[PATCH 4.4 44/96] SUNRPC: Fix tracepoint storage issues with svc_recv and svc_rqst_status

Greg Kroah-Hartman
2017-11-28T10:30:00Z

From: Trond Myklebust <trond.myklebust@primarydata.com>

commit e9d4bf219c83d09579bc62512fea2ca10f025d93 upstream.

There is no guarantee that either the request or the svc_xprt exist
by the time we get round to printing the trace message.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
include/trace/events/sunrpc.h | 17 ++++++++++-------
1 file changed, 10 insertions(+), 7 deletions(-)

--- a/include/trace/events/sunrpc.h
+++ b/include/trace/events/sunrpc.h
@@ -455,20 +455,22 @@ TRACE_EVENT(svc_recv,
TP_ARGS(rqst, status),

TP_STRUCT__entry(
- __field(struct sockaddr *, addr)
__field(__be32, xid)
__field(int, status)
__field(unsigned long, flags)
+ __dynamic_array(unsigned char, addr, rqst->rq_addrlen)
),

TP_fast_assign(
- __entry->addr = (struct sockaddr *)&rqst->rq_addr;
__entry->xid = status > 0 ? rqst->rq_xid : 0;
__entry->status = status;
__entry->flags = rqst->rq_flags;
+ memcpy(__get_dynamic_array(addr),
+ &rqst->rq_addr, rqst->rq_addrlen);
),

- TP_printk("addr=%pIScp xid=0x%x status=%d flags=%s", __entry->addr,
+ TP_printk("addr=%pIScp xid=0x%x status=%d flags=%s",
+ (struct sockaddr *)__get_dynamic_array(addr),
be32_to_cpu(__entry->xid), __entry->status,
show_rqstp_flags(__entry->flags))
);
@@ -480,22 +482,23 @@ DECLARE_EVENT_CLASS(svc_rqst_status,
TP_ARGS(rqst, status),

TP_STRUCT__entry(
- __field(struct sockaddr *, addr)
__field(__be32, xid)
- __field(int, dropme)
__field(int, status)
__field(unsigned long, flags)
+ __dynamic_array(unsigned char, addr, rqst->rq_addrlen)
),

TP_fast_assign(
- __entry->addr = (struct sockaddr *)&rqst->rq_addr;
__entry->xid = rqst->rq_xid;
__entry->status = status;
__entry->flags = rqst->rq_flags;
+ memcpy(__get_dynamic_array(addr),
+ &rqst->rq_addr, rqst->rq_addrlen);
),

TP_printk("addr=%pIScp rq_xid=0x%x status=%d flags=%s",
- __entry->addr, be32_to_cpu(__entry->xid),
+ (struct sockaddr *)__get_dynamic_array(addr),
+ be32_to_cpu(__entry->xid),
__entry->status, show_rqstp_flags(__entry->flags))
);