ck_epoch_call (3) - Linux Manuals

ck_epoch_call: defer function execution until a grace period

NAME

ck_epoch_call - defer function execution until a grace period

LIBRARY

Concurrency Kit (libck, -lck)

SYNOPSIS

In ck_epoch.h typedef struct ck_epoch_entry ck_epoch_entry_t;
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

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 .

EXAMPLE

#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;
}

RETURN VALUES

This function has no return value.

ERRORS

The object pointed to by Fa record must have been previously registered via Fn ck_epoch_register 3 .