powerpc/pseries: Don't trace hcalls on offline CPUs

If a cpu is hotplugged while the hcall trace points are active, it's
possible to hit a warning from RCU due to the trace points calling into
RCU from an offline cpu, eg:

  RCU used illegally from offline CPU!
  rcu_scheduler_active = 1, debug_locks = 1

Make the hypervisor tracepoints conditional by using
TRACE_EVENT_FN_COND.

Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Denis Kirjanov <kda@linux-powerpc.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Denis Kirjanov 2015-12-14 23:18:06 +03:00 committed by Michael Ellerman
parent f15838e9ca
commit 126df08c52

View File

@ -57,12 +57,14 @@ DEFINE_EVENT(ppc64_interrupt_class, timer_interrupt_exit,
extern void hcall_tracepoint_regfunc(void);
extern void hcall_tracepoint_unregfunc(void);
TRACE_EVENT_FN(hcall_entry,
TRACE_EVENT_FN_COND(hcall_entry,
TP_PROTO(unsigned long opcode, unsigned long *args),
TP_ARGS(opcode, args),
TP_CONDITION(cpu_online(raw_smp_processor_id())),
TP_STRUCT__entry(
__field(unsigned long, opcode)
),
@ -76,13 +78,15 @@ TRACE_EVENT_FN(hcall_entry,
hcall_tracepoint_regfunc, hcall_tracepoint_unregfunc
);
TRACE_EVENT_FN(hcall_exit,
TRACE_EVENT_FN_COND(hcall_exit,
TP_PROTO(unsigned long opcode, unsigned long retval,
unsigned long *retbuf),
TP_ARGS(opcode, retval, retbuf),
TP_CONDITION(cpu_online(raw_smp_processor_id())),
TP_STRUCT__entry(
__field(unsigned long, opcode)
__field(unsigned long, retval)