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Sorry, I accidentally replied with html and broke the formating. > > I never tested in compat mode. I will do and look at all the points > mentioned above. > I will insist you to please do a complete review and kindly tell me if > any more such or any architecture specific issue exists. > > Regarding optimization on target retrieval from tree, can you provide > any suggestion how we can minimize complete traversal required for > each time. if we maintain state how we know the current cache or > stored efficient node belongs to which system calls from userspace if > we assume many concurrent processes calling it. My idea was to basically just have `struct rb_node **last = NULL;` in do_mq_recvmmsg() and pass it down to mq_peek_index(), so that we can start the walk from last instead of rb_last, just doing `node = rb_prev(last)` instead of full tree walk. You should set node back to last after that. Only thing we should be careful about is that info->msg_tree should be sufficiently locked to avoid removal of last from the tree. > > Thanks, > Mathura -- Best regards, Pavel Tikhomirov Senior Software Developer, Virtuozzo.