From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx138.postini.com [74.125.245.138]) by kanga.kvack.org (Postfix) with SMTP id 3E4F66B0005 for ; Thu, 28 Feb 2013 16:33:48 -0500 (EST) Message-ID: <1362087226.1231.21.camel@gandalf.local.home> Subject: Re: [PATCH RESEND] mm: trace filemap add and del From: Steven Rostedt Date: Thu, 28 Feb 2013 16:33:46 -0500 In-Reply-To: <1362084420-3840-1-git-send-email-robert.jarzmik@free.fr> References: <1362084420-3840-1-git-send-email-robert.jarzmik@free.fr> Content-Type: text/plain; charset="ISO-8859-15" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Robert Jarzmik Cc: linux-mm@kvack.org, Dave Chinner , Hugh Dickins , Frederic Weisbecker , Ingo Molnar , Andrew Morton On Thu, 2013-02-28 at 21:47 +0100, Robert Jarzmik wrote: > Use the events API to trace filemap loading and unloading of file pieces > into the page cache. > > This patch aims at tracing the eviction reload cycle of executable and > shared libraries pages in a memory constrained environment. > > The typical usage is to spot a specific device and inode (for example > /lib/libc.so) to see the eviction cycles, and find out if frequently used > code is rather spread across many pages (bad) or coallesced (good). > > Signed-off-by: Robert Jarzmik > Cc: Dave Chinner > Cc: Hugh Dickins > Cc: Steven Rostedt > Cc: Frederic Weisbecker > Cc: Ingo Molnar > Signed-off-by: Andrew Morton > --- > include/trace/events/filemap.h | 79 ++++++++++++++++++++++++++++++++++++++++ > mm/filemap.c | 5 +++ > 2 files changed, 84 insertions(+) > create mode 100644 include/trace/events/filemap.h > > diff --git a/include/trace/events/filemap.h b/include/trace/events/filemap.h > new file mode 100644 > index 0000000..2d36386 > --- /dev/null > +++ b/include/trace/events/filemap.h > @@ -0,0 +1,79 @@ > +#undef TRACE_SYSTEM > +#define TRACE_SYSTEM filemap > + > +#if !defined(_TRACE_FILEMAP_H) || defined(TRACE_HEADER_MULTI_READ) > +#define _TRACE_FILEMAP_H > + > +#include > +#include > +#include > +#include > +#include > +#include > + > +TRACE_EVENT(mm_filemap_delete_from_page_cache, > + > + TP_PROTO(struct page *page), > + > + TP_ARGS(page), > + > + TP_STRUCT__entry( > + __field(struct page *, page) > + __field(unsigned long, i_ino) > + __field(unsigned long, index) > + __field(dev_t, s_dev) > + ), > + > + TP_fast_assign( > + __entry->page = page; > + __entry->i_ino = page->mapping->host->i_ino; > + __entry->index = page->index; > + if (page->mapping->host->i_sb) > + __entry->s_dev = page->mapping->host->i_sb->s_dev; > + else > + __entry->s_dev = page->mapping->host->i_rdev; > + ), > + > + TP_printk("dev %d:%d ino %lx page=%p pfn=%lu ofs=%lu", > + MAJOR(__entry->s_dev), MINOR(__entry->s_dev), > + __entry->i_ino, > + __entry->page, > + page_to_pfn(__entry->page), > + __entry->index << PAGE_SHIFT) > +); > + > +TRACE_EVENT(mm_filemap_add_to_page_cache, > + > + TP_PROTO(struct page *page), > + > + TP_ARGS(page), > + > + TP_STRUCT__entry( > + __field(struct page *, page) > + __field(unsigned long, i_ino) > + __field(unsigned long, index) > + __field(dev_t, s_dev) > + ), > + > + TP_fast_assign( > + __entry->page = page; > + __entry->i_ino = page->mapping->host->i_ino; > + __entry->index = page->index; > + if (page->mapping->host->i_sb) > + __entry->s_dev = page->mapping->host->i_sb->s_dev; > + else > + __entry->s_dev = page->mapping->host->i_rdev; > + ), > + > + TP_printk("dev %d:%d ino %lx page=%p pfn=%lu ofs=%lu", > + MAJOR(__entry->s_dev), MINOR(__entry->s_dev), > + __entry->i_ino, > + __entry->page, > + page_to_pfn(__entry->page), > + __entry->index << PAGE_SHIFT) > +); The above two events are identical. Please use DECLARE_EVENT_CLASS() DEFINE_EVENT() for them. It saves a lot of excess created code. -- Steve > + > +#endif /* _TRACE_FILEMAP_H */ > + > +/* This part must be outside protection */ > +#include > diff --git a/mm/filemap.c b/mm/filemap.c > index e1979fd..6ed13fc 100644 > --- a/mm/filemap.c > +++ b/mm/filemap.c > @@ -35,6 +35,9 @@ > #include > #include "internal.h" > > +#define CREATE_TRACE_POINTS > +#include > + > /* > * FIXME: remove all knowledge of the buffer layer from the core VM > */ > @@ -113,6 +116,7 @@ void __delete_from_page_cache(struct page *page) > { > struct address_space *mapping = page->mapping; > > + trace_mm_filemap_delete_from_page_cache(page); > /* > * if we're uptodate, flush out into the cleancache, otherwise > * invalidate any existing cleancache entries. We can't leave > @@ -463,6 +467,7 @@ int add_to_page_cache_locked(struct page *page, struct address_space *mapping, > if (likely(!error)) { > mapping->nrpages++; > __inc_zone_page_state(page, NR_FILE_PAGES); > + trace_mm_filemap_add_to_page_cache(page); > spin_unlock_irq(&mapping->tree_lock); > } else { > page->mapping = NULL; -- 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