staging: lustre: remove l_wait_event() and related code
authorNeilBrown <neilb@suse.com>
Mon, 12 Feb 2018 23:47:59 +0000 (10:47 +1100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 16 Feb 2018 14:19:11 +0000 (15:19 +0100)
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>
drivers/staging/lustre/lustre/include/lustre_lib.h

index ccc1a32..1efd86f 100644 (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 */