On Thu, Oct 22, 2015 at 05:15:09PM +0200, Peter Zijlstra wrote: > Indefinitely is such a long time, we should try and finish > computation before the computer dies etc. :-) Indefinitely as read_seqcount_retry, eventually it makes progress. Even returning 0 from the page fault can trigger it again indefinitely, so VM_FAULT_RETRY isn't fundamentally different from returning 0 and retrying the page fault again later. So it's not clear why VM_FAULT_RETRY can only try once more. FAULT_FLAG_TRIED as a message to the VM so it starts to do heavy locking and block more aggressively is actually useful as such, but it shouldn't be a replacement of FAULT_FLAG_ALLOW_RETRY. What I meant with removing FAULT_FLAG_TRIED is really about converting it to an hint, but not controlling if the page fault can keep retrying in-kernel. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>