Following the pattern for the other register sets add a stress test program for ZT0 which continually loads and verifies patterns in the register in an effort to discover context switching problems.
Signed-off-by: Mark Brown broonie@kernel.org --- tools/testing/selftests/arm64/fp/.gitignore | 1 + tools/testing/selftests/arm64/fp/Makefile | 3 + tools/testing/selftests/arm64/fp/sme-inst.h | 20 ++ tools/testing/selftests/arm64/fp/zt-test.S | 324 ++++++++++++++++++++ 4 files changed, 348 insertions(+) create mode 100644 tools/testing/selftests/arm64/fp/zt-test.S
diff --git a/tools/testing/selftests/arm64/fp/.gitignore b/tools/testing/selftests/arm64/fp/.gitignore index df79d29664a1..41bde4c97d47 100644 --- a/tools/testing/selftests/arm64/fp/.gitignore +++ b/tools/testing/selftests/arm64/fp/.gitignore @@ -12,3 +12,4 @@ vlset za-fork za-ptrace za-test +zt-test diff --git a/tools/testing/selftests/arm64/fp/Makefile b/tools/testing/selftests/arm64/fp/Makefile index 36db61358ed5..aff3026d3dff 100644 --- a/tools/testing/selftests/arm64/fp/Makefile +++ b/tools/testing/selftests/arm64/fp/Makefile @@ -14,6 +14,7 @@ TEST_GEN_PROGS_EXTENDED := fp-pidbench fpsimd-test \ sve-test \ ssve-test \ za-test \ + zt-test \ vlset TEST_PROGS_EXTENDED := fpsimd-stress sve-stress ssve-stress za-stress
@@ -41,5 +42,7 @@ $(OUTPUT)/za-fork: za-fork.c $(OUTPUT)/za-fork-asm.o $(OUTPUT)/za-ptrace: za-ptrace.c $(OUTPUT)/za-test: za-test.S $(OUTPUT)/asm-utils.o $(CC) -nostdlib $^ -o $@ +$(OUTPUT)/zt-test: zt-test.S $(OUTPUT)/asm-utils.o + $(CC) -nostdlib $^ -o $@
include ../../lib.mk diff --git a/tools/testing/selftests/arm64/fp/sme-inst.h b/tools/testing/selftests/arm64/fp/sme-inst.h index 7191e53ca1c0..9292bba5400b 100644 --- a/tools/testing/selftests/arm64/fp/sme-inst.h +++ b/tools/testing/selftests/arm64/fp/sme-inst.h @@ -48,4 +48,24 @@ | ((\offset) & 7) .endm
+/* + * LDR (ZT0) + * + * LDR ZT0, nx + */ +.macro _ldr_zt nx + .inst 0xe11f8000 \ + | (((\nx) & 0x1f) << 5) +.endm + +/* + * STR (ZT0) + * + * STR ZT0, nx + */ +.macro _str_zt nx + .inst 0xe13f8000 \ + | (((\nx) & 0x1f) << 5) +.endm + #endif diff --git a/tools/testing/selftests/arm64/fp/zt-test.S b/tools/testing/selftests/arm64/fp/zt-test.S new file mode 100644 index 000000000000..6f04a8bf60f6 --- /dev/null +++ b/tools/testing/selftests/arm64/fp/zt-test.S @@ -0,0 +1,324 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (C) 2021-2 ARM Limited. +// Original author: Mark Brown broonie@kernel.org +// +// Scalable Matrix Extension ZT context switch test +// Repeatedly writes unique test patterns into ZT0 +// and reads them back to verify integrity. + +#include <asm/unistd.h> +#include "assembler.h" +#include "asm-offsets.h" +#include "sme-inst.h" + +.arch_extension sve + +#define ZT_SZ 512 +#define ZT_B (ZT_SZ / 8) + +// Declare some storage space to shadow ZT register contents and a +// scratch buffer. +.pushsection .text +.data +.align 4 +ztref: + .space ZT_B +scratch: + .space ZT_B +.popsection + +// Trivial memory copy: copy x2 bytes, starting at address x1, to address x0. +// Clobbers x0-x3 +function memcpy + cmp x2, #0 + b.eq 1f +0: ldrb w3, [x1], #1 + strb w3, [x0], #1 + subs x2, x2, #1 + b.ne 0b +1: ret +endfunction + +// Generate a test pattern for storage in ZT +// x0: pid +// x1: generation + +// These values are used to constuct a 32-bit pattern that is repeated in the +// scratch buffer as many times as will fit: +// bits 31:24 generation number (increments once per test_loop) +// bits 23: 8 pid +// bits 7: 0 32-bit lane index + +function pattern + mov w3, wzr + bfi w3, w0, #8, #16 // PID + bfi w3, w1, #24, #8 // Generation + + ldr x0, =scratch + mov w1, #ZT_B / 4 + +0: str w3, [x0], #4 + add w3, w3, #1 // Lane + subs w1, w1, #1 + b.ne 0b + + ret +endfunction + +// Set up test pattern in a ZT horizontal vector +// x0: pid +// x1: generation +function setup_zt + mov x4, x30 + + bl pattern // Get pattern in scratch buffer + ldr x0, =ztref + ldr x1, =scratch + mov x2, #ZT_B + bl memcpy + + _ldr_zt 0 // load zt0 from pointer x0 + + ret x4 +endfunction + +// Trivial memory compare: compare x2 bytes starting at address x0 with +// bytes starting at address x1. +// Returns only if all bytes match; otherwise, the program is aborted. +// Clobbers x0-x5. +function memcmp + cbz x2, 2f + + stp x0, x1, [sp, #-0x20]! + str x2, [sp, #0x10] + + mov x5, #0 +0: ldrb w3, [x0, x5] + ldrb w4, [x1, x5] + add x5, x5, #1 + cmp w3, w4 + b.ne 1f + subs x2, x2, #1 + b.ne 0b + +1: ldr x2, [sp, #0x10] + ldp x0, x1, [sp], #0x20 + b.ne barf + +2: ret +endfunction + +// Verify that a ZT vector matches its shadow in memory, else abort +// Clobbers x0-x7 and x12. +function check_zt + mov x3, x30 + + ldr x0, =scratch // Poison scratch + mov x1, #ZT_B + bl memfill_ae + + ldr x0, =scratch + _str_zt 0 + + ldr x0, =ztref + ldr x1, =scratch + mov x2, #ZT_B + mov x30, x3 + b memcmp +endfunction + +// Any SME register modified here can cause corruption in the main +// thread -- but *only* the locations modified here. +function irritator_handler + // Increment the irritation signal count (x23): + ldr x0, [x2, #ucontext_regs + 8 * 23] + add x0, x0, #1 + str x0, [x2, #ucontext_regs + 8 * 23] + + // Corrupt some random ZT data +#if 0 + adr x0, .text + (irritator_handler - .text) / 16 * 16 + movi v0.8b, #1 + movi v9.16b, #2 + movi v31.8b, #3 +#endif + + 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 + + puts "Terminated by signal " + mov w0, w21 + bl putdec + puts ", no error, iterations=" + ldr x0, [x20, #ucontext_regs + 8 * 22] + bl putdec + puts ", signals=" + ldr x0, [x20, #ucontext_regs + 8 * 23] + bl putdecn + + mov x0, #0 + mov x8, #__NR_exit + svc #0 +endfunction + +// w0: signal number +// x1: sa_action +// w2: sa_flags +// Clobbers x0-x6,x8 +function setsignal + str x30, [sp, #-((sa_sz + 15) / 16 * 16 + 16)]! + + mov w4, w0 + mov x5, x1 + mov w6, w2 + + add x0, sp, #16 + mov x1, #sa_sz + bl memclr + + mov w0, w4 + add x1, sp, #16 + str w6, [x1, #sa_flags] + str x5, [x1, #sa_handler] + mov x2, #0 + mov x3, #sa_mask_sz + mov x8, #__NR_rt_sigaction + svc #0 + + cbz w0, 1f + + puts "sigaction failure\n" + b .Labort + +1: ldr x30, [sp], #((sa_sz + 15) / 16 * 16 + 16) + ret +endfunction + +// Main program entry point +.globl _start +function _start +_start: + mov x23, #0 // signal count + + mov w0, #SIGINT + adr x1, terminate_handler + mov w2, #SA_SIGINFO + bl setsignal + + mov w0, #SIGTERM + adr x1, terminate_handler + mov w2, #SA_SIGINFO + bl setsignal + + mov w0, #SIGUSR1 + adr x1, irritator_handler + mov w2, #SA_SIGINFO + 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 + + smstart_za + + // Obtain our PID, to ensure test pattern uniqueness between processes + mov x8, #__NR_getpid + svc #0 + mov x20, x0 + + puts "PID:\t" + mov x0, x20 + bl putdecn + + mov x22, #0 // generation number, increments per iteration +.Ltest_loop: + mov x0, x20 + mov x1, x22 + bl setup_zt + + mov x8, #__NR_sched_yield // Encourage preemption + svc #0 + + mov x0, x20 + mov x1, x22 + bl check_zt + + add x22, x22, #1 // Everything still working + b .Ltest_loop + +.Labort: + mov x0, #0 + mov x1, #SIGABRT + mov x8, #__NR_kill + svc #0 +endfunction + +function barf +// fpsimd.c acitivty log dump hack +// ldr w0, =0xdeadc0de +// mov w8, #__NR_exit +// svc #0 +// end hack + smstop + mov x10, x0 // expected data + mov x11, x1 // actual data + mov x12, x2 // data size + + puts "Mismatch: PID=" + mov x0, x20 + bl putdec + puts ", iteration=" + mov x0, x22 + bl putdec + puts "\tExpected [" + mov x0, x10 + mov x1, x12 + bl dumphex + puts "]\n\tGot [" + mov x0, x11 + mov x1, x12 + bl dumphex + puts "]\n" + + mov x8, #__NR_getpid + svc #0 +// fpsimd.c acitivty log dump hack +// ldr w0, =0xdeadc0de +// mov w8, #__NR_exit +// svc #0 +// ^ end of hack + mov x1, #SIGABRT + mov x8, #__NR_kill + svc #0 +// mov x8, #__NR_exit +// mov x1, #1 +// svc #0 +endfunction + +function svcr_barf + mov x10, x0 + + puts "Bad SVCR: " + mov x0, x10 + bl putdecn + + mov x8, #__NR_exit + mov x1, #1 + svc #0 +endfunction