mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

staging: lustre: remove l_wait_event() and related code 

These macros are no longer used, so they can
be removed.

Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Patrick Farrell <paf@cray.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
NeilBrown 2018-02-13 10:47:59 +11:00 committed by Greg Kroah-Hartman
parent 1c6ce08297
commit 058643de84
1 changed files with 0 additions and 249 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

249
drivers/staging/lustre/lustre/include/lustre_lib.h
View File

@ -76,123 +76,6 @@ int do_set_info_async(struct obd_import *imp,
void target_send_reply(struct ptlrpc_request *req, int rc, int fail_id);
/*
* l_wait_event is a flexible sleeping function, permitting simple caller
* configuration of interrupt and timeout sensitivity along with actions to
* be performed in the event of either exception.
*
* The first form of usage looks like this:
*
* struct l_wait_info lwi = LWI_TIMEOUT_INTR(timeout, timeout_handler,
* intr_handler, callback_data);
* rc = l_wait_event(waitq, condition, &lwi);
*
* l_wait_event() makes the current process wait on 'waitq' until 'condition'
* is TRUE or a "killable" signal (SIGTERM, SIKGILL, SIGINT) is pending. It
* returns 0 to signify 'condition' is TRUE, but if a signal wakes it before
* 'condition' becomes true, it optionally calls the specified 'intr_handler'
* if not NULL, and returns -EINTR.
*
* If a non-zero timeout is specified, signals are ignored until the timeout
* has expired. At this time, if 'timeout_handler' is not NULL it is called.
* If it returns FALSE l_wait_event() continues to wait as described above with
* signals enabled. Otherwise it returns -ETIMEDOUT.
*
* LWI_INTR(intr_handler, callback_data) is shorthand for
* LWI_TIMEOUT_INTR(0, NULL, intr_handler, callback_data)
*
* The second form of usage looks like this:
*
* struct l_wait_info lwi = LWI_TIMEOUT(timeout, timeout_handler);
* rc = l_wait_event(waitq, condition, &lwi);
*
* This form is the same as the first except that it COMPLETELY IGNORES
* SIGNALS. The caller must therefore beware that if 'timeout' is zero, or if
* 'timeout_handler' is not NULL and returns FALSE, then the ONLY thing that
* can unblock the current process is 'condition' becoming TRUE.
*
* Another form of usage is:
* struct l_wait_info lwi = LWI_TIMEOUT_INTERVAL(timeout, interval,
* timeout_handler);
* rc = l_wait_event(waitq, condition, &lwi);
* This is the same as previous case, but condition is checked once every
* 'interval' jiffies (if non-zero).
*
* Subtle synchronization point: this macro does *not* necessary takes
* wait-queue spin-lock before returning, and, hence, following idiom is safe
* ONLY when caller provides some external locking:
*
* Thread1 Thread2
*
* l_wait_event(&obj->wq, ....); (1)
*
* wake_up(&obj->wq): (2)
* spin_lock(&q->lock); (2.1)
* __wake_up_common(q, ...); (2.2)
* spin_unlock(&q->lock, flags); (2.3)
*
* kfree(obj); (3)
*
* As l_wait_event() may "short-cut" execution and return without taking
* wait-queue spin-lock, some additional synchronization is necessary to
* guarantee that step (3) can begin only after (2.3) finishes.
*
* XXX nikita: some ptlrpc daemon threads have races of that sort.
*
*/
#define LWI_ON_SIGNAL_NOOP ((void (*)(void *))(-1))
struct l_wait_info {
long lwi_timeout;
long lwi_interval;
int lwi_allow_intr;
int (*lwi_on_timeout)(void *);
void (*lwi_on_signal)(void *);
void *lwi_cb_data;
};
/* NB: LWI_TIMEOUT ignores signals completely */
#define LWI_TIMEOUT(time, cb, data) \
((struct l_wait_info) { \
.lwi_timeout = time, \
.lwi_on_timeout = cb, \
.lwi_cb_data = data, \
.lwi_interval = 0, \
.lwi_allow_intr = 0 \
})
#define LWI_TIMEOUT_INTERVAL(time, interval, cb, data) \
((struct l_wait_info) { \
.lwi_timeout = time, \
.lwi_on_timeout = cb, \
.lwi_cb_data = data, \
.lwi_interval = interval, \
.lwi_allow_intr = 0 \
})
#define LWI_TIMEOUT_INTR(time, time_cb, sig_cb, data) \
((struct l_wait_info) { \
.lwi_timeout = time, \
.lwi_on_timeout = time_cb, \
.lwi_on_signal = sig_cb, \
.lwi_cb_data = data, \
.lwi_interval = 0, \
.lwi_allow_intr = 0 \
})
#define LWI_TIMEOUT_INTR_ALL(time, time_cb, sig_cb, data) \
((struct l_wait_info) { \
.lwi_timeout = time, \
.lwi_on_timeout = time_cb, \
.lwi_on_signal = sig_cb, \
.lwi_cb_data = data, \
.lwi_interval = 0, \
.lwi_allow_intr = 1 \
})
#define LWI_INTR(cb, data) LWI_TIMEOUT_INTR(0, NULL, cb, data)
#define LUSTRE_FATAL_SIGS (sigmask(SIGKILL) | sigmask(SIGINT) | \
sigmask(SIGTERM) | sigmask(SIGQUIT) | \
sigmask(SIGALRM))
@ -201,138 +84,6 @@ static inline int l_fatal_signal_pending(struct task_struct *p)
return signal_pending(p) && sigtestsetmask(&p->pending.signal, LUSTRE_FATAL_SIGS);
}
/**
* wait_queue_entry_t of Linux (version < 2.6.34) is a FIFO list for exclusively
* waiting threads, which is not always desirable because all threads will
* be waken up again and again, even user only needs a few of them to be
* active most time. This is not good for performance because cache can
* be polluted by different threads.
*
* LIFO list can resolve this problem because we always wakeup the most
* recent active thread by default.
*
* NB: please don't call non-exclusive & exclusive wait on the same
* waitq if add_wait_queue_exclusive_head is used.
*/
#define add_wait_queue_exclusive_head(waitq, link) \
{ \
unsigned long flags; \
\
spin_lock_irqsave(&((waitq)->lock), flags); \
__add_wait_queue_exclusive(waitq, link); \
spin_unlock_irqrestore(&((waitq)->lock), flags); \
}
/*
* wait for @condition to become true, but no longer than timeout, specified
* by @info.
*/
#define __l_wait_event(wq, condition, info, ret, l_add_wait) \
do { \
wait_queue_entry_t __wait; \
long __timeout = info->lwi_timeout; \
sigset_t __blocked; \
int __allow_intr = info->lwi_allow_intr; \
\
ret = 0; \
if (condition) \
break; \
\
init_waitqueue_entry(&__wait, current); \
l_add_wait(&wq, &__wait); \
\
/* Block all signals (just the non-fatal ones if no timeout). */ \
if (info->lwi_on_signal && (__timeout == 0 || __allow_intr)) \
__blocked = cfs_block_sigsinv(LUSTRE_FATAL_SIGS); \
else \
__blocked = cfs_block_sigsinv(0); \
\
for (;;) { \
if (condition) \
break; \
\
set_current_state(TASK_INTERRUPTIBLE); \
\
if (__timeout == 0) { \
schedule(); \
} else { \
long interval = info->lwi_interval ? \
min_t(long, \
info->lwi_interval, __timeout) : \
__timeout; \
long remaining = schedule_timeout(interval);\
__timeout = cfs_time_sub(__timeout, \
cfs_time_sub(interval, remaining));\
if (__timeout == 0) { \
if (!info->lwi_on_timeout || \
info->lwi_on_timeout(info->lwi_cb_data)) { \
ret = -ETIMEDOUT; \
break; \
} \
/* Take signals after the timeout expires. */ \
if (info->lwi_on_signal) \
(void)cfs_block_sigsinv(LUSTRE_FATAL_SIGS);\
} \
} \
\
set_current_state(TASK_RUNNING); \
\
if (condition) \
break; \
if (signal_pending(current)) { \
if (info->lwi_on_signal && \
(__timeout == 0 || __allow_intr)) { \
if (info->lwi_on_signal != LWI_ON_SIGNAL_NOOP) \
info->lwi_on_signal(info->lwi_cb_data);\
ret = -EINTR; \
break; \
} \
/* We have to do this here because some signals */ \
/* are not blockable - ie from strace(1). */ \
/* In these cases we want to schedule_timeout() */ \
/* again, because we don't want that to return */ \
/* -EINTR when the RPC actually succeeded. */ \
/* the recalc_sigpending() below will deliver the */ \
/* signal properly. */ \
cfs_clear_sigpending(); \
} \
} \
\
cfs_restore_sigs(__blocked); \
\
remove_wait_queue(&wq, &__wait); \
} while (0)
#define l_wait_event(wq, condition, info) \
({ \
int __ret; \
struct l_wait_info *__info = (info); \
\
__l_wait_event(wq, condition, __info, \
__ret, add_wait_queue); \
__ret; \
})
#define l_wait_event_exclusive(wq, condition, info) \
({ \
int __ret; \
struct l_wait_info *__info = (info); \
\
__l_wait_event(wq, condition, __info, \
__ret, add_wait_queue_exclusive); \
__ret; \
})
#define l_wait_event_exclusive_head(wq, condition, info) \
({ \
int __ret; \
struct l_wait_info *__info = (info); \
\
__l_wait_event(wq, condition, __info, \
__ret, add_wait_queue_exclusive_head); \
__ret; \
})
/** @} lib */