From e36b37583bebd229102f46c4ed7d2f6fad8697d4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Fri, 23 Jul 2021 13:24:09 +0200 Subject: Adding upstream version 0.6.0. Signed-off-by: Daniel Baumann --- doc/ck_ring_enqueue_spmc_size | 127 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 127 insertions(+) create mode 100644 doc/ck_ring_enqueue_spmc_size (limited to 'doc/ck_ring_enqueue_spmc_size') diff --git a/doc/ck_ring_enqueue_spmc_size b/doc/ck_ring_enqueue_spmc_size new file mode 100644 index 0000000..eb30cab --- /dev/null +++ b/doc/ck_ring_enqueue_spmc_size @@ -0,0 +1,127 @@ +.\" +.\" 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_ENQUEUE_SPMC_SIZE 3 +.Sh NAME +.Nm ck_ring_enqueue_spmc_size +.Nd enqueue pointer into bounded FIFO and return size of buffer +.Sh LIBRARY +Concurrency Kit (libck, \-lck) +.Sh SYNOPSIS +.In ck_ring.h +.Ft bool +.Fn ck_ring_enqueue_spmc_size "ck_ring_t *ring" "ck_ring_buffer_t *buffer" "void *entry" "unsigned int *length" +.Sh DESCRIPTION +The +.Fn ck_ring_enqueue_spmc 3 +function enqueues the pointer +.Fa entry +into the bounded buffer pointed to by +.Fa ring +in FIFO fashion. +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 entry . +This function is safe to call without locking for UINT_MAX +concurrent invocations of +.Fn ck_ring_dequeue_spmc 3 +or +.Fn ck_ring_trydequeue_spmc 3 . +This function provides wait-free progress +guarantees for one active invocation. +.Sh EXAMPLE +.Bd -literal -offset indent +#include + +/* 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 +enqueue(void) +{ + void *entry = some_object; + unsigned int length; + + /* Attempt to enqueue pointer to some_object into buffer. */ + if (ck_ring_enqueue_spmc_size(&ring, &buffer, &entry, &length) == false) { + /* + * The buffer was full and the enqueue operation + * has failed. + */ + return; + } + + /* + * If entry was the 101st or greater pointer in the buffer, + * do something. + */ + if (length > 100) { + do_something; + } + + return; +} +.Ed +.Sh RETURN VALUES +The function returns true if the value of +.Fa entry +was successfully enqueued into +.Fa ring . +The function will return false if the value of +.Fa entry +could not be enqueued which only occurs if +.Fa ring +was full. The number of entries in the buffer +with respect to the point in time that +.Fa entry +is enqueued is stored in the integer pointed to by +.Fa length . +.Sh SEE ALSO +.Xr ck_ring_init 3 , +.Xr ck_ring_dequeue_spmc 3 , +.Xr ck_ring_trydequeue_spmc 3 , +.Xr ck_ring_enqueue_spmc 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/ -- cgit v1.2.3