From: Dave Chinner Date: Fri, 8 Jan 2016 00:28:35 +0000 (+1100) Subject: xfs: add tracepoints to readpage calls X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=121e213eabad66c0453904d76e3eda193958acbd;p=linux.git xfs: add tracepoints to readpage calls This allows us to see page cache driven readahead in action as it passes through XFS. This helps to understand buffered read throughput problems such as readahead IO IO sizes being too small for the underlying device to reach max throughput. Signed-off-by: Dave Chinner Reviewed-by: Brian Foster Signed-off-by: Dave Chinner --- diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index 29e7e5dd5178e..379c089fb0514 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -1917,6 +1917,7 @@ xfs_vm_readpage( struct file *unused, struct page *page) { + trace_xfs_vm_readpage(page->mapping->host, 1); return mpage_readpage(page, xfs_get_blocks); } @@ -1927,6 +1928,7 @@ xfs_vm_readpages( struct list_head *pages, unsigned nr_pages) { + trace_xfs_vm_readpages(mapping->host, nr_pages); return mpage_readpages(mapping, pages, nr_pages, xfs_get_blocks); } diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h index 877079eb0f8f0..391d797cb53fe 100644 --- a/fs/xfs/xfs_trace.h +++ b/fs/xfs/xfs_trace.h @@ -1222,6 +1222,32 @@ DEFINE_PAGE_EVENT(xfs_writepage); DEFINE_PAGE_EVENT(xfs_releasepage); DEFINE_PAGE_EVENT(xfs_invalidatepage); +DECLARE_EVENT_CLASS(xfs_readpage_class, + TP_PROTO(struct inode *inode, int nr_pages), + TP_ARGS(inode, nr_pages), + TP_STRUCT__entry( + __field(dev_t, dev) + __field(xfs_ino_t, ino) + __field(int, nr_pages) + ), + TP_fast_assign( + __entry->dev = inode->i_sb->s_dev; + __entry->ino = inode->i_ino; + __entry->nr_pages = nr_pages; + ), + TP_printk("dev %d:%d ino 0x%llx nr_pages %d", + MAJOR(__entry->dev), MINOR(__entry->dev), + __entry->ino, + __entry->nr_pages) +) + +#define DEFINE_READPAGE_EVENT(name) \ +DEFINE_EVENT(xfs_readpage_class, name, \ + TP_PROTO(struct inode *inode, int nr_pages), \ + TP_ARGS(inode, nr_pages)) +DEFINE_READPAGE_EVENT(xfs_vm_readpage); +DEFINE_READPAGE_EVENT(xfs_vm_readpages); + DECLARE_EVENT_CLASS(xfs_imap_class, TP_PROTO(struct xfs_inode *ip, xfs_off_t offset, ssize_t count, int type, struct xfs_bmbt_irec *irec),