus);
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#else
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static inline int stop_machine_run(int (*fn)(void *), void *data,
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unsigned int cpu)
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static inline int stop_machine(int (*fn)(void *), void *data,
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const cpumask_t *cpus)
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{
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int ret;
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local_irq_disable();
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@ -48,4 +50,18 @@ static inline int stop_machine_run(int (*fn)(void *), void *data,
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return ret;
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}
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#endif /* CONFIG_SMP */
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static inline int __deprecated stop_machine_run(int (*fn)(void *), void *data,
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unsigned int cpu)
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{
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/* If they don't care which cpu fn runs on, just pick one. */
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if (cpu == NR_CPUS)
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return stop_machine(fn, data, NULL);
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else if (cpu == ~0U)
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return stop_machine(fn, data, &cpu_possible_map);
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else {
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cpumask_t cpus = cpumask_of_cpu(cpu);
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return stop_machine(fn, data, &cpus);
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}
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}
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#endif /* _LINUX_STOP_MACHINE */
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14
kernel/cpu.c
14
kernel/cpu.c
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@ -216,7 +216,6 @@ static int __ref take_cpu_down(void *_param)
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static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
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{
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int err, nr_calls = 0;
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struct task_struct *p;
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cpumask_t old_allowed, tmp;
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void *hcpu = (void *)(long)cpu;
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unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0;
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@ -249,21 +248,18 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
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cpus_setall(tmp);
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cpu_clear(cpu, tmp);
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set_cpus_allowed_ptr(current, &tmp);
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tmp = cpumask_of_cpu(cpu);
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p = __stop_machine_run(take_cpu_down, &tcd_param, cpu);
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if (IS_ERR(p) || cpu_online(cpu)) {
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err = __stop_machine(take_cpu_down, &tcd_param, &tmp);
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if (err) {
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/* CPU didn't die: tell everyone. Can't complain. */
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if (raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod,
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hcpu) == NOTIFY_BAD)
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BUG();
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if (IS_ERR(p)) {
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err = PTR_ERR(p);
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goto out_allowed;
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}
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goto out_thread;
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}
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BUG_ON(cpu_online(cpu));
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/* Wait for it to sleep (leaving idle task). */
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while (!idle_cpu(cpu))
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@ -279,8 +275,6 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
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check_for_tasks(cpu);
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out_thread:
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err = kthread_stop(p);
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out_allowed:
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set_cpus_allowed_ptr(current, &old_allowed);
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out_release:
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|
|
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@ -325,18 +325,6 @@ static unsigned long find_symbol(const char *name,
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return -ENOENT;
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}
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/* lookup symbol in given range of kernel_symbols */
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static const struct kernel_symbol *lookup_symbol(const char *name,
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const struct kernel_symbol *start,
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const struct kernel_symbol *stop)
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{
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const struct kernel_symbol *ks = start;
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for (; ks < stop; ks++)
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if (strcmp(ks->name, name) == 0)
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return ks;
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return NULL;
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}
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/* Search for module by name: must hold module_mutex. */
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static struct module *find_module(const char *name)
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{
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@ -690,7 +678,7 @@ static int try_stop_module(struct module *mod, int flags, int *forced)
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if (flags & O_NONBLOCK) {
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struct stopref sref = { mod, flags, forced };
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return stop_machine_run(__try_stop_module, &sref, NR_CPUS);
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return stop_machine(__try_stop_module, &sref, NULL);
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} else {
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/* We don't need to stop the machine for this. */
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mod->state = MODULE_STATE_GOING;
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@ -1428,7 +1416,7 @@ static int __unlink_module(void *_mod)
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static void free_module(struct module *mod)
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{
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/* Delete from various lists */
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stop_machine_run(__unlink_module, mod, NR_CPUS);
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stop_machine(__unlink_module, mod, NULL);
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remove_notes_attrs(mod);
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remove_sect_attrs(mod);
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mod_kobject_remove(mod);
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|
@ -1703,6 +1691,19 @@ static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
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}
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#ifdef CONFIG_KALLSYMS
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/* lookup symbol in given range of kernel_symbols */
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static const struct kernel_symbol *lookup_symbol(const char *name,
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const struct kernel_symbol *start,
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const struct kernel_symbol *stop)
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{
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const struct kernel_symbol *ks = start;
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for (; ks < stop; ks++)
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if (strcmp(ks->name, name) == 0)
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return ks;
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return NULL;
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}
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|
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static int is_exported(const char *name, const struct module *mod)
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{
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if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab))
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|
@ -2196,7 +2197,7 @@ static struct module *load_module(void __user *umod,
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/* Now sew it into the lists so we can get lockdep and oops
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* info during argument parsing. Noone should access us, since
|
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* strong_try_module_get() will fail. */
|
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stop_machine_run(__link_module, mod, NR_CPUS);
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stop_machine(__link_module, mod, NULL);
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|
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/* Size of section 0 is 0, so this works well if no params */
|
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err = parse_args(mod->name, mod->args,
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|
@ -2230,7 +2231,7 @@ static struct module *load_module(void __user *umod,
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return mod;
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|
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unlink:
|
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stop_machine_run(__unlink_module, mod, NR_CPUS);
|
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stop_machine(__unlink_module, mod, NULL);
|
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module_arch_cleanup(mod);
|
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cleanup:
|
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kobject_del(&mod->mkobj.kobj);
|
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|
|
|
@ -91,8 +91,8 @@ static void force_quiescent_state(struct rcu_data *rdp,
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* rdp->cpu is the current cpu.
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*
|
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* cpu_online_map is updated by the _cpu_down()
|
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* using stop_machine_run(). Since we're in irqs disabled
|
||||
* section, stop_machine_run() is not exectuting, hence
|
||||
* using __stop_machine(). Since we're in irqs disabled
|
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* section, __stop_machine() is not exectuting, hence
|
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* the cpu_online_map is stable.
|
||||
*
|
||||
* However, a cpu might have been offlined _just_ before
|
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|
|
|
@ -1,4 +1,4 @@
|
|||
/* Copyright 2005 Rusty Russell rusty@rustcorp.com.au IBM Corporation.
|
||||
/* Copyright 2008, 2005 Rusty Russell rusty@rustcorp.com.au IBM Corporation.
|
||||
* GPL v2 and any later version.
|
||||
*/
|
||||
#include <linux/cpu.h>
|
||||
|
@ -13,204 +13,178 @@
|
|||
#include <asm/atomic.h>
|
||||
#include <asm/uaccess.h>
|
||||
|
||||
/* Since we effect priority and affinity (both of which are visible
|
||||
* to, and settable by outside processes) we do indirection via a
|
||||
* kthread. */
|
||||
|
||||
/* Thread to stop each CPU in user context. */
|
||||
/* This controls the threads on each CPU. */
|
||||
enum stopmachine_state {
|
||||
STOPMACHINE_WAIT,
|
||||
/* Dummy starting state for thread. */
|
||||
STOPMACHINE_NONE,
|
||||
/* Awaiting everyone to be scheduled. */
|
||||
STOPMACHINE_PREPARE,
|
||||
/* Disable interrupts. */
|
||||
STOPMACHINE_DISABLE_IRQ,
|
||||
/* Run the function */
|
||||
STOPMACHINE_RUN,
|
||||
/* Exit */
|
||||
STOPMACHINE_EXIT,
|
||||
};
|
||||
|
||||
static enum stopmachine_state stopmachine_state;
|
||||
static unsigned int stopmachine_num_threads;
|
||||
static atomic_t stopmachine_thread_ack;
|
||||
|
||||
static int stopmachine(void *cpu)
|
||||
{
|
||||
int irqs_disabled = 0;
|
||||
int prepared = 0;
|
||||
cpumask_of_cpu_ptr(cpumask, (int)(long)cpu);
|
||||
|
||||
set_cpus_allowed_ptr(current, cpumask);
|
||||
|
||||
/* Ack: we are alive */
|
||||
smp_mb(); /* Theoretically the ack = 0 might not be on this CPU yet. */
|
||||
atomic_inc(&stopmachine_thread_ack);
|
||||
|
||||
/* Simple state machine */
|
||||
while (stopmachine_state != STOPMACHINE_EXIT) {
|
||||
if (stopmachine_state == STOPMACHINE_DISABLE_IRQ
|
||||
&& !irqs_disabled) {
|
||||
local_irq_disable();
|
||||
hard_irq_disable();
|
||||
irqs_disabled = 1;
|
||||
/* Ack: irqs disabled. */
|
||||
smp_mb(); /* Must read state first. */
|
||||
atomic_inc(&stopmachine_thread_ack);
|
||||
} else if (stopmachine_state == STOPMACHINE_PREPARE
|
||||
&& !prepared) {
|
||||
/* Everyone is in place, hold CPU. */
|
||||
preempt_disable();
|
||||
prepared = 1;
|
||||
smp_mb(); /* Must read state first. */
|
||||
atomic_inc(&stopmachine_thread_ack);
|
||||
}
|
||||
/* Yield in first stage: migration threads need to
|
||||
* help our sisters onto their CPUs. */
|
||||
if (!prepared && !irqs_disabled)
|
||||
yield();
|
||||
cpu_relax();
|
||||
}
|
||||
|
||||
/* Ack: we are exiting. */
|
||||
smp_mb(); /* Must read state first. */
|
||||
atomic_inc(&stopmachine_thread_ack);
|
||||
|
||||
if (irqs_disabled)
|
||||
local_irq_enable();
|
||||
if (prepared)
|
||||
preempt_enable();
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Change the thread state */
|
||||
static void stopmachine_set_state(enum stopmachine_state state)
|
||||
{
|
||||
atomic_set(&stopmachine_thread_ack, 0);
|
||||
smp_wmb();
|
||||
stopmachine_state = state;
|
||||
while (atomic_read(&stopmachine_thread_ack) != stopmachine_num_threads)
|
||||
cpu_relax();
|
||||
}
|
||||
|
||||
static int stop_machine(void)
|
||||
{
|
||||
int i, ret = 0;
|
||||
|
||||
atomic_set(&stopmachine_thread_ack, 0);
|
||||
stopmachine_num_threads = 0;
|
||||
stopmachine_state = STOPMACHINE_WAIT;
|
||||
|
||||
for_each_online_cpu(i) {
|
||||
if (i == raw_smp_processor_id())
|
||||
continue;
|
||||
ret = kernel_thread(stopmachine, (void *)(long)i,CLONE_KERNEL);
|
||||
if (ret < 0)
|
||||
break;
|
||||
stopmachine_num_threads++;
|
||||
}
|
||||
|
||||
/* Wait for them all to come to life. */
|
||||
while (atomic_read(&stopmachine_thread_ack) != stopmachine_num_threads) {
|
||||
yield();
|
||||
cpu_relax();
|
||||
}
|
||||
|
||||
/* If some failed, kill them all. */
|
||||
if (ret < 0) {
|
||||
stopmachine_set_state(STOPMACHINE_EXIT);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/* Now they are all started, make them hold the CPUs, ready. */
|
||||
preempt_disable();
|
||||
stopmachine_set_state(STOPMACHINE_PREPARE);
|
||||
|
||||
/* Make them disable irqs. */
|
||||
local_irq_disable();
|
||||
hard_irq_disable();
|
||||
stopmachine_set_state(STOPMACHINE_DISABLE_IRQ);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void restart_machine(void)
|
||||
{
|
||||
stopmachine_set_state(STOPMACHINE_EXIT);
|
||||
local_irq_enable();
|
||||
preempt_enable_no_resched();
|
||||
}
|
||||
static enum stopmachine_state state;
|
||||
|
||||
struct stop_machine_data {
|
||||
int (*fn)(void *);
|
||||
void *data;
|
||||
struct completion done;
|
||||
int fnret;
|
||||
};
|
||||
|
||||
static int do_stop(void *_smdata)
|
||||
/* Like num_online_cpus(), but hotplug cpu uses us, so we need this. */
|
||||
static unsigned int num_threads;
|
||||
static atomic_t thread_ack;
|
||||
static struct completion finished;
|
||||
static DEFINE_MUTEX(lock);
|
||||
|
||||
static void set_state(enum stopmachine_state newstate)
|
||||
{
|
||||
struct stop_machine_data *smdata = _smdata;
|
||||
int ret;
|
||||
|
||||
ret = stop_machine();
|
||||
if (ret == 0) {
|
||||
ret = smdata->fn(smdata->data);
|
||||
restart_machine();
|
||||
}
|
||||
|
||||
/* We're done: you can kthread_stop us now */
|
||||
complete(&smdata->done);
|
||||
|
||||
/* Wait for kthread_stop */
|
||||
set_current_state(TASK_INTERRUPTIBLE);
|
||||
while (!kthread_should_stop()) {
|
||||
schedule();
|
||||
set_current_state(TASK_INTERRUPTIBLE);
|
||||
}
|
||||
__set_current_state(TASK_RUNNING);
|
||||
return ret;
|
||||
/* Reset ack counter. */
|
||||
atomic_set(&thread_ack, num_threads);
|
||||
smp_wmb();
|
||||
state = newstate;
|
||||
}
|
||||
|
||||
struct task_struct *__stop_machine_run(int (*fn)(void *), void *data,
|
||||
unsigned int cpu)
|
||||
/* Last one to ack a state moves to the next state. */
|
||||
static void ack_state(void)
|
||||
{
|
||||
static DEFINE_MUTEX(stopmachine_mutex);
|
||||
struct stop_machine_data smdata;
|
||||
struct task_struct *p;
|
||||
if (atomic_dec_and_test(&thread_ack)) {
|
||||
/* If we're the last one to ack the EXIT, we're finished. */
|
||||
if (state == STOPMACHINE_EXIT)
|
||||
complete(&finished);
|
||||
else
|
||||
set_state(state + 1);
|
||||
}
|
||||
}
|
||||
|
||||
smdata.fn = fn;
|
||||
smdata.data = data;
|
||||
init_completion(&smdata.done);
|
||||
/* This is the actual thread which stops the CPU. It exits by itself rather
|
||||
* than waiting for kthread_stop(), because it's easier for hotplug CPU. */
|
||||
static int stop_cpu(struct stop_machine_data *smdata)
|
||||
{
|
||||
enum stopmachine_state curstate = STOPMACHINE_NONE;
|
||||
int uninitialized_var(ret);
|
||||
|
||||
mutex_lock(&stopmachine_mutex);
|
||||
/* Simple state machine */
|
||||
do {
|
||||
/* Chill out and ensure we re-read stopmachine_state. */
|
||||
cpu_relax();
|
||||
if (state != curstate) {
|
||||
curstate = state;
|
||||
switch (curstate) {
|
||||
case STOPMACHINE_DISABLE_IRQ:
|
||||
local_irq_disable();
|
||||
hard_irq_disable();
|
||||
break;
|
||||
case STOPMACHINE_RUN:
|
||||
/* |= allows error detection if functions on
|
||||
* multiple CPUs. */
|
||||
smdata->fnret |= smdata->fn(smdata->data);
|
||||
break;
|
||||
default:
|
||||
break;
|
||||
}
|
||||
ack_state();
|
||||
}
|
||||
} while (curstate != STOPMACHINE_EXIT);
|
||||
|
||||
/* If they don't care which CPU fn runs on, bind to any online one. */
|
||||
if (cpu == NR_CPUS)
|
||||
cpu = raw_smp_processor_id();
|
||||
local_irq_enable();
|
||||
do_exit(0);
|
||||
}
|
||||
|
||||
p = kthread_create(do_stop, &smdata, "kstopmachine");
|
||||
if (!IS_ERR(p)) {
|
||||
/* Callback for CPUs which aren't supposed to do anything. */
|
||||
static int chill(void *unused)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
|
||||
int __stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus)
|
||||
{
|
||||
int i, err;
|
||||
struct stop_machine_data active, idle;
|
||||
struct task_struct **threads;
|
||||
|
||||
active.fn = fn;
|
||||
active.data = data;
|
||||
active.fnret = 0;
|
||||
idle.fn = chill;
|
||||
idle.data = NULL;
|
||||
|
||||
/* This could be too big for stack on large machines. */
|
||||
threads = kcalloc(NR_CPUS, sizeof(threads[0]), GFP_KERNEL);
|
||||
if (!threads)
|
||||
return -ENOMEM;
|
||||
|
||||
/* Set up initial state. */
|
||||
mutex_lock(&lock);
|
||||
init_completion(&finished);
|
||||
num_threads = num_online_cpus();
|
||||
set_state(STOPMACHINE_PREPARE);
|
||||
|
||||
for_each_online_cpu(i) {
|
||||
struct stop_machine_data *smdata = &idle;
|
||||
struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 };
|
||||
|
||||
/* One high-prio thread per cpu. We'll do this one. */
|
||||
sched_setscheduler_nocheck(p, SCHED_FIFO, ¶m);
|
||||
kthread_bind(p, cpu);
|
||||
wake_up_process(p);
|
||||
wait_for_completion(&smdata.done);
|
||||
if (!cpus) {
|
||||
if (i == first_cpu(cpu_online_map))
|
||||
smdata = &active;
|
||||
} else {
|
||||
if (cpu_isset(i, *cpus))
|
||||
smdata = &active;
|
||||
}
|
||||
mutex_unlock(&stopmachine_mutex);
|
||||
return p;
|
||||
|
||||
threads[i] = kthread_create((void *)stop_cpu, smdata, "kstop%u",
|
||||
i);
|
||||
if (IS_ERR(threads[i])) {
|
||||
err = PTR_ERR(threads[i]);
|
||||
threads[i] = NULL;
|
||||
goto kill_threads;
|
||||
}
|
||||
|
||||
/* Place it onto correct cpu. */
|
||||
kthread_bind(threads[i], i);
|
||||
|
||||
/* Make it highest prio. */
|
||||
if (sched_setscheduler_nocheck(threads[i], SCHED_FIFO, ¶m))
|
||||
BUG();
|
||||
}
|
||||
|
||||
/* We've created all the threads. Wake them all: hold this CPU so one
|
||||
* doesn't hit this CPU until we're ready. */
|
||||
get_cpu();
|
||||
for_each_online_cpu(i)
|
||||
wake_up_process(threads[i]);
|
||||
|
||||
/* This will release the thread on our CPU. */
|
||||
put_cpu();
|
||||
wait_for_completion(&finished);
|
||||
mutex_unlock(&lock);
|
||||
|
||||
kfree(threads);
|
||||
|
||||
return active.fnret;
|
||||
|
||||
kill_threads:
|
||||
for_each_online_cpu(i)
|
||||
if (threads[i])
|
||||
kthread_stop(threads[i]);
|
||||
mutex_unlock(&lock);
|
||||
|
||||
kfree(threads);
|
||||
return err;
|
||||
}
|
||||
|
||||
int stop_machine_run(int (*fn)(void *), void *data, unsigned int cpu)
|
||||
int stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus)
|
||||
{
|
||||
struct task_struct *p;
|
||||
int ret;
|
||||
|
||||
/* No CPUs can come up or down during this. */
|
||||
get_online_cpus();
|
||||
p = __stop_machine_run(fn, data, cpu);
|
||||
if (!IS_ERR(p))
|
||||
ret = kthread_stop(p);
|
||||
else
|
||||
ret = PTR_ERR(p);
|
||||
ret = __stop_machine(fn, data, cpus);
|
||||
put_online_cpus();
|
||||
|
||||
return ret;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(stop_machine_run);
|
||||
EXPORT_SYMBOL_GPL(stop_machine);
|
||||
|
|
|
@ -587,7 +587,7 @@ static int __ftrace_modify_code(void *data)
|
|||
|
||||
static void ftrace_run_update_code(int command)
|
||||
{
|
||||
stop_machine_run(__ftrace_modify_code, &command, NR_CPUS);
|
||||
stop_machine(__ftrace_modify_code, &command, NULL);
|
||||
}
|
||||
|
||||
void ftrace_disable_daemon(void)
|
||||
|
@ -787,7 +787,7 @@ static int ftrace_update_code(void)
|
|||
!ftrace_enabled || !ftraced_trigger)
|
||||
return 0;
|
||||
|
||||
stop_machine_run(__ftrace_update_code, NULL, NR_CPUS);
|
||||
stop_machine(__ftrace_update_code, NULL, NULL);
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
@ -1564,7 +1564,7 @@ static int __init ftrace_dynamic_init(void)
|
|||
|
||||
addr = (unsigned long)ftrace_record_ip;
|
||||
|
||||
stop_machine_run(ftrace_dyn_arch_init, &addr, NR_CPUS);
|
||||
stop_machine(ftrace_dyn_arch_init, &addr, NULL);
|
||||
|
||||
/* ftrace_dyn_arch_init places the return code in addr */
|
||||
if (addr) {
|
||||
|
|
|
@ -2372,7 +2372,7 @@ static void build_zonelist_cache(pg_data_t *pgdat)
|
|||
|
||||
#endif /* CONFIG_NUMA */
|
||||
|
||||
/* return values int ....just for stop_machine_run() */
|
||||
/* return values int ....just for stop_machine() */
|
||||
static int __build_all_zonelists(void *dummy)
|
||||
{
|
||||
int nid;
|
||||
|
@ -2397,7 +2397,7 @@ void build_all_zonelists(void)
|
|||
} else {
|
||||
/* we have to stop all cpus to guarantee there is no user
|
||||
of zonelist */
|
||||
stop_machine_run(__build_all_zonelists, NULL, NR_CPUS);
|
||||
stop_machine(__build_all_zonelists, NULL, NULL);
|
||||
/* cpuset refresh routine should be here */
|
||||
}
|
||||
vm_total_pages = nr_free_pagecache_pages();
|
||||
|
|
Loading…
Reference in New Issue