From patchwork Wed Oct 27 18:44:17 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 12587845 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 18152C433F5 for ; Wed, 27 Oct 2021 18:52:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E852061039 for ; Wed, 27 Oct 2021 18:52:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243648AbhJ0Syr (ORCPT ); Wed, 27 Oct 2021 14:54:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:34168 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240514AbhJ0Syq (ORCPT ); Wed, 27 Oct 2021 14:54:46 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 0740A60F38; Wed, 27 Oct 2021 18:52:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1635360740; bh=fs6Mo/cNVCXgit6VI25SiK2O86CoOZYuGBLTQAR7ou4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uuXY3hgdZbQvNn/xsCH/19sQGghCkfnOJfYTTBU0sLfUTZ8bltkCbKHb0zDOQIkhX 5JMUsP8ezAUzfFCzi6ABajNdAPp9QmV2noSrvyNnT39WW0UHL9IaAmcfIesD2oxvbK EBqbUcckB1BHMIhsRWkg0t2ZF+foEuXi8S8JIkl+FUGqUmsU95Z/zwr5aQXAU4FKu3 VEFLbci8xoNPd6E3+zd+HkMdrgUkAwSNpaLlpq6MhOuKLH3G4hnmflfpl003t9L/Bm aMUkBh6puP8AC3Eowdf6f3vAMORj084ZimfTGjc2/sn8AvqLqGE0XwWt8yBqp7I0wE bn1LhpsGiy/KQ== From: Mark Brown To: Catalin Marinas , Will Deacon , Shuah Khan , Shuah Khan Cc: Alan Hayward , Luis Machado , Salil Akerkar , Basant Kumar Dwivedi , Szabolcs Nagy , linux-arm-kernel@lists.infradead.org, linux-kselftest@vger.kernel.org, Mark Brown Subject: [PATCH v5 31/38] kselftest/arm64: Add tests for TPIDR2 Date: Wed, 27 Oct 2021 19:44:17 +0100 Message-Id: <20211027184424.166237-32-broonie@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20211027184424.166237-1-broonie@kernel.org> References: <20211027184424.166237-1-broonie@kernel.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=8971; h=from:subject; bh=fs6Mo/cNVCXgit6VI25SiK2O86CoOZYuGBLTQAR7ou4=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBheZ3+YfrKO9wqrVDyN1/vTE4zIqML+ldRAu4nWsi8 L63DQwiJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCYXmd/gAKCRAk1otyXVSH0A9WCA CDjb779U5u4HCGnsu+eJa8fMDMHYpAcrf1WDhn5WO4MBr8Itw3gWXkbl6w1T6k4TA/cLe15a7vvEml sywpd2CD3Z1hM6B5FGelR23sNxpHZ0W39CimdEr9oVYAUik/YB2i8d011LKV8Smyik+JljssKqfNrd xsImoac2pgrpzd/xxq04wyOjDqYiEcHoZVuH0qFbdu+Gogwyhv/3WyVSgOocdOf6cvBEaqeYwqpxRh Zjbc1lu8nLZuTEeGS3ug4VpLQiR3RG4V/RCXlYj6csBMnzKdNm9iA9pYT5CZmBUgbeap+Y6j9bVAP2 m6seZ7uan9483d6H0E6wtI2ZRV7uXh X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org The Scalable Matrix Extension adds a new system register TPIDR2 intended to be used by libc for its own thread specific use, add some kselftests which exercise the ABI for it. Since this test should with some adjustment work for TPIDR and any other similar registers added in future add tests for it in a separate directory rather than placing it with the other floating point tests, nothing existing looked suitable so I created a new test directory called "abi". Since this feature is intended to be used by libc the test is built as freestanding code using nolibc so we don't end up with the test program and libc both trying to manage the register simultaneously and distrupting each other. As a result of being written using nolibc rather than using hwcaps to identify if SME is available in the system we check for the default SME vector length configuration in proc, adding hwcap support to nolibc seems like disproportionate effort and didn't feel entirely idiomatic for what nolibc is trying to do. Signed-off-by: Mark Brown --- tools/testing/selftests/arm64/abi/.gitignore | 1 + tools/testing/selftests/arm64/abi/Makefile | 9 +- tools/testing/selftests/arm64/abi/tpidr2.c | 298 +++++++++++++++++++ 3 files changed, 307 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/arm64/abi/tpidr2.c diff --git a/tools/testing/selftests/arm64/abi/.gitignore b/tools/testing/selftests/arm64/abi/.gitignore index b79cf5814c23..b9e54417250d 100644 --- a/tools/testing/selftests/arm64/abi/.gitignore +++ b/tools/testing/selftests/arm64/abi/.gitignore @@ -1 +1,2 @@ syscall-abi +tpidr2 diff --git a/tools/testing/selftests/arm64/abi/Makefile b/tools/testing/selftests/arm64/abi/Makefile index 96eba974ac8d..c8d7f2495eb2 100644 --- a/tools/testing/selftests/arm64/abi/Makefile +++ b/tools/testing/selftests/arm64/abi/Makefile @@ -1,8 +1,15 @@ # SPDX-License-Identifier: GPL-2.0 # Copyright (C) 2021 ARM Limited -TEST_GEN_PROGS := syscall-abi +TEST_GEN_PROGS := syscall-abi tpidr2 include ../../lib.mk $(OUTPUT)/syscall-abi: syscall-abi.c syscall-abi-asm.S + +# Build with nolibc since TPIDR2 is intended to be actively managed by +# libc and we're trying to test the functionality that it depends on here. +$(OUTPUT)/tpidr2: tpidr2.c + $(CC) -fno-asynchronous-unwind-tables -fno-ident -s -Os -nostdlib \ + -static -include ../../../../include/nolibc/nolibc.h \ + -ffreestanding -Wall $^ -o $@ -lgcc diff --git a/tools/testing/selftests/arm64/abi/tpidr2.c b/tools/testing/selftests/arm64/abi/tpidr2.c new file mode 100644 index 000000000000..351a098b503a --- /dev/null +++ b/tools/testing/selftests/arm64/abi/tpidr2.c @@ -0,0 +1,298 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include +#include + +#define SYS_TPIDR2 "S3_3_C13_C0_5" + +#define EXPECTED_TESTS 5 + +static void putstr(const char *str) +{ + write(1, str, strlen(str)); +} + +static void putnum(unsigned int num) +{ + char c; + + if (num / 10) + putnum(num / 10); + + c = '0' + (num % 10); + write(1, &c, 1); +} + +static int tests_run; +static int tests_passed; +static int tests_failed; +static int tests_skipped; + +static void set_tpidr2(uint64_t val) +{ + asm volatile ( + "msr " SYS_TPIDR2 ", %0\n" + : + : "r"(val) + : "cc"); +} + +static uint64_t get_tpidr2(void) +{ + uint64_t val; + + asm volatile ( + "mrs %0, " SYS_TPIDR2 "\n" + : "=r"(val) + : + : "cc"); + + return val; +} + +static void print_summary(void) +{ + if (tests_passed + tests_failed + tests_skipped != EXPECTED_TESTS) + putstr("# UNEXPECTED TEST COUNT: "); + + putstr("# Totals: pass:"); + putnum(tests_passed); + putstr(" fail:"); + putnum(tests_failed); + putstr(" xfail:0 xpass:0 skip:"); + putnum(tests_skipped); + putstr(" error:0\n"); +} + +/* Processes should start with TPIDR2 == 0 */ +static int default_value(void) +{ + return get_tpidr2() == 0; +} + +/* If we set TPIDR2 we should read that value */ +static int write_read(void) +{ + set_tpidr2(getpid()); + + return getpid() == get_tpidr2(); +} + +/* If we set a value we should read the same value after scheduling out */ +static int write_sleep_read(void) +{ + set_tpidr2(getpid()); + + msleep(100); + + return getpid() == get_tpidr2(); +} + +/* + * If we fork the value in the parent should be unchanged and the + * child should start with the same value and be able to set its own + * value. + */ +static int write_fork_read(void) +{ + pid_t newpid, waiting, oldpid; + int status; + + set_tpidr2(getpid()); + + oldpid = getpid(); + newpid = fork(); + if (newpid == 0) { + /* In child */ + if (get_tpidr2() != oldpid) { + putstr("# TPIDR2 changed in child: "); + putnum(get_tpidr2()); + putstr("\n"); + exit(0); + } + + set_tpidr2(getpid()); + if (get_tpidr2() == getpid()) { + exit(1); + } else { + putstr("# Failed to set TPIDR2 in child\n"); + exit(0); + } + } + if (newpid < 0) { + putstr("# fork() failed: -"); + putnum(-newpid); + putstr("\n"); + return 0; + } + + for (;;) { + waiting = waitpid(newpid, &status, 0); + + if (waiting < 0) { + if (errno == EINTR) + continue; + putstr("# waitpid() failed: "); + putnum(errno); + putstr("\n"); + return 0; + } + if (waiting != newpid) { + putstr("# waitpid() returned wrong PID\n"); + return 0; + } + + if (!WIFEXITED(status)) { + putstr("# child did not exit\n"); + return 0; + } + + if (getpid() != get_tpidr2()) { + putstr("# TPIDR2 corrupted in parent\n"); + return 0; + } + + return WEXITSTATUS(status); + } +} + +/* + * sys_clone() has a lot of per architecture variation so just define + * it here rather than adding it to nolibc, plus the raw API is a + * little more convenient for this test. + */ +static int sys_clone(unsigned long clone_flags, unsigned long newsp, + int *parent_tidptr, unsigned long tls, + int *child_tidptr) +{ + return my_syscall5(__NR_clone, clone_flags, newsp, parent_tidptr, tls, + child_tidptr); +} + +/* + * If we clone with CLONE_SETTLS then the value in the parent should + * be unchanged and the child should start with zero and be able to + * set its own value. + */ +static int write_clone_read(void) +{ + int parent_tid, child_tid; + pid_t parent, waiting; + int ret, status; + + parent = getpid(); + set_tpidr2(parent); + + ret = sys_clone(CLONE_SETTLS, 0, &parent_tid, 0, &child_tid); + if (ret == -1) { + putstr("# clone() failed\n"); + putnum(errno); + putstr("\n"); + return 0; + } + + if (ret == 0) { + /* In child */ + if (get_tpidr2() != 0) { + putstr("# TPIDR2 non-zero in child: "); + putnum(get_tpidr2()); + putstr("\n"); + exit(0); + } + + if (gettid() == 0) + putstr("# Child TID==0\n"); + set_tpidr2(gettid()); + if (get_tpidr2() == gettid()) { + exit(1); + } else { + putstr("# Failed to set TPIDR2 in child\n"); + exit(0); + } + } + + for (;;) { + waiting = wait4(ret, &status, __WCLONE, NULL); + + if (waiting < 0) { + if (errno == EINTR) + continue; + putstr("# wait4() failed: "); + putnum(errno); + putstr("\n"); + return 0; + } + if (waiting != ret) { + putstr("# wait4() returned wrong PID "); + putnum(waiting); + putstr("\n"); + return 0; + } + + if (!WIFEXITED(status)) { + putstr("# child did not exit\n"); + return 0; + } + + if (parent != get_tpidr2()) { + putstr("# TPIDR2 corrupted in parent\n"); + return 0; + } + + return WEXITSTATUS(status); + } +} + +#define run_test(name) \ + if (name()) { \ + tests_passed++; \ + } else { \ + tests_failed++; \ + putstr("not "); \ + } \ + putstr("ok "); \ + putnum(++tests_run); \ + putstr(" " #name "\n"); + +int main(int argc, char **argv) +{ + int ret, i; + + putstr("TAP version 13\n"); + putstr("1.."); + putnum(EXPECTED_TESTS); + putstr("\n"); + + putstr("# PID: "); + putnum(getpid()); + putstr("\n"); + + /* + * This test is run with nolibc which doesn't support hwcap and + * it's probably disproportionate to implement so instead check + * for the default vector length configuration in /proc. + */ + ret = open("/proc/sys/abi/sme_default_vector_length", O_RDONLY, 0); + if (ret >= 0) { + run_test(default_value); + run_test(write_read); + run_test(write_sleep_read); + run_test(write_fork_read); + run_test(write_clone_read); + + } else { + putstr("# SME support not present\n"); + + for (i = 0; i < EXPECTED_TESTS; i++) { + putstr("ok "); + putnum(i); + putstr(" skipped, TPIDR2 not supported\n"); + } + + tests_skipped += EXPECTED_TESTS; + } + + print_summary(); + + return 0; +}