Re: [PATCH 09/13] x86/tdx: Account shared memory

[Huang, Kai]

> +#ifdef CONFIG_DEBUG_FS
> +static int tdx_shared_memory_show(struct seq_file *m, void *p)
> +{
> +	unsigned long addr, end;
> +	unsigned long found = 0;
> +
> +	addr = PAGE_OFFSET;
> +	end  = PAGE_OFFSET + get_max_mapped();
> +
> +	while (addr < end) {
> +		unsigned long size;
> +		unsigned int level;
> +		pte_t *pte;
> +
> +		pte = lookup_address(addr, &level);
> +		size = page_level_size(level);
> +
> +		if (pte && pte_decrypted(*pte))
> +			found += size / PAGE_SIZE;
> +
> +		addr += size;

This could be a long loop, perhaps add cond_resched() here?

> +	}
> +
> +	seq_printf(m, "Number of unshared pages in kernel page tables:  %16lu\n",
> +		   found);
> +	seq_printf(m, "Number of pages accounted as unshared:           %16ld\n",
> +		   atomic_long_read(&nr_shared));
> +	return 0;
> +}
> +