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/xfs_buf_item.c b/fs/xfs/xfs_buf_item.c
index 92af409..a30f7e9 100644
--- a/fs/xfs/xfs_buf_item.c
+++ b/fs/xfs/xfs_buf_item.c
@@ -29,6 +29,7 @@
 #include "xfs_buf_item.h"
 #include "xfs_trans_priv.h"
 #include "xfs_error.h"
+#include "xfs_trace.h"
 
 
 kmem_zone_t	*xfs_buf_item_zone;
@@ -164,7 +165,7 @@
 		 * is the buf log format structure with the
 		 * cancel flag in it.
 		 */
-		xfs_buf_item_trace("SIZE STALE", bip);
+		trace_xfs_buf_item_size_stale(bip);
 		ASSERT(bip->bli_format.blf_flags & XFS_BLI_CANCEL);
 		return 1;
 	}
@@ -206,7 +207,7 @@
 		}
 	}
 
-	xfs_buf_item_trace("SIZE NORM", bip);
+	trace_xfs_buf_item_size(bip);
 	return nvecs;
 }
 
@@ -259,7 +260,7 @@
 		 * is the buf log format structure with the
 		 * cancel flag in it.
 		 */
-		xfs_buf_item_trace("FORMAT STALE", bip);
+		trace_xfs_buf_item_format_stale(bip);
 		ASSERT(bip->bli_format.blf_flags & XFS_BLI_CANCEL);
 		bip->bli_format.blf_size = nvecs;
 		return;
@@ -335,7 +336,7 @@
 	/*
 	 * Check to make sure everything is consistent.
 	 */
-	xfs_buf_item_trace("FORMAT NORM", bip);
+	trace_xfs_buf_item_format(bip);
 	xfs_buf_item_log_check(bip);
 }
 
@@ -355,8 +356,7 @@
 	ASSERT(atomic_read(&bip->bli_refcount) > 0);
 	ASSERT((bip->bli_flags & XFS_BLI_LOGGED) ||
 	       (bip->bli_flags & XFS_BLI_STALE));
-	xfs_buf_item_trace("PIN", bip);
-	xfs_buftrace("XFS_PIN", bp);
+	trace_xfs_buf_item_pin(bip);
 	xfs_bpin(bp);
 }
 
@@ -383,8 +383,7 @@
 	ASSERT(bp != NULL);
 	ASSERT(XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *) == bip);
 	ASSERT(atomic_read(&bip->bli_refcount) > 0);
-	xfs_buf_item_trace("UNPIN", bip);
-	xfs_buftrace("XFS_UNPIN", bp);
+	trace_xfs_buf_item_unpin(bip);
 
 	freed = atomic_dec_and_test(&bip->bli_refcount);
 	ailp = bip->bli_item.li_ailp;
@@ -395,8 +394,8 @@
 		ASSERT(!(XFS_BUF_ISDELAYWRITE(bp)));
 		ASSERT(XFS_BUF_ISSTALE(bp));
 		ASSERT(bip->bli_format.blf_flags & XFS_BLI_CANCEL);
-		xfs_buf_item_trace("UNPIN STALE", bip);
-		xfs_buftrace("XFS_UNPIN STALE", bp);
+		trace_xfs_buf_item_unpin_stale(bip);
+
 		/*
 		 * If we get called here because of an IO error, we may
 		 * or may not have the item on the AIL. xfs_trans_ail_delete()
@@ -440,8 +439,8 @@
 	if ((atomic_read(&bip->bli_refcount) == 1) &&
 	    (bip->bli_flags & XFS_BLI_STALE)) {
 		ASSERT(XFS_BUF_VALUSEMA(bip->bli_buf) <= 0);
-		xfs_buf_item_trace("UNPIN REMOVE", bip);
-		xfs_buftrace("XFS_UNPIN_REMOVE", bp);
+		trace_xfs_buf_item_unpin_stale(bip);
+
 		/*
 		 * yes -- clear the xaction descriptor in-use flag
 		 * and free the chunk if required.  We can safely
@@ -495,7 +494,7 @@
 	XFS_BUF_HOLD(bp);
 
 	ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
-	xfs_buf_item_trace("TRYLOCK SUCCESS", bip);
+	trace_xfs_buf_item_trylock(bip);
 	return XFS_ITEM_SUCCESS;
 }
 
@@ -524,7 +523,6 @@
 	uint		hold;
 
 	bp = bip->bli_buf;
-	xfs_buftrace("XFS_UNLOCK", bp);
 
 	/*
 	 * Clear the buffer's association with this transaction.
@@ -547,7 +545,7 @@
 	 */
 	if (bip->bli_flags & XFS_BLI_STALE) {
 		bip->bli_flags &= ~XFS_BLI_LOGGED;
-		xfs_buf_item_trace("UNLOCK STALE", bip);
+		trace_xfs_buf_item_unlock_stale(bip);
 		ASSERT(bip->bli_format.blf_flags & XFS_BLI_CANCEL);
 		if (!aborted)
 			return;
@@ -574,7 +572,7 @@
 	 * release the buffer at the end of this routine.
 	 */
 	hold = bip->bli_flags & XFS_BLI_HOLD;
-	xfs_buf_item_trace("UNLOCK", bip);
+	trace_xfs_buf_item_unlock(bip);
 
 	/*
 	 * If the buf item isn't tracking any data, free it.
@@ -618,7 +616,8 @@
 	xfs_buf_log_item_t	*bip,
 	xfs_lsn_t		lsn)
 {
-	xfs_buf_item_trace("COMMITTED", bip);
+	trace_xfs_buf_item_committed(bip);
+
 	if ((bip->bli_flags & XFS_BLI_INODE_ALLOC_BUF) &&
 	    (bip->bli_item.li_lsn != 0)) {
 		return bip->bli_item.li_lsn;
@@ -640,7 +639,7 @@
 	xfs_buf_t	*bp;
 
 	ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
-	xfs_buf_item_trace("PUSH", bip);
+	trace_xfs_buf_item_push(bip);
 
 	bp = bip->bli_buf;
 
@@ -738,9 +737,6 @@
 	bip->bli_format.blf_blkno = (__int64_t)XFS_BUF_ADDR(bp);
 	bip->bli_format.blf_len = (ushort)BTOBB(XFS_BUF_COUNT(bp));
 	bip->bli_format.blf_map_size = map_size;
-#ifdef XFS_BLI_TRACE
-	bip->bli_trace = ktrace_alloc(XFS_BLI_TRACE_SIZE, KM_NOFS);
-#endif
 
 #ifdef XFS_TRANS_DEBUG
 	/*
@@ -878,9 +874,6 @@
 	kmem_free(bip->bli_logged);
 #endif /* XFS_TRANS_DEBUG */
 
-#ifdef XFS_BLI_TRACE
-	ktrace_free(bip->bli_trace);
-#endif
 	kmem_zone_free(xfs_buf_item_zone, bip);
 }
 
@@ -897,7 +890,8 @@
 {
 	xfs_buf_log_item_t	*bip;
 
-	xfs_buftrace("XFS_RELSE", bp);
+	trace_xfs_buf_item_relse(bp, _RET_IP_);
+
 	bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t*);
 	XFS_BUF_SET_FSPRIVATE(bp, bip->bli_item.li_bio_list);
 	if ((XFS_BUF_FSPRIVATE(bp, void *) == NULL) &&
@@ -994,7 +988,7 @@
 		if (XFS_FORCED_SHUTDOWN(mp)) {
 			ASSERT(XFS_BUF_TARGET(bp) == mp->m_ddev_targp);
 			XFS_BUF_SUPER_STALE(bp);
-			xfs_buftrace("BUF_IODONE_CB", bp);
+			trace_xfs_buf_item_iodone(bp, _RET_IP_);
 			xfs_buf_do_callbacks(bp, lip);
 			XFS_BUF_SET_FSPRIVATE(bp, NULL);
 			XFS_BUF_CLR_IODONE_FUNC(bp);
@@ -1030,7 +1024,7 @@
 				XFS_BUF_SET_START(bp);
 			}
 			ASSERT(XFS_BUF_IODONE_FUNC(bp));
-			xfs_buftrace("BUF_IODONE ASYNC", bp);
+			trace_xfs_buf_item_iodone_async(bp, _RET_IP_);
 			xfs_buf_relse(bp);
 		} else {
 			/*
@@ -1053,9 +1047,7 @@
 		}
 		return;
 	}
-#ifdef XFSERRORDEBUG
-	xfs_buftrace("XFS BUFCB NOERR", bp);
-#endif
+
 	xfs_buf_do_callbacks(bp, lip);
 	XFS_BUF_SET_FSPRIVATE(bp, NULL);
 	XFS_BUF_CLR_IODONE_FUNC(bp);
@@ -1081,7 +1073,9 @@
 	XFS_BUF_DONE(bp);
 	XFS_BUF_UNDELAYWRITE(bp);
 	XFS_BUF_ERROR(bp,0);
-	xfs_buftrace("BUF_ERROR_RELSE", bp);
+
+	trace_xfs_buf_error_relse(bp, _RET_IP_);
+
 	if (! XFS_FORCED_SHUTDOWN(mp))
 		xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
 	/*
@@ -1128,34 +1122,3 @@
 	xfs_trans_ail_delete(ailp, (xfs_log_item_t *)bip);
 	xfs_buf_item_free(bip);
 }
-
-#if defined(XFS_BLI_TRACE)
-void
-xfs_buf_item_trace(
-	char			*id,
-	xfs_buf_log_item_t	*bip)
-{
-	xfs_buf_t		*bp;
-	ASSERT(bip->bli_trace != NULL);
-
-	bp = bip->bli_buf;
-	ktrace_enter(bip->bli_trace,
-		     (void *)id,
-		     (void *)bip->bli_buf,
-		     (void *)((unsigned long)bip->bli_flags),
-		     (void *)((unsigned long)bip->bli_recur),
-		     (void *)((unsigned long)atomic_read(&bip->bli_refcount)),
-		     (void *)((unsigned long)
-				(0xFFFFFFFF & XFS_BUF_ADDR(bp) >> 32)),
-		     (void *)((unsigned long)(0xFFFFFFFF & XFS_BUF_ADDR(bp))),
-		     (void *)((unsigned long)XFS_BUF_COUNT(bp)),
-		     (void *)((unsigned long)XFS_BUF_BFLAGS(bp)),
-		     XFS_BUF_FSPRIVATE(bp, void *),
-		     XFS_BUF_FSPRIVATE2(bp, void *),
-		     (void *)(unsigned long)XFS_BUF_ISPINNED(bp),
-		     (void *)XFS_BUF_IODONE_FUNC(bp),
-		     (void *)((unsigned long)(XFS_BUF_VALUSEMA(bp))),
-		     (void *)bip->bli_item.li_desc,
-		     (void *)((unsigned long)bip->bli_item.li_flags));
-}
-#endif /* XFS_BLI_TRACE */