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Date: Fri, 21 Aug 2009 11:33:27 -0700
From: Arjan van de Ven <arjan@linux.intel.com>
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To: Linus Torvalds <torvalds@linux-foundation.org>
CC: mingo@redhat.com, "H. Peter Anvin" <hpa@zytor.com>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       a.p.zijlstra@chello.nl, catalin.marinas@arm.com,
       Jens Axboe <jens.axboe@oracle.com>, fweisbec@gmail.com,
       srostedt@redhat.com, tglx@linutronix.de, Ingo Molnar <mingo@elte.hu>
Subject: Re: [tip:tracing/urgent] tracing: Fix too large stack usage in do_one_initcall()
References: <new-submission> <tip-4a683bf94b8a10e2bb0da07aec3ac0a55e5de61f@git.kernel.org> <alpine.LFD.2.01.0908210845540.3158@localhost.localdomain>
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Linus Torvalds wrote:
> 
> I do wonder, though. Maybe we should never have that MAX_WORK limit, and 
> instead limit the parallelism by actively trying to yield when there's too 
> much work? That bootup sequence _does_ tend to have deep callchains (with 
> all the crazy device register crud), and maybe we should actively see the 
> async work code as not just a way to speed up boot, but also as a way to 
> avoid deep callchains.

makes sense; the MAX_WORK was more a sanity check to kill out of hand recursion
than anything else...