Re: [PATCH] loop unrolling in net/sched/sch_generic.c
From: Thomas Graf <tgraf@suug.ch>
Date: 2005-07-05 12:03:27
From: Thomas Graf <tgraf@suug.ch>
Date: 2005-07-05 12:03:27
* Thomas Graf [ref] 2005-07-05 13:51
* Eric Dumazet [ref] 2005-07-05 09:38quoted
[NET] : unroll a small loop in pfifo_fast_dequeue(). Compiler generates better code. (Using skb_queue_empty() to test the queue is faster than trying to __skb_dequeue()) oprofile says this function uses now 0.29% instead of 1.22 %, on a x86_64 target.I think this patch is pretty much pointless. __skb_dequeue() and !skb_queue_empty() should produce almost the same code and as soon as you disable profiling and debugging you'll see that the compiler unrolls the loop itself if possible.
... given one enables it of course.