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Message-Id: <20060419190059.452500615@csdlinux-2.jf.intel.com>
Date: Wed, 19 Apr 2006 12:00:59 -0700
From: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
To: Anderw Morton <akpm@osdl.org>
Cc: LKML <linux-kernel@vger.kernel.org>, Keith Owens <kaos@americas.sgi.com>,
       Dean Nelson <dnc@americas.sgi.com>, Tony Luck <tony.luck@intel.com>,
       Ananth Mavinakayanahalli <ananth@in.ibm.com>,
       Prasanna Panchamukhi <prasanna@in.ibm.com>,
       Dave M <davem@davemloft.net>
Subject: [patch 0/6] Notify page fault call chain
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Hi Andrew,

Currently in the do_page_fault() code path, we call notify_die(DIE_PAGE_FAULT, ...)
to notify the page fault. The only interested components for this page fault
notifications are Kprobes and/or kdb. Since notify_die() is highly overloaded,
this page fault notification is currently being sent to other components
registered with register_die_notification() which uses the same die_chain to loop
for all the registered components.

In order to optimize the do_page_fault() code path, this critical page fault notification
is now moved to different call chain and the test results showed great improvements.

Patches for i386, x86_64, ia64, powerpc and sparc64 follows this mail.

Please apply.

Thanks,
Anil Keshavamurthy

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