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diff --git a/doc/ck_epoch_call b/doc/ck_epoch_call new file mode 100644 index 0000000..7390642 --- /dev/null +++ b/doc/ck_epoch_call @@ -0,0 +1,136 @@ +.\" +.\" 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 September 2, 2012 +.Dt CK_EPOCH_CALL 3 +.Sh NAME +.Nm ck_epoch_call +.Nd defer function execution until a grace period +.Sh LIBRARY +Concurrency Kit (libck, \-lck) +.Sh SYNOPSIS +.In ck_epoch.h +typedef struct ck_epoch_entry ck_epoch_entry_t; +.br +typedef void ck_epoch_cb_t(ck_epoch_entry_t *); +.Ft void +.Fn ck_epoch_call "ck_epoch_record_t *record" "ck_epoch_entry_t *entry" "ck_epoch_cb_t *function" +.Sh DESCRIPTION +The +.Fn ck_epoch_call 3 +function will defer the execution of the function pointed to by +.Fa function +until a grace-period has been detected in +.Fa epoch . +The function will be provided +the pointer specified by +.Fa entry . +The function will execute at some time in the future via calls to +.Fn ck_epoch_reclaim 3 , +.Fn ck_epoch_barrier 3 +or +.Fn ck_epoch_poll 3 . +.Sh EXAMPLE +.Bd -literal -offset indent + +#include <ck_epoch.h> +#include <ck_stack.h> +#include <stdlib.h> + +/* + * epoch was previously initialized with ck_epoch_init. + */ +ck_epoch_t *epoch; + +struct object { + int value; + ck_epoch_entry_t epoch_entry; +}; +static struct object *global; + +CK_EPOCH_CONTAINER(struct object, epoch_entry, object_container) + +void +destroy_object(ck_epoch_entry_t *e) +{ + struct object *o = object_container(e); + + free(o); + return; +} + +void +function(void) +{ + ck_epoch_record_t *record; + struct object *n; + + record = malloc(sizeof *record); + ck_epoch_register(&epoch, record); + + n = malloc(sizeof *n); + if (n == NULL) + return; + + n->value = 1; + + /* + * We are using an epoch section here because there are multiple + * writers. It is also an option to use other forms of blocking + * write-side synchronization such as mutexes. + */ + ck_epoch_begin(record); + n = ck_pr_fas_ptr(&global, n); + ck_epoch_end(record); + + /* Defer destruction of previous object. */ + ck_epoch_call(record, &n->epoch_entry, destroy_object); + + /* Poll epoch sub-system in non-blocking manner. */ + ck_epoch_poll(record); + return; +} +.Ed +.Sh RETURN VALUES +This function has no return value. +.Sh ERRORS +The object pointed to by +.Fa record +must have been previously registered via +.Fn ck_epoch_register 3 . +.Sh SEE ALSO +.Xr ck_epoch_init 3 , +.Xr ck_epoch_register 3 , +.Xr ck_epoch_unregister 3 , +.Xr ck_epoch_recycle 3 , +.Xr ck_epoch_poll 3 , +.Xr ck_epoch_synchronize 3 , +.Xr ck_epoch_reclaim 3 , +.Xr ck_epoch_barrier 3 , +.Xr ck_epoch_begin 3 , +.Xr ck_epoch_end 3 +.Pp +Additional information available at http://concurrencykit.org/ |