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-rw-r--r--lib/Kconfig.debug9
-rw-r--r--lib/Makefile1
-rw-r--r--lib/kernel_lock.c143
3 files changed, 0 insertions, 153 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 2b97418c67e2..6f440d82b58d 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -470,15 +470,6 @@ config DEBUG_MUTEXES
470 This feature allows mutex semantics violations to be detected and 470 This feature allows mutex semantics violations to be detected and
471 reported. 471 reported.
472 472
473config BKL
474 bool "Big Kernel Lock" if (SMP || PREEMPT)
475 default y
476 help
477 This is the traditional lock that is used in old code instead
478 of proper locking. All drivers that use the BKL should depend
479 on this symbol.
480 Say Y here unless you are working on removing the BKL.
481
482config DEBUG_LOCK_ALLOC 473config DEBUG_LOCK_ALLOC
483 bool "Lock debugging: detect incorrect freeing of live locks" 474 bool "Lock debugging: detect incorrect freeing of live locks"
484 depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT 475 depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT
diff --git a/lib/Makefile b/lib/Makefile
index b73ba01a818a..ef7ed71a6ffd 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -43,7 +43,6 @@ obj-$(CONFIG_GENERIC_FIND_LAST_BIT) += find_last_bit.o
43CFLAGS_hweight.o = $(subst $(quote),,$(CONFIG_ARCH_HWEIGHT_CFLAGS)) 43CFLAGS_hweight.o = $(subst $(quote),,$(CONFIG_ARCH_HWEIGHT_CFLAGS))
44obj-$(CONFIG_GENERIC_HWEIGHT) += hweight.o 44obj-$(CONFIG_GENERIC_HWEIGHT) += hweight.o
45 45
46obj-$(CONFIG_LOCK_KERNEL) += kernel_lock.o
47obj-$(CONFIG_BTREE) += btree.o 46obj-$(CONFIG_BTREE) += btree.o
48obj-$(CONFIG_DEBUG_PREEMPT) += smp_processor_id.o 47obj-$(CONFIG_DEBUG_PREEMPT) += smp_processor_id.o
49obj-$(CONFIG_DEBUG_LIST) += list_debug.o 48obj-$(CONFIG_DEBUG_LIST) += list_debug.o
diff --git a/lib/kernel_lock.c b/lib/kernel_lock.c
deleted file mode 100644
index b135d04aa48a..000000000000
--- a/lib/kernel_lock.c
+++ /dev/null
@@ -1,143 +0,0 @@
1/*
2 * lib/kernel_lock.c
3 *
4 * This is the traditional BKL - big kernel lock. Largely
5 * relegated to obsolescence, but used by various less
6 * important (or lazy) subsystems.
7 */
8#include <linux/module.h>
9#include <linux/kallsyms.h>
10#include <linux/semaphore.h>
11#include <linux/smp_lock.h>
12
13#define CREATE_TRACE_POINTS
14#include <trace/events/bkl.h>
15
16/*
17 * The 'big kernel lock'
18 *
19 * This spinlock is taken and released recursively by lock_kernel()
20 * and unlock_kernel(). It is transparently dropped and reacquired
21 * over schedule(). It is used to protect legacy code that hasn't
22 * been migrated to a proper locking design yet.
23 *
24 * Don't use in new code.
25 */
26static __cacheline_aligned_in_smp DEFINE_RAW_SPINLOCK(kernel_flag);
27
28
29/*
30 * Acquire/release the underlying lock from the scheduler.
31 *
32 * This is called with preemption disabled, and should
33 * return an error value if it cannot get the lock and
34 * TIF_NEED_RESCHED gets set.
35 *
36 * If it successfully gets the lock, it should increment
37 * the preemption count like any spinlock does.
38 *
39 * (This works on UP too - do_raw_spin_trylock will never
40 * return false in that case)
41 */
42int __lockfunc __reacquire_kernel_lock(void)
43{
44 while (!do_raw_spin_trylock(&kernel_flag)) {
45 if (need_resched())
46 return -EAGAIN;
47 cpu_relax();
48 }
49 preempt_disable();
50 return 0;
51}
52
53void __lockfunc __release_kernel_lock(void)
54{
55 do_raw_spin_unlock(&kernel_flag);
56 preempt_enable_no_resched();
57}
58
59/*
60 * These are the BKL spinlocks - we try to be polite about preemption.
61 * If SMP is not on (ie UP preemption), this all goes away because the
62 * do_raw_spin_trylock() will always succeed.
63 */
64#ifdef CONFIG_PREEMPT
65static inline void __lock_kernel(void)
66{
67 preempt_disable();
68 if (unlikely(!do_raw_spin_trylock(&kernel_flag))) {
69 /*
70 * If preemption was disabled even before this
71 * was called, there's nothing we can be polite
72 * about - just spin.
73 */
74 if (preempt_count() > 1) {
75 do_raw_spin_lock(&kernel_flag);
76 return;
77 }
78
79 /*
80 * Otherwise, let's wait for the kernel lock
81 * with preemption enabled..
82 */
83 do {
84 preempt_enable();
85 while (raw_spin_is_locked(&kernel_flag))
86 cpu_relax();
87 preempt_disable();
88 } while (!do_raw_spin_trylock(&kernel_flag));
89 }
90}
91
92#else
93
94/*
95 * Non-preemption case - just get the spinlock
96 */
97static inline void __lock_kernel(void)
98{
99 do_raw_spin_lock(&kernel_flag);
100}
101#endif
102
103static inline void __unlock_kernel(void)
104{
105 /*
106 * the BKL is not covered by lockdep, so we open-code the
107 * unlocking sequence (and thus avoid the dep-chain ops):
108 */
109 do_raw_spin_unlock(&kernel_flag);
110 preempt_enable();
111}
112
113/*
114 * Getting the big kernel lock.
115 *
116 * This cannot happen asynchronously, so we only need to
117 * worry about other CPU's.
118 */
119void __lockfunc _lock_kernel(const char *func, const char *file, int line)
120{
121 int depth = current->lock_depth + 1;
122
123 trace_lock_kernel(func, file, line);
124
125 if (likely(!depth)) {
126 might_sleep();
127 __lock_kernel();
128 }
129 current->lock_depth = depth;
130}
131
132void __lockfunc _unlock_kernel(const char *func, const char *file, int line)
133{
134 BUG_ON(current->lock_depth < 0);
135 if (likely(--current->lock_depth < 0))
136 __unlock_kernel();
137
138 trace_unlock_kernel(func, file, line);
139}
140
141EXPORT_SYMBOL(_lock_kernel);
142EXPORT_SYMBOL(_unlock_kernel);
143
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-06 16:42:01 -0500