diff options
| -rw-r--r-- | include/os/freebsd/spl/sys/condvar.h | 36 | ||||
| -rw-r--r-- | include/os/linux/spl/sys/condvar.h | 48 | ||||
| -rw-r--r-- | include/sys/zfs_context.h | 4 | ||||
| -rw-r--r-- | lib/libzpool/kernel.c | 4 | ||||
| -rw-r--r-- | module/os/linux/spl/spl-condvar.c | 33 | ||||
| -rw-r--r-- | module/zfs/zil.c | 4 |
6 files changed, 93 insertions, 36 deletions
diff --git a/include/os/freebsd/spl/sys/condvar.h b/include/os/freebsd/spl/sys/condvar.h index ff5f308e2..4375bd6a3 100644 --- a/include/os/freebsd/spl/sys/condvar.h +++ b/include/os/freebsd/spl/sys/condvar.h @@ -37,6 +37,31 @@ #include <sys/time.h> #include <sys/kmem.h> +/* + * cv_timedwait() is similar to cv_wait() except that it additionally expects + * a timeout value specified in ticks. When woken by cv_signal() or + * cv_broadcast() it returns 1, otherwise when the timeout is reached -1 is + * returned. + * + * cv_timedwait_sig() behaves the same as cv_timedwait() but blocks + * interruptibly and can be woken by a signal (EINTR, ERESTART). When + * this occurs 0 is returned. + * + * cv_timedwait_io() and cv_timedwait_sig_io() are variants of cv_timedwait() + * and cv_timedwait_sig() which should be used when waiting for outstanding + * IO to complete. They are responsible for updating the iowait accounting + * when this is supported by the platform. + * + * cv_timedwait_hires() and cv_timedwait_sig_hires() are high resolution + * versions of cv_timedwait() and cv_timedwait_sig(). They expect the timeout + * to be specified as a hrtime_t allowing for timeouts of less than a tick. + * + * N.B. The return values differ slightly from the illumos implementation + * which returns the time remaining, instead of 1, when woken. They both + * return -1 on timeout. Consumers which need to know the time remaining + * are responsible for tracking it themselves. + */ + static __inline sbintime_t zfs_nstosbt(int64_t _ns) { @@ -120,7 +145,7 @@ cv_timedwait_sig(kcondvar_t *cvp, kmutex_t *mp, clock_t timo) #define cv_timedwait_io cv_timedwait #define cv_timedwait_sig_io cv_timedwait_sig -static inline clock_t +static inline int cv_timedwait_hires(kcondvar_t *cvp, kmutex_t *mp, hrtime_t tim, hrtime_t res, int flag) { @@ -135,7 +160,6 @@ cv_timedwait_hires(kcondvar_t *cvp, kmutex_t *mp, hrtime_t tim, hrtime_t res, if (hrtime >= tim) return (-1); - rc = cv_timedwait_sbt(cvp, mp, zfs_nstosbt(tim), zfs_nstosbt(res), C_ABSOLUTE); @@ -143,11 +167,10 @@ cv_timedwait_hires(kcondvar_t *cvp, kmutex_t *mp, hrtime_t tim, hrtime_t res, return (-1); KASSERT(rc == 0, ("unexpected rc value %d", rc)); - hrtime = tim - gethrtime(); - return ((hrtime > 0) ? hrtime : -1); + return (1); } -static inline clock_t +static inline int cv_timedwait_sig_hires(kcondvar_t *cvp, kmutex_t *mp, hrtime_t tim, hrtime_t res, int flag) { @@ -175,8 +198,7 @@ cv_timedwait_sig_hires(kcondvar_t *cvp, kmutex_t *mp, hrtime_t tim, return (0); default: KASSERT(rc == 0, ("unexpected rc value %d", rc)); - hrtime = tim - gethrtime(); - return ((hrtime > 0) ? hrtime : -1); + return (1); } } diff --git a/include/os/linux/spl/sys/condvar.h b/include/os/linux/spl/sys/condvar.h index f1438c4e2..22408824f 100644 --- a/include/os/linux/spl/sys/condvar.h +++ b/include/os/linux/spl/sys/condvar.h @@ -33,6 +33,32 @@ #include <sys/time.h> /* + * cv_timedwait() is similar to cv_wait() except that it additionally expects + * a timeout value specified in ticks. When woken by cv_signal() or + * cv_broadcast() it returns 1, otherwise when the timeout is reached -1 is + * returned. + * + * cv_timedwait_sig() behaves the same as cv_timedwait() but blocks + * interruptibly and can be woken by a signal (EINTR, ERESTART). When + * this occurs 0 is returned. + * + * cv_timedwait_io() and cv_timedwait_sig_io() are variants of cv_timedwait() + * and cv_timedwait_sig() which should be used when waiting for outstanding + * IO to complete. They are responsible for updating the iowait accounting + * when this is supported by the platform. + * + * cv_timedwait_hires() and cv_timedwait_sig_hires() are high resolution + * versions of cv_timedwait() and cv_timedwait_sig(). They expect the timeout + * to be specified as a hrtime_t allowing for timeouts of less than a tick. + * + * N.B. The return values differ slightly from the illumos implementation + * which returns the time remaining, instead of 1, when woken. They both + * return -1 on timeout. Consumers which need to know the time remaining + * are responsible for tracking it themselves. + */ + + +/* * The kcondvar_t struct is protected by mutex taken externally before * calling any of the wait/signal funs, and passed into the wait funs. */ @@ -56,12 +82,12 @@ extern void __cv_wait(kcondvar_t *, kmutex_t *); extern void __cv_wait_io(kcondvar_t *, kmutex_t *); extern int __cv_wait_io_sig(kcondvar_t *, kmutex_t *); extern int __cv_wait_sig(kcondvar_t *, kmutex_t *); -extern clock_t __cv_timedwait(kcondvar_t *, kmutex_t *, clock_t); -extern clock_t __cv_timedwait_io(kcondvar_t *, kmutex_t *, clock_t); -extern clock_t __cv_timedwait_sig(kcondvar_t *, kmutex_t *, clock_t); -extern clock_t cv_timedwait_hires(kcondvar_t *, kmutex_t *, hrtime_t, +extern int __cv_timedwait(kcondvar_t *, kmutex_t *, clock_t); +extern int __cv_timedwait_io(kcondvar_t *, kmutex_t *, clock_t); +extern int __cv_timedwait_sig(kcondvar_t *, kmutex_t *, clock_t); +extern int cv_timedwait_hires(kcondvar_t *, kmutex_t *, hrtime_t, hrtime_t res, int flag); -extern clock_t cv_timedwait_sig_hires(kcondvar_t *, kmutex_t *, hrtime_t, +extern int cv_timedwait_sig_hires(kcondvar_t *, kmutex_t *, hrtime_t, hrtime_t res, int flag); extern void __cv_signal(kcondvar_t *); extern void __cv_broadcast(kcondvar_t *c); @@ -72,12 +98,16 @@ extern void __cv_broadcast(kcondvar_t *c); #define cv_wait_io(cvp, mp) __cv_wait_io(cvp, mp) #define cv_wait_io_sig(cvp, mp) __cv_wait_io_sig(cvp, mp) #define cv_wait_sig(cvp, mp) __cv_wait_sig(cvp, mp) -#define cv_wait_interruptible(cvp, mp) cv_wait_sig(cvp, mp) +#define cv_signal(cvp) __cv_signal(cvp) +#define cv_broadcast(cvp) __cv_broadcast(cvp) + +/* + * NB: There is no way to reliably distinguish between having been signalled + * and having timed out on Linux. If the client code needs to reliably + * distinguish between the two it should use the hires variant. + */ #define cv_timedwait(cvp, mp, t) __cv_timedwait(cvp, mp, t) #define cv_timedwait_io(cvp, mp, t) __cv_timedwait_io(cvp, mp, t) #define cv_timedwait_sig(cvp, mp, t) __cv_timedwait_sig(cvp, mp, t) -#define cv_timedwait_interruptible(cvp, mp, t) cv_timedwait_sig(cvp, mp, t) -#define cv_signal(cvp) __cv_signal(cvp) -#define cv_broadcast(cvp) __cv_broadcast(cvp) #endif /* _SPL_CONDVAR_H */ diff --git a/include/sys/zfs_context.h b/include/sys/zfs_context.h index 72fcd74ca..7d5567db4 100644 --- a/include/sys/zfs_context.h +++ b/include/sys/zfs_context.h @@ -315,8 +315,8 @@ extern void cv_init(kcondvar_t *cv, char *name, int type, void *arg); extern void cv_destroy(kcondvar_t *cv); extern void cv_wait(kcondvar_t *cv, kmutex_t *mp); extern int cv_wait_sig(kcondvar_t *cv, kmutex_t *mp); -extern clock_t cv_timedwait(kcondvar_t *cv, kmutex_t *mp, clock_t abstime); -extern clock_t cv_timedwait_hires(kcondvar_t *cvp, kmutex_t *mp, hrtime_t tim, +extern int cv_timedwait(kcondvar_t *cv, kmutex_t *mp, clock_t abstime); +extern int cv_timedwait_hires(kcondvar_t *cvp, kmutex_t *mp, hrtime_t tim, hrtime_t res, int flag); extern void cv_signal(kcondvar_t *cv); extern void cv_broadcast(kcondvar_t *cv); diff --git a/lib/libzpool/kernel.c b/lib/libzpool/kernel.c index d19ecc18f..f19ebac12 100644 --- a/lib/libzpool/kernel.c +++ b/lib/libzpool/kernel.c @@ -344,7 +344,7 @@ cv_wait_sig(kcondvar_t *cv, kmutex_t *mp) return (1); } -clock_t +int cv_timedwait(kcondvar_t *cv, kmutex_t *mp, clock_t abstime) { int error; @@ -378,7 +378,7 @@ cv_timedwait(kcondvar_t *cv, kmutex_t *mp, clock_t abstime) } /*ARGSUSED*/ -clock_t +int cv_timedwait_hires(kcondvar_t *cv, kmutex_t *mp, hrtime_t tim, hrtime_t res, int flag) { diff --git a/module/os/linux/spl/spl-condvar.c b/module/os/linux/spl/spl-condvar.c index 3cc33da62..9d045e3e8 100644 --- a/module/os/linux/spl/spl-condvar.c +++ b/module/os/linux/spl/spl-condvar.c @@ -301,10 +301,10 @@ __cv_timedwait_common(kcondvar_t *cvp, kmutex_t *mp, clock_t expire_time, * with a thread holding the mutex and call cv_destroy. */ mutex_enter(mp); - return (time_left > 0 ? time_left : -1); + return (time_left > 0 ? 1 : -1); } -clock_t +int __cv_timedwait(kcondvar_t *cvp, kmutex_t *mp, clock_t exp_time) { return (__cv_timedwait_common(cvp, mp, exp_time, @@ -312,7 +312,7 @@ __cv_timedwait(kcondvar_t *cvp, kmutex_t *mp, clock_t exp_time) } EXPORT_SYMBOL(__cv_timedwait); -clock_t +int __cv_timedwait_io(kcondvar_t *cvp, kmutex_t *mp, clock_t exp_time) { return (__cv_timedwait_common(cvp, mp, exp_time, @@ -320,11 +320,13 @@ __cv_timedwait_io(kcondvar_t *cvp, kmutex_t *mp, clock_t exp_time) } EXPORT_SYMBOL(__cv_timedwait_io); -clock_t +int __cv_timedwait_sig(kcondvar_t *cvp, kmutex_t *mp, clock_t exp_time) { - return (__cv_timedwait_common(cvp, mp, exp_time, - TASK_INTERRUPTIBLE, 0)); + int rc; + + rc = __cv_timedwait_common(cvp, mp, exp_time, TASK_INTERRUPTIBLE, 0); + return (signal_pending(current) ? 0 : rc); } EXPORT_SYMBOL(__cv_timedwait_sig); @@ -341,6 +343,7 @@ __cv_timedwait_hires(kcondvar_t *cvp, kmutex_t *mp, hrtime_t expire_time, hrtime_t time_left; ktime_t ktime_left; u64 slack = 0; + int rc; ASSERT(cvp); ASSERT(mp); @@ -371,7 +374,7 @@ __cv_timedwait_hires(kcondvar_t *cvp, kmutex_t *mp, hrtime_t expire_time, ktime_left = ktime_set(0, time_left); slack = MIN(MAX(res, spl_schedule_hrtimeout_slack_us * NSEC_PER_USEC), MAX_HRTIMEOUT_SLACK_US * NSEC_PER_USEC); - schedule_hrtimeout_range(&ktime_left, slack, HRTIMER_MODE_REL); + rc = schedule_hrtimeout_range(&ktime_left, slack, HRTIMER_MODE_REL); /* No more waiters a different mutex could be used */ if (atomic_dec_and_test(&cvp->cv_waiters)) { @@ -387,14 +390,13 @@ __cv_timedwait_hires(kcondvar_t *cvp, kmutex_t *mp, hrtime_t expire_time, atomic_dec(&cvp->cv_refs); mutex_enter(mp); - time_left = expire_time - gethrtime(); - return (time_left > 0 ? NSEC_TO_TICK(time_left) : -1); + return (rc == -EINTR ? 1 : -1); } /* * Compatibility wrapper for the cv_timedwait_hires() Illumos interface. */ -static clock_t +static int cv_timedwait_hires_common(kcondvar_t *cvp, kmutex_t *mp, hrtime_t tim, hrtime_t res, int flag, int state) { @@ -404,7 +406,7 @@ cv_timedwait_hires_common(kcondvar_t *cvp, kmutex_t *mp, hrtime_t tim, return (__cv_timedwait_hires(cvp, mp, tim, res, state)); } -clock_t +int cv_timedwait_hires(kcondvar_t *cvp, kmutex_t *mp, hrtime_t tim, hrtime_t res, int flag) { @@ -413,12 +415,15 @@ cv_timedwait_hires(kcondvar_t *cvp, kmutex_t *mp, hrtime_t tim, hrtime_t res, } EXPORT_SYMBOL(cv_timedwait_hires); -clock_t +int cv_timedwait_sig_hires(kcondvar_t *cvp, kmutex_t *mp, hrtime_t tim, hrtime_t res, int flag) { - return (cv_timedwait_hires_common(cvp, mp, tim, res, flag, - TASK_INTERRUPTIBLE)); + int rc; + + rc = cv_timedwait_hires_common(cvp, mp, tim, res, flag, + TASK_INTERRUPTIBLE); + return (signal_pending(current) ? 0 : rc); } EXPORT_SYMBOL(cv_timedwait_sig_hires); diff --git a/module/zfs/zil.c b/module/zfs/zil.c index 34495af55..50b3b1434 100644 --- a/module/zfs/zil.c +++ b/module/zfs/zil.c @@ -2687,11 +2687,11 @@ zil_commit_waiter(zilog_t *zilog, zil_commit_waiter_t *zcw) * timeout is reached; responsibility (2) from * the comment above this function. */ - clock_t timeleft = cv_timedwait_hires(&zcw->zcw_cv, + int rc = cv_timedwait_hires(&zcw->zcw_cv, &zcw->zcw_lock, wakeup, USEC2NSEC(1), CALLOUT_FLAG_ABSOLUTE); - if (timeleft != -1 || zcw->zcw_done) + if (rc != -1 || zcw->zcw_done) continue; timedout = B_TRUE; |