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Miller"</a></li></ul></li></ul></li></ul></li><li><a href="/lkml/2005/12/14/261">Jesper Juhl</a><ul><li><a href="/lkml/2005/12/14/266">Ben Greear</a></li><li><a href="/lkml/2005/12/14/270">James Courtier-Dutton</a><ul><li><a href="/lkml/2005/12/14/287">Sridhar Samudrala</a><ul><li><a href="/lkml/2005/12/14/292">James Courtier-Dutton</a></li></ul></li><li><a href="/lkml/2005/12/14/407">Mitchell Blank Jr</a><ul><li><a href="/lkml/2005/12/15/116">James Courtier-Dutton</a></li></ul></li></ul></li></ul></li></ul></li></ul></td><td width="32" rowspan="2" class="c" valign="top"><img src="/images/icornerl.gif" width="32" height="32" alt="/" /></td><td class="c" rowspan="2" valign="top" style="padding-top: 1em"><table><tr><td><table><tr><td class="lp">Subject</td><td class="rp" itemprop="name">Re: [RFC][PATCH 0/3] TCP/IP Critical socket communication mechanism</td></tr><tr><td class="lp">From</td><td class="rp" itemprop="author">Sridhar Samudrala <></td></tr><tr><td class="lp">Date</td><td class="rp" itemprop="datePublished">Wed, 14 Dec 2005 09:55:45 -0800</td></tr></table></td><td></td></tr></table><pre itemprop="articleBody">On Wed, 2005-12-14 at 10:22 +0100, Andi Kleen wrote:<br />> > I would appreciate any feedback or comments on this approach.<br />> <br />> Maybe I'm missing something but wouldn't you need an own critical<br />> pool (or at least reservation) for each socket to be safe against deadlocks?<br />> <br />> Otherwise if a critical sockets needs e.g. 2 pages to finish something<br />> and 2 critical sockets are active they can each steal the last pages<br />> from each other and deadlock.<br /><br />Here we are assuming that the pre-allocated critical page pool is big enough<br />to satisfy the requirements of all the critical sockets.<br /><br />In the current critical page pool implementation, there is also a limitation <br />that only order-0 allocations(single page) are supported. I think in the<br />networking send/receive patch, the only place where multi-page allocs are<br />requested is in the drivers if the MTU > PAGESIZE. But i guess the drivers<br />are getting updated to avoid > order-0 allocations.<br /><br />Also during the emergency, we free the memory allocated for non-critical <br />packets as quickly as possible so that it can be re-used for critical<br />allocations.<br /><br />Thanks<br />Sridhar<br /><br />-<br />To unsubscribe from this list: send the line "unsubscribe linux-kernel" in<br />the body of a message to majordomo@vger.kernel.org<br />More majordomo info at <a href="http://vger.kernel.org/majordomo-info.html">http://vger.kernel.org/majordomo-info.html</a><br />Please read the FAQ at <a href="http://www.tux.org/lkml/">http://www.tux.org/lkml/</a><br /><br /></pre></td><td width="32" rowspan="2" class="c" valign="top"><img src="/images/icornerr.gif" width="32" height="32" alt="\" /></td></tr><tr><td align="right" valign="bottom"> 聽 </td></tr><tr><td align="right" valign="bottom">聽</td><td class="c" valign="bottom" style="padding-bottom: 0px"><img src="/images/bcornerl.gif" width="32" height="32" alt="\" /></td><td class="c">聽</td><td class="c" valign="bottom" style="padding-bottom: 0px"><img src="/images/bcornerr.gif" width="32" height="32" alt="/" /></td></tr><tr><td align="right" valign="top" colspan="2"> 聽 </td><td class="lm">Last update: 2005-12-14 19:00 聽聽 [from the cache]<br />漏2003-2020 <a href="http://blog.jasper.es/"><span itemprop="editor">Jasper Spaans</span></a>|hosted at <a href="https://www.digitalocean.com/?refcode=9a8e99d24cf9">Digital Ocean</a> and my Meterkast|<a href="http://blog.jasper.es/categories.html#lkml-ref">Read the blog</a></td><td>聽</td></tr></table><script language="javascript" src="/js/styleswitcher.js" type="text/javascript"></script></body></html>