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 <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
diff --git a/fs/xfs/linux-2.6/xfs_lrw.c b/fs/xfs/linux-2.6/xfs_lrw.c
index 1bf47f2..0d32457 100644
--- a/fs/xfs/linux-2.6/xfs_lrw.c
+++ b/fs/xfs/linux-2.6/xfs_lrw.c
@@ -48,73 +48,12 @@
 #include "xfs_utils.h"
 #include "xfs_iomap.h"
 #include "xfs_vnodeops.h"
+#include "xfs_trace.h"
 
 #include <linux/capability.h>
 #include <linux/writeback.h>
 
 
-#if defined(XFS_RW_TRACE)
-void
-xfs_rw_enter_trace(
-	int			tag,
-	xfs_inode_t		*ip,
-	void			*data,
-	size_t			segs,
-	loff_t			offset,
-	int			ioflags)
-{
-	if (ip->i_rwtrace == NULL)
-		return;
-	ktrace_enter(ip->i_rwtrace,
-		(void *)(unsigned long)tag,
-		(void *)ip,
-		(void *)((unsigned long)((ip->i_d.di_size >> 32) & 0xffffffff)),
-		(void *)((unsigned long)(ip->i_d.di_size & 0xffffffff)),
-		(void *)data,
-		(void *)((unsigned long)segs),
-		(void *)((unsigned long)((offset >> 32) & 0xffffffff)),
-		(void *)((unsigned long)(offset & 0xffffffff)),
-		(void *)((unsigned long)ioflags),
-		(void *)((unsigned long)((ip->i_new_size >> 32) & 0xffffffff)),
-		(void *)((unsigned long)(ip->i_new_size & 0xffffffff)),
-		(void *)((unsigned long)current_pid()),
-		(void *)NULL,
-		(void *)NULL,
-		(void *)NULL,
-		(void *)NULL);
-}
-
-void
-xfs_inval_cached_trace(
-	xfs_inode_t	*ip,
-	xfs_off_t	offset,
-	xfs_off_t	len,
-	xfs_off_t	first,
-	xfs_off_t	last)
-{
-
-	if (ip->i_rwtrace == NULL)
-		return;
-	ktrace_enter(ip->i_rwtrace,
-		(void *)(__psint_t)XFS_INVAL_CACHED,
-		(void *)ip,
-		(void *)((unsigned long)((offset >> 32) & 0xffffffff)),
-		(void *)((unsigned long)(offset & 0xffffffff)),
-		(void *)((unsigned long)((len >> 32) & 0xffffffff)),
-		(void *)((unsigned long)(len & 0xffffffff)),
-		(void *)((unsigned long)((first >> 32) & 0xffffffff)),
-		(void *)((unsigned long)(first & 0xffffffff)),
-		(void *)((unsigned long)((last >> 32) & 0xffffffff)),
-		(void *)((unsigned long)(last & 0xffffffff)),
-		(void *)((unsigned long)current_pid()),
-		(void *)NULL,
-		(void *)NULL,
-		(void *)NULL,
-		(void *)NULL,
-		(void *)NULL);
-}
-#endif
-
 /*
  *	xfs_iozero
  *
@@ -250,8 +189,7 @@
 		}
 	}
 
-	xfs_rw_enter_trace(XFS_READ_ENTER, ip,
-				(void *)iovp, segs, *offset, ioflags);
+	trace_xfs_file_read(ip, size, *offset, ioflags);
 
 	iocb->ki_pos = *offset;
 	ret = generic_file_aio_read(iocb, iovp, segs, *offset);
@@ -292,8 +230,9 @@
 			return -error;
 		}
 	}
-	xfs_rw_enter_trace(XFS_SPLICE_READ_ENTER, ip,
-			   pipe, count, *ppos, ioflags);
+
+	trace_xfs_file_splice_read(ip, count, *ppos, ioflags);
+
 	ret = generic_file_splice_read(infilp, ppos, pipe, count, flags);
 	if (ret > 0)
 		XFS_STATS_ADD(xs_read_bytes, ret);
@@ -342,8 +281,8 @@
 		ip->i_new_size = new_size;
 	xfs_iunlock(ip, XFS_ILOCK_EXCL);
 
-	xfs_rw_enter_trace(XFS_SPLICE_WRITE_ENTER, ip,
-			   pipe, count, *ppos, ioflags);
+	trace_xfs_file_splice_write(ip, count, *ppos, ioflags);
+
 	ret = generic_file_splice_write(pipe, outfilp, ppos, count, flags);
 	if (ret > 0)
 		XFS_STATS_ADD(xs_write_bytes, ret);
@@ -710,8 +649,6 @@
 	if ((ioflags & IO_ISDIRECT)) {
 		if (mapping->nrpages) {
 			WARN_ON(need_i_mutex == 0);
-			xfs_inval_cached_trace(xip, pos, -1,
-					(pos & PAGE_CACHE_MASK), -1);
 			error = xfs_flushinval_pages(xip,
 					(pos & PAGE_CACHE_MASK),
 					-1, FI_REMAPF_LOCKED);
@@ -728,8 +665,7 @@
 			need_i_mutex = 0;
 		}
 
- 		xfs_rw_enter_trace(XFS_DIOWR_ENTER, xip, (void *)iovp, segs,
-				*offset, ioflags);
+		trace_xfs_file_direct_write(xip, count, *offset, ioflags);
 		ret = generic_file_direct_write(iocb, iovp,
 				&segs, pos, offset, count, ocount);
 
@@ -752,8 +688,7 @@
 		ssize_t ret2 = 0;
 
 write_retry:
-		xfs_rw_enter_trace(XFS_WRITE_ENTER, xip, (void *)iovp, segs,
-				*offset, ioflags);
+		trace_xfs_file_buffered_write(xip, count, *offset, ioflags);
 		ret2 = generic_file_buffered_write(iocb, iovp, segs,
 				pos, offset, count, ret);
 		/*
@@ -858,7 +793,7 @@
 xfs_bdstrat_cb(struct xfs_buf *bp)
 {
 	if (XFS_FORCED_SHUTDOWN(bp->b_mount)) {
-		xfs_buftrace("XFS__BDSTRAT IOERROR", bp);
+		trace_xfs_bdstrat_shut(bp, _RET_IP_);
 		/*
 		 * Metadata write that didn't get logged but
 		 * written delayed anyway. These aren't associated
@@ -891,7 +826,7 @@
 		return;
 	}
 
-	xfs_buftrace("XFSBDSTRAT IOERROR", bp);
+	trace_xfs_bdstrat_shut(bp, _RET_IP_);
 	xfs_bioerror_relse(bp);
 }