From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with ESMTP id 00D566B004D for ; Fri, 7 Aug 2009 03:50:44 -0400 (EDT) Date: Fri, 7 Aug 2009 09:50:30 +0200 From: Ingo Molnar Subject: Re: [PATCH 1/6] tracing, page-allocator: Add trace events for page allocation and page freeing Message-ID: <20090807075030.GB20292@elte.hu> References: <1249574827-18745-1-git-send-email-mel@csn.ul.ie> <1249574827-18745-2-git-send-email-mel@csn.ul.ie> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1249574827-18745-2-git-send-email-mel@csn.ul.ie> Sender: owner-linux-mm@kvack.org To: Mel Gorman Cc: Larry Woodman , Andrew Morton , riel@redhat.com, Peter Zijlstra , LKML , linux-mm@kvack.org List-ID: * Mel Gorman wrote: > +TRACE_EVENT(mm_pagevec_free, > + TP_fast_assign( > + __entry->page = page; > + __entry->order = order; > + __entry->cold = cold; > + ), > - while (--i >= 0) > + while (--i >= 0) { > + trace_mm_pagevec_free(pvec->pages[i], 0, pvec->cold); > free_hot_cold_page(pvec->pages[i], pvec->cold); > + } Pagevec freeing has order 0 implicit, so you can further optimize this by leaving out the 'order' field and using this format string: + TP_printk("page=%p pfn=%lu order=0 cold=%d", + __entry->page, + page_to_pfn(__entry->page), + __entry->cold) the trace record becomes smaller by 4 bytes and the tracepoint fastpath becomes shorter as well. Ingo -- 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/ . Don't email: email@kvack.org