Find references to struct members

[wagler]

Thank you for making Semcode. The query program is super useful when working with the Linux kernel.

Is there a way to find where members of a C struct are referenced in a Semcode-indexed codebase?
For example, in the Linux kernel, there's the struct rt_mutex_base type, which looks like this:

struct rt_mutex_base {
	raw_spinlock_t		wait_lock;
	struct rb_root_cached   waiters;
	struct task_struct	*owner;
}

I want to find all places in the kernel where the rt_mutex_base waiters member is referenced.

Using regular old grep, we can of course search for functions that use rt_mutex_base and then further filter the results for functions that contain .waiters or ->waiters. However, this can be tedious if there's lots of results, and can return false positives too.

For example, consider if there was some function like this:

struct foo { int waiters; };
void bar(struct rt_mutex_base* rtbase, struct foo* foo_ptr)
{
  ...
 foo_ptr->waiters = 0;
  ...
}

This would get caught in the grep search, because it contains a reference to struct rt_mutex_base and ->waiters. However, this isn't what we want, because it doesn't specifically reference struct rt_mutex_base's waiters member.

Is there some way Semcode can find all references to struct rt_mutex_base::waiters specifically?

[rikvanriel]

There isn't yet, but I have been thinking of adding something like that.

What remains to be seen is whether the cost of doing that would be prohibitive to most users.

We already have a million functions indexed in the Linux kernel tree. The number of data structures touched could be an order of magnitude larger than that.