[CRIU] [PATCH 3/4] deduplication: Compare predump files, old from "predump" directory

[Pavel Emelyanov]

> +		for (i = 0; i < nr; i++) {
> +			unsigned char buf[PAGE_SIZE];
> +			unsigned char buf2[PAGE_SIZE];
> +			
> +			ret = pr.read_page(&pr, va, buf);
> +			if (ret < 0) {
> +				pr_err("Can't read page");
> +				goto exit;
> +			}
> +
> +			ret = pr2.read_page(&pr2, va, buf2);
> +			if (ret < 0) {
> +				pr_err("Can't read page");
> +				goto exit;
> +			}
> +
> +			if (memcmp(buf, buf2, PAGE_SIZE) != 0) {
> +				pr_info("Pages Not Equal : %lu\n", va);
> +			} else {
> +
> +			}
> +			
> +			off++;
> +			va += PAGE_SIZE;

Don't compare page contents. Just punch holes from "parent" pages-%d.img files, that
have date in respective places in the working dir's pages-%.img ones.