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/quota/xfs_qm.c b/fs/xfs/quota/xfs_qm.c
index 45b1bfe..9e627a8 100644
--- a/fs/xfs/quota/xfs_qm.c
+++ b/fs/xfs/quota/xfs_qm.c
@@ -47,6 +47,7 @@
 #include "xfs_trans_space.h"
 #include "xfs_utils.h"
 #include "xfs_qm.h"
+#include "xfs_trace.h"
 
 /*
  * The global quota manager. There is only one of these for the entire
@@ -453,7 +454,7 @@
 			xfs_dqunlock(dqp);
 			continue;
 		}
-		xfs_dqtrace_entry(dqp, "FLUSHALL: DQDIRTY");
+
 		/* XXX a sentinel would be better */
 		recl = XFS_QI_MPLRECLAIMS(mp);
 		if (!xfs_dqflock_nowait(dqp)) {
@@ -651,7 +652,7 @@
 	 */
 	dqp = *IO_idqpp;
 	if (dqp) {
-		xfs_dqtrace_entry(dqp, "DQATTACH: found in ip");
+		trace_xfs_dqattach_found(dqp);
 		return 0;
 	}
 
@@ -704,7 +705,7 @@
 	if (error)
 		return error;
 
-	xfs_dqtrace_entry(dqp, "DQATTACH: found by dqget");
+	trace_xfs_dqattach_get(dqp);
 
 	/*
 	 * dqget may have dropped and re-acquired the ilock, but it guarantees
@@ -890,15 +891,15 @@
 	if (!(ip->i_udquot || ip->i_gdquot))
 		return;
 
+	trace_xfs_dquot_dqdetach(ip);
+
 	ASSERT(ip->i_ino != ip->i_mount->m_sb.sb_uquotino);
 	ASSERT(ip->i_ino != ip->i_mount->m_sb.sb_gquotino);
 	if (ip->i_udquot) {
-		xfs_dqtrace_entry_ino(ip->i_udquot, "DQDETTACH", ip);
 		xfs_qm_dqrele(ip->i_udquot);
 		ip->i_udquot = NULL;
 	}
 	if (ip->i_gdquot) {
-		xfs_dqtrace_entry_ino(ip->i_gdquot, "DQDETTACH", ip);
 		xfs_qm_dqrele(ip->i_gdquot);
 		ip->i_gdquot = NULL;
 	}
@@ -977,7 +978,6 @@
 		 * across a disk write
 		 */
 		xfs_qm_mplist_unlock(mp);
-		xfs_dqtrace_entry(dqp, "XQM_SYNC: DQFLUSH");
 		error = xfs_qm_dqflush(dqp, flush_flags);
 		xfs_dqunlock(dqp);
 		if (error && XFS_FORCED_SHUTDOWN(mp))
@@ -1350,7 +1350,8 @@
 	xfs_disk_dquot_t	*ddq;
 	int			j;
 
-	xfs_buftrace("RESET DQUOTS", bp);
+	trace_xfs_reset_dqcounts(bp, _RET_IP_);
+
 	/*
 	 * Reset all counters and timers. They'll be
 	 * started afresh by xfs_qm_quotacheck.
@@ -1543,7 +1544,9 @@
 	xfs_qcnt_t		rtblks)
 {
 	ASSERT(XFS_DQ_IS_LOCKED(dqp));
-	xfs_dqtrace_entry(dqp, "QCHECK DQADJUST");
+
+	trace_xfs_dqadjust(dqp);
+
 	/*
 	 * Adjust the inode count and the block count to reflect this inode's
 	 * resource usage.
@@ -1994,7 +1997,9 @@
 		 */
 		if (XFS_DQ_IS_DIRTY(dqp)) {
 			int	error;
-			xfs_dqtrace_entry(dqp, "DQSHAKE: DQDIRTY");
+
+			trace_xfs_dqshake_dirty(dqp);
+
 			/*
 			 * We flush it delayed write, so don't bother
 			 * releasing the mplock.
@@ -2038,7 +2043,9 @@
 				return nreclaimed;
 			goto tryagain;
 		}
-		xfs_dqtrace_entry(dqp, "DQSHAKE: UNLINKING");
+
+		trace_xfs_dqshake_unlink(dqp);
+
 #ifdef QUOTADEBUG
 		cmn_err(CE_DEBUG, "Shake 0x%p, ID 0x%x\n",
 			dqp, be32_to_cpu(dqp->q_core.d_id));
@@ -2125,7 +2132,9 @@
 		 */
 		if (dqp->dq_flags & XFS_DQ_WANT) {
 			ASSERT(! (dqp->dq_flags & XFS_DQ_INACTIVE));
-			xfs_dqtrace_entry(dqp, "DQRECLAIM: DQWANT");
+
+			trace_xfs_dqreclaim_want(dqp);
+
 			xfs_dqunlock(dqp);
 			xfs_qm_freelist_unlock(xfs_Gqm);
 			if (++restarts >= XFS_QM_RECLAIM_MAX_RESTARTS)
@@ -2171,7 +2180,9 @@
 		 */
 		if (XFS_DQ_IS_DIRTY(dqp)) {
 			int	error;
-			xfs_dqtrace_entry(dqp, "DQRECLAIM: DQDIRTY");
+
+			trace_xfs_dqreclaim_dirty(dqp);
+
 			/*
 			 * We flush it delayed write, so don't bother
 			 * releasing the freelist lock.
@@ -2194,8 +2205,9 @@
 		if (!mutex_trylock(&dqp->q_hash->qh_lock))
 			goto mplistunlock;
 
+		trace_xfs_dqreclaim_unlink(dqp);
+
 		ASSERT(dqp->q_nrefs == 0);
-		xfs_dqtrace_entry(dqp, "DQRECLAIM: UNLINKING");
 		XQM_MPLIST_REMOVE(&(XFS_QI_MPL_LIST(dqp->q_mount)), dqp);
 		XQM_HASHLIST_REMOVE(dqp->q_hash, dqp);
 		XQM_FREELIST_REMOVE(dqp);
@@ -2430,7 +2442,7 @@
 		}
 	}
 	if (uq)
-		xfs_dqtrace_entry_ino(uq, "DQALLOC", ip);
+		trace_xfs_dquot_dqalloc(ip);
 
 	xfs_iunlock(ip, lockflags);
 	if (O_udqpp)