On 14 January 2015 at 19:43, Rasmus Villemoes <li...@rasmusvillemoes.dk> wrote: > Just thinking out loud: Could one simply mark a VMA as being used for > stack during the clone call (is there room in vm_flags, or does > VM_GROWSDOWN already tell the whole story?), and then write the TID into > a new field in the VMA - I think one could make a union with vm_pgoff so > as not to enlarge the structure.
vm_flags does not have space IIRC (that was my first approach at implementing this) and VM_GROWSDOWN is not sufficient. If we can make a union with vm_pgoff like you say, we probably don't need a flag value; a non-zero value could indicate that it is a thread stack. One problem with caching the value on clone like this though is that the stack could change due to a setcontext, but AFAICT we don't care about that for the process stack either. Siddhesh -- http://siddhesh.in -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/