rcu-string.h

Go to the documentation of this file.

/*
 * Copyright (C) 2012 Red Hat.  All rights reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public
 * License v2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 021110-1307, USA.
 */

struct rcu_string {
    struct rcu_head rcu;
    char str[0];
};

static inline struct rcu_string *rcu_string_strdup(const char *src, gfp_t mask)
{
    size_t len = strlen(src) + 1;
    struct rcu_string *ret = kzalloc(sizeof(struct rcu_string) +
                     (len * sizeof(char)), mask);
    if (!ret)
        return ret;
    strncpy(ret->str, src, len);
    return ret;
}

static inline void rcu_string_free(struct rcu_string *str)
{
    if (str)
        kfree_rcu(str, rcu);
}

#define printk_in_rcu(fmt, ...) do {    \
    rcu_read_lock();        \
    printk(fmt, __VA_ARGS__);   \
    rcu_read_unlock();      \
} while (0)

#define printk_ratelimited_in_rcu(fmt, ...) do {    \
    rcu_read_lock();                \
    printk_ratelimited(fmt, __VA_ARGS__);       \
    rcu_read_unlock();              \
} while (0)

#define rcu_str_deref(rcu_str) ({               \
    struct rcu_string *__str = rcu_dereference(rcu_str);    \
    __str->str;                     \
})