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authorIngo Molnar <mingo@kernel.org>2017-06-20 12:19:09 +0200
committerIngo Molnar <mingo@kernel.org>2017-06-20 12:19:09 +0200
commit5dd43ce2f69d42a71dcacdb13d17d8c0ac1fe8f7 (patch)
tree8fd9fc956274bf3b64b4ec736cdb38d9ba9bf6c3
parent4b1c480bfa3b246e292f4d50167756252a9717ed (diff)
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sched/wait: Split out the wait_bit*() APIs from <linux/wait.h> into <linux/wait_bit.h>
The wait_bit*() types and APIs are mixed into wait.h, but they are a pretty orthogonal extension of wait-queues. Furthermore, only about 50 kernel files use these APIs, while over 1000 use the regular wait-queue functionality. So clean up the main wait.h by moving the wait-bit functionality out of it, into a separate .h and .c file: include/linux/wait_bit.h for types and APIs kernel/sched/wait_bit.c for the implementation Update all header dependencies. This reduces the size of wait.h rather significantly, by about 30%. Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
-rw-r--r--fs/cachefiles/internal.h2
-rw-r--r--fs/cifs/inode.c1
-rw-r--r--fs/nfs/internal.h1
-rw-r--r--include/linux/fs.h2
-rw-r--r--include/linux/sunrpc/sched.h2
-rw-r--r--include/linux/wait.h250
-rw-r--r--include/linux/wait_bit.h260
-rw-r--r--kernel/sched/Makefile2
-rw-r--r--kernel/sched/wait.c257
-rw-r--r--kernel/sched/wait_bit.c263
-rw-r--r--security/keys/internal.h1
11 files changed, 530 insertions, 511 deletions
diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h
index 54a4fcd679ed..bb3a02ca9da4 100644
--- a/fs/cachefiles/internal.h
+++ b/fs/cachefiles/internal.h
@@ -18,7 +18,7 @@
#include <linux/fscache-cache.h>
#include <linux/timer.h>
-#include <linux/wait.h>
+#include <linux/wait_bit.h>
#include <linux/cred.h>
#include <linux/workqueue.h>
#include <linux/security.h>
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 4d1fcd76d022..a8693632235f 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -24,6 +24,7 @@
#include <linux/pagemap.h>
#include <linux/freezer.h>
#include <linux/sched/signal.h>
+#include <linux/wait_bit.h>
#include <asm/div64.h>
#include "cifsfs.h"
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 3e24392f2caa..8701d7617964 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -7,6 +7,7 @@
#include <linux/security.h>
#include <linux/crc32.h>
#include <linux/nfs_page.h>
+#include <linux/wait_bit.h>
#define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 803e5a9b2654..53f7e49d8fe5 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2,7 +2,7 @@
#define _LINUX_FS_H
#include <linux/linkage.h>
-#include <linux/wait.h>
+#include <linux/wait_bit.h>
#include <linux/kdev_t.h>
#include <linux/dcache.h>
#include <linux/path.h>
diff --git a/include/linux/sunrpc/sched.h b/include/linux/sunrpc/sched.h
index 7ba040c797ec..9d7529ffc4ce 100644
--- a/include/linux/sunrpc/sched.h
+++ b/include/linux/sunrpc/sched.h
@@ -13,7 +13,7 @@
#include <linux/ktime.h>
#include <linux/sunrpc/types.h>
#include <linux/spinlock.h>
-#include <linux/wait.h>
+#include <linux/wait_bit.h>
#include <linux/workqueue.h>
#include <linux/sunrpc/xdr.h>
diff --git a/include/linux/wait.h b/include/linux/wait.h
index 0805098f3589..629489746f8a 100644
--- a/include/linux/wait.h
+++ b/include/linux/wait.h
@@ -29,18 +29,6 @@ struct wait_queue_entry {
struct list_head task_list;
};
-struct wait_bit_key {
- void *flags;
- int bit_nr;
-#define WAIT_ATOMIC_T_BIT_NR -1
- unsigned long timeout;
-};
-
-struct wait_bit_queue_entry {
- struct wait_bit_key key;
- struct wait_queue_entry wq_entry;
-};
-
struct wait_queue_head {
spinlock_t lock;
struct list_head task_list;
@@ -68,12 +56,6 @@ struct task_struct;
#define DECLARE_WAIT_QUEUE_HEAD(name) \
struct wait_queue_head name = __WAIT_QUEUE_HEAD_INITIALIZER(name)
-#define __WAIT_BIT_KEY_INITIALIZER(word, bit) \
- { .flags = word, .bit_nr = bit, }
-
-#define __WAIT_ATOMIC_T_KEY_INITIALIZER(p) \
- { .flags = p, .bit_nr = WAIT_ATOMIC_T_BIT_NR, }
-
extern void __init_waitqueue_head(struct wait_queue_head *wq_head, const char *name, struct lock_class_key *);
#define init_waitqueue_head(wq_head) \
@@ -200,22 +182,11 @@ __remove_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq
list_del(&wq_entry->task_list);
}
-typedef int wait_bit_action_f(struct wait_bit_key *key, int mode);
void __wake_up(struct wait_queue_head *wq_head, unsigned int mode, int nr, void *key);
void __wake_up_locked_key(struct wait_queue_head *wq_head, unsigned int mode, void *key);
void __wake_up_sync_key(struct wait_queue_head *wq_head, unsigned int mode, int nr, void *key);
void __wake_up_locked(struct wait_queue_head *wq_head, unsigned int mode, int nr);
void __wake_up_sync(struct wait_queue_head *wq_head, unsigned int mode, int nr);
-void __wake_up_bit(struct wait_queue_head *wq_head, void *word, int bit);
-int __wait_on_bit(struct wait_queue_head *wq_head, struct wait_bit_queue_entry *wbq_entry, wait_bit_action_f *action, unsigned int mode);
-int __wait_on_bit_lock(struct wait_queue_head *wq_head, struct wait_bit_queue_entry *wbq_entry, wait_bit_action_f *action, unsigned int mode);
-void wake_up_bit(void *word, int bit);
-void wake_up_atomic_t(atomic_t *p);
-int out_of_line_wait_on_bit(void *word, int, wait_bit_action_f *action, unsigned int mode);
-int out_of_line_wait_on_bit_timeout(void *word, int, wait_bit_action_f *action, unsigned int mode, unsigned long timeout);
-int out_of_line_wait_on_bit_lock(void *word, int, wait_bit_action_f *action, unsigned int mode);
-int out_of_line_wait_on_atomic_t(atomic_t *p, int (*)(atomic_t *), unsigned int mode);
-struct wait_queue_head *bit_waitqueue(void *word, int bit);
#define wake_up(x) __wake_up(x, TASK_NORMAL, 1, NULL)
#define wake_up_nr(x, nr) __wake_up(x, TASK_NORMAL, nr, NULL)
@@ -976,7 +947,6 @@ void finish_wait(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_en
long wait_woken(struct wait_queue_entry *wq_entry, unsigned mode, long timeout);
int woken_wake_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync, void *key);
int autoremove_wake_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync, void *key);
-int wake_bit_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync, void *key);
#define DEFINE_WAIT_FUNC(name, function) \
struct wait_queue_entry name = { \
@@ -987,17 +957,6 @@ int wake_bit_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync
#define DEFINE_WAIT(name) DEFINE_WAIT_FUNC(name, autoremove_wake_function)
-#define DEFINE_WAIT_BIT(name, word, bit) \
- struct wait_bit_queue_entry name = { \
- .key = __WAIT_BIT_KEY_INITIALIZER(word, bit), \
- .wq_entry = { \
- .private = current, \
- .func = wake_bit_function, \
- .task_list = \
- LIST_HEAD_INIT((name).wq_entry.task_list), \
- }, \
- }
-
#define init_wait(wait) \
do { \
(wait)->private = current; \
@@ -1006,213 +965,4 @@ int wake_bit_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync
(wait)->flags = 0; \
} while (0)
-
-extern int bit_wait(struct wait_bit_key *key, int bit);
-extern int bit_wait_io(struct wait_bit_key *key, int bit);
-extern int bit_wait_timeout(struct wait_bit_key *key, int bit);
-extern int bit_wait_io_timeout(struct wait_bit_key *key, int bit);
-
-/**
- * wait_on_bit - wait for a bit to be cleared
- * @word: the word being waited on, a kernel virtual address
- * @bit: the bit of the word being waited on
- * @mode: the task state to sleep in
- *
- * There is a standard hashed waitqueue table for generic use. This
- * is the part of the hashtable's accessor API that waits on a bit.
- * For instance, if one were to have waiters on a bitflag, one would
- * call wait_on_bit() in threads waiting for the bit to clear.
- * One uses wait_on_bit() where one is waiting for the bit to clear,
- * but has no intention of setting it.
- * Returned value will be zero if the bit was cleared, or non-zero
- * if the process received a signal and the mode permitted wakeup
- * on that signal.
- */
-static inline int
-wait_on_bit(unsigned long *word, int bit, unsigned mode)
-{
- might_sleep();
- if (!test_bit(bit, word))
- return 0;
- return out_of_line_wait_on_bit(word, bit,
- bit_wait,
- mode);
-}
-
-/**
- * wait_on_bit_io - wait for a bit to be cleared
- * @word: the word being waited on, a kernel virtual address
- * @bit: the bit of the word being waited on
- * @mode: the task state to sleep in
- *
- * Use the standard hashed waitqueue table to wait for a bit
- * to be cleared. This is similar to wait_on_bit(), but calls
- * io_schedule() instead of schedule() for the actual waiting.
- *
- * Returned value will be zero if the bit was cleared, or non-zero
- * if the process received a signal and the mode permitted wakeup
- * on that signal.
- */
-static inline int
-wait_on_bit_io(unsigned long *word, int bit, unsigned mode)
-{
- might_sleep();
- if (!test_bit(bit, word))
- return 0;
- return out_of_line_wait_on_bit(word, bit,
- bit_wait_io,
- mode);
-}
-
-/**
- * wait_on_bit_timeout - wait for a bit to be cleared or a timeout elapses
- * @word: the word being waited on, a kernel virtual address
- * @bit: the bit of the word being waited on
- * @mode: the task state to sleep in
- * @timeout: timeout, in jiffies
- *
- * Use the standard hashed waitqueue table to wait for a bit
- * to be cleared. This is similar to wait_on_bit(), except also takes a
- * timeout parameter.
- *
- * Returned value will be zero if the bit was cleared before the
- * @timeout elapsed, or non-zero if the @timeout elapsed or process
- * received a signal and the mode permitted wakeup on that signal.
- */
-static inline int
-wait_on_bit_timeout(unsigned long *word, int bit, unsigned mode,
- unsigned long timeout)
-{
- might_sleep();
- if (!test_bit(bit, word))
- return 0;
- return out_of_line_wait_on_bit_timeout(word, bit,
- bit_wait_timeout,
- mode, timeout);
-}
-
-/**
- * wait_on_bit_action - wait for a bit to be cleared
- * @word: the word being waited on, a kernel virtual address
- * @bit: the bit of the word being waited on
- * @action: the function used to sleep, which may take special actions
- * @mode: the task state to sleep in
- *
- * Use the standard hashed waitqueue table to wait for a bit
- * to be cleared, and allow the waiting action to be specified.
- * This is like wait_on_bit() but allows fine control of how the waiting
- * is done.
- *
- * Returned value will be zero if the bit was cleared, or non-zero
- * if the process received a signal and the mode permitted wakeup
- * on that signal.
- */
-static inline int
-wait_on_bit_action(unsigned long *word, int bit, wait_bit_action_f *action,
- unsigned mode)
-{
- might_sleep();
- if (!test_bit(bit, word))
- return 0;
- return out_of_line_wait_on_bit(word, bit, action, mode);
-}
-
-/**
- * wait_on_bit_lock - wait for a bit to be cleared, when wanting to set it
- * @word: the word being waited on, a kernel virtual address
- * @bit: the bit of the word being waited on
- * @mode: the task state to sleep in
- *
- * There is a standard hashed waitqueue table for generic use. This
- * is the part of the hashtable's accessor API that waits on a bit
- * when one intends to set it, for instance, trying to lock bitflags.
- * For instance, if one were to have waiters trying to set bitflag
- * and waiting for it to clear before setting it, one would call
- * wait_on_bit() in threads waiting to be able to set the bit.
- * One uses wait_on_bit_lock() where one is waiting for the bit to
- * clear with the intention of setting it, and when done, clearing it.
- *
- * Returns zero if the bit was (eventually) found to be clear and was
- * set. Returns non-zero if a signal was delivered to the process and
- * the @mode allows that signal to wake the process.
- */
-static inline int
-wait_on_bit_lock(unsigned long *word, int bit, unsigned mode)
-{
- might_sleep();
- if (!test_and_set_bit(bit, word))
- return 0;
- return out_of_line_wait_on_bit_lock(word, bit, bit_wait, mode);
-}
-
-/**
- * wait_on_bit_lock_io - wait for a bit to be cleared, when wanting to set it
- * @word: the word being waited on, a kernel virtual address
- * @bit: the bit of the word being waited on
- * @mode: the task state to sleep in
- *
- * Use the standard hashed waitqueue table to wait for a bit
- * to be cleared and then to atomically set it. This is similar
- * to wait_on_bit(), but calls io_schedule() instead of schedule()
- * for the actual waiting.
- *
- * Returns zero if the bit was (eventually) found to be clear and was
- * set. Returns non-zero if a signal was delivered to the process and
- * the @mode allows that signal to wake the process.
- */
-static inline int
-wait_on_bit_lock_io(unsigned long *word, int bit, unsigned mode)
-{
- might_sleep();
- if (!test_and_set_bit(bit, word))
- return 0;
- return out_of_line_wait_on_bit_lock(word, bit, bit_wait_io, mode);
-}
-
-/**
- * wait_on_bit_lock_action - wait for a bit to be cleared, when wanting to set it
- * @word: the word being waited on, a kernel virtual address
- * @bit: the bit of the word being waited on
- * @action: the function used to sleep, which may take special actions
- * @mode: the task state to sleep in
- *
- * Use the standard hashed waitqueue table to wait for a bit
- * to be cleared and then to set it, and allow the waiting action
- * to be specified.
- * This is like wait_on_bit() but allows fine control of how the waiting
- * is done.
- *
- * Returns zero if the bit was (eventually) found to be clear and was
- * set. Returns non-zero if a signal was delivered to the process and
- * the @mode allows that signal to wake the process.
- */
-static inline int
-wait_on_bit_lock_action(unsigned long *word, int bit, wait_bit_action_f *action,
- unsigned mode)
-{
- might_sleep();
- if (!test_and_set_bit(bit, word))
- return 0;
- return out_of_line_wait_on_bit_lock(word, bit, action, mode);
-}
-
-/**
- * wait_on_atomic_t - Wait for an atomic_t to become 0
- * @val: The atomic value being waited on, a kernel virtual address
- * @action: the function used to sleep, which may take special actions
- * @mode: the task state to sleep in
- *
- * Wait for an atomic_t to become 0. We abuse the bit-wait waitqueue table for
- * the purpose of getting a waitqueue, but we set the key to a bit number
- * outside of the target 'word'.
- */
-static inline
-int wait_on_atomic_t(atomic_t *val, int (*action)(atomic_t *), unsigned mode)
-{
- might_sleep();
- if (atomic_read(val) == 0)
- return 0;
- return out_of_line_wait_on_atomic_t(val, action, mode);
-}
-
#endif /* _LINUX_WAIT_H */
diff --git a/include/linux/wait_bit.h b/include/linux/wait_bit.h
new file mode 100644
index 000000000000..8c85c52d94b6
--- /dev/null
+++ b/include/linux/wait_bit.h
@@ -0,0 +1,260 @@
+#ifndef _LINUX_WAIT_BIT_H
+#define _LINUX_WAIT_BIT_H
+
+/*
+ * Linux wait-bit related types and methods:
+ */
+#include <linux/wait.h>
+
+struct wait_bit_key {
+ void *flags;
+ int bit_nr;
+#define WAIT_ATOMIC_T_BIT_NR -1
+ unsigned long timeout;
+};
+
+struct wait_bit_queue_entry {
+ struct wait_bit_key key;
+ struct wait_queue_entry wq_entry;
+};
+
+#define __WAIT_BIT_KEY_INITIALIZER(word, bit) \
+ { .flags = word, .bit_nr = bit, }
+
+#define __WAIT_ATOMIC_T_KEY_INITIALIZER(p) \
+ { .flags = p, .bit_nr = WAIT_ATOMIC_T_BIT_NR, }
+
+typedef int wait_bit_action_f(struct wait_bit_key *key, int mode);
+void __wake_up_bit(struct wait_queue_head *wq_head, void *word, int bit);
+int __wait_on_bit(struct wait_queue_head *wq_head, struct wait_bit_queue_entry *wbq_entry, wait_bit_action_f *action, unsigned int mode);
+int __wait_on_bit_lock(struct wait_queue_head *wq_head, struct wait_bit_queue_entry *wbq_entry, wait_bit_action_f *action, unsigned int mode);
+void wake_up_bit(void *word, int bit);
+void wake_up_atomic_t(atomic_t *p);
+int out_of_line_wait_on_bit(void *word, int, wait_bit_action_f *action, unsigned int mode);
+int out_of_line_wait_on_bit_timeout(void *word, int, wait_bit_action_f *action, unsigned int mode, unsigned long timeout);
+int out_of_line_wait_on_bit_lock(void *word, int, wait_bit_action_f *action, unsigned int mode);
+int out_of_line_wait_on_atomic_t(atomic_t *p, int (*)(atomic_t *), unsigned int mode);
+struct wait_queue_head *bit_waitqueue(void *word, int bit);
+
+int wake_bit_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync, void *key);
+
+#define DEFINE_WAIT_BIT(name, word, bit) \
+ struct wait_bit_queue_entry name = { \
+ .key = __WAIT_BIT_KEY_INITIALIZER(word, bit), \
+ .wq_entry = { \
+ .private = current, \
+ .func = wake_bit_function, \
+ .task_list = \
+ LIST_HEAD_INIT((name).wq_entry.task_list), \
+ }, \
+ }
+
+extern int bit_wait(struct wait_bit_key *key, int bit);
+extern int bit_wait_io(struct wait_bit_key *key, int bit);
+extern int bit_wait_timeout(struct wait_bit_key *key, int bit);
+extern int bit_wait_io_timeout(struct wait_bit_key *key, int bit);
+
+/**
+ * wait_on_bit - wait for a bit to be cleared
+ * @word: the word being waited on, a kernel virtual address
+ * @bit: the bit of the word being waited on
+ * @mode: the task state to sleep in
+ *
+ * There is a standard hashed waitqueue table for generic use. This
+ * is the part of the hashtable's accessor API that waits on a bit.
+ * For instance, if one were to have waiters on a bitflag, one would
+ * call wait_on_bit() in threads waiting for the bit to clear.
+ * One uses wait_on_bit() where one is waiting for the bit to clear,
+ * but has no intention of setting it.
+ * Returned value will be zero if the bit was cleared, or non-zero
+ * if the process received a signal and the mode permitted wakeup
+ * on that signal.
+ */
+static inline int
+wait_on_bit(unsigned long *word, int bit, unsigned mode)
+{
+ might_sleep();
+ if (!test_bit(bit, word))
+ return 0;
+ return out_of_line_wait_on_bit(word, bit,
+ bit_wait,
+ mode);
+}
+
+/**
+ * wait_on_bit_io - wait for a bit to be cleared
+ * @word: the word being waited on, a kernel virtual address
+ * @bit: the bit of the word being waited on
+ * @mode: the task state to sleep in
+ *
+ * Use the standard hashed waitqueue table to wait for a bit
+ * to be cleared. This is similar to wait_on_bit(), but calls
+ * io_schedule() instead of schedule() for the actual waiting.
+ *
+ * Returned value will be zero if the bit was cleared, or non-zero
+ * if the process received a signal and the mode permitted wakeup
+ * on that signal.
+ */
+static inline int
+wait_on_bit_io(unsigned long *word, int bit, unsigned mode)
+{
+ might_sleep();
+ if (!test_bit(bit, word))
+ return 0;
+ return out_of_line_wait_on_bit(word, bit,
+ bit_wait_io,
+ mode);
+}
+
+/**
+ * wait_on_bit_timeout - wait for a bit to be cleared or a timeout elapses
+ * @word: the word being waited on, a kernel virtual address
+ * @bit: the bit of the word being waited on
+ * @mode: the task state to sleep in
+ * @timeout: timeout, in jiffies
+ *
+ * Use the standard hashed waitqueue table to wait for a bit
+ * to be cleared. This is similar to wait_on_bit(), except also takes a
+ * timeout parameter.
+ *
+ * Returned value will be zero if the bit was cleared before the
+ * @timeout elapsed, or non-zero if the @timeout elapsed or process
+ * received a signal and the mode permitted wakeup on that signal.
+ */
+static inline int
+wait_on_bit_timeout(unsigned long *word, int bit, unsigned mode,
+ unsigned long timeout)
+{
+ might_sleep();
+ if (!test_bit(bit, word))
+ return 0;
+ return out_of_line_wait_on_bit_timeout(word, bit,
+ bit_wait_timeout,
+ mode, timeout);
+}
+
+/**
+ * wait_on_bit_action - wait for a bit to be cleared
+ * @word: the word being waited on, a kernel virtual address
+ * @bit: the bit of the word being waited on
+ * @action: the function used to sleep, which may take special actions
+ * @mode: the task state to sleep in
+ *
+ * Use the standard hashed waitqueue table to wait for a bit
+ * to be cleared, and allow the waiting action to be specified.
+ * This is like wait_on_bit() but allows fine control of how the waiting
+ * is done.
+ *
+ * Returned value will be zero if the bit was cleared, or non-zero
+ * if the process received a signal and the mode permitted wakeup
+ * on that signal.
+ */
+static inline int
+wait_on_bit_action(unsigned long *word, int bit, wait_bit_action_f *action,
+ unsigned mode)
+{
+ might_sleep();
+ if (!test_bit(bit, word))
+ return 0;
+ return out_of_line_wait_on_bit(word, bit, action, mode);
+}
+
+/**
+ * wait_on_bit_lock - wait for a bit to be cleared, when wanting to set it
+ * @word: the word being waited on, a kernel virtual address
+ * @bit: the bit of the word being waited on
+ * @mode: the task state to sleep in
+ *
+ * There is a standard hashed waitqueue table for generic use. This
+ * is the part of the hashtable's accessor API that waits on a bit
+ * when one intends to set it, for instance, trying to lock bitflags.
+ * For instance, if one were to have waiters trying to set bitflag
+ * and waiting for it to clear before setting it, one would call
+ * wait_on_bit() in threads waiting to be able to set the bit.
+ * One uses wait_on_bit_lock() where one is waiting for the bit to
+ * clear with the intention of setting it, and when done, clearing it.
+ *
+ * Returns zero if the bit was (eventually) found to be clear and was
+ * set. Returns non-zero if a signal was delivered to the process and
+ * the @mode allows that signal to wake the process.
+ */
+static inline int
+wait_on_bit_lock(unsigned long *word, int bit, unsigned mode)
+{
+ might_sleep();
+ if (!test_and_set_bit(bit, word))
+ return 0;
+ return out_of_line_wait_on_bit_lock(word, bit, bit_wait, mode);
+}
+
+/**
+ * wait_on_bit_lock_io - wait for a bit to be cleared, when wanting to set it
+ * @word: the word being waited on, a kernel virtual address
+ * @bit: the bit of the word being waited on
+ * @mode: the task state to sleep in
+ *
+ * Use the standard hashed waitqueue table to wait for a bit
+ * to be cleared and then to atomically set it. This is similar
+ * to wait_on_bit(), but calls io_schedule() instead of schedule()
+ * for the actual waiting.
+ *
+ * Returns zero if the bit was (eventually) found to be clear and was
+ * set. Returns non-zero if a signal was delivered to the process and
+ * the @mode allows that signal to wake the process.
+ */
+static inline int
+wait_on_bit_lock_io(unsigned long *word, int bit, unsigned mode)
+{
+ might_sleep();
+ if (!test_and_set_bit(bit, word))
+ return 0;
+ return out_of_line_wait_on_bit_lock(word, bit, bit_wait_io, mode);
+}
+
+/**
+ * wait_on_bit_lock_action - wait for a bit to be cleared, when wanting to set it
+ * @word: the word being waited on, a kernel virtual address
+ * @bit: the bit of the word being waited on
+ * @action: the function used to sleep, which may take special actions
+ * @mode: the task state to sleep in
+ *
+ * Use the standard hashed waitqueue table to wait for a bit
+ * to be cleared and then to set it, and allow the waiting action
+ * to be specified.
+ * This is like wait_on_bit() but allows fine control of how the waiting
+ * is done.
+ *
+ * Returns zero if the bit was (eventually) found to be clear and was
+ * set. Returns non-zero if a signal was delivered to the process and
+ * the @mode allows that signal to wake the process.
+ */
+static inline int
+wait_on_bit_lock_action(unsigned long *word, int bit, wait_bit_action_f *action,
+ unsigned mode)
+{
+ might_sleep();
+ if (!test_and_set_bit(bit, word))
+ return 0;
+ return out_of_line_wait_on_bit_lock(word, bit, action, mode);
+}
+
+/**
+ * wait_on_atomic_t - Wait for an atomic_t to become 0
+ * @val: The atomic value being waited on, a kernel virtual address
+ * @action: the function used to sleep, which may take special actions
+ * @mode: the task state to sleep in
+ *
+ * Wait for an atomic_t to become 0. We abuse the bit-wait waitqueue table for
+ * the purpose of getting a waitqueue, but we set the key to a bit number
+ * outside of the target 'word'.
+ */
+static inline
+int wait_on_atomic_t(atomic_t *val, int (*action)(atomic_t *), unsigned mode)
+{
+ might_sleep();
+ if (atomic_read(val) == 0)
+ return 0;
+ return out_of_line_wait_on_atomic_t(val, action, mode);
+}
+
+#endif /* _LINUX_WAIT_BIT_H */
diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile
index 89ab6758667b..16277e2ed8ee 100644
--- a/kernel/sched/Makefile
+++ b/kernel/sched/Makefile
@@ -17,7 +17,7 @@ endif
obj-y += core.o loadavg.o clock.o cputime.o
obj-y += idle_task.o fair.o rt.o deadline.o stop_task.o
-obj-y += wait.o swait.o completion.o idle.o
+obj-y += wait.o wait_bit.o swait.o completion.o idle.o
obj-$(CONFIG_SMP) += cpupri.o cpudeadline.o topology.o
obj-$(CONFIG_SCHED_AUTOGROUP) += autogroup.o
obj-$(CONFIG_SCHEDSTATS) += stats.o
diff --git a/kernel/sched/wait.c b/kernel/sched/wait.c
index 95e6d3820cba..6bcd7c3c4501 100644
--- a/kernel/sched/wait.c
+++ b/kernel/sched/wait.c
@@ -390,260 +390,3 @@ int woken_wake_function(struct wait_queue_entry *wq_entry, unsigned mode, int sy
return default_wake_function(wq_entry, mode, sync, key);
}
EXPORT_SYMBOL(woken_wake_function);
-
-int wake_bit_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync, void *arg)
-{
- struct wait_bit_key *key = arg;
- struct wait_bit_queue_entry *wait_bit = container_of(wq_entry, struct wait_bit_queue_entry, wq_entry);
-
- if (wait_bit->key.flags != key->flags ||
- wait_bit->key.bit_nr != key->bit_nr ||
- test_bit(key->bit_nr, key->flags))
- return 0;
- else
- return autoremove_wake_function(wq_entry, mode, sync, key);
-}
-EXPORT_SYMBOL(wake_bit_function);
-
-/*
- * To allow interruptible waiting and asynchronous (i.e. nonblocking)
- * waiting, the actions of __wait_on_bit() and __wait_on_bit_lock() are
- * permitted return codes. Nonzero return codes halt waiting and return.
- */
-int __sched
-__wait_on_bit(struct wait_queue_head *wq_head, struct wait_bit_queue_entry *wbq_entry,
- wait_bit_action_f *action, unsigned mode)
-{
- int ret = 0;
-
- do {
- prepare_to_wait(wq_head, &wbq_entry->wq_entry, mode);
- if (test_bit(wbq_entry->key.bit_nr, wbq_entry->key.flags))
- ret = (*action)(&wbq_entry->key, mode);
- } while (test_bit(wbq_entry->key.bit_nr, wbq_entry->key.flags) && !ret);
- finish_wait(wq_head, &wbq_entry->wq_entry);
- return ret;
-}
-EXPORT_SYMBOL(__wait_on_bit);
-
-int __sched out_of_line_wait_on_bit(void *word, int bit,
- wait_bit_action_f *action, unsigned mode)
-{
- struct wait_queue_head *wq_head = bit_waitqueue(word, bit);
- DEFINE_WAIT_BIT(wq_entry, word, bit);
-
- return __wait_on_bit(wq_head, &wq_entry, action, mode);
-}
-EXPORT_SYMBOL(out_of_line_wait_on_bit);
-
-int __sched out_of_line_wait_on_bit_timeout(
- void *word, int bit, wait_bit_action_f *action,
- unsigned mode, unsigned long timeout)
-{
- struct wait_queue_head *wq_head = bit_waitqueue(word, bit);
- DEFINE_WAIT_BIT(wq_entry, word, bit);
-
- wq_entry.key.timeout = jiffies + timeout;
- return __wait_on_bit(wq_head, &wq_entry, action, mode);
-}
-EXPORT_SYMBOL_GPL(out_of_line_wait_on_bit_timeout);
-
-int __sched
-__wait_on_bit_lock(struct wait_queue_head *wq_head, struct wait_bit_queue_entry *wbq_entry,
- wait_bit_action_f *action, unsigned mode)
-{
- int ret = 0;
-
- for (;;) {
- prepare_to_wait_exclusive(wq_head, &wbq_entry->wq_entry, mode);
- if (test_bit(wbq_entry->key.bit_nr, wbq_entry->key.flags)) {
- ret = action(&wbq_entry->key, mode);
- /*
- * See the comment in prepare_to_wait_event().
- * finish_wait() does not necessarily takes wwq_head->lock,
- * but test_and_set_bit() implies mb() which pairs with
- * smp_mb__after_atomic() before wake_up_page().
- */
- if (ret)
- finish_wait(wq_head, &wbq_entry->wq_entry);
- }
- if (!test_and_set_bit(wbq_entry->key.bit_nr, wbq_entry->key.flags)) {
- if (!ret)
- finish_wait(wq_head, &wbq_entry->wq_entry);
- return 0;
- } else if (ret) {
- return ret;
- }
- }
-}
-EXPORT_SYMBOL(__wait_on_bit_lock);
-
-int __sched out_of_line_wait_on_bit_lock(void *word, int bit,
- wait_bit_action_f *action, unsigned mode)
-{
- struct wait_queue_head *wq_head = bit_waitqueue(word, bit);
- DEFINE_WAIT_BIT(wq_entry, word, bit);
-
- return __wait_on_bit_lock(wq_head, &wq_entry, action, mode);
-}
-EXPORT_SYMBOL(out_of_line_wait_on_bit_lock);
-
-void __wake_up_bit(struct wait_queue_head *wq_head, void *word, int bit)
-{
- struct wait_bit_key key = __WAIT_BIT_KEY_INITIALIZER(word, bit);
- if (waitqueue_active(wq_head))
- __wake_up(wq_head, TASK_NORMAL, 1, &key);
-}
-EXPORT_SYMBOL(__wake_up_bit);
-
-/**
- * wake_up_bit - wake up a waiter on a bit
- * @word: the word being waited on, a kernel virtual address
- * @bit: the bit of the word being waited on
- *
- * There is a standard hashed waitqueue table for generic use. This
- * is the part of the hashtable's accessor API that wakes up waiters
- * on a bit. For instance, if one were to have waiters on a bitflag,
- * one would call wake_up_bit() after clearing the bit.
- *
- * In order for this to function properly, as it uses waitqueue_active()
- * internally, some kind of memory barrier must be done prior to calling
- * this. Typically, this will be smp_mb__after_atomic(), but in some
- * cases where bitflags are manipulated non-atomically under a lock, one
- * may need to use a less regular barrier, such fs/inode.c's smp_mb(),
- * because spin_unlock() does not guarantee a memory barrier.
- */
-void wake_up_bit(void *word, int bit)
-{
- __wake_up_bit(bit_waitqueue(word, bit), word, bit);
-}
-EXPORT_SYMBOL(wake_up_bit);
-
-/*
- * Manipulate the atomic_t address to produce a better bit waitqueue table hash
- * index (we're keying off bit -1, but that would produce a horrible hash
- * value).
- */
-static inline wait_queue_head_t *atomic_t_waitqueue(atomic_t *p)
-{
- if (BITS_PER_LONG == 64) {
- unsigned long q = (unsigned long)p;
- return bit_waitqueue((void *)(q & ~1), q & 1);
- }
- return bit_waitqueue(p, 0);
-}
-
-static int wake_atomic_t_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync,
- void *arg)
-{
- struct wait_bit_key *key = arg;
- struct wait_bit_queue_entry *wait_bit = container_of(wq_entry, struct wait_bit_queue_entry, wq_entry);
- atomic_t *val = key->flags;
-
- if (wait_bit->key.flags != key->flags ||
- wait_bit->key.bit_nr != key->bit_nr ||
- atomic_read(val) != 0)
- return 0;
- return autoremove_wake_function(wq_entry, mode, sync, key);
-}
-
-/*
- * To allow interruptible waiting and asynchronous (i.e. nonblocking) waiting,
- * the actions of __wait_on_atomic_t() are permitted return codes. Nonzero
- * return codes halt waiting and return.
- */
-static __sched
-int __wait_on_atomic_t(struct wait_queue_head *wq_head, struct wait_bit_queue_entry *wbq_entry,
- int (*action)(atomic_t *), unsigned mode)
-{
- atomic_t *val;
- int ret = 0;
-
- do {
- prepare_to_wait(wq_head, &wbq_entry->wq_entry, mode);
- val = wbq_entry->key.flags;
- if (atomic_read(val) == 0)
- break;
- ret = (*action)(val);
- } while (!ret && atomic_read(val) != 0);
- finish_wait(wq_head, &wbq_entry->wq_entry);
- return ret;
-}
-
-#define DEFINE_WAIT_ATOMIC_T(name, p) \
- struct wait_bit_queue_entry name = { \
- .key = __WAIT_ATOMIC_T_KEY_INITIALIZER(p), \
- .wq_entry = { \
- .private = current, \
- .func = wake_atomic_t_function, \
- .task_list = \
- LIST_HEAD_INIT((name).wq_entry.task_list), \
- }, \
- }
-
-__sched int out_of_line_wait_on_atomic_t(atomic_t *p, int (*action)(atomic_t *),
- unsigned mode)
-{
- struct wait_queue_head *wq_head = atomic_t_waitqueue(p);
- DEFINE_WAIT_ATOMIC_T(wq_entry, p);
-
- return __wait_on_atomic_t(wq_head, &wq_entry, action, mode);
-}
-EXPORT_SYMBOL(out_of_line_wait_on_atomic_t);
-
-/**
- * wake_up_atomic_t - Wake up a waiter on a atomic_t
- * @p: The atomic_t being waited on, a kernel virtual address
- *
- * Wake up anyone waiting for the atomic_t to go to zero.
- *
- * Abuse the bit-waker function and its waitqueue hash table set (the atomic_t
- * check is done by the waiter's wake function, not the by the waker itself).
- */
-void wake_up_atomic_t(atomic_t *p)
-{
- __wake_up_bit(atomic_t_waitqueue(p), p, WAIT_ATOMIC_T_BIT_NR);
-}
-EXPORT_SYMBOL(wake_up_atomic_t);
-
-__sched int bit_wait(struct wait_bit_key *word, int mode)
-{
- schedule();
- if (signal_pending_state(mode, current))
- return -EINTR;
- return 0;
-}
-EXPORT_SYMBOL(bit_wait);
-
-__sched int bit_wait_io(struct wait_bit_key *word, int mode)
-{
- io_schedule();
- if (signal_pending_state(mode, current))
- return -EINTR;
- return 0;
-}
-EXPORT_SYMBOL(bit_wait_io);
-
-__sched int bit_wait_timeout(struct wait_bit_key *word, int mode)
-{
- unsigned long now = READ_ONCE(jiffies);
- if (time_after_eq(now, word->timeout))
- return -EAGAIN;
- schedule_timeout(word->timeout - now);
- if (signal_pending_state(mode, current))
- return -EINTR;
- return 0;
-}
-EXPORT_SYMBOL_GPL(bit_wait_timeout);
-
-__sched int bit_wait_io_timeout(struct wait_bit_key *word, int mode)
-{
- unsigned long now = READ_ONCE(jiffies);
- if (time_after_eq(now, word->timeout))
- return -EAGAIN;
- io_schedule_timeout(word->timeout - now);
- if (signal_pending_state(mode, current))
- return -EINTR;
- return 0;
-}
-EXPORT_SYMBOL_GPL(bit_wait_io_timeout);
diff --git a/kernel/sched/wait_bit.c b/kernel/sched/wait_bit.c
new file mode 100644
index 000000000000..463bac84dfd1
--- /dev/null
+++ b/kernel/sched/wait_bit.c
@@ -0,0 +1,263 @@
+/*
+ * The implementation of the wait_bit*() and related waiting APIs:
+ */
+#include <linux/wait_bit.h>
+#include <linux/sched/signal.h>
+#include <linux/sched/debug.h>
+
+int wake_bit_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync, void *arg)
+{
+ struct wait_bit_key *key = arg;
+ struct wait_bit_queue_entry *wait_bit = container_of(wq_entry, struct wait_bit_queue_entry, wq_entry);
+
+ if (wait_bit->key.flags != key->flags ||
+ wait_bit->key.bit_nr != key->bit_nr ||
+ test_bit(key->bit_nr, key->flags))
+ return 0;
+ else
+ return autoremove_wake_function(wq_entry, mode, sync, key);
+}
+EXPORT_SYMBOL(wake_bit_function);
+
+/*
+ * To allow interruptible waiting and asynchronous (i.e. nonblocking)
+ * waiting, the actions of __wait_on_bit() and __wait_on_bit_lock() are
+ * permitted return codes. Nonzero return codes halt waiting and return.
+ */
+int __sched
+__wait_on_bit(struct wait_queue_head *wq_head, struct wait_bit_queue_entry *wbq_entry,
+ wait_bit_action_f *action, unsigned mode)
+{
+ int ret = 0;
+
+ do {
+ prepare_to_wait(wq_head, &wbq_entry->wq_entry, mode);
+ if (test_bit(wbq_entry->key.bit_nr, wbq_entry->key.flags))
+ ret = (*action)(&wbq_entry->key, mode);
+ } while (test_bit(wbq_entry->key.bit_nr, wbq_entry->key.flags) && !ret);
+ finish_wait(wq_head, &wbq_entry->wq_entry);
+ return ret;
+}
+EXPORT_SYMBOL(__wait_on_bit);
+
+int __sched out_of_line_wait_on_bit(void *word, int bit,
+ wait_bit_action_f *action, unsigned mode)
+{
+ struct wait_queue_head *wq_head = bit_waitqueue(word, bit);
+ DEFINE_WAIT_BIT(wq_entry, word, bit);
+
+ return __wait_on_bit(wq_head, &wq_entry, action, mode);
+}
+EXPORT_SYMBOL(out_of_line_wait_on_bit);
+
+int __sched out_of_line_wait_on_bit_timeout(
+ void *word, int bit, wait_bit_action_f *action,
+ unsigned mode, unsigned long timeout)
+{
+ struct wait_queue_head *wq_head = bit_waitqueue(word, bit);
+ DEFINE_WAIT_BIT(wq_entry, word, bit);
+
+ wq_entry.key.timeout = jiffies + timeout;
+ return __wait_on_bit(wq_head, &wq_entry, action, mode);
+}
+EXPORT_SYMBOL_GPL(out_of_line_wait_on_bit_timeout);
+
+int __sched
+__wait_on_bit_lock(struct wait_queue_head *wq_head, struct wait_bit_queue_entry *wbq_entry,
+ wait_bit_action_f *action, unsigned mode)
+{
+ int ret = 0;
+
+ for (;;) {
+ prepare_to_wait_exclusive(wq_head, &wbq_entry->wq_entry, mode);
+ if (test_bit(wbq_entry->key.bit_nr, wbq_entry->key.flags)) {
+ ret = action(&wbq_entry->key, mode);
+ /*
+ * See the comment in prepare_to_wait_event().
+ * finish_wait() does not necessarily takes wwq_head->lock,
+ * but test_and_set_bit() implies mb() which pairs with
+ * smp_mb__after_atomic() before wake_up_page().
+ */
+ if (ret)
+ finish_wait(wq_head, &wbq_entry->wq_entry);
+ }
+ if (!test_and_set_bit(wbq_entry->key.bit_nr, wbq_entry->key.flags)) {
+ if (!ret)
+ finish_wait(wq_head, &wbq_entry->wq_entry);
+ return 0;
+ } else if (ret) {
+ return ret;
+ }
+ }
+}
+EXPORT_SYMBOL(__wait_on_bit_lock);
+
+int __sched out_of_line_wait_on_bit_lock(void *word, int bit,
+ wait_bit_action_f *action, unsigned mode)
+{
+ struct wait_queue_head *wq_head = bit_waitqueue(word, bit);
+ DEFINE_WAIT_BIT(wq_entry, word, bit);
+
+ return __wait_on_bit_lock(wq_head, &wq_entry, action, mode);
+}
+EXPORT_SYMBOL(out_of_line_wait_on_bit_lock);
+
+void __wake_up_bit(struct wait_queue_head *wq_head, void *word, int bit)
+{
+ struct wait_bit_key key = __WAIT_BIT_KEY_INITIALIZER(word, bit);
+ if (waitqueue_active(wq_head))
+ __wake_up(wq_head, TASK_NORMAL, 1, &key);
+}
+EXPORT_SYMBOL(__wake_up_bit);
+
+/**
+ * wake_up_bit - wake up a waiter on a bit
+ * @word: the word being waited on, a kernel virtual address
+ * @bit: the bit of the word being waited on
+ *
+ * There is a standard hashed waitqueue table for generic use. This
+ * is the part of the hashtable's accessor API that wakes up waiters
+ * on a bit. For instance, if one were to have waiters on a bitflag,
+ * one would call wake_up_bit() after clearing the bit.
+ *
+ * In order for this to function properly, as it uses waitqueue_active()
+ * internally, some kind of memory barrier must be done prior to calling
+ * this. Typically, this will be smp_mb__after_atomic(), but in some
+ * cases where bitflags are manipulated non-atomically under a lock, one
+ * may need to use a less regular barrier, such fs/inode.c's smp_mb(),
+ * because spin_unlock() does not guarantee a memory barrier.
+ */
+void wake_up_bit(void *word, int bit)
+{
+ __wake_up_bit(bit_waitqueue(word, bit), word, bit);
+}
+EXPORT_SYMBOL(wake_up_bit);
+
+/*
+ * Manipulate the atomic_t address to produce a better bit waitqueue table hash
+ * index (we're keying off bit -1, but that would produce a horrible hash
+ * value).
+ */
+static inline wait_queue_head_t *atomic_t_waitqueue(atomic_t *p)
+{
+ if (BITS_PER_LONG == 64) {
+ unsigned long q = (unsigned long)p;
+ return bit_waitqueue((void *)(q & ~1), q & 1);
+ }
+ return bit_waitqueue(p, 0);
+}
+
+static int wake_atomic_t_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync,
+ void *arg)
+{
+ struct wait_bit_key *key = arg;
+ struct wait_bit_queue_entry *wait_bit = container_of(wq_entry, struct wait_bit_queue_entry, wq_entry);
+ atomic_t *val = key->flags;
+
+ if (wait_bit->key.flags != key->flags ||
+ wait_bit->key.bit_nr != key->bit_nr ||
+ atomic_read(val) != 0)
+ return 0;
+ return autoremove_wake_function(wq_entry, mode, sync, key);
+}
+
+/*
+ * To allow interruptible waiting and asynchronous (i.e. nonblocking) waiting,
+ * the actions of __wait_on_atomic_t() are permitted return codes. Nonzero
+ * return codes halt waiting and return.
+ */
+static __sched
+int __wait_on_atomic_t(struct wait_queue_head *wq_head, struct wait_bit_queue_entry *wbq_entry,
+ int (*action)(atomic_t *), unsigned mode)
+{
+ atomic_t *val;
+ int ret = 0;
+
+ do {
+ prepare_to_wait(wq_head, &wbq_entry->wq_entry, mode);
+ val = wbq_entry->key.flags;
+ if (atomic_read(val) == 0)
+ break;
+ ret = (*action)(val);
+ } while (!ret && atomic_read(val) != 0);
+ finish_wait(wq_head, &wbq_entry->wq_entry);
+ return ret;
+}
+
+#define DEFINE_WAIT_ATOMIC_T(name, p) \
+ struct wait_bit_queue_entry name = { \
+ .key = __WAIT_ATOMIC_T_KEY_INITIALIZER(p), \
+ .wq_entry = { \
+ .private = current, \
+ .func = wake_atomic_t_function, \
+ .task_list = \
+ LIST_HEAD_INIT((name).wq_entry.task_list), \
+ }, \
+ }
+
+__sched int out_of_line_wait_on_atomic_t(atomic_t *p, int (*action)(atomic_t *),
+ unsigned mode)
+{
+ struct wait_queue_head *wq_head = atomic_t_waitqueue(p);
+ DEFINE_WAIT_ATOMIC_T(wq_entry, p);
+
+ return __wait_on_atomic_t(wq_head, &wq_entry, action, mode);
+}
+EXPORT_SYMBOL(out_of_line_wait_on_atomic_t);
+
+/**
+ * wake_up_atomic_t - Wake up a waiter on a atomic_t
+ * @p: The atomic_t being waited on, a kernel virtual address
+ *
+ * Wake up anyone waiting for the atomic_t to go to zero.
+ *
+ * Abuse the bit-waker function and its waitqueue hash table set (the atomic_t
+ * check is done by the waiter's wake function, not the by the waker itself).
+ */
+void wake_up_atomic_t(atomic_t *p)
+{
+ __wake_up_bit(atomic_t_waitqueue(p), p, WAIT_ATOMIC_T_BIT_NR);
+}
+EXPORT_SYMBOL(wake_up_atomic_t);
+
+__sched int bit_wait(struct wait_bit_key *word, int mode)
+{
+ schedule();
+ if (signal_pending_state(mode, current))
+ return -EINTR;
+ return 0;
+}
+EXPORT_SYMBOL(bit_wait);
+
+__sched int bit_wait_io(struct wait_bit_key *word, int mode)
+{
+ io_schedule();
+ if (signal_pending_state(mode, current))
+ return -EINTR;
+ return 0;
+}
+EXPORT_SYMBOL(bit_wait_io);
+
+__sched int bit_wait_timeout(struct wait_bit_key *word, int mode)
+{
+ unsigned long now = READ_ONCE(jiffies);
+ if (time_after_eq(now, word->timeout))
+ return -EAGAIN;
+ schedule_timeout(word->timeout - now);
+ if (signal_pending_state(mode, current))
+ return -EINTR;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(bit_wait_timeout);
+
+__sched int bit_wait_io_timeout(struct wait_bit_key *word, int mode)
+{
+ unsigned long now = READ_ONCE(jiffies);
+ if (time_after_eq(now, word->timeout))
+ return -EAGAIN;
+ io_schedule_timeout(word->timeout - now);
+ if (signal_pending_state(mode, current))
+ return -EINTR;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(bit_wait_io_timeout);
diff --git a/security/keys/internal.h b/security/keys/internal.h
index c0f8682eba69..91bc6214ae57 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -13,6 +13,7 @@
#define _INTERNAL_H
#include <linux/sched.h>
+#include <linux/wait_bit.h>
#include <linux/cred.h>
#include <linux/key-type.h>
#include <linux/task_work.h>