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-rw-r--r--lib/Makefile1
-rw-r--r--lib/kernel_lock.c55
-rw-r--r--lib/smp_processor_id.c55
3 files changed, 56 insertions, 55 deletions
diff --git a/lib/Makefile b/lib/Makefile
index 9eccea9429a7..5f10cb898407 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -20,6 +20,7 @@ lib-$(CONFIG_RWSEM_GENERIC_SPINLOCK) += rwsem-spinlock.o
20lib-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem.o 20lib-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem.o
21lib-$(CONFIG_GENERIC_FIND_NEXT_BIT) += find_next_bit.o 21lib-$(CONFIG_GENERIC_FIND_NEXT_BIT) += find_next_bit.o
22obj-$(CONFIG_LOCK_KERNEL) += kernel_lock.o 22obj-$(CONFIG_LOCK_KERNEL) += kernel_lock.o
23obj-$(CONFIG_DEBUG_PREEMPT) += smp_processor_id.o
23 24
24ifneq ($(CONFIG_HAVE_DEC_LOCK),y) 25ifneq ($(CONFIG_HAVE_DEC_LOCK),y)
25 lib-y += dec_and_lock.o 26 lib-y += dec_and_lock.o
diff --git a/lib/kernel_lock.c b/lib/kernel_lock.c
index 99b0ae3d51dd..bd2bc5d887b8 100644
--- a/lib/kernel_lock.c
+++ b/lib/kernel_lock.c
@@ -9,61 +9,6 @@
9#include <linux/module.h> 9#include <linux/module.h>
10#include <linux/kallsyms.h> 10#include <linux/kallsyms.h>
11 11
12#if defined(CONFIG_PREEMPT) && defined(__smp_processor_id) && \
13 defined(CONFIG_DEBUG_PREEMPT)
14
15/*
16 * Debugging check.
17 */
18unsigned int smp_processor_id(void)
19{
20 unsigned long preempt_count = preempt_count();
21 int this_cpu = __smp_processor_id();
22 cpumask_t this_mask;
23
24 if (likely(preempt_count))
25 goto out;
26
27 if (irqs_disabled())
28 goto out;
29
30 /*
31 * Kernel threads bound to a single CPU can safely use
32 * smp_processor_id():
33 */
34 this_mask = cpumask_of_cpu(this_cpu);
35
36 if (cpus_equal(current->cpus_allowed, this_mask))
37 goto out;
38
39 /*
40 * It is valid to assume CPU-locality during early bootup:
41 */
42 if (system_state != SYSTEM_RUNNING)
43 goto out;
44
45 /*
46 * Avoid recursion:
47 */
48 preempt_disable();
49
50 if (!printk_ratelimit())
51 goto out_enable;
52
53 printk(KERN_ERR "BUG: using smp_processor_id() in preemptible [%08x] code: %s/%d\n", preempt_count(), current->comm, current->pid);
54 print_symbol("caller is %s\n", (long)__builtin_return_address(0));
55 dump_stack();
56
57out_enable:
58 preempt_enable_no_resched();
59out:
60 return this_cpu;
61}
62
63EXPORT_SYMBOL(smp_processor_id);
64
65#endif /* PREEMPT && __smp_processor_id && DEBUG_PREEMPT */
66
67#ifdef CONFIG_PREEMPT_BKL 12#ifdef CONFIG_PREEMPT_BKL
68/* 13/*
69 * The 'big kernel semaphore' 14 * The 'big kernel semaphore'
diff --git a/lib/smp_processor_id.c b/lib/smp_processor_id.c
new file mode 100644
index 000000000000..42c08ef828c5
--- /dev/null
+++ b/lib/smp_processor_id.c
@@ -0,0 +1,55 @@
1/*
2 * lib/smp_processor_id.c
3 *
4 * DEBUG_PREEMPT variant of smp_processor_id().
5 */
6#include <linux/module.h>
7#include <linux/kallsyms.h>
8
9unsigned int debug_smp_processor_id(void)
10{
11 unsigned long preempt_count = preempt_count();
12 int this_cpu = raw_smp_processor_id();
13 cpumask_t this_mask;
14
15 if (likely(preempt_count))
16 goto out;
17
18 if (irqs_disabled())
19 goto out;
20
21 /*
22 * Kernel threads bound to a single CPU can safely use
23 * smp_processor_id():
24 */
25 this_mask = cpumask_of_cpu(this_cpu);
26
27 if (cpus_equal(current->cpus_allowed, this_mask))
28 goto out;
29
30 /*
31 * It is valid to assume CPU-locality during early bootup:
32 */
33 if (system_state != SYSTEM_RUNNING)
34 goto out;
35
36 /*
37 * Avoid recursion:
38 */
39 preempt_disable();
40
41 if (!printk_ratelimit())
42 goto out_enable;
43
44 printk(KERN_ERR "BUG: using smp_processor_id() in preemptible [%08x] code: %s/%d\n", preempt_count(), current->comm, current->pid);
45 print_symbol("caller is %s\n", (long)__builtin_return_address(0));
46 dump_stack();
47
48out_enable:
49 preempt_enable_no_resched();
50out:
51 return this_cpu;
52}
53
54EXPORT_SYMBOL(debug_smp_processor_id);
55