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Date: Fri, 29 Apr 2016 01:19:09 +0000
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From: "sepherosa_gmail.com (Sepherosa Ziehau)" <phabric-noreply@FreeBSD.org>
Reply-to: D6137+325+f015369c65104c2f@reviews.freebsd.org
Subject: [Differential] D6137: tcp/lro: Refactor the free/active list
 operation.
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sepherosa_gmail.com added a comment.


  In https://reviews.freebsd.org/D6137#130603, @gallatin wrote:
  
  > The tcp_lro_entry_get() abstraction adds an extra compare to the critical path (the compare against NULL in the function itself, in addition to the same compare in the main routine).  At least it does at the C level.   Have you verified that the compiler is smart enough to continue to use a single compare?
  >
  > If this adds an extra compare to the actual executed code, then I object.
  
  
  OK, I see your concern.  I think instead of depending on the compiler, we probably just leave the original code for the free list unchanged :).

REVISION DETAIL
  https://reviews.freebsd.org/D6137

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To: sepherosa_gmail.com, network, transport, adrian, delphij, glebius, hselasky, np, decui_microsoft.com, honzhan_microsoft.com, howard0su_gmail.com, gallatin, rrs
Cc: freebsd-net-list