[PATCH 12/18] nfsd: add trace events

Christoph Hellwig
2015-01-06T16:29:49Z

For now just a few simple events to trace the layout stateid lifetime, but
these already were enough to find several bugs in the Linux client layout
stateid handling.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/nfsd/Makefile | 7 ++++++-
fs/nfsd/nfs4layouts.c | 16 ++++++++++++++-
fs/nfsd/nfs4proc.c | 6 +++++-
fs/nfsd/trace.c | 5 +++++
fs/nfsd/trace.h | 54 +++++++++++++++++++++++++++++++++++++++++++++++++++
5 files changed, 85 insertions(+), 3 deletions(-)
create mode 100644 fs/nfsd/trace.c
create mode 100644 fs/nfsd/trace.h

diff --git a/fs/nfsd/Makefile b/fs/nfsd/Makefile
index 5806270..6cba933 100644
--- a/fs/nfsd/Makefile
+++ b/fs/nfsd/Makefile
@@ -2,9 +2,14 @@
# Makefile for the Linux nfs server
#

+ccflags-y += -I$(src) # needed for trace events
+
obj-$(CONFIG_NFSD) += nfsd.o

-nfsd-y := nfssvc.o nfsctl.o nfsproc.o nfsfh.o vfs.o \
+# this one should be compiled first, as the tracing macros can easily blow up
+nfsd-y += trace.o
+
+nfsd-y += nfssvc.o nfsctl.o nfsproc.o nfsfh.o vfs.o \
export.o auth.o lockd.o nfscache.o nfsxdr.o stats.o
nfsd-$(CONFIG_NFSD_FAULT_INJECTION) += fault_inject.o
nfsd-$(CONFIG_NFSD_V2_ACL) += nfs2acl.o
diff --git a/fs/nfsd/nfs4layouts.c b/fs/nfsd/nfs4layouts.c
index 72a12ca..bb91981 100644
--- a/fs/nfsd/nfs4layouts.c
+++ b/fs/nfsd/nfs4layouts.c
@@ -9,6 +9,7 @@

#include "pnfs.h"
#include "netns.h"
+#include "trace.h"

#define NFSDDBG_FACILITY NFSDDBG_PNFS

@@ -124,6 +125,8 @@ nfsd4_free_layout_stateid(struct nfs4_stid *stid)
struct nfs4_client *clp = ls->ls_stid.sc_client;
struct nfs4_file *fp = ls->ls_stid.sc_file;

+ trace_layoutstate_free(&ls->ls_stid.sc_stateid);
+
spin_lock(&clp->cl_lock);
list_del_init(&ls->ls_perclnt);
spin_unlock(&clp->cl_lock);
@@ -214,6 +217,7 @@ nfsd4_alloc_layout_stateid(struct nfsd4_compound_state *cstate,
list_add(&ls->ls_perfile, &fp->fi_lo_states);
spin_unlock(&fp->fi_lock);

+ trace_layoutstate_alloc(&ls->ls_stid.sc_stateid);
return ls;
}

@@ -279,6 +283,8 @@ nfsd4_recall_file_layout(struct nfs4_layout_stateid *ls)
if (list_empty(&ls->ls_layouts))
goto out_unlock;

+ trace_layout_recall(&ls->ls_stid.sc_stateid);
+
atomic_inc(&ls->ls_stid.sc_count);
update_stateid(&ls->ls_stid.sc_stateid);
memcpy(&ls->ls_recall_sid, &ls->ls_stid.sc_stateid, sizeof(stateid_t));
@@ -453,8 +459,10 @@ nfsd4_return_file_layouts(struct svc_rqst *rqstp,
nfserr = nfsd4_preprocess_layout_stateid(rqstp, cstate, &lrp->lr_sid,
false, lrp->lr_layout_type,
&ls);
- if (nfserr)
+ if (nfserr) {
+ trace_layout_return_lookup_fail(&lrp->lr_sid);
return nfserr;
+ }

spin_lock(&ls->ls_lock);
list_for_each_entry_safe(lp, n, &ls->ls_layouts, lo_perstate) {
@@ -471,6 +479,7 @@ nfsd4_return_file_layouts(struct svc_rqst *rqstp,
}
lrp->lrs_present = 1;
} else {
+ trace_layoutstate_unhash(&ls->ls_stid.sc_stateid);
nfs4_unhash_stid(&ls->ls_stid);
lrp->lrs_present = 0;
}
@@ -569,6 +578,8 @@ nfsd4_cb_layout_fail(struct nfs4_layout_stateid *ls)

rpc_ntop((struct sockaddr *)&clp->cl_addr, addr_str, sizeof(addr_str));

+ nfsd4_cb_layout_fail(ls);
+
printk(KERN_WARNING
"nfsd: client %s failed to respond to layout recall. "
" Fencing..\n", addr_str);
@@ -596,6 +607,7 @@ nfsd4_cb_layout_done(struct nfsd4_callback *cb, struct rpc_task *task)
case 0:
return 1;
case -NFS4ERR_NOMATCHING_LAYOUT:
+ trace_layout_recall_done(&ls->ls_stid.sc_stateid);
task->tk_status = 0;
return 1;
case -NFS4ERR_DELAY:
@@ -623,6 +635,8 @@ nfsd4_cb_layout_release(struct nfsd4_callback *cb)
container_of(cb, struct nfs4_layout_stateid, ls_recall);
LIST_HEAD(reaplist);

+ trace_layout_recall_release(&ls->ls_stid.sc_stateid);
+
nfsd4_return_all_layouts(ls, &reaplist);
nfsd4_free_layouts(&reaplist);
nfs4_put_stid(&ls->ls_stid);
diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index c051d5b..28e3927 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -44,6 +44,7 @@
#include "netns.h"
#include "acl.h"
#include "pnfs.h"
+#include "trace.h"

#ifdef CONFIG_NFSD_V4_SECURITY_LABEL
#include <linux/security.h>
@@ -1298,8 +1299,10 @@ nfsd4_layoutget(struct svc_rqst *rqstp,

nfserr = nfsd4_preprocess_layout_stateid(rqstp, cstate, &lgp->lg_sid,
true, lgp->lg_layout_type, &ls);
- if (nfserr)
+ if (nfserr) {
+ trace_layout_get_lookup_fail(&lgp->lg_sid);
goto out;
+ }

nfserr = nfserr_recallconflict;
if (atomic_read(&ls->ls_stid.sc_file->fi_lo_recalls))
@@ -1359,6 +1362,7 @@ nfsd4_layoutcommit(struct svc_rqst *rqstp,
false, lcp->lc_layout_type,
&ls);
if (nfserr) {
+ trace_layout_commit_lookup_fail(&lcp->lc_sid);
/* fixup error code as per RFC5661 */
if (nfserr == nfserr_bad_stateid)
nfserr = nfserr_badlayout;
diff --git a/fs/nfsd/trace.c b/fs/nfsd/trace.c
new file mode 100644
index 0000000..82f8907
--- /dev/null
+++ b/fs/nfsd/trace.c
@@ -0,0 +1,5 @@
+
+#include "state.h"
+
+#define CREATE_TRACE_POINTS
+#include "trace.h"
diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h
new file mode 100644
index 0000000..c668520
--- /dev/null
+++ b/fs/nfsd/trace.h
@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 2014 Christoph Hellwig.
+ */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM nfsd
+
+#if !defined(_NFSD_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _NFSD_TRACE_H
+
+#include <linux/tracepoint.h>
+
+DECLARE_EVENT_CLASS(nfsd_stateid_class,
+ TP_PROTO(stateid_t *stp),
+ TP_ARGS(stp),
+ TP_STRUCT__entry(
+ __field(u32, cl_boot)
+ __field(u32, cl_id)
+ __field(u32, si_id)
+ __field(u32, si_generation)
+ ),
+ TP_fast_assign(
+ __entry->cl_boot = stp->si_opaque.so_clid.cl_boot;
+ __entry->cl_id = stp->si_opaque.so_clid.cl_id;
+ __entry->si_id = stp->si_opaque.so_id;
+ __entry->si_generation = stp->si_generation;
+ ),
+ TP_printk("client %08x:%08x stateid %08x:%08x",
+ __entry->cl_boot,
+ __entry->cl_id,
+ __entry->si_id,
+ __entry->si_generation)
+)
+
+#define DEFINE_STATEID_EVENT(name) \
+DEFINE_EVENT(nfsd_stateid_class, name, \
+ TP_PROTO(stateid_t *stp), \
+ TP_ARGS(stp))
+DEFINE_STATEID_EVENT(layoutstate_alloc);
+DEFINE_STATEID_EVENT(layoutstate_unhash);
+DEFINE_STATEID_EVENT(layoutstate_free);
+DEFINE_STATEID_EVENT(layout_get_lookup_fail);
+DEFINE_STATEID_EVENT(layout_commit_lookup_fail);
+DEFINE_STATEID_EVENT(layout_return_lookup_fail);
+DEFINE_STATEID_EVENT(layout_recall);
+DEFINE_STATEID_EVENT(layout_recall_done);
+DEFINE_STATEID_EVENT(layout_recall_fail);
+DEFINE_STATEID_EVENT(layout_recall_release);
+
+#endif /* _NFSD_TRACE_H */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#define TRACE_INCLUDE_FILE trace
+#include <trace/define_trace.h>
--
1.9.1