From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: [kpreempt-tech] Re: Oops in kernel 2.4.19-pre10-ac2-preempt From: Robert Love In-Reply-To: <20020620172220.GT25360@holomorphy.com> References: <20020620171652.GS25360@holomorphy.com> <1024593564.922.151.camel@sinai> <20020620172220.GT25360@holomorphy.com> Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: 20 Jun 2002 10:58:21 -0700 Message-Id: <1024595902.1195.169.camel@sinai> Mime-Version: 1.0 Sender: owner-linux-mm@kvack.org Return-Path: To: William Lee Irwin III Cc: Mark_H_Johnson@Raytheon.com, kpreempt-tech@lists.sourceforge.net, linux-mm@kvack.org, Robert_Horton@Raytheon.com, James_P_Cassidy@Raytheon.com, Stanley_R_Allen@Raytheon.com List-ID: On Thu, 2002-06-20 at 10:22, William Lee Irwin III wrote: > That'd be great, the two places are pte_chain_lock() and pte_chain_unlock(). > They're basically a spin_lock_bit() and spin_unlock_bit(), so they need > the same kind of disable preempt before the spinloop and re-enable it after > dropping the lock treatment as spinlocks. Here is the patch... I will put out an updated -ac patch shortly with this and some other bits. Correct? Robert Love diff -urN linux-2.4.19-pre10-ac2/include/linux/mm.h linux/include/linux/mm.h --- linux-2.4.19-pre10-ac2/include/linux/mm.h Thu Jun 6 11:16:03 2002 +++ linux/include/linux/mm.h Thu Jun 20 10:57:01 2002 @@ -340,6 +340,7 @@ * busywait with less bus contention for a good time to * attempt to acquire the lock bit. */ + preempt_disable(); while (test_and_set_bit(PG_chainlock, &page->flags)) { while (test_bit(PG_chainlock, &page->flags)) cpu_relax(); @@ -349,6 +350,7 @@ static inline void pte_chain_unlock(struct page *page) { clear_bit(PG_chainlock, &page->flags); + preempt_enable(); } /* -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/