hollalinux
/
linux-sg2042
mirror of https://github.com/sophgo/linux-riscv.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

tracing: Fix check for cpu online when event is disabled 

Commit f37755490f ("tracepoints: Do not trace when cpu is offline") added
a check to make sure that tracepoints only get called when the cpu is
online, as it uses rcu_read_lock_sched() for protection.

Commit 3a630178fd ("tracing: generate RCU warnings even when tracepoints
are disabled") added lockdep checks (including rcu checks) for events that
are not enabled to catch possible RCU issues that would only be triggered if
a trace event was enabled. Commit f37755490f only stopped the warnings
when the trace event was enabled but did not prevent warnings if the trace
event was called when disabled.

To fix this, the cpu online check is moved to where the condition is added
to the trace event. This will place the cpu online check in all places that
it may be used now and in the future.

Cc: stable@vger.kernel.org # v3.18+
Fixes: f37755490f ("tracepoints: Do not trace when cpu is offline")
Fixes: 3a630178fd ("tracing: generate RCU warnings even when tracepoints are disabled")
Reported-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (Red Hat) 2016-03-09 11:58:41 -05:00 committed by Steven Rostedt
parent f6cede5b49
commit dc17147de3
1 changed files with 9 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
include/linux/tracepoint.h
View File

@ -134,9 +134,6 @@ extern void syscall_unregfunc(void);
void *it_func; \
void *__data; \
\
if (!cpu_online(raw_smp_processor_id())) \
return; \
\
if (!(cond)) \
return; \
prercu; \
@ -343,15 +340,19 @@ extern void syscall_unregfunc(void);
* "void *__data, proto" as the callback prototype.
*/
#define DECLARE_TRACE_NOARGS(name) \
__DECLARE_TRACE(name, void, , 1, void *__data, __data)
__DECLARE_TRACE(name, void, , \
cpu_online(raw_smp_processor_id()), \
void *__data, __data)
#define DECLARE_TRACE(name, proto, args) \
__DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), 1, \
PARAMS(void *__data, proto), \
PARAMS(__data, args))
__DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), \
cpu_online(raw_smp_processor_id()), \
PARAMS(void *__data, proto), \
PARAMS(__data, args))
#define DECLARE_TRACE_CONDITION(name, proto, args, cond) \
__DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), PARAMS(cond), \
__DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), \
cpu_online(raw_smp_processor_id()) && (PARAMS(cond)), \
PARAMS(void *__data, proto), \
PARAMS(__data, args))