From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx114.postini.com [74.125.245.114]) by kanga.kvack.org (Postfix) with SMTP id 177D66B005D for ; Tue, 20 Nov 2012 13:50:46 -0500 (EST) From: Robert Jarzmik Subject: [PATCH] mm: trace filemap add and del Date: Tue, 20 Nov 2012 19:50:31 +0100 Message-Id: <1353437431-25134-1-git-send-email-robert.jarzmik@free.fr> Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Robert Jarzmik 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 --- 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..a8319e2 --- /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_no) + __field(unsigned long, pageofs) + __field(dev_t, s_dev) + ), + + TP_fast_assign( + __entry->page = page; + __entry->i_no = page->mapping->host->i_ino; + __entry->pageofs = 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("page=%p pfn=%lu blk=%d:%d inode+ofs=%lu+%lu", + __entry->page, + page_to_pfn(__entry->page), + MAJOR(__entry->s_dev), MINOR(__entry->s_dev), + __entry->i_no, + __entry->pageofs << 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_no) + __field(unsigned long, pageofs) + __field(dev_t, s_dev) + ), + + TP_fast_assign( + __entry->page = page; + __entry->i_no = page->mapping->host->i_ino; + __entry->pageofs = 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("page=%p pfn=%lu blk=%d:%d inode+ofs=%lu+%lu", + __entry->page, + page_to_pfn(__entry->page), + MAJOR(__entry->s_dev), MINOR(__entry->s_dev), + __entry->i_no, + __entry->pageofs) +); + +#endif /* _TRACE_FILEMAP_H */ + +/* This part must be outside protection */ +#include diff --git a/mm/filemap.c b/mm/filemap.c index 3843445..9753b7c 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 @@ -467,6 +471,7 @@ int add_to_page_cache_locked(struct page *page, struct address_space *mapping, } else { page->mapping = NULL; /* Leave page->index set: truncation relies upon it */ + trace_mm_filemap_add_to_page_cache(page); spin_unlock_irq(&mapping->tree_lock); mem_cgroup_uncharge_cache_page(page); page_cache_release(page); -- 1.7.9.5 -- 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