[asterisk-bugs] [DAHDI-linux 0013483]: [patch] Add TDMoE Multi-Frame support

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=13483 
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Reported By:                JBenden
Assigned To:                kpfleming
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Project:                    DAHDI-linux
Issue ID:                   13483
Category:                   dahdi_dynamic
Reproducibility:            N/A
Severity:                   feature
Priority:                   normal
Status:                     ready for testing
JIRA:                        
Reviewboard Link:            
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Date Submitted:             2008-09-15 04:17 CDT
Last Modified:              2010-01-16 19:27 CST
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Summary:                    [patch] Add TDMoE Multi-Frame support
Description: 
A patch against SVN rev 4904, to add TDMoE Multi-Frame support as described
in the article at the following URL:

http://www.thrallingpenguin.com/articles/tdmoe-mf.htm

TDMoE-MF is known to be implemented in hardware solutions from Redfone
Communications.

This patch additionally implements RCU within dahdi_dynamic to decrease
lock contention, latency, and context switching. Because of the use of RCU
locking, all prior known issues with loading and unloading of the modules
are resolved, providing the spans are shutdown with "dahdi_cfg -s".

It also contains an attempt, which works, at fixing a kernel change with
skb_linearize(). The use of kernel version number does not work with SuSE
SLES 10, as it appears they have backported the 2.6.18 change in to their
2.6.16 version.
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Relationships       ID      Summary
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has duplicate       0012241 [patch] New Ztdynamic driver for Redfon...
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 (0116781) JBenden (reporter) - 2010-01-16 19:27
 https://issues.asterisk.org/view.php?id=13483#c116781 
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The gains are indeed worth the use. It solves high lock usage and context
switching. The use of RCU also solved a long standing bug of the dynamic
subsystem crashing upon an unload. In general, the dynamic modules are some
of the least maintained Zaptel/Dahdi code; for which I'm trying to help do
this. :)

Seeing how RCU API is a part of the Linux kernel, I personally see no
reason to be concerned with portability. It is well discussed within books,
the kernel docs, research papers, and the Linux source itself. It is to my
knowledge the available Dahdi drivers, from Digium, support only Linux; so
I see no reason for concern with the usage of RCU API. 

Issue History 
Date Modified    Username       Field                    Change               
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2010-01-16 19:27 JBenden        Note Added: 0116781                          
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