Thanks for the patch, there are some minor style/cleanups that
could be done.
> #if defined(RTE_ARCH_X86)
Isn't this going to apply to 64 bit only?
> +/*
> + * Try to detect whether the system uses 5-level page table.
> + */
> +static bool
> +system_uses_PML5(void)
> +{
> + void *page_4k, *mask = (void *)0xf0000000000000;
Magic constants expressed like this seem wrong. Why not use
shift to make it obvious.
Also, you are assuming a particular layout of memory on
Linux which might be problematic. Plus if there is already
some memory in use there, it won't work.
> + page_4k = mmap(mask, 4096, PROT_READ | PROT_WRITE,
> + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
Since you are probing maybe MAP_FIXED is what you want.
> +
> + if (page_4k == (void *) -1)
> + return false;
Use MMAP_FAILED here.
> + munmap(page_4k, 4096);
> +
> + if ((unsigned long)page_4k & (unsigned long)mask)
> + return true;
> + return false;
Wouldn't this work the same for what you expect?
return page_4k == mask;
I.e you expect kernel to put page where you want.
