[Devel] Re: [RFC][v3][PATCH 7/7] Define clone_with_pids syscall

[Sukadev Bhattiprolu]

| Call clone_with_pids as follows:
| 
| 	pid_t pids[] = { 0, 77, 99 };
| 	struct target_pid_set pid_set;
| 
| 	pid_set.num_pids = sizeof(pids) / sizeof(int);
| 	pid_set.target_pids = &pids;
| 
| 	syscall(__NR_clone_with_pids, flags, stack, NULL, NULL, NULL, &pid_set);


Now that we need to do a copy_from_user() anyway, is it worth collapsing
one or more parameters into a structure ?

	struct clone_with_pid_args {
		u64 flags;
		void *stack;
		void *tls;
		struct target_pid_set *pid_set;
	};

	struct clone_tid_info {
		int *parent_tidptr;
		int *child_tidptr;
	}

	struct clone_with_pid_args cwp_args;
	struct clone_tid_info ctid_inf;

	...

	syscall(__NR_clone_with_pids, &cwp_args, &ctid_info);

One advantage would be that it would make room for 64 bit clone flags, so we
won't need a new flavor of clone_with_pids() when clone_flags is extended.

Sukadev
_______________________________________________
Containers mailing list
Containers at lists.linux-foundation.org
https://lists.linux-foundation.org/mailman/listinfo/containers