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Diffstat (limited to 'doc/ck_ring_trydequeue_spmc')
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diff --git a/doc/ck_ring_trydequeue_spmc b/doc/ck_ring_trydequeue_spmc deleted file mode 100644 index 16f83eee4b9d..000000000000 --- a/doc/ck_ring_trydequeue_spmc +++ /dev/null @@ -1,126 +0,0 @@ -.\" -.\" Copyright 2012-2013 Samy Al Bahra. -.\" All rights reserved. -.\" -.\" Redistribution and use in source and binary forms, with or without -.\" modification, are permitted provided that the following conditions -.\" are met: -.\" 1. Redistributions of source code must retain the above copyright -.\" notice, this list of conditions and the following disclaimer. -.\" 2. Redistributions in binary form must reproduce the above copyright -.\" notice, this list of conditions and the following disclaimer in the -.\" documentation and/or other materials provided with the distribution. -.\" -.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND -.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE -.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE -.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE -.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL -.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS -.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) -.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT -.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY -.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF -.\" SUCH DAMAGE. -.\" -.\" -.Dd April 20, 2013 -.Dt CK_RING_TRYDEQUEUE_SPMC 3 -.Sh NAME -.Nm ck_ring_trydequeue_spmc -.Nd dequeue from bounded FIFO and allow for spurious failure -.Sh LIBRARY -Concurrency Kit (libck, \-lck) -.Sh SYNOPSIS -.In ck_ring.h -.Ft bool -.Fn ck_ring_trydequeue_spmc "ck_ring_t *ring" "ck_ring_buffer_t *buffer" "void *result" -.Sh DESCRIPTION -The -.Fn ck_ring_trydequeue_spmc 3 -function attempts to dequeue a pointer from the bounded buffer -pointed to by -.Fa ring -in FIFO fashion. The pointer is stored in the pointer -pointed to by -.Fa result . -The buffer pointed to by -.Fa buffer -must be unique to -.Fa ring -and point to an array of ck_ring_buffer_t of sufficient -length (according to the power-of-2 elements in the buffer). -The decoupling of the ring from the buffer serves -to address use-cases involving multiple address spaces -and DMA, among others. -If you are on non-POSIX platforms or wish for strict -compliance with C, then it is recommended to pass a -pointer of type void ** for -.Fa result . -This function is safe to call without locking for UINT_MAX -concurrent -.Fn ck_ring_dequeue_spmc 3 -or -.Fn ck_ring_trydequeue_spmc 3 -invocations and up to one concurrent -.Fn ck_ring_enqueue_spmc 3 -or -.Fn ck_ring_tryenqueue_spmc 3 -invocation. This operation will always complete -in a bounded number of steps. It is -possible for the function to return false even -if -.Fa ring -is non-empty. This -.Sh EXAMPLE -.Bd -literal -offset indent -#include <ck_ring.h> - -/* This ring was previously initialized with ck_ring_init. */ -ck_ring_t ring; - -/* The ring was initialized for 1023 elements. */ -ck_ring_buffer_t buffer[1024]; - -void -dequeue(void) -{ - void *result; - - /* Dequeue from ring until contention is actively observed. */ - while (ck_ring_trydequeue_spmc(&ring, &buffer, &result) == true) { - /* - * Results contains the oldest pointer in ring - * since the dequeue operation returned true. - */ - operation(result); - } - - /* An empty ring was encountered, leave. */ - return; -} -.Ed -.Sh RETURN VALUES -The function returns true if the dequeue operation -completely successfully in a bounded number of steps. -The result of the dequeue operation is stored in the -value pointed to by -.Fa result . -Otherwise, the function will return false if the buffer was empty -or if the operation could not be completed in a bounded -number of steps. If the function returns false, then the contents -of -.Fa result -are undefined. -.Sh SEE ALSO -.Xr ck_ring_init 3 , -.Xr ck_ring_dequeue_spmc 3 , -.Xr ck_ring_enqueue_spmc 3 , -.Xr ck_ring_enqueue_spmc_size 3 , -.Xr ck_ring_dequeue_spsc 3 , -.Xr ck_ring_enqueue_spsc 3 , -.Xr ck_ring_enqueue_spsc_size 3 , -.Xr ck_ring_capacity 3 , -.Xr ck_ring_size 3 -.Pp -Additional information available at http://concurrencykit.org/ |