Hi Kim, > -----Original Message----- > From: Jaegeuk Kim [mailto:jaegeuk.kim@xxxxxxxxxxx] > Sent: Wednesday, May 07, 2014 8:30 AM > To: Chao Yu > Cc: linux-f2fs-devel@xxxxxxxxxxxxxxxxxxxxx; linux-fsdevel@xxxxxxxxxxxxxxx; > linux-kernel@xxxxxxxxxxxxxxx > Subject: Re: [f2fs-dev][PATCH 6/6] f2fs: add a tracepoint for f2fs_read_data_pages > > Hi Chao, > > 2014-05-06 (화), 16:54 +0800, Chao Yu: > > This patch adds a tracepoint for f2fs_read_data_pages to trace when pages are > > readahead by VFS. > > > > Signed-off-by: Chao Yu <chao2.yu@xxxxxxxxxxx> > > --- > > fs/f2fs/data.c | 3 +++ > > include/trace/events/f2fs.h | 26 ++++++++++++++++++++++++++ > > 2 files changed, 29 insertions(+) > > > > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > > index 8c250a5..f2d1e8a 100644 > > --- a/fs/f2fs/data.c > > +++ b/fs/f2fs/data.c > > @@ -729,6 +729,9 @@ static int f2fs_read_data_pages(struct file *file, > > struct list_head *pages, unsigned nr_pages) > > { > > struct inode *inode = file->f_mapping->host; > > + struct page *page = list_entry(pages->prev, struct page, lru); > > IMO, it needs to avoid the above line. Maybe it’s not safe to access page directly in lru list here. Let's ignore this patch. Thanks. > Thanks, > > > + > > + trace_f2fs_readpages(inode, page, nr_pages); > > > > /* If the file has inline data, skip readpages */ > > if (f2fs_has_inline_data(inode)) > > diff --git a/include/trace/events/f2fs.h b/include/trace/events/f2fs.h > > index b983990..7fbaaaa 100644 > > --- a/include/trace/events/f2fs.h > > +++ b/include/trace/events/f2fs.h > > @@ -847,6 +847,32 @@ TRACE_EVENT(f2fs_writepages, > > __entry->for_sync) > > ); > > > > +TRACE_EVENT(f2fs_readpages, > > + > > + TP_PROTO(struct inode *inode, struct page *page, unsigned int nrpage), > > + > > + TP_ARGS(inode, page, nrpage), > > + > > + TP_STRUCT__entry( > > + __field(dev_t, dev) > > + __field(ino_t, ino) > > + __field(pgoff_t, start) > > + __field(unsigned int, nrpage) > > + ), > > + > > + TP_fast_assign( > > + __entry->dev = inode->i_sb->s_dev; > > + __entry->ino = inode->i_ino; > > + __entry->start = page->index; > > + __entry->nrpage = nrpage; > > + ), > > + > > + TP_printk("dev = (%d,%d), ino = %lu, start = %lu nrpage = %u", > > + show_dev_ino(__entry), > > + (unsigned long)__entry->start, > > + __entry->nrpage) > > +); > > + > > TRACE_EVENT(f2fs_submit_page_mbio, > > > > TP_PROTO(struct page *page, int rw, int type, block_t blk_addr), > > -- > Jaegeuk Kim > Samsung -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
