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6
7#include <linux/export.h>
8#include <linux/kprobes.h>
9#include <linux/sched.h>
10
11notrace static nokprobe_inline
12unsigned int check_preemption_disabled(const char *what1, const char *what2)
13{
14 int this_cpu = raw_smp_processor_id();
15
16 if (likely(preempt_count()))
17 goto out;
18
19 if (irqs_disabled())
20 goto out;
21
22
23
24
25
26 if (cpumask_equal(current->cpus_ptr, cpumask_of(this_cpu)))
27 goto out;
28
29
30
31
32 if (system_state < SYSTEM_SCHEDULING)
33 goto out;
34
35
36
37
38 preempt_disable_notrace();
39
40 if (!printk_ratelimit())
41 goto out_enable;
42
43 printk(KERN_ERR "BUG: using %s%s() in preemptible [%08x] code: %s/%d\n",
44 what1, what2, preempt_count() - 1, current->comm, current->pid);
45
46 printk("caller is %pS\n", __builtin_return_address(0));
47 dump_stack();
48
49out_enable:
50 preempt_enable_no_resched_notrace();
51out:
52 return this_cpu;
53}
54
55notrace unsigned int debug_smp_processor_id(void)
56{
57 return check_preemption_disabled("smp_processor_id", "");
58}
59EXPORT_SYMBOL(debug_smp_processor_id);
60NOKPROBE_SYMBOL(debug_smp_processor_id);
61
62notrace void __this_cpu_preempt_check(const char *op)
63{
64 check_preemption_disabled("__this_cpu_", op);
65}
66EXPORT_SYMBOL(__this_cpu_preempt_check);
67NOKPROBE_SYMBOL(__this_cpu_preempt_check);
68