[PATCH v1 2/4] kselftest/arm64: Count SIGUSR2 deliveries in FP stress tests

[Mark Brown <broonie@kernel.org>]

Currently the floating point stress tests mostly support testing that the
data they are checking can be disrupted from a signal handler triggered by
SIGUSR1. This is not properly implemented for all the tests and in testing
is frequently modified to just handle the signal without corrupting data in
order to ensure that signal handling does not corrupt data. Directly support
this usage by installing a SIGUSR2 handler which simply counts the signal
delivery.

Signed-off-by: Mark Brown <broonie@kernel.org>
---
 tools/testing/selftests/arm64/fp/asm-offsets.h |  1 +
 tools/testing/selftests/arm64/fp/fpsimd-test.S | 15 +++++++++++++++
 tools/testing/selftests/arm64/fp/sve-test.S    | 15 +++++++++++++++
 tools/testing/selftests/arm64/fp/za-test.S     | 15 +++++++++++++++
 4 files changed, 46 insertions(+)

diff --git a/tools/testing/selftests/arm64/fp/asm-offsets.h b/tools/testing/selftests/arm64/fp/asm-offsets.h
index a180851496ec..757b2fd75dd7 100644
--- a/tools/testing/selftests/arm64/fp/asm-offsets.h
+++ b/tools/testing/selftests/arm64/fp/asm-offsets.h
@@ -3,6 +3,7 @@
 #define sa_handler 0
 #define sa_mask_sz 8
 #define SIGUSR1 10
+#define SIGUSR2 12
 #define SIGTERM 15
 #define SIGINT 2
 #define SIGABRT 6
diff --git a/tools/testing/selftests/arm64/fp/fpsimd-test.S b/tools/testing/selftests/arm64/fp/fpsimd-test.S
index e21e8ea52c7e..f0f92192351a 100644
--- a/tools/testing/selftests/arm64/fp/fpsimd-test.S
+++ b/tools/testing/selftests/arm64/fp/fpsimd-test.S
@@ -151,6 +151,15 @@ function irritator_handler
 	ret
 endfunction
 
+function tickle_handler
+	// Increment the signal count (x23):
+	ldr	x0, [x2, #ucontext_regs + 8 * 23]
+	add	x0, x0, #1
+	str	x0, [x2, #ucontext_regs + 8 * 23]
+
+	ret
+endfunction
+
 function terminate_handler
 	mov	w21, w0
 	mov	x20, x2
@@ -255,6 +264,12 @@ _start:
 	orr	w2, w2, #SA_NODEFER
 	bl	setsignal
 
+	mov	w0, #SIGUSR2
+	adr	x1, tickle_handler
+	mov	w2, #SA_SIGINFO
+	orr	w2, w2, #SA_NODEFER
+	bl	setsignal
+
 	mov	x22, #0		// generation number, increments per iteration
 .Ltest_loop:
 
diff --git a/tools/testing/selftests/arm64/fp/sve-test.S b/tools/testing/selftests/arm64/fp/sve-test.S
index 589264231a2d..79c56e6c5b23 100644
--- a/tools/testing/selftests/arm64/fp/sve-test.S
+++ b/tools/testing/selftests/arm64/fp/sve-test.S
@@ -314,6 +314,15 @@ function irritator_handler
 	ret
 endfunction
 
+function tickle_handler
+	// Increment the signal count (x23):
+	ldr	x0, [x2, #ucontext_regs + 8 * 23]
+	add	x0, x0, #1
+	str	x0, [x2, #ucontext_regs + 8 * 23]
+
+	ret
+endfunction
+
 function terminate_handler
 	mov	w21, w0
 	mov	x20, x2
@@ -423,6 +432,12 @@ _start:
 	orr	w2, w2, #SA_NODEFER
 	bl	setsignal
 
+	mov	w0, #SIGUSR2
+	adr	x1, tickle_handler
+	mov	w2, #SA_SIGINFO
+	orr	w2, w2, #SA_NODEFER
+	bl	setsignal
+
 #ifdef SSVE
 	smstart_sm		// syscalls will have exited streaming mode
 #endif
diff --git a/tools/testing/selftests/arm64/fp/za-test.S b/tools/testing/selftests/arm64/fp/za-test.S
index 2dd358f9edf2..901839107205 100644
--- a/tools/testing/selftests/arm64/fp/za-test.S
+++ b/tools/testing/selftests/arm64/fp/za-test.S
@@ -167,6 +167,15 @@ function irritator_handler
 	ret
 endfunction
 
+function tickle_handler
+	// Increment the signal count (x23):
+	ldr	x0, [x2, #ucontext_regs + 8 * 23]
+	add	x0, x0, #1
+	str	x0, [x2, #ucontext_regs + 8 * 23]
+
+	ret
+endfunction
+
 function terminate_handler
 	mov	w21, w0
 	mov	x20, x2
@@ -273,6 +282,12 @@ _start:
 	orr	w2, w2, #SA_NODEFER
 	bl	setsignal
 
+	mov	w0, #SIGUSR2
+	adr	x1, tickle_handler
+	mov	w2, #SA_SIGINFO
+	orr	w2, w2, #SA_NODEFER
+	bl	setsignal
+
 	mov	x22, #0		// generation number, increments per iteration
 .Ltest_loop:
 	rdsvl	0, 8
-- 
2.30.2