sh: add support for TIF_NOTIFY_SIGNAL

Wire up TIF_NOTIFY_SIGNAL handling for sh.

Cc [email protected]

Signed-off-by Jens Axboe <[email protected]>

---

5.11 has support queued up for TIF_NOTIFY_SIGNAL, see this posting for details:

https://lore.kernel.org/io-uring/[email protected]/

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(-)

arch/sh/include/asm/thread_info.h +3 -1

index 243ea5150aa0..598d0184ffea 100644
@@ -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 | \

arch/sh/kernel/signal_32.c +5 -2

index 1add47fd31f6..8cfae5a75edb 100644
@@ -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)

Gentle nudge on this one.

Hi Jens!

Quoted 1 line · Jens Axboe

Gentle nudge on this one.

I can build- and boot-test on SH and IA64.

I assume Rich will be fine with the SH changes, not sure about the IA64 and Tony.

Quoted 5 lines · John Paul Adrian Glaubitz

Hi Jens!

Quoted 1 line · Jens Axboe

Gentle nudge on this one.

Quoted 1 line

I can build- and boot-test on SH and IA64.

That'd be great, thanks!

Quoted 1 line

I assume Rich will be fine with the SH changes, not sure about the IA64 and Tony.

Let's add Tony - maybe he'll have a chance to take a look at the ia64 change.

Quoted 6 lines · John Paul Adrian Glaubitz

Hi Jens!

Quoted 1 line · Jens Axboe

Gentle nudge on this one.

I can build- and boot-test on SH and IA64.

That'd be great, thanks!

Quoted 6 lines · Jens Axboe

Quoted 5 lines · John Paul Adrian Glaubitz

Hi Jens!

Quoted 1 line · Jens Axboe

Gentle nudge on this one.

Quoted 7 lines

Quoted 1 line

I can build- and boot-test on SH and IA64.

That'd be great, thanks!

Quoted 1 line

I assume Rich will be fine with the SH changes, not sure about the IA64 and Tony.

Let's add Tony - maybe he'll have a chance to take a look at the ia64 change.

It breaks my ARCH=sh j2_defconfig build:

arch/sh/kernel/signal_32.c: In function 'do_signal':
arch/sh/kernel/signal_32.c:469:6: error: 'ti_work' undeclared (first use in this function)

Admittedly I'm testing a stack of 6 other patches at the same time:

[PATCH -next v2] sh: intc: Convert to DEFINE_SHOW_ATTRIBUTE.eml [PATCH] sh: dma: fix kconfig dependency for G2_DMA.eml
[PATCH] sh: remove CONFIG_IDE from most defconfig.eml
[PATCH] sh: Remove unused HAVE_COPY_THREAD_TLS macro.eml
[PATCH v1] sh: Drop ARCH_NR_GPIOS definition.eml
[PATCH v2 RESEND +TRIVIAL] arch_sh: hyphenate Non-Uniform in Kconfig prompt.eml

But this is the one I need to revert to get 5.10-rc3 to build, the rest compile.

Hi Jens!

Quoted 6 lines · Jens Axboe

Quoted 5 lines · John Paul Adrian Glaubitz

Hi Jens!

Quoted 1 line · Jens Axboe

Gentle nudge on this one.

Quoted 3 lines

Quoted 1 line

I can build- and boot-test on SH and IA64.

That'd be great, thanks!

Sorry for the delay. I'm busy at the moment and my SH board is currently building the Perl 5.32 package for Debian. Will try to test your patches by tomorrow, also ia64.

Quoted 33 lines · Jens Axboe

Quoted 31 lines · Rob Landley

Quoted 6 lines · Jens Axboe

Quoted 5 lines · John Paul Adrian Glaubitz

Hi Jens!

Quoted 1 line · Jens Axboe

Gentle nudge on this one.

Quoted 7 lines

Quoted 1 line

I can build- and boot-test on SH and IA64.

That'd be great, thanks!

Quoted 1 line

I assume Rich will be fine with the SH changes, not sure about the IA64 and Tony.

Let's add Tony - maybe he'll have a chance to take a look at the ia64 change.

It breaks my ARCH=sh j2_defconfig build:

arch/sh/kernel/signal_32.c: In function 'do_signal':
arch/sh/kernel/signal_32.c:469:6: error: 'ti_work' undeclared (first use in this function)

Admittedly I'm testing a stack of 6 other patches at the same time:

[PATCH -next v2] sh: intc: Convert to DEFINE_SHOW_ATTRIBUTE.eml [PATCH] sh: dma: fix kconfig dependency for G2_DMA.eml
[PATCH] sh: remove CONFIG_IDE from most defconfig.eml
[PATCH] sh: Remove unused HAVE_COPY_THREAD_TLS macro.eml
[PATCH v1] sh: Drop ARCH_NR_GPIOS definition.eml
[PATCH v2 RESEND +TRIVIAL] arch_sh: hyphenate Non-Uniform in Kconfig prompt.eml

But this is the one I need to revert to get 5.10-rc3 to build, the rest compile.

Quoted 1 line

Yeah that's my fault, this one should be a lot better...

arch/sh/kernel/signal_32.c: In function 'do_signal':
arch/sh/kernel/signal_32.c:471:3: error: implicit declaration of function 'tracehook_notify_signal'; did you mean 'tracehook_notify_resume'? [-Werror=implicit-function-declaration]

Keep 'em coming...

Quoted 30 lines · Rob Landley

Quoted 6 lines · Jens Axboe

Quoted 5 lines · John Paul Adrian Glaubitz

Hi Jens!

Quoted 1 line · Jens Axboe

Gentle nudge on this one.

Quoted 7 lines

Quoted 1 line

I can build- and boot-test on SH and IA64.

That'd be great, thanks!

Quoted 1 line

I assume Rich will be fine with the SH changes, not sure about the IA64 and Tony.

Let's add Tony - maybe he'll have a chance to take a look at the ia64 change.

It breaks my ARCH=sh j2_defconfig build:

arch/sh/kernel/signal_32.c: In function 'do_signal':
arch/sh/kernel/signal_32.c:469:6: error: 'ti_work' undeclared (first use in this function)

Admittedly I'm testing a stack of 6 other patches at the same time:

[PATCH -next v2] sh: intc: Convert to DEFINE_SHOW_ATTRIBUTE.eml [PATCH] sh: dma: fix kconfig dependency for G2_DMA.eml
[PATCH] sh: remove CONFIG_IDE from most defconfig.eml
[PATCH] sh: Remove unused HAVE_COPY_THREAD_TLS macro.eml
[PATCH v1] sh: Drop ARCH_NR_GPIOS definition.eml
[PATCH v2 RESEND +TRIVIAL] arch_sh: hyphenate Non-Uniform in Kconfig prompt.eml

Quoted 1 line

But this is the one I need to revert to get 5.10-rc3 to build, the rest compile.

Yeah that's my fault, this one should be a lot better...

Quoted 44 lines · Jens Axboe

Quoted 43 lines · Rob Landley

Quoted 31 lines · Jens Axboe

Quoted 30 lines · Rob Landley

Quoted 6 lines · Jens Axboe

Quoted 5 lines · John Paul Adrian Glaubitz

Hi Jens!

Quoted 1 line · Jens Axboe

Gentle nudge on this one.

Quoted 7 lines

Quoted 1 line

I can build- and boot-test on SH and IA64.

That'd be great, thanks!

Quoted 1 line

I assume Rich will be fine with the SH changes, not sure about the IA64 and Tony.

Let's add Tony - maybe he'll have a chance to take a look at the ia64 change.

It breaks my ARCH=sh j2_defconfig build:

arch/sh/kernel/signal_32.c: In function 'do_signal':
arch/sh/kernel/signal_32.c:469:6: error: 'ti_work' undeclared (first use in this function)

Admittedly I'm testing a stack of 6 other patches at the same time:

[PATCH -next v2] sh: intc: Convert to DEFINE_SHOW_ATTRIBUTE.eml [PATCH] sh: dma: fix kconfig dependency for G2_DMA.eml
[PATCH] sh: remove CONFIG_IDE from most defconfig.eml
[PATCH] sh: Remove unused HAVE_COPY_THREAD_TLS macro.eml
[PATCH v1] sh: Drop ARCH_NR_GPIOS definition.eml
[PATCH v2 RESEND +TRIVIAL] arch_sh: hyphenate Non-Uniform in Kconfig prompt.eml

Quoted 3 lines

Quoted 1 line

But this is the one I need to revert to get 5.10-rc3 to build, the rest compile.

Yeah that's my fault, this one should be a lot better...

arch/sh/kernel/signal_32.c: In function 'do_signal':
arch/sh/kernel/signal_32.c:471:3: error: implicit declaration of function 'tracehook_notify_signal'; did you mean 'tracehook_notify_resume'? [-Werror=implicit-function-declaration]

Quoted 4 lines

Quoted 1 line

Keep 'em coming...

Gah, it was still using the old style. This one should work and be correct, promise, double checked :-)

This one compiled fine. What does it do? (I ask having read
https://lwn.net/Articles/835340/ and come out none the wiser.)

I can try it on hardware in the morning, it's 1am in this time zone...

Quoted 43 lines · Rob Landley

Quoted 31 lines · Jens Axboe

Quoted 30 lines · Rob Landley

Quoted 6 lines · Jens Axboe

Quoted 5 lines · John Paul Adrian Glaubitz

Hi Jens!

Quoted 1 line · Jens Axboe

Gentle nudge on this one.

Quoted 7 lines

Quoted 1 line

I can build- and boot-test on SH and IA64.

That'd be great, thanks!

Quoted 1 line

I assume Rich will be fine with the SH changes, not sure about the IA64 and Tony.

Let's add Tony - maybe he'll have a chance to take a look at the ia64 change.

It breaks my ARCH=sh j2_defconfig build:

arch/sh/kernel/signal_32.c: In function 'do_signal':
arch/sh/kernel/signal_32.c:469:6: error: 'ti_work' undeclared (first use in this function)

Admittedly I'm testing a stack of 6 other patches at the same time:

[PATCH -next v2] sh: intc: Convert to DEFINE_SHOW_ATTRIBUTE.eml [PATCH] sh: dma: fix kconfig dependency for G2_DMA.eml
[PATCH] sh: remove CONFIG_IDE from most defconfig.eml
[PATCH] sh: Remove unused HAVE_COPY_THREAD_TLS macro.eml
[PATCH v1] sh: Drop ARCH_NR_GPIOS definition.eml
[PATCH v2 RESEND +TRIVIAL] arch_sh: hyphenate Non-Uniform in Kconfig prompt.eml

Quoted 3 lines

Quoted 1 line

But this is the one I need to revert to get 5.10-rc3 to build, the rest compile.

Yeah that's my fault, this one should be a lot better...

arch/sh/kernel/signal_32.c: In function 'do_signal':
arch/sh/kernel/signal_32.c:471:3: error: implicit declaration of function 'tracehook_notify_signal'; did you mean 'tracehook_notify_resume'? [-Werror=implicit-function-declaration]

Quoted 1 line

Keep 'em coming...

Gah, it was still using the old style. This one should work and be correct, promise, double checked :-)

Quoted 3 lines

Sorry for the delay. I'm busy at the moment and my SH board is currently building the Perl 5.32 package for Debian. Will try to test your patches by tomorrow, also ia64.

Thanks, both would be appreciated! Just CC'ed you on the updated patch for sh.

Hi Jens!

Quoted 4 lines · Jens Axboe

Quoted 3 lines

Sorry for the delay. I'm busy at the moment and my SH board is currently building the Perl 5.32 package for Debian. Will try to test your patches by tomorrow, also ia64.

Quoted 2 lines

Thanks, both would be appreciated! Just CC'ed you on the updated patch for sh.

Is this still relevant for testing? I'm ready to test now, much later than I thought, sorry.

I'm going to build Linus' latest kernel for my SH and IA64 machines now and then I can test additional patches on top of it.

Quoted 13 lines · John Paul Adrian Glaubitz

Hi Jens!

Quoted 6 lines · Jens Axboe

Quoted 3 lines

Sorry for the delay. I'm busy at the moment and my SH board is currently building the Perl 5.32 package for Debian. Will try to test your patches by tomorrow, also ia64.

Thanks, both would be appreciated! Just CC'ed you on the updated patch for sh.

Is this still relevant for testing? I'm ready to test now, much later than I thought, sorry.

Quoted 2 lines

I'm going to build Linus' latest kernel for my SH and IA64 machines now and then I can test additional patches on top of it.

Thanks, would definitely still appreciate testing. You can just run linux-next if you want, it's got everything in there. Or apply the separate patches to -git, either approach is fine.

Hi Jens!

Quoted 14 lines · Jens Axboe

Quoted 13 lines · John Paul Adrian Glaubitz

Hi Jens!

Quoted 6 lines · Jens Axboe

Quoted 3 lines

Sorry for the delay. I'm busy at the moment and my SH board is currently building the Perl 5.32 package for Debian. Will try to test your patches by tomorrow, also ia64.

Thanks, both would be appreciated! Just CC'ed you on the updated patch for sh.

Is this still relevant for testing? I'm ready to test now, much later than I thought, sorry.

Quoted 6 lines

Quoted 2 lines

I'm going to build Linus' latest kernel for my SH and IA64 machines now and then I can test additional patches on top of it.

Thanks, would definitely still appreciate testing. You can just run linux-next if you want, it's got everything in there. Or apply the separate patches to -git, either approach is fine.

Apologies for the late reply.

I just pulled Linus' latest tree today with your patch for SH included and I'm not seeing any regressions.

Is there away to test the change itself?

Quoted 1 line · John Paul Adrian Glaubitz

Is there away to test the change itself?

The only user of TWA_SIGNAL, which uses TIF_NOTIFY_SIGNAL, so far is io_uring. You need something that triggers deferred task_work processing, which is basically anything that ends up being poll driven for data/space readiness. Here's a small test app from the liburing test suite, that'll trigger it.

If you install liburing, compile with:

gcc -Wall -O2 -o socket-rw socket-rw.c -luring

and run it without any arguments.

Hi Jens!

Quoted 8 lines · Jens Axboe

Quoted 1 line · John Paul Adrian Glaubitz

Is there away to test the change itself?

The only user of TWA_SIGNAL, which uses TIF_NOTIFY_SIGNAL, so far is io_uring. You need something that triggers deferred task_work processing, which is basically anything that ends up being poll driven for data/space readiness. Here's a small test app from the liburing test suite, that'll trigger it.

Quoted 5 lines

If you install liburing, compile with:

gcc -Wall -O2 -o socket-rw socket-rw.c -luring

and run it without any arguments.

How long is this test supposed to run? It's already been running for some minutes on my 600 MHz machine.

axboe@p1 ~> time ./socket-rw 0.000s

________________________________________________________
Executed in 1.10 millis fish external
usr time 888.00 micros 278.00 micros 610.00 micros
sys time 35.00 micros 35.00 micros 0.00 micros

If it doesn't, can you try:

# echo 1 > /sys/kernel/debug/tracing/events/io_uring/enable

Then run the socket-rw app, and then do:

# cat /sys/kernel/debug/tracing/trace

and send that output? Might also be useful to include the strace of the socket-rw just in case, so maybe run it ala

strace -o foo ./socket-rw

and include foo in the reply as well.

On 1/1/21 4:35 PM, Jens Axboe wrote:> It's supposed to finish very quickly:

Quoted 16 lines

axboe@p1 ~> time ./socket-rw 0.000s

________________________________________________________
Executed in 1.10 millis fish external
usr time 888.00 micros 278.00 micros 610.00 micros
sys time 35.00 micros 35.00 micros 0.00 micros

If it doesn't, can you try:

# echo 1 > /sys/kernel/debug/tracing/events/io_uring/enable

Then run the socket-rw app, and then do:

# cat /sys/kernel/debug/tracing/trace

Quoted 6 lines

and send that output? Might also be useful to include the strace of the socket-rw just in case, so maybe run it ala

strace -o foo ./socket-rw

and include foo in the reply as well.

Odd, I just ran it through strace and it exited immediately: