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<p class=MsoNormal><span style='color:#1F497D'>Stan,<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>We found a problem at this patch
and it should not be applied because of the lock is always taken at upper
layer.<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>I apologize for the bad patch<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
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<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'>
<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Smith, Stan
[mailto:stan.smith@intel.com] <br>
<b>Sent:</b> Friday, November 26, 2010 8:06 PM<br>
<b>To:</b> Alex Naslednikov; ofw@lists.openfabrics.org<br>
<b>Subject:</b> RE: [ofw] [Patch][IPoIB_NDIS6_CM] Take a lock when calling __endpt_mgr_insert
()<o:p></o:p></span></p>
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<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:blue'>Hello,</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:blue'> Although your patch is correct, it brings to light a
minor issue.</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'> <o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:blue'>In two places [__recv_get_endpts() & __recv_arp()]
calls to 'status = __endpt_mgr_insert()', the port lock is not released
immediately after the insert call.</span><span style='font-size:12.0pt;
font-family:"Times New Roman","serif"'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:blue'>Instead the lock is held until after the 'status' is checked, thus
resulting in a extra call to port unlock if the status != 0.</span><span
style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:blue'>The code could be cleaned up by releasing the port lock immediately
after the __endpt_mgr_insert() call as shown in your patch.</span><span
style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'> <o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:blue'>stan.</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'> <o:p></o:p></span></p>
<div class=MsoNormal align=center style='text-align:center'><span
style='font-size:12.0pt;font-family:"Times New Roman","serif"'>
<hr size=2 width="100%" align=center>
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<p class=MsoNormal style='margin-bottom:12.0pt'><b><span style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'> ofw-bounces@lists.openfabrics.org
[mailto:ofw-bounces@lists.openfabrics.org] <b>On Behalf Of </b>Alex Naslednikov<br>
<b>Sent:</b> Thursday, November 25, 2010 1:54 AM<br>
<b>To:</b> ofw@lists.openfabrics.org<br>
<b>Subject:</b> [ofw] [Patch][IPoIB_NDIS6_CM] Take a lock when calling
__endpt_mgr_insert ()</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p>
<p class=MsoNormal>__endpt_mgr_insert () <span style='color:#1F497D'>works with
CL objects like queues that are not thread-safe.<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>In order to protect on these
objects, one need to take a lock<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>Signed-off by: Alexander
Naslednikov (xalex at mellanox.co.il)<o:p></o:p></span></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Index: ulp/ipoib_NDIS6_CM/kernel/ipoib_port.cpp<o:p></o:p></p>
<p class=MsoNormal>===================================================================<o:p></o:p></p>
<p class=MsoNormal>---
ulp/ipoib_NDIS6_CM/kernel/ipoib_port.cpp
(revision 2999)<o:p></o:p></p>
<p class=MsoNormal>+++ ulp/ipoib_NDIS6_CM/kernel/ipoib_port.cpp
(working copy)<o:p></o:p></p>
<p class=MsoNormal>@@ -7242,9 +7242,11 @@<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>
/* __endpt_mgr_insert expects *one* reference to be held. */<o:p></o:p></p>
<p class=MsoNormal>
cl_atomic_inc( &p_port->endpt_rdr );<o:p></o:p></p>
<p class=MsoNormal>+
cl_obj_lock( &p_port->obj );<o:p></o:p></p>
<p class=MsoNormal>
status = __endpt_mgr_insert( p_port,<o:p></o:p></p>
<p class=MsoNormal>
p_port->p_adapter->params.conf_mac,<o:p></o:p></p>
<p class=MsoNormal>
p_endpt );<o:p></o:p></p>
<p class=MsoNormal>+
cl_obj_unlock( &p_port->obj );<o:p></o:p></p>
<p class=MsoNormal>
cl_atomic_dec( &p_port->endpt_rdr );<o:p></o:p></p>
<p class=MsoNormal>
if( status != IB_SUCCESS )<o:p></o:p></p>
<p class=MsoNormal>
{<o:p></o:p></p>
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