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>

1 files changed, 31 insertions, 79 deletions

diff --git a/fs/xfs/quota/xfs_dquot.c b/fs/xfs/quota/xfs_dquot.c
index 2f3f2229..d7c7eea 100644
--- a/fs/xfs/quota/xfs_dquot.c
+++ b/fs/xfs/quota/xfs_dquot.c
@@ -47,6 +47,7 @@
 #include "xfs_trans_space.h"
 #include "xfs_trans_priv.h"
 #include "xfs_qm.h"
+#include "xfs_trace.h"
 
 
 /*
@@ -112,10 +113,7 @@ xfs_qm_dqinit(
 		init_completion(&dqp->q_flush);
 		complete(&dqp->q_flush);
 
-#ifdef XFS_DQUOT_TRACE
-		dqp->q_trace = ktrace_alloc(DQUOT_TRACE_SIZE, KM_NOFS);
-		xfs_dqtrace_entry(dqp, "DQINIT");
-#endif
+		trace_xfs_dqinit(dqp);
 	} else {
 		/*
 		 * Only the q_core portion was zeroed in dqreclaim_one().
@@ -136,10 +134,7 @@ xfs_qm_dqinit(
 		 dqp->q_hash = NULL;
 		 ASSERT(dqp->dq_flnext == dqp->dq_flprev);
 
-#ifdef XFS_DQUOT_TRACE
-		 ASSERT(dqp->q_trace);
-		 xfs_dqtrace_entry(dqp, "DQRECLAIMED_INIT");
-#endif
+		trace_xfs_dqreuse(dqp);
 	}
 
 	/*
@@ -167,13 +162,8 @@ xfs_qm_dqdestroy(
 
 	mutex_destroy(&dqp->q_qlock);
 	sv_destroy(&dqp->q_pinwait);
-
-#ifdef XFS_DQUOT_TRACE
-	if (dqp->q_trace)
-	     ktrace_free(dqp->q_trace);
-	dqp->q_trace = NULL;
-#endif
 	kmem_zone_free(xfs_Gqm->qm_dqzone, dqp);
+
 	atomic_dec(&xfs_Gqm->qm_totaldquots);
 }
 
@@ -195,49 +185,6 @@ xfs_qm_dqinit_core(
 	d->dd_diskdq.d_flags = type;
 }
 
-
-#ifdef XFS_DQUOT_TRACE
-/*
- * Dquot tracing for debugging.
- */
-/* ARGSUSED */
-void
-__xfs_dqtrace_entry(
-	xfs_dquot_t	*dqp,
-	char		*func,
-	void		*retaddr,
-	xfs_inode_t	*ip)
-{
-	xfs_dquot_t	*udqp = NULL;
-	xfs_ino_t	ino = 0;
-
-	ASSERT(dqp->q_trace);
-	if (ip) {
-		ino = ip->i_ino;
-		udqp = ip->i_udquot;
-	}
-	ktrace_enter(dqp->q_trace,
-		     (void *)(__psint_t)DQUOT_KTRACE_ENTRY,
-		     (void *)func,
-		     (void *)(__psint_t)dqp->q_nrefs,
-		     (void *)(__psint_t)dqp->dq_flags,
-		     (void *)(__psint_t)dqp->q_res_bcount,
-		     (void *)(__psint_t)be64_to_cpu(dqp->q_core.d_bcount),
-		     (void *)(__psint_t)be64_to_cpu(dqp->q_core.d_icount),
-		     (void *)(__psint_t)be64_to_cpu(dqp->q_core.d_blk_hardlimit),
-		     (void *)(__psint_t)be64_to_cpu(dqp->q_core.d_blk_softlimit),
-		     (void *)(__psint_t)be64_to_cpu(dqp->q_core.d_ino_hardlimit),
-		     (void *)(__psint_t)be64_to_cpu(dqp->q_core.d_ino_softlimit),
-		     (void *)(__psint_t)be32_to_cpu(dqp->q_core.d_id),
-		     (void *)(__psint_t)current_pid(),
-		     (void *)(__psint_t)ino,
-		     (void *)(__psint_t)retaddr,
-		     (void *)(__psint_t)udqp);
-	return;
-}
-#endif
-
-
 /*
  * If default limits are in force, push them into the dquot now.
  * We overwrite the dquot limits only if they are zero and this
@@ -425,7 +372,8 @@ xfs_qm_dqalloc(
 	xfs_trans_t	*tp = *tpp;
 
 	ASSERT(tp != NULL);
-	xfs_dqtrace_entry(dqp, "DQALLOC");
+
+	trace_xfs_dqalloc(dqp);
 
 	/*
 	 * Initialize the bmap freelist prior to calling bmapi code.
@@ -612,7 +560,8 @@ xfs_qm_dqtobp(
 	 * (in which case we already have the buf).
 	 */
 	if (! newdquot) {
-		xfs_dqtrace_entry(dqp, "DQTOBP READBUF");
+		trace_xfs_dqtobp_read(dqp);
+
 		if ((error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
 					       dqp->q_blkno,
 					       XFS_QI_DQCHUNKLEN(mp),
@@ -670,11 +619,12 @@ xfs_qm_dqread(
 
 	ASSERT(tpp);
 
+	trace_xfs_dqread(dqp);
+
 	/*
 	 * get a pointer to the on-disk dquot and the buffer containing it
 	 * dqp already knows its own type (GROUP/USER).
 	 */
-	xfs_dqtrace_entry(dqp, "DQREAD");
 	if ((error = xfs_qm_dqtobp(tpp, dqp, &ddqp, &bp, flags))) {
 		return (error);
 	}
@@ -763,7 +713,7 @@ xfs_qm_idtodq(
 		 * or if the dquot didn't exist on disk and we ask to
 		 * allocate (ENOENT).
 		 */
-		xfs_dqtrace_entry(dqp, "DQREAD FAIL");
+		trace_xfs_dqread_fail(dqp);
 		cancelflags |= XFS_TRANS_ABORT;
 		goto error0;
 	}
@@ -817,7 +767,8 @@ xfs_qm_dqlookup(
 		 * id can't be modified without the hashlock anyway.
 		 */
 		if (be32_to_cpu(dqp->q_core.d_id) == id && dqp->q_mount == mp) {
-			xfs_dqtrace_entry(dqp, "DQFOUND BY LOOKUP");
+			trace_xfs_dqlookup_found(dqp);
+
 			/*
 			 * All in core dquots must be on the dqlist of mp
 			 */
@@ -827,7 +778,7 @@ xfs_qm_dqlookup(
 			if (dqp->q_nrefs == 0) {
 				ASSERT (XFS_DQ_IS_ON_FREELIST(dqp));
 				if (! xfs_qm_freelist_lock_nowait(xfs_Gqm)) {
-					xfs_dqtrace_entry(dqp, "DQLOOKUP: WANT");
+					trace_xfs_dqlookup_want(dqp);
 
 					/*
 					 * We may have raced with dqreclaim_one()
@@ -857,8 +808,7 @@ xfs_qm_dqlookup(
 					/*
 					 * take it off the freelist
 					 */
-					xfs_dqtrace_entry(dqp,
-							"DQLOOKUP: TAKEOFF FL");
+					trace_xfs_dqlookup_freelist(dqp);
 					XQM_FREELIST_REMOVE(dqp);
 					/* xfs_qm_freelist_print(&(xfs_Gqm->
 							qm_dqfreelist),
@@ -878,8 +828,7 @@ xfs_qm_dqlookup(
 			 */
 			ASSERT(mutex_is_locked(&qh->qh_lock));
 			if (dqp->HL_PREVP != &qh->qh_next) {
-				xfs_dqtrace_entry(dqp,
-						  "DQLOOKUP: HASH MOVETOFRONT");
+				trace_xfs_dqlookup_move(dqp);
 				if ((d = dqp->HL_NEXT))
 					d->HL_PREVP = dqp->HL_PREVP;
 				*(dqp->HL_PREVP) = d;
@@ -889,7 +838,7 @@ xfs_qm_dqlookup(
 				dqp->HL_PREVP = &qh->qh_next;
 				qh->qh_next = dqp;
 			}
-			xfs_dqtrace_entry(dqp, "LOOKUP END");
+			trace_xfs_dqlookup_done(dqp);
 			*O_dqpp = dqp;
 			ASSERT(mutex_is_locked(&qh->qh_lock));
 			return (0);
@@ -971,7 +920,7 @@ xfs_qm_dqget(
 		ASSERT(*O_dqpp);
 		ASSERT(XFS_DQ_IS_LOCKED(*O_dqpp));
 		mutex_unlock(&h->qh_lock);
-		xfs_dqtrace_entry(*O_dqpp, "DQGET DONE (FROM CACHE)");
+		trace_xfs_dqget_hit(*O_dqpp);
 		return (0);	/* success */
 	}
 	XQM_STATS_INC(xqmstats.xs_qm_dqcachemisses);
@@ -1104,7 +1053,7 @@ xfs_qm_dqget(
 	mutex_unlock(&h->qh_lock);
  dqret:
 	ASSERT((ip == NULL) || xfs_isilocked(ip, XFS_ILOCK_EXCL));
-	xfs_dqtrace_entry(dqp, "DQGET DONE");
+	trace_xfs_dqget_miss(dqp);
 	*O_dqpp = dqp;
 	return (0);
 }
@@ -1124,7 +1073,8 @@ xfs_qm_dqput(
 
 	ASSERT(dqp->q_nrefs > 0);
 	ASSERT(XFS_DQ_IS_LOCKED(dqp));
-	xfs_dqtrace_entry(dqp, "DQPUT");
+
+	trace_xfs_dqput(dqp);
 
 	if (dqp->q_nrefs != 1) {
 		dqp->q_nrefs--;
@@ -1137,7 +1087,7 @@ xfs_qm_dqput(
 	 * in the right order; but try to get it out-of-order first
 	 */
 	if (! xfs_qm_freelist_lock_nowait(xfs_Gqm)) {
-		xfs_dqtrace_entry(dqp, "DQPUT: FLLOCK-WAIT");
+		trace_xfs_dqput_wait(dqp);
 		xfs_dqunlock(dqp);
 		xfs_qm_freelist_lock(xfs_Gqm);
 		xfs_dqlock(dqp);
@@ -1148,7 +1098,8 @@ xfs_qm_dqput(
 
 		/* We can't depend on nrefs being == 1 here */
 		if (--dqp->q_nrefs == 0) {
-			xfs_dqtrace_entry(dqp, "DQPUT: ON FREELIST");
+			trace_xfs_dqput_free(dqp);
+
 			/*
 			 * insert at end of the freelist.
 			 */
@@ -1196,7 +1147,7 @@ xfs_qm_dqrele(
 	if (!dqp)
 		return;
 
-	xfs_dqtrace_entry(dqp, "DQRELE");
+	trace_xfs_dqrele(dqp);
 
 	xfs_dqlock(dqp);
 	/*
@@ -1229,7 +1180,7 @@ xfs_qm_dqflush(
 
 	ASSERT(XFS_DQ_IS_LOCKED(dqp));
 	ASSERT(!completion_done(&dqp->q_flush));
-	xfs_dqtrace_entry(dqp, "DQFLUSH");
+	trace_xfs_dqflush(dqp);
 
 	/*
 	 * If not dirty, or it's pinned and we are not supposed to
@@ -1259,7 +1210,6 @@ xfs_qm_dqflush(
 	 * the ondisk-dquot has already been allocated for.
 	 */
 	if ((error = xfs_qm_dqtobp(NULL, dqp, &ddqp, &bp, XFS_QMOPT_DOWARN))) {
-		xfs_dqtrace_entry(dqp, "DQTOBP FAIL");
 		ASSERT(error != ENOENT);
 		/*
 		 * Quotas could have gotten turned off (ESRCH)
@@ -1297,7 +1247,7 @@ xfs_qm_dqflush(
 	 * get stuck waiting in the write for too long.
 	 */
 	if (XFS_BUF_ISPINNED(bp)) {
-		xfs_dqtrace_entry(dqp, "DQFLUSH LOG FORCE");
+		trace_xfs_dqflush_force(dqp);
 		xfs_log_force(mp, (xfs_lsn_t)0, XFS_LOG_FORCE);
 	}
 
@@ -1308,7 +1258,9 @@ xfs_qm_dqflush(
 	} else {
 		error = xfs_bwrite(mp, bp);
 	}
-	xfs_dqtrace_entry(dqp, "DQFLUSH END");
+
+	trace_xfs_dqflush_done(dqp);
+
 	/*
 	 * dqp is still locked, but caller is free to unlock it now.
 	 */
@@ -1483,7 +1435,7 @@ xfs_qm_dqpurge(
 	 */
 	if (XFS_DQ_IS_DIRTY(dqp)) {
 		int	error;
-		xfs_dqtrace_entry(dqp, "DQPURGE ->DQFLUSH: DQDIRTY");
+
 		/* dqflush unlocks dqflock */
 		/*
 		 * Given that dqpurge is a very rare occurrence, it is OK