Re: [PATCH] sh: add support for TIF_NOTIFY_SIGNAL

From: Jens Axboe <axboe@kernel.dk>
To: linux-sh@vger.kernel.org
Subject: Re: [PATCH] sh: add support for TIF_NOTIFY_SIGNAL
Date: Thu, 05 Nov 2020 16:17:44 +0000	[thread overview]
Message-ID: <ae29ab73-ee7a-2bb7-3fd8-3037f40c1cbd@kernel.dk> (raw)
In-Reply-To: <5fcc82b4-89ae-3bca-10ab-6ad933565cee@kernel.dk>

Gentle nudge on this one.

On 10/29/20 10:21 AM, Jens Axboe wrote:
> Wire up TIF_NOTIFY_SIGNAL handling for sh.
> 
> Cc: linux-sh@vger.kernel.org
> Signed-off-by: Jens Axboe <axboe@kernel.dk>
> ---
> 
> 5.11 has support queued up for TIF_NOTIFY_SIGNAL, see this posting
> for details:
> 
> https://lore.kernel.org/io-uring/20201026203230.386348-1-axboe@kernel.dk/
> 
> As part of that work, I'm adding TIF_NOTIFY_SIGNAL support to all archs,
> as that will enable a set of cleanups once all of them support it. I'm
> happy carrying this patch if need be, or it can be funelled through the
> arch tree. Let me know.
> 
>  arch/sh/include/asm/thread_info.h | 4 +++-
>  arch/sh/kernel/signal_32.c        | 7 +++++--
>  2 files changed, 8 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/sh/include/asm/thread_info.h b/arch/sh/include/asm/thread_info.h
> index 243ea5150aa0..598d0184ffea 100644
> --- a/arch/sh/include/asm/thread_info.h
> +++ b/arch/sh/include/asm/thread_info.h
> @@ -105,6 +105,7 @@ extern void init_thread_xstate(void);
>  #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
>  #define TIF_SIGPENDING		1	/* signal pending */
>  #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
> +#define TIF_NOTIFY_SIGNAL	3	/* signal notifications exist */
>  #define TIF_SINGLESTEP		4	/* singlestepping active */
>  #define TIF_SYSCALL_AUDIT	5	/* syscall auditing active */
>  #define TIF_SECCOMP		6	/* secure computing */
> @@ -116,6 +117,7 @@ extern void init_thread_xstate(void);
>  #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
>  #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
>  #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
> +#define _TIF_NOTIFY_SIGNAL	(1 << TIF_NOTIFY_SIGNAL)
>  #define _TIF_SINGLESTEP		(1 << TIF_SINGLESTEP)
>  #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
>  #define _TIF_SECCOMP		(1 << TIF_SECCOMP)
> @@ -132,7 +134,7 @@ extern void init_thread_xstate(void);
>  #define _TIF_ALLWORK_MASK	(_TIF_SYSCALL_TRACE | _TIF_SIGPENDING      | \
>  				 _TIF_NEED_RESCHED  | _TIF_SYSCALL_AUDIT   | \
>  				 _TIF_SINGLESTEP    | _TIF_NOTIFY_RESUME   | \
> -				 _TIF_SYSCALL_TRACEPOINT)
> +				 _TIF_SYSCALL_TRACEPOINT | _TIF_NOTIFY_SIGNAL)
>  
>  /* work to do on interrupt/exception return */
>  #define _TIF_WORK_MASK		(_TIF_ALLWORK_MASK & ~(_TIF_SYSCALL_TRACE | \
> diff --git a/arch/sh/kernel/signal_32.c b/arch/sh/kernel/signal_32.c
> index 1add47fd31f6..8cfae5a75edb 100644
> --- a/arch/sh/kernel/signal_32.c
> +++ b/arch/sh/kernel/signal_32.c
> @@ -466,7 +466,10 @@ static void do_signal(struct pt_regs *regs, unsigned int save_r0)
>  	if (!user_mode(regs))
>  		return;
>  
> -	if (get_signal(&ksig)) {
> +	if (ti_work & _TIF_NOTIFY_SIGNAL)
> +		tracehook_notify_signal();
> +
> +	if ((ti_work & _TIF_SIGPENDING) && get_signal(&ksig)) {
>  		handle_syscall_restart(save_r0, regs, &ksig.ka.sa);
>  
>  		/* Whee!  Actually deliver the signal.  */
> @@ -499,7 +502,7 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, unsigned int save_r0,
>  				 unsigned long thread_info_flags)
>  {
>  	/* deal with pending signal delivery */
> -	if (thread_info_flags & _TIF_SIGPENDING)
> +	if (thread_info_flags & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL))
>  		do_signal(regs, save_r0);
>  
>  	if (thread_info_flags & _TIF_NOTIFY_RESUME)
> 

-- 
Jens Axboe