From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx104.postini.com [74.125.245.104]) by kanga.kvack.org (Postfix) with SMTP id E95BB6B004D for ; Fri, 23 Nov 2012 18:34:20 -0500 (EST) From: Robert Jarzmik Subject: [PATCH v3] mm: trace filemap add and del Date: Sat, 24 Nov 2012 00:34:06 +0100 Message-Id: <1353713646-30362-1-git-send-email-robert.jarzmik@free.fr> In-Reply-To: <1353679819-6989-1-git-send-email-robert.jarzmik@free.fr> References: <1353679819-6989-1-git-send-email-robert.jarzmik@free.fr> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton , Dave Chinner , Hugh Dickins Cc: linux-mm@kvack.org, 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 --- Since V1: - included Andrew's comments - included Dave's comment - fixed according to Hugh's comment Since V2: - amended inode print to hexadecimal format --- 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) +); + +#endif /* _TRACE_FILEMAP_H */ + +/* This part must be outside protection */ +#include diff --git a/mm/filemap.c b/mm/filemap.c index 83efee7..1ee7cf6 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; -- 1.7.10.4 -- 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