Subject: Re: linux-next: Tree for Nov 2

From: Stephen Rothwell <[email-masked]>
Date: Mon, 2 Nov 2015 17:30:23 +1100

Hi Sergey,

[Excess quoted for new cc's]

On Mon, 2 Nov 2015 14:58:16 +0900 Sergey Senozhatsky <[email-masked]> wrote:
>
> unregister_trace_sched_switch/register_trace_prio_sched_switch/etc.
> (see the log below. 80-cols unfriendly. sorry.)
> expect proto to contain 'bool preempt'
> 
> TRACE_EVENT(sched_switch,
> 
>         TP_PROTO(bool preempt,
>                  struct task_struct *prev,
>                  struct task_struct *next),
> 
> 
> event_filter_pid_sched_switch_probe_post() and
> event_filter_pid_sched_switch_probe_pre() are missing it.
> which results in:
> 
> kernel/trace/trace_events.c: In function ‘__ftrace_clear_event_pids’:
> kernel/trace/trace_events.c:579:32: warning: passing argument 1 of ‘unregister_trace_sched_switch’ from incompatible pointer type [-Wincompatible-pointer-types]
>   unregister_trace_sched_switch(event_filter_pid_sched_switch_probe_pre, tr);
>                                 ^
> In file included from include/trace/events/sched.h:8:0,
>                  from kernel/trace/trace_events.c:25:
> include/linux/tracepoint.h:223:2: note: expected ‘void (*)(void *, bool,  struct task_struct *, struct task_struct *) {aka void (*)(void *, _Bool,  struct task_struct *, struct task_struct *)}’ but argument is of type ‘void (*)(void *, struct task_struct *, struct task_struct *)’
>   unregister_trace_##name(void (*probe)(data_proto), void *data) \
>   ^
> include/linux/tracepoint.h:357:3: note: in expansion of macro ‘__DECLARE_TRACE’
>    __DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), 1, \
>    ^
> include/linux/tracepoint.h:491:2: note: in expansion of macro ‘DECLARE_TRACE’
>   DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))
>   ^
> include/trace/events/sched.h:124:1: note: in expansion of macro ‘TRACE_EVENT’
>  TRACE_EVENT(sched_switch,
>  ^
> kernel/trace/trace_events.c:580:32: warning: passing argument 1 of ‘unregister_trace_sched_switch’ from incompatible pointer type [-Wincompatible-pointer-types]
>   unregister_trace_sched_switch(event_filter_pid_sched_switch_probe_post, tr);
>                                 ^
> In file included from include/trace/events/sched.h:8:0,
>                  from kernel/trace/trace_events.c:25:
> include/linux/tracepoint.h:223:2: note: expected ‘void (*)(void *, bool,  struct task_struct *, struct task_struct *) {aka void (*)(void *, _Bool,  struct task_struct *, struct task_struct *)}’ but argument is of type ‘void (*)(void *, struct task_struct *, struct task_struct *)’
>   unregister_trace_##name(void (*probe)(data_proto), void *data) \
>   ^
> include/linux/tracepoint.h:357:3: note: in expansion of macro ‘__DECLARE_TRACE’
>    __DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), 1, \
>    ^
> include/linux/tracepoint.h:491:2: note: in expansion of macro ‘DECLARE_TRACE’
>   DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))
>   ^
> include/trace/events/sched.h:124:1: note: in expansion of macro ‘TRACE_EVENT’
>  TRACE_EVENT(sched_switch,
>  ^
> kernel/trace/trace_events.c: In function ‘ftrace_event_pid_write’:
> kernel/trace/trace_events.c:1723:36: warning: passing argument 1 of ‘register_trace_prio_sched_switch’ from incompatible pointer type [-Wincompatible-pointer-types]
>    register_trace_prio_sched_switch(event_filter_pid_sched_switch_probe_pre,
>                                     ^
> In file included from include/trace/events/sched.h:8:0,
>                  from kernel/trace/trace_events.c:25:
> include/linux/tracepoint.h:216:2: note: expected ‘void (*)(void *, bool,  struct task_struct *, struct task_struct *) {aka void (*)(void *, _Bool,  struct task_struct *, struct task_struct *)}’ but argument is of type ‘void (*)(void *, struct task_struct *, struct task_struct *)’
>   register_trace_prio_##name(void (*probe)(data_proto), void *data,\
>   ^
> include/linux/tracepoint.h:357:3: note: in expansion of macro ‘__DECLARE_TRACE’
>    __DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), 1, \
>    ^
> include/linux/tracepoint.h:491:2: note: in expansion of macro ‘DECLARE_TRACE’
>   DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))
>   ^
> include/trace/events/sched.h:124:1: note: in expansion of macro ‘TRACE_EVENT’
>  TRACE_EVENT(sched_switch,
>  ^
> kernel/trace/trace_events.c:1725:36: warning: passing argument 1 of ‘register_trace_prio_sched_switch’ from incompatible pointer type [-Wincompatible-pointer-types]
>    register_trace_prio_sched_switch(event_filter_pid_sched_switch_probe_post,
>                                     ^
> In file included from include/trace/events/sched.h:8:0,
>                  from kernel/trace/trace_events.c:25:
> include/linux/tracepoint.h:216:2: note: expected ‘void (*)(void *, bool,  struct task_struct *, struct task_struct *) {aka void (*)(void *, _Bool,  struct task_struct *, struct task_struct *)}’ but argument is of type ‘void (*)(void *, struct task_struct *, struct task_struct *)’
>   register_trace_prio_##name(void (*probe)(data_proto), void *data,\
>   ^
> include/linux/tracepoint.h:357:3: note: in expansion of macro ‘__DECLARE_TRACE’
>    __DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), 1, \
>    ^
> include/linux/tracepoint.h:491:2: note: in expansion of macro ‘DECLARE_TRACE’
>   DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))
>   ^
> include/trace/events/sched.h:124:1: note: in expansion of macro ‘TRACE_EVENT’
>  TRACE_EVENT(sched_switch,

Presumably caused by the interaction of commit

  3fdaf80f4a83 ("tracing: Implement event pid filtering")

from the trace tree and commit

  c73464b1c843 ("sched/core: Fix trace_sched_switch()")

from the tip tree.

> something like this, I guess.
> 
> ===8<===8<===8<===8<===
> 
> Add missing 'bool preempt' argument as required by
> sched_switch's trace event proto:
> 
> : TRACE_EVENT(sched_switch,
> :
> :         TP_PROTO(bool preempt,
> :                  struct task_struct *prev,
> :                  struct task_struct *next),
> ...
> 
> to event_filter_pid_sched_switch_probe_post() and
> event_filter_pid_sched_switch_probe_pre() functions.
> 
> kernel/trace/trace_events.c: In function ‘__ftrace_clear_event_pids’:
> kernel/trace/trace_events.c:579:32: warning: passing argument 1 of
>   ‘unregister_trace_sched_switch’ from incompatible pointer type
>   [-Wincompatible-pointer-types]
>   unregister_trace_sched_switch(event_filter_pid_sched_switch_probe_pre, tr);
>                                 ^
> In file included from include/trace/events/sched.h:8:0,
>                  from kernel/trace/trace_events.c:25:
> include/linux/tracepoint.h:223:2: note: expected
>   ‘void (*)(void *, bool,  struct task_struct *, struct task_struct *)
> {aka void (*)(void *, _Bool,  struct task_struct *, struct task_struct *)}’
> but argument is of type
>   ‘void (*)(void *, struct task_struct *, struct task_struct *)’
>   unregister_trace_##name(void (*probe)(data_proto), void *data) \
>   ^
> include/linux/tracepoint.h:357:3: note: in expansion of macro ‘__DECLARE_TRACE’
>    __DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), 1, \
>    ^
> include/linux/tracepoint.h:491:2: note: in expansion of macro ‘DECLARE_TRACE’
>   DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))
>   ^
> include/trace/events/sched.h:124:1: note: in expansion of macro ‘TRACE_EVENT’
>  TRACE_EVENT(sched_switch,
>  ^
> 
> Signed-off-by: Sergey Senozhatsky <[email-masked]>
> ---
>  kernel/trace/trace_events.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
> index fb0261e..0d86f0c 100644
> --- a/kernel/trace/trace_events.c
> +++ b/kernel/trace/trace_events.c
> @@ -506,7 +506,7 @@ check_ignore_pid(struct trace_pid_list *filtered_pids, struct task_struct *task)
>  }
>  
>  static void
> -event_filter_pid_sched_switch_probe_pre(void *data,
> +event_filter_pid_sched_switch_probe_pre(void *data, bool preempt,
>  		    struct task_struct *prev, struct task_struct *next)
>  {
>  	struct trace_array *tr = data;
> @@ -520,7 +520,7 @@ event_filter_pid_sched_switch_probe_pre(void *data,
>  }
>  
>  static void
> -event_filter_pid_sched_switch_probe_post(void *data,
> +event_filter_pid_sched_switch_probe_post(void *data, bool preempt,
>  		    struct task_struct *prev, struct task_struct *next)
>  {
>  	struct trace_array *tr = data;
> -- 
> 2.6.2.402.g2635c2b

So I guess I need that (or something similar) in linux-next until these
trees are merged.

-- 
Cheers,
Stephen Rothwell                    [email-masked]