[PATCH] um: add support for TIF_NOTIFY_SIGNAL

[Jens Axboe]

On 11/5/20 11:15 AM, Anton Ivanov wrote:
> 
> 
> On 29/10/2020 16:23, Jens Axboe wrote:
>> Wire up TIF_NOTIFY_SIGNAL handling for um.
>>
>> Cc: linux-um at lists.infradead.org
>> Signed-off-by: Jens Axboe <axboe at 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/um/include/asm/thread_info.h | 2 ++
>>   arch/um/kernel/process.c          | 3 ++-
>>   2 files changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/um/include/asm/thread_info.h b/arch/um/include/asm/thread_info.h
>> index 4c19ce4c49f1..3b1cb8b3b186 100644
>> --- a/arch/um/include/asm/thread_info.h
>> +++ b/arch/um/include/asm/thread_info.h
>> @@ -57,6 +57,7 @@ static inline struct thread_info *current_thread_info(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_RESTART_BLOCK	4
>>   #define TIF_MEMDIE		5	/* is terminating due to OOM killer */
>>   #define TIF_SYSCALL_AUDIT	6
>> @@ -67,6 +68,7 @@ static inline struct thread_info *current_thread_info(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_MEMDIE		(1 << TIF_MEMDIE)
>>   #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
>>   #define _TIF_SECCOMP		(1 << TIF_SECCOMP)
>> diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
>> index 3bed09538dd9..9e19da9e6198 100644
>> --- a/arch/um/kernel/process.c
>> +++ b/arch/um/kernel/process.c
>> @@ -99,7 +99,8 @@ void interrupt_end(void)
>>   
>>   	if (need_resched())
>>   		schedule();
>> -	if (test_thread_flag(TIF_SIGPENDING))
>> +	if (test_thread_flag(TIF_SIGPENDING) ||
>> +	    test_thread_flag(TIF_NOTIFY_SIGNAL))
>>   		do_signal(regs);
>>   	if (test_thread_flag(TIF_NOTIFY_RESUME))
>>   		tracehook_notify_resume(regs);
>>
> 
> Acked-By: Anton Ivanov <anton.ivanov at cambridgegreys.com>

Thanks, added.

-- 
Jens Axboe