[PATCH] tcp: revert to old definition of `before'

[PATCH] tcp: revert to old definition of `before'

[Gerrit Renker]

Hi Dave,

as per earlier email, can you please revert the definition of the
TCP `before' relation: there is code which implicitly depends on it.

Furthermore, this definition appears in textbooks such as Stevens
and therefore, even if the newer definition may have nicer properties,
it is safer to stick with the old one.

--------------------> Patch <-------------------------------------
[TCP]: Use old definition of before

This reverts the new (unambiguous) definition of the TCP `before'
relation. As pointed out in an example by Herbert Xu, there is 
existing code which implicitly requires the old definition in order
to work correctly.


Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
---

diff --git a/include/net/tcp.h b/include/net/tcp.h
index b7d8317..cd8fa0c 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -242,7 +242,7 @@ extern int tcp_memory_pressure;
 
 static inline int before(__u32 seq1, __u32 seq2)
 {
-        return (__s32)(seq2-seq1) > 0;
+        return (__s32)(seq1-seq2) < 0;
 }
 #define after(seq2, seq1) 	before(seq1, seq2)
 

Re: [PATCH] tcp: revert to old definition of `before'

[David Miller]

From: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Date: Thu, 4 Jan 2007 12:54:54 +0000

> Hi Dave,
> 
> as per earlier email, can you please revert the definition of the
> TCP `before' relation: there is code which implicitly depends on it.
> 
> Furthermore, this definition appears in textbooks such as Stevens
> and therefore, even if the newer definition may have nicer properties,
> it is safer to stick with the old one.

No problem, patch applied, thanks Gerrit.