diff mbox series

[v2,6/6] RISC-V: selftests: Add CBO tests

Message ID 20230830164954.91987-14-ajones@ventanamicro.com (mailing list archive)
State Superseded
Headers show
Series RISC-V: Enable cbo.zero in usermode | expand

Checks

Context Check Description
conchuod/tree_selection fail Failed to apply to next/pending-fixes, riscv/for-next or riscv/master

Commit Message

Andrew Jones Aug. 30, 2023, 4:50 p.m. UTC
Add hwprobe test for Zicboz and its block size. Also, when Zicboz is
present, test that cbo.zero may be issued and works. Additionally
test that the Zicbom instructions cause SIGILL and also that cbo.zero
causes SIGILL when Zicboz is not present. Pinning the test to a subset
of cpus with taskset will also restrict the hwprobe calls to that set.

Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
---
 .../testing/selftests/riscv/hwprobe/Makefile  |   7 +-
 tools/testing/selftests/riscv/hwprobe/cbo.c   | 162 ++++++++++++++++++
 .../testing/selftests/riscv/hwprobe/hwprobe.c |  12 +-
 .../testing/selftests/riscv/hwprobe/hwprobe.h |  15 ++
 4 files changed, 184 insertions(+), 12 deletions(-)
 create mode 100644 tools/testing/selftests/riscv/hwprobe/cbo.c
 create mode 100644 tools/testing/selftests/riscv/hwprobe/hwprobe.h

Comments

Wang, Xiao W Sept. 1, 2023, 9:37 a.m. UTC | #1
Hi,

> -----Original Message-----
> From: linux-riscv <linux-riscv-bounces@lists.infradead.org> On Behalf Of
> Andrew Jones
> Sent: Thursday, August 31, 2023 12:50 AM
> To: linux-riscv@lists.infradead.org
> Cc: paul.walmsley@sifive.com; palmer@dabbelt.com;
> aou@eecs.berkeley.edu; evan@rivosinc.com; conor.dooley@microchip.com;
> apatel@ventanamicro.com
> Subject: [PATCH v2 6/6] RISC-V: selftests: Add CBO tests
> 
> Add hwprobe test for Zicboz and its block size. Also, when Zicboz is
> present, test that cbo.zero may be issued and works. Additionally
> test that the Zicbom instructions cause SIGILL and also that cbo.zero
> causes SIGILL when Zicboz is not present. Pinning the test to a subset
> of cpus with taskset will also restrict the hwprobe calls to that set.
> 
> Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
> ---
>  .../testing/selftests/riscv/hwprobe/Makefile  |   7 +-
>  tools/testing/selftests/riscv/hwprobe/cbo.c   | 162 ++++++++++++++++++
>  .../testing/selftests/riscv/hwprobe/hwprobe.c |  12 +-
>  .../testing/selftests/riscv/hwprobe/hwprobe.h |  15 ++
>  4 files changed, 184 insertions(+), 12 deletions(-)
>  create mode 100644 tools/testing/selftests/riscv/hwprobe/cbo.c
>  create mode 100644 tools/testing/selftests/riscv/hwprobe/hwprobe.h
> 
> diff --git a/tools/testing/selftests/riscv/hwprobe/Makefile
> b/tools/testing/selftests/riscv/hwprobe/Makefile
> index 5f614c3ba598..f224b84591fb 100644
> --- a/tools/testing/selftests/riscv/hwprobe/Makefile
> +++ b/tools/testing/selftests/riscv/hwprobe/Makefile
> @@ -2,9 +2,14 @@
>  # Copyright (C) 2021 ARM Limited
>  # Originally tools/testing/arm64/abi/Makefile
> 
> -TEST_GEN_PROGS := hwprobe
> +CFLAGS += -I$(top_srcdir)/tools/include
> +
> +TEST_GEN_PROGS := hwprobe cbo
> 
>  include ../../lib.mk
> 
>  $(OUTPUT)/hwprobe: hwprobe.c sys_hwprobe.S
>  	$(CC) -static -o$@ $(CFLAGS) $(LDFLAGS) $^
> +
> +$(OUTPUT)/cbo: cbo.c sys_hwprobe.S
> +	$(CC) -static -o$@ $(CFLAGS) $(LDFLAGS) $^
> diff --git a/tools/testing/selftests/riscv/hwprobe/cbo.c
> b/tools/testing/selftests/riscv/hwprobe/cbo.c
> new file mode 100644
> index 000000000000..920abfaa10c2
> --- /dev/null
> +++ b/tools/testing/selftests/riscv/hwprobe/cbo.c
> @@ -0,0 +1,162 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (c) 2023 Ventana Micro Systems Inc.
> + *
> + * Run with 'taskset -c <cpu-list> cbo' to only execute hwprobe on a
> + * subset of cpus, as well as only executing the tests on those cpus.
> + */
> +#define _GNU_SOURCE
> +#include <stdbool.h>
> +#include <stdint.h>
> +#include <sched.h>
> +#include <signal.h>
> +#include <assert.h>
> +#include <linux/compiler.h>
> +#include <asm/ucontext.h>
> +
> +#include "hwprobe.h"
> +#include "../../kselftest.h"
> +
> +static char mem[4096] __aligned(4096) = { [0 ... 4095] = 0xa5 };
> +
> +static bool illegal_insn;
> +
> +static void sigill_handler(int sig, siginfo_t *info, void *context)
> +{
> +	unsigned long *regs = (unsigned long *)&((ucontext_t *)context)-
> >uc_mcontext;
> +	uint32_t insn = *(uint32_t *)regs[0];
> +
> +	assert(insn >> 20 == regs[11] &&
> +	       (insn & ((1 << 20) - 1)) == (10 << 15 | 2 << 12 | 0 << 7 | 15));
> +
> +	illegal_insn = true;
> +	regs[0] += 4;
> +}
> +
> +static void cbo_insn(int fn, char *base)
> +{
> +	asm volatile(
> +	"mv	a0, %0\n"
> +	"li	a1, %1\n"
> +	".4byte	%1 << 20 | 10 << 15 | 2 << 12 | 0 << 7 | 15\n"
> +	: : "r" (base), "i" (fn) : "a0", "a1", "memory");
> +}
> +
> +static void cbo_inval(char *base) { cbo_insn(0, base); }
> +static void cbo_clean(char *base) { cbo_insn(1, base); }
> +static void cbo_flush(char *base) { cbo_insn(2, base); }
> +static void cbo_zero(char *base)  { cbo_insn(4, base); }
> +
> +static void test_no_zicbom(void)
> +{
> +	illegal_insn = false;
> +	cbo_clean(&mem[0]);
> +	ksft_test_result(illegal_insn, "No cbo.clean\n");
> +
> +	illegal_insn = false;
> +	cbo_flush(&mem[0]);
> +	ksft_test_result(illegal_insn, "No cbo.flush\n");
> +
> +	illegal_insn = false;
> +	cbo_inval(&mem[0]);
> +	ksft_test_result(illegal_insn, "No cbo.inval\n");
> +}
> +
> +static void test_no_zicboz(void)
> +{
> +	illegal_insn = false;
> +	cbo_clean(&mem[0]);

Seems we need to call cbo_zero() instead of cbo_clean().

BRs,
Xiao

> +	ksft_test_result(illegal_insn, "No cbo.zero\n");
> +}
> +
[...]
> 
> 
> _______________________________________________
> linux-riscv mailing list
> linux-riscv@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-riscv
Andrew Jones Sept. 1, 2023, 3:12 p.m. UTC | #2
On Fri, Sep 01, 2023 at 09:37:27AM +0000, Wang, Xiao W wrote:
> Hi,
> 
> > -----Original Message-----
> > From: linux-riscv <linux-riscv-bounces@lists.infradead.org> On Behalf Of
> > Andrew Jones
> > Sent: Thursday, August 31, 2023 12:50 AM
> > To: linux-riscv@lists.infradead.org
> > Cc: paul.walmsley@sifive.com; palmer@dabbelt.com;
> > aou@eecs.berkeley.edu; evan@rivosinc.com; conor.dooley@microchip.com;
> > apatel@ventanamicro.com
> > Subject: [PATCH v2 6/6] RISC-V: selftests: Add CBO tests
> > 
> > Add hwprobe test for Zicboz and its block size. Also, when Zicboz is
> > present, test that cbo.zero may be issued and works. Additionally
> > test that the Zicbom instructions cause SIGILL and also that cbo.zero
> > causes SIGILL when Zicboz is not present. Pinning the test to a subset
> > of cpus with taskset will also restrict the hwprobe calls to that set.
> > 
> > Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
> > ---
> >  .../testing/selftests/riscv/hwprobe/Makefile  |   7 +-
> >  tools/testing/selftests/riscv/hwprobe/cbo.c   | 162 ++++++++++++++++++
> >  .../testing/selftests/riscv/hwprobe/hwprobe.c |  12 +-
> >  .../testing/selftests/riscv/hwprobe/hwprobe.h |  15 ++
> >  4 files changed, 184 insertions(+), 12 deletions(-)
> >  create mode 100644 tools/testing/selftests/riscv/hwprobe/cbo.c
> >  create mode 100644 tools/testing/selftests/riscv/hwprobe/hwprobe.h
> > 
> > diff --git a/tools/testing/selftests/riscv/hwprobe/Makefile
> > b/tools/testing/selftests/riscv/hwprobe/Makefile
> > index 5f614c3ba598..f224b84591fb 100644
> > --- a/tools/testing/selftests/riscv/hwprobe/Makefile
> > +++ b/tools/testing/selftests/riscv/hwprobe/Makefile
> > @@ -2,9 +2,14 @@
> >  # Copyright (C) 2021 ARM Limited
> >  # Originally tools/testing/arm64/abi/Makefile
> > 
> > -TEST_GEN_PROGS := hwprobe
> > +CFLAGS += -I$(top_srcdir)/tools/include
> > +
> > +TEST_GEN_PROGS := hwprobe cbo
> > 
> >  include ../../lib.mk
> > 
> >  $(OUTPUT)/hwprobe: hwprobe.c sys_hwprobe.S
> >  	$(CC) -static -o$@ $(CFLAGS) $(LDFLAGS) $^
> > +
> > +$(OUTPUT)/cbo: cbo.c sys_hwprobe.S
> > +	$(CC) -static -o$@ $(CFLAGS) $(LDFLAGS) $^
> > diff --git a/tools/testing/selftests/riscv/hwprobe/cbo.c
> > b/tools/testing/selftests/riscv/hwprobe/cbo.c
> > new file mode 100644
> > index 000000000000..920abfaa10c2
> > --- /dev/null
> > +++ b/tools/testing/selftests/riscv/hwprobe/cbo.c
> > @@ -0,0 +1,162 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * Copyright (c) 2023 Ventana Micro Systems Inc.
> > + *
> > + * Run with 'taskset -c <cpu-list> cbo' to only execute hwprobe on a
> > + * subset of cpus, as well as only executing the tests on those cpus.
> > + */
> > +#define _GNU_SOURCE
> > +#include <stdbool.h>
> > +#include <stdint.h>
> > +#include <sched.h>
> > +#include <signal.h>
> > +#include <assert.h>
> > +#include <linux/compiler.h>
> > +#include <asm/ucontext.h>
> > +
> > +#include "hwprobe.h"
> > +#include "../../kselftest.h"
> > +
> > +static char mem[4096] __aligned(4096) = { [0 ... 4095] = 0xa5 };
> > +
> > +static bool illegal_insn;
> > +
> > +static void sigill_handler(int sig, siginfo_t *info, void *context)
> > +{
> > +	unsigned long *regs = (unsigned long *)&((ucontext_t *)context)-
> > >uc_mcontext;
> > +	uint32_t insn = *(uint32_t *)regs[0];
> > +
> > +	assert(insn >> 20 == regs[11] &&
> > +	       (insn & ((1 << 20) - 1)) == (10 << 15 | 2 << 12 | 0 << 7 | 15));
> > +
> > +	illegal_insn = true;
> > +	regs[0] += 4;
> > +}
> > +
> > +static void cbo_insn(int fn, char *base)
> > +{
> > +	asm volatile(
> > +	"mv	a0, %0\n"
> > +	"li	a1, %1\n"
> > +	".4byte	%1 << 20 | 10 << 15 | 2 << 12 | 0 << 7 | 15\n"
> > +	: : "r" (base), "i" (fn) : "a0", "a1", "memory");
> > +}
> > +
> > +static void cbo_inval(char *base) { cbo_insn(0, base); }
> > +static void cbo_clean(char *base) { cbo_insn(1, base); }
> > +static void cbo_flush(char *base) { cbo_insn(2, base); }
> > +static void cbo_zero(char *base)  { cbo_insn(4, base); }
> > +
> > +static void test_no_zicbom(void)
> > +{
> > +	illegal_insn = false;
> > +	cbo_clean(&mem[0]);
> > +	ksft_test_result(illegal_insn, "No cbo.clean\n");
> > +
> > +	illegal_insn = false;
> > +	cbo_flush(&mem[0]);
> > +	ksft_test_result(illegal_insn, "No cbo.flush\n");
> > +
> > +	illegal_insn = false;
> > +	cbo_inval(&mem[0]);
> > +	ksft_test_result(illegal_insn, "No cbo.inval\n");
> > +}
> > +
> > +static void test_no_zicboz(void)
> > +{
> > +	illegal_insn = false;
> > +	cbo_clean(&mem[0]);
> 
> Seems we need to call cbo_zero() instead of cbo_clean().

Nice catch, Xiao. Copy+paste mistake... Will fix for v3.

Thanks,
drew

> 
> BRs,
> Xiao
> 
> > +	ksft_test_result(illegal_insn, "No cbo.zero\n");
> > +}
> > +
> [...]
> > 
> > 
> > _______________________________________________
> > linux-riscv mailing list
> > linux-riscv@lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/linux-riscv
diff mbox series

Patch

diff --git a/tools/testing/selftests/riscv/hwprobe/Makefile b/tools/testing/selftests/riscv/hwprobe/Makefile
index 5f614c3ba598..f224b84591fb 100644
--- a/tools/testing/selftests/riscv/hwprobe/Makefile
+++ b/tools/testing/selftests/riscv/hwprobe/Makefile
@@ -2,9 +2,14 @@ 
 # Copyright (C) 2021 ARM Limited
 # Originally tools/testing/arm64/abi/Makefile
 
-TEST_GEN_PROGS := hwprobe
+CFLAGS += -I$(top_srcdir)/tools/include
+
+TEST_GEN_PROGS := hwprobe cbo
 
 include ../../lib.mk
 
 $(OUTPUT)/hwprobe: hwprobe.c sys_hwprobe.S
 	$(CC) -static -o$@ $(CFLAGS) $(LDFLAGS) $^
+
+$(OUTPUT)/cbo: cbo.c sys_hwprobe.S
+	$(CC) -static -o$@ $(CFLAGS) $(LDFLAGS) $^
diff --git a/tools/testing/selftests/riscv/hwprobe/cbo.c b/tools/testing/selftests/riscv/hwprobe/cbo.c
new file mode 100644
index 000000000000..920abfaa10c2
--- /dev/null
+++ b/tools/testing/selftests/riscv/hwprobe/cbo.c
@@ -0,0 +1,162 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2023 Ventana Micro Systems Inc.
+ *
+ * Run with 'taskset -c <cpu-list> cbo' to only execute hwprobe on a
+ * subset of cpus, as well as only executing the tests on those cpus.
+ */
+#define _GNU_SOURCE
+#include <stdbool.h>
+#include <stdint.h>
+#include <sched.h>
+#include <signal.h>
+#include <assert.h>
+#include <linux/compiler.h>
+#include <asm/ucontext.h>
+
+#include "hwprobe.h"
+#include "../../kselftest.h"
+
+static char mem[4096] __aligned(4096) = { [0 ... 4095] = 0xa5 };
+
+static bool illegal_insn;
+
+static void sigill_handler(int sig, siginfo_t *info, void *context)
+{
+	unsigned long *regs = (unsigned long *)&((ucontext_t *)context)->uc_mcontext;
+	uint32_t insn = *(uint32_t *)regs[0];
+
+	assert(insn >> 20 == regs[11] &&
+	       (insn & ((1 << 20) - 1)) == (10 << 15 | 2 << 12 | 0 << 7 | 15));
+
+	illegal_insn = true;
+	regs[0] += 4;
+}
+
+static void cbo_insn(int fn, char *base)
+{
+	asm volatile(
+	"mv	a0, %0\n"
+	"li	a1, %1\n"
+	".4byte	%1 << 20 | 10 << 15 | 2 << 12 | 0 << 7 | 15\n"
+	: : "r" (base), "i" (fn) : "a0", "a1", "memory");
+}
+
+static void cbo_inval(char *base) { cbo_insn(0, base); }
+static void cbo_clean(char *base) { cbo_insn(1, base); }
+static void cbo_flush(char *base) { cbo_insn(2, base); }
+static void cbo_zero(char *base)  { cbo_insn(4, base); }
+
+static void test_no_zicbom(void)
+{
+	illegal_insn = false;
+	cbo_clean(&mem[0]);
+	ksft_test_result(illegal_insn, "No cbo.clean\n");
+
+	illegal_insn = false;
+	cbo_flush(&mem[0]);
+	ksft_test_result(illegal_insn, "No cbo.flush\n");
+
+	illegal_insn = false;
+	cbo_inval(&mem[0]);
+	ksft_test_result(illegal_insn, "No cbo.inval\n");
+}
+
+static void test_no_zicboz(void)
+{
+	illegal_insn = false;
+	cbo_clean(&mem[0]);
+	ksft_test_result(illegal_insn, "No cbo.zero\n");
+}
+
+static bool is_power_of_2(__u64 n)
+{
+	return n != 0 && (n & (n - 1)) == 0;
+}
+
+static void test_zicboz(__u64 block_size)
+{
+	int i, j;
+
+	illegal_insn = false;
+	cbo_zero(&mem[block_size]);
+	ksft_test_result(!illegal_insn, "cbo.zero\n");
+
+	if (!is_power_of_2(block_size)) {
+		ksft_test_result_skip("cbo.zero check\n");
+		return;
+	}
+
+	assert(block_size <= 1024);
+
+	for (i = 0; i < 4096 / block_size; ++i) {
+		if (i % 2)
+			cbo_zero(&mem[i * block_size]);
+	}
+
+	for (i = 0; i < 4096 / block_size; ++i) {
+		char expected = i % 2 ? 0x0 : 0xa5;
+
+		for (j = 0; j < block_size; ++j) {
+			if (mem[i * block_size + j] != expected) {
+				ksft_test_result_fail("cbo.zero check\n");
+				ksft_print_msg("cbo.zero check: mem[%d] != 0x%x\n",
+					       i * block_size + j, expected);
+				return;
+			}
+		}
+	}
+
+	ksft_test_result_pass("cbo.zero check\n");
+}
+
+int main(int argc, char **argv)
+{
+	struct sigaction act = {
+		.sa_sigaction = &sigill_handler,
+		.sa_flags = SA_SIGINFO,
+	};
+	bool has_zicboz = false;
+	struct riscv_hwprobe pair;
+	cpu_set_t cpus;
+	size_t nr_cpus;
+	long rc;
+
+	rc = sigaction(SIGILL, &act, NULL);
+	assert(rc == 0);
+
+	rc = sched_getaffinity(0, sizeof(cpu_set_t), &cpus);
+	assert(rc == 0);
+	nr_cpus = CPU_COUNT(&cpus);
+
+	ksft_print_header();
+
+	pair.key = RISCV_HWPROBE_KEY_IMA_EXT_0;
+	rc = riscv_hwprobe(&pair, 1, nr_cpus, (unsigned long *)&cpus, 0);
+	if (rc < 0)
+		ksft_exit_fail_msg("hwprobe() failed with %d\n", rc);
+
+	if (pair.key != -1 && (pair.value & RISCV_HWPROBE_EXT_ZICBOZ)) {
+		has_zicboz = true;
+		ksft_set_plan(6);
+	} else {
+		ksft_print_msg("No Zicboz, testing cbo.zero remains privileged\n");
+		ksft_set_plan(4);
+	}
+
+	/* Ensure zicbom instructions remain privileged */
+	test_no_zicbom();
+
+	if (has_zicboz) {
+		pair.key = RISCV_HWPROBE_KEY_ZICBOZ_BLOCK_SIZE;
+		rc = riscv_hwprobe(&pair, 1, nr_cpus, (unsigned long *)&cpus, 0);
+		ksft_test_result(rc == 0 && pair.key == RISCV_HWPROBE_KEY_ZICBOZ_BLOCK_SIZE &&
+				 is_power_of_2(pair.value), "Zicboz block size\n");
+		ksft_print_msg("Zicboz block size: %ld\n", pair.value);
+		test_zicboz(pair.value);
+	} else {
+		test_no_zicboz();
+	}
+
+	ksft_finished();
+}
diff --git a/tools/testing/selftests/riscv/hwprobe/hwprobe.c b/tools/testing/selftests/riscv/hwprobe/hwprobe.c
index 4f15f1f3b4c3..c474891df307 100644
--- a/tools/testing/selftests/riscv/hwprobe/hwprobe.c
+++ b/tools/testing/selftests/riscv/hwprobe/hwprobe.c
@@ -1,17 +1,7 @@ 
 // SPDX-License-Identifier: GPL-2.0-only
-#include <stddef.h>
-#include <asm/hwprobe.h>
-
+#include "hwprobe.h"
 #include "../../kselftest.h"
 
-/*
- * Rather than relying on having a new enough libc to define this, just do it
- * ourselves.  This way we don't need to be coupled to a new-enough libc to
- * contain the call.
- */
-long riscv_hwprobe(struct riscv_hwprobe *pairs, size_t pair_count,
-		   size_t cpu_count, unsigned long *cpus, unsigned int flags);
-
 int main(int argc, char **argv)
 {
 	struct riscv_hwprobe pairs[8];
diff --git a/tools/testing/selftests/riscv/hwprobe/hwprobe.h b/tools/testing/selftests/riscv/hwprobe/hwprobe.h
new file mode 100644
index 000000000000..721b0ce73a56
--- /dev/null
+++ b/tools/testing/selftests/riscv/hwprobe/hwprobe.h
@@ -0,0 +1,15 @@ 
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef SELFTEST_RISCV_HWPROBE_H
+#define SELFTEST_RISCV_HWPROBE_H
+#include <stddef.h>
+#include <asm/hwprobe.h>
+
+/*
+ * Rather than relying on having a new enough libc to define this, just do it
+ * ourselves.  This way we don't need to be coupled to a new-enough libc to
+ * contain the call.
+ */
+long riscv_hwprobe(struct riscv_hwprobe *pairs, size_t pair_count,
+		   size_t cpu_count, unsigned long *cpus, unsigned int flags);
+
+#endif