Re: [RFC v12][PATCH 13/14] Checkpoint multiple processes

Nathan Lynch
2009-01-12T23:15:26Z

> +/* count number of tasks in tree (and optionally fill pid's in array) */
> +static int cr_tree_count_tasks(struct cr_ctx *ctx)
> +{
> + struct task_struct *root = ctx->root_task;
> + struct task_struct *task = root;
> + struct task_struct *parent = NULL;
> + struct task_struct **tasks_arr = ctx->tasks_arr;
> + int tasks_nr = ctx->tasks_nr;
> + int nr = 0;
> +
> + read_lock(&tasklist_lock);
> +
> + /* count tasks via DFS scan of the tree */
> + while (1) {
> + if (tasks_arr) {
> + /* unlikely, but ... */
> + if (nr == tasks_nr)
> + return -EBUSY; /* cleanup in cr_ctx_free() */

Returns without unlocking tasklist_lock?