xfs: event tracing support

Convert the old xfs tracing support that could only be used with the
out of tree kdb and xfsidbg patches to use the generic event tracer.

To use it make sure CONFIG_EVENT_TRACING is enabled and then enable
all xfs trace channels by:

   echo 1 > /sys/kernel/debug/tracing/events/xfs/enable

or alternatively enable single events by just doing the same in one
event subdirectory, e.g.

   echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable

or set more complex filters, etc. In Documentation/trace/events.txt
all this is desctribed in more detail.  To reads the events do a

   cat /sys/kernel/debug/tracing/trace

Compared to the last posting this patch converts the tracing mostly to
the one tracepoint per callsite model that other users of the new
tracing facility also employ.  This allows a very fine-grained control
of the tracing, a cleaner output of the traces and also enables the
perf tool to use each tracepoint as a virtual performance counter,
     allowing us to e.g. count how often certain workloads git various
     spots in XFS.  Take a look at

    http://lwn.net/Articles/346470/

for some examples.

Also the btree tracing isn't included at all yet, as it will require
additional core tracing features not in mainline yet, I plan to
deliver it later.

And the really nice thing about this patch is that it actually removes
many lines of code while adding this nice functionality:

 fs/xfs/Makefile                |    8
 fs/xfs/linux-2.6/xfs_acl.c     |    1
 fs/xfs/linux-2.6/xfs_aops.c    |   52 -
 fs/xfs/linux-2.6/xfs_aops.h    |    2
 fs/xfs/linux-2.6/xfs_buf.c     |  117 +--
 fs/xfs/linux-2.6/xfs_buf.h     |   33
 fs/xfs/linux-2.6/xfs_fs_subr.c |    3
 fs/xfs/linux-2.6/xfs_ioctl.c   |    1
 fs/xfs/linux-2.6/xfs_ioctl32.c |    1
 fs/xfs/linux-2.6/xfs_iops.c    |    1
 fs/xfs/linux-2.6/xfs_linux.h   |    1
 fs/xfs/linux-2.6/xfs_lrw.c     |   87 --
 fs/xfs/linux-2.6/xfs_lrw.h     |   45 -
 fs/xfs/linux-2.6/xfs_super.c   |  104 ---
 fs/xfs/linux-2.6/xfs_super.h   |    7
 fs/xfs/linux-2.6/xfs_sync.c    |    1
 fs/xfs/linux-2.6/xfs_trace.c   |   75 ++
 fs/xfs/linux-2.6/xfs_trace.h   | 1369 +++++++++++++++++++++++++++++++++++++++++
 fs/xfs/linux-2.6/xfs_vnode.h   |    4
 fs/xfs/quota/xfs_dquot.c       |  110 ---
 fs/xfs/quota/xfs_dquot.h       |   21
 fs/xfs/quota/xfs_qm.c          |   40 -
 fs/xfs/quota/xfs_qm_syscalls.c |    4
 fs/xfs/support/ktrace.c        |  323 ---------
 fs/xfs/support/ktrace.h        |   85 --
 fs/xfs/xfs.h                   |   16
 fs/xfs/xfs_ag.h                |   14
 fs/xfs/xfs_alloc.c             |  230 +-----
 fs/xfs/xfs_alloc.h             |   27
 fs/xfs/xfs_alloc_btree.c       |    1
 fs/xfs/xfs_attr.c              |  107 ---
 fs/xfs/xfs_attr.h              |   10
 fs/xfs/xfs_attr_leaf.c         |   14
 fs/xfs/xfs_attr_sf.h           |   40 -
 fs/xfs/xfs_bmap.c              |  507 +++------------
 fs/xfs/xfs_bmap.h              |   49 -
 fs/xfs/xfs_bmap_btree.c        |    6
 fs/xfs/xfs_btree.c             |    5
 fs/xfs/xfs_btree_trace.h       |   17
 fs/xfs/xfs_buf_item.c          |   87 --
 fs/xfs/xfs_buf_item.h          |   20
 fs/xfs/xfs_da_btree.c          |    3
 fs/xfs/xfs_da_btree.h          |    7
 fs/xfs/xfs_dfrag.c             |    2
 fs/xfs/xfs_dir2.c              |    8
 fs/xfs/xfs_dir2_block.c        |   20
 fs/xfs/xfs_dir2_leaf.c         |   21
 fs/xfs/xfs_dir2_node.c         |   27
 fs/xfs/xfs_dir2_sf.c           |   26
 fs/xfs/xfs_dir2_trace.c        |  216 ------
 fs/xfs/xfs_dir2_trace.h        |   72 --
 fs/xfs/xfs_filestream.c        |    8
 fs/xfs/xfs_fsops.c             |    2
 fs/xfs/xfs_iget.c              |  111 ---
 fs/xfs/xfs_inode.c             |   67 --
 fs/xfs/xfs_inode.h             |   76 --
 fs/xfs/xfs_inode_item.c        |    5
 fs/xfs/xfs_iomap.c             |   85 --
 fs/xfs/xfs_iomap.h             |    8
 fs/xfs/xfs_log.c               |  181 +----
 fs/xfs/xfs_log_priv.h          |   20
 fs/xfs/xfs_log_recover.c       |    1
 fs/xfs/xfs_mount.c             |    2
 fs/xfs/xfs_quota.h             |    8
 fs/xfs/xfs_rename.c            |    1
 fs/xfs/xfs_rtalloc.c           |    1
 fs/xfs/xfs_rw.c                |    3
 fs/xfs/xfs_trans.h             |   47 +
 fs/xfs/xfs_trans_buf.c         |   62 -
 fs/xfs/xfs_vnodeops.c          |    8
 70 files changed, 2151 insertions(+), 2592 deletions(-)

Signed-off-by: Christoph Hellwig <[email protected]>
Signed-off-by: Alex Elder <[email protected]>

fs/xfs/Makefile

@@ -26,6 +26,8 @@ endif
 
 obj-$(CONFIG_XFS_FS)		+= xfs.o
 
+xfs-y				+= linux-2.6/xfs_trace.o
+
 xfs-$(CONFIG_XFS_QUOTA)		+= $(addprefix quota/, \
 				   xfs_dquot.o \
 				   xfs_dquot_item.o \
@@ -90,8 +92,7 @@ xfs-y				+= xfs_alloc.o \
 				   xfs_rw.o \
 				   xfs_dmops.o
 
-xfs-$(CONFIG_XFS_TRACE)		+= xfs_btree_trace.o \
-				   xfs_dir2_trace.o
+xfs-$(CONFIG_XFS_TRACE)		+= xfs_btree_trace.o
 
 # Objects in linux/
 xfs-y				+= $(addprefix $(XFS_LINUX)/, \
@@ -113,6 +114,3 @@ xfs-y				+= $(addprefix $(XFS_LINUX)/, \
 xfs-y				+= $(addprefix support/, \
 				   debug.o \
 				   uuid.o)
-
-xfs-$(CONFIG_XFS_TRACE)		+= support/ktrace.o
-

fs/xfs/linux-2.6/xfs_acl.c

@@ -21,6 +21,7 @@
 #include "xfs_bmap_btree.h"
 #include "xfs_inode.h"
 #include "xfs_vnodeops.h"
+#include "xfs_trace.h"
 #include <linux/xattr.h>
 #include <linux/posix_acl_xattr.h>
 

fs/xfs/linux-2.6/xfs_aops.c

@@ -38,6 +38,7 @@
 #include "xfs_rw.h"
 #include "xfs_iomap.h"
 #include "xfs_vnodeops.h"
+#include "xfs_trace.h"
 #include <linux/mpage.h>
 #include <linux/pagevec.h>
 #include <linux/writeback.h>
@@ -76,7 +77,7 @@ xfs_ioend_wake(
 		wake_up(to_ioend_wq(ip));
 }
 
-STATIC void
+void
 xfs_count_page_state(
 	struct page		*page,
 	int			*delalloc,
@@ -98,48 +99,6 @@ xfs_count_page_state(
 	} while ((bh = bh->b_this_page) != head);
 }
 
-#if defined(XFS_RW_TRACE)
-void
-xfs_page_trace(
-	int		tag,
-	struct inode	*inode,
-	struct page	*page,
-	unsigned long	pgoff)
-{
-	xfs_inode_t	*ip;
-	loff_t		isize = i_size_read(inode);
-	loff_t		offset = page_offset(page);
-	int		delalloc = -1, unmapped = -1, unwritten = -1;
-
-	if (page_has_buffers(page))
-		xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
-
-	ip = XFS_I(inode);
-	if (!ip->i_rwtrace)
-		return;
-
-	ktrace_enter(ip->i_rwtrace,
-		(void *)((unsigned long)tag),
-		(void *)ip,
-		(void *)inode,
-		(void *)page,
-		(void *)pgoff,
-		(void *)((unsigned long)((ip->i_d.di_size >> 32) & 0xffffffff)),
-		(void *)((unsigned long)(ip->i_d.di_size & 0xffffffff)),
-		(void *)((unsigned long)((isize >> 32) & 0xffffffff)),
-		(void *)((unsigned long)(isize & 0xffffffff)),
-		(void *)((unsigned long)((offset >> 32) & 0xffffffff)),
-		(void *)((unsigned long)(offset & 0xffffffff)),
-		(void *)((unsigned long)delalloc),
-		(void *)((unsigned long)unmapped),
-		(void *)((unsigned long)unwritten),
-		(void *)((unsigned long)current_pid()),
-		(void *)NULL);
-}
-#else
-#define xfs_page_trace(tag, inode, page, pgoff)
-#endif
-
 STATIC struct block_device *
 xfs_find_bdev_for_inode(
 	struct xfs_inode	*ip)
@@ -1202,7 +1161,7 @@ xfs_vm_writepage(
 	int			delalloc, unmapped, unwritten;
 	struct inode		*inode = page->mapping->host;
 
-	xfs_page_trace(XFS_WRITEPAGE_ENTER, inode, page, 0);
+	trace_xfs_writepage(inode, page, 0);
 
 	/*
 	 * We need a transaction if:
@@ -1307,7 +1266,7 @@ xfs_vm_releasepage(
 		.nr_to_write = 1,
 	};
 
-	xfs_page_trace(XFS_RELEASEPAGE_ENTER, inode, page, 0);
+	trace_xfs_releasepage(inode, page, 0);
 
 	if (!page_has_buffers(page))
 		return 0;
@@ -1587,8 +1546,7 @@ xfs_vm_invalidatepage(
 	struct page		*page,
 	unsigned long		offset)
 {
-	xfs_page_trace(XFS_INVALIDPAGE_ENTER,
-			page->mapping->host, page, offset);
+	trace_xfs_invalidatepage(page->mapping->host, page, offset);
 	block_invalidatepage(page, offset);
 }
 

fs/xfs/linux-2.6/xfs_aops.h

@@ -45,4 +45,6 @@ extern int xfs_get_blocks(struct inode *, sector_t, struct buffer_head *, int);
 extern void xfs_ioend_init(void);
 extern void xfs_ioend_wait(struct xfs_inode *);
 
+extern void xfs_count_page_state(struct page *, int *, int *, int *);
+
 #endif /* __XFS_AOPS_H__ */