[PATCH v4 1/7] PID namespace translation support

[Dmitry V. Levin]

On Mon, Jul 27, 2020 at 08:54:04PM +0200, Ákos Uzonyi wrote:
[...]
> +struct trie *ns_pid_to_proc_pid[PT_COUNT];
> +struct trie *proc_data_cache;
> +
> +bool ns_get_parent_enotty = false;

Could you make these variables static, please?

[...]
> +void
> +pidns_init(void)
> +{
> +	static bool inited = false;
> +	if (inited)
> +		return;
> +
> +	for (int i = 0; i < PT_COUNT; i++)
> +		ns_pid_to_proc_pid[i] = trie_create(6, 10, 10, 64, 0);
> +
> +	proc_data_cache = trie_create(6, 10, 10, 64, 0);
> +
> +	inited = true;
> +}

Do we need "inited" variable, or could we check "proc_data_cache" instead?

> +static bool
> +is_proc_ours(void)
> +{
> +	static int cached_val = -1;
> +
> +	if (cached_val < 0)
> +		cached_val = get_id_list(0, NULL, PT_TID) == 1;
> +
> +	return cached_val;
> +}
> +
> +static uint64_t
> +get_ns(struct tcb *tcp)
> +{
> +	if (!tcp->pid_ns_inited) {
> +		int proc_pid = 0;
> +
> +		if (is_proc_ours())
> +			proc_pid = tcp->pid;
> +		else
> +			translate_pid(NULL, tcp->pid, PT_TID, &proc_pid);
> +
> +		if (proc_pid)
> +			get_ns_hierarchy(proc_pid, &tcp->pid_ns, 1);
> +
> +		tcp->pid_ns_inited = true;
> +	}
> +
> +	return tcp->pid_ns;
> +}
> +
> +static uint64_t
> +get_our_ns(void)
> +{
> +	static uint64_t our_ns = 0;
> +	static bool our_ns_initialised = false;
> +
> +	if (!our_ns_initialised) {
> +		get_ns_hierarchy(0, &our_ns, 1);
> +		our_ns_initialised = true;
> +	}
> +
> +	return our_ns;
> +}

Could you add some short comments describing the purpose of these
functions, similar to other functions in this file, please?


-- 
ldv