[sheepdog] [PATCH 1/2] sheep: journaling epoch file write

[Hitoshi Mitake]

At Wed,  3 Apr 2013 15:06:16 +0800,
Liu Yuan wrote:
> 
> From: Liu Yuan <tailai.ly at taobao.com>
> 
> Also bundle two writes into one.
> 
> Signed-off-by: Liu Yuan <tailai.ly at taobao.com>
> ---
>  sheep/store.c |   31 +++++++++++++++++++------------
>  1 file changed, 19 insertions(+), 12 deletions(-)
> 
> diff --git a/sheep/store.c b/sheep/store.c
> index 5b1e457..f112751 100644
> --- a/sheep/store.c
> +++ b/sheep/store.c
> @@ -39,28 +39,35 @@ LIST_HEAD(store_drivers);
>  
>  int update_epoch_log(uint32_t epoch, struct sd_node *nodes, size_t nr_nodes)
>  {
> -	int fd, ret, len;
> +	int fd, ret, len, nodes_len, flags = O_RDWR | O_CREAT | O_DSYNC;
>  	time_t t;
> -	char path[PATH_MAX];
> +	char path[PATH_MAX], *buf;
>  
>  	sd_dprintf("update epoch: %d, %zd", epoch, nr_nodes);
>  
> +	/* Piggyback the epoch creation time for 'collie cluster info' */
> +	time(&t);
> +	nodes_len = nr_nodes * sizeof(struct sd_node);
> +	len = nodes_len + sizeof(time_t);
> +	buf = xmalloc(len);
> +	memcpy(buf, nodes, nodes_len);
> +	memcpy(buf + nodes_len, &t, sizeof(time_t));
> +
> +	if (uatomic_is_true(&sys->use_journal) &&
> +	    journal_write_epoch(buf, len, epoch) != SD_RES_SUCCESS) {
> +		sd_eprintf("turn off journaling");
> +		uatomic_set_false(&sys->use_journal);
> +		sync();
> +	}
> +
>  	snprintf(path, sizeof(path), "%s%08u", epoch_path, epoch);
> -	fd = open(path, O_RDWR | O_CREAT | O_DSYNC, def_fmode);
> +	fd = open(path, flags, def_fmode);
>  	if (fd < 0) {
>  		ret = fd;
>  		goto err_open;
>  	}
>  
> -	len = nr_nodes * sizeof(struct sd_node);
> -	ret = xwrite(fd, (char *)nodes, len);
> -	if (ret != len)
> -		goto err;
> -
> -	/* Piggyback the epoch creation time for 'collie cluster info' */
> -	time(&t);
> -	len = sizeof(t);
> -	ret = xwrite(fd, (char *)&t, len);
> +	ret = xwrite(fd, buf, len);
>  	if (ret != len)
>  		goto err;
>  

update_epoch_log() seems to lack free(buf);

Thanks,
Hitoshi