Add selftests to cbo.c to verify Zicbop extension behavior, and split the previous `--sigill` mode into two options so they can be tested independently.
The test checks: - That hwprobe correctly reports Zicbop presence and block size. - That prefetch instructions execute without exception on valid and NULL addresses when Zicbop is present.
Signed-off-by: Yao Zihong zihong.plct@isrc.iscas.ac.cn --- tools/testing/selftests/riscv/hwprobe/cbo.c | 168 ++++++++++++++++---- 1 file changed, 139 insertions(+), 29 deletions(-)
diff --git a/tools/testing/selftests/riscv/hwprobe/cbo.c b/tools/testing/selftests/riscv/hwprobe/cbo.c index 5e96ef785d0d..281ab440e696 100644 --- a/tools/testing/selftests/riscv/hwprobe/cbo.c +++ b/tools/testing/selftests/riscv/hwprobe/cbo.c @@ -15,24 +15,31 @@ #include <linux/compiler.h> #include <linux/kernel.h> #include <asm/ucontext.h> +#include <getopt.h>
#include "hwprobe.h" #include "../../kselftest.h"
#define MK_CBO(fn) le32_bswap((uint32_t)(fn) << 20 | 10 << 15 | 2 << 12 | 0 << 7 | 15) +#define MK_PREFETCH(fn) \ + le32_bswap(0 << 25 | (uint32_t)(fn) << 20 | 10 << 15 | 6 << 12 | 0 << 7 | 19)
static char mem[4096] __aligned(4096) = { [0 ... 4095] = 0xa5 };
-static bool illegal_insn; +static bool got_fault;
-static void sigill_handler(int sig, siginfo_t *info, void *context) +static void fault_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 == MK_CBO(regs[11])); + if (sig == SIGILL) + assert(insn == MK_CBO(regs[11]));
- illegal_insn = true; + if (sig == SIGSEGV || sig == SIGBUS) + assert(insn == MK_PREFETCH(regs[11])); + + got_fault = true; regs[0] += 4; }
@@ -45,39 +52,51 @@ static void sigill_handler(int sig, siginfo_t *info, void *context) : : "r" (base), "i" (fn), "i" (MK_CBO(fn)) : "a0", "a1", "memory"); \ })
+#define prefetch_insn(base, fn) \ +({ \ + asm volatile( \ + "mv a0, %0\n" \ + "li a1, %1\n" \ + ".4byte %2\n" \ + : : "r" (base), "i" (fn), "i" (MK_PREFETCH(fn)) : "a0", "a1"); \ +}) + static void cbo_inval(char *base) { cbo_insn(base, 0); } static void cbo_clean(char *base) { cbo_insn(base, 1); } static void cbo_flush(char *base) { cbo_insn(base, 2); } static void cbo_zero(char *base) { cbo_insn(base, 4); } +static void prefetch_i(char *base) { prefetch_insn(base, 0); } +static void prefetch_r(char *base) { prefetch_insn(base, 1); } +static void prefetch_w(char *base) { prefetch_insn(base, 3); }
static void test_no_cbo_inval(void *arg) { ksft_print_msg("Testing cbo.inval instruction remain privileged\n"); - illegal_insn = false; + got_fault = false; cbo_inval(&mem[0]); - ksft_test_result(illegal_insn, "No cbo.inval\n"); + ksft_test_result(got_fault, "No cbo.inval\n"); }
static void test_no_zicbom(void *arg) { ksft_print_msg("Testing Zicbom instructions remain privileged\n");
- illegal_insn = false; + got_fault = false; cbo_clean(&mem[0]); - ksft_test_result(illegal_insn, "No cbo.clean\n"); + ksft_test_result(got_fault, "No cbo.clean\n");
- illegal_insn = false; + got_fault = false; cbo_flush(&mem[0]); - ksft_test_result(illegal_insn, "No cbo.flush\n"); + ksft_test_result(got_fault, "No cbo.flush\n"); }
static void test_no_zicboz(void *arg) { ksft_print_msg("No Zicboz, testing cbo.zero remains privileged\n");
- illegal_insn = false; + got_fault = false; cbo_zero(&mem[0]); - ksft_test_result(illegal_insn, "No cbo.zero\n"); + ksft_test_result(got_fault, "No cbo.zero\n"); }
static bool is_power_of_2(__u64 n) @@ -85,6 +104,54 @@ static bool is_power_of_2(__u64 n) return n != 0 && (n & (n - 1)) == 0; }
+static void test_zicbop(void *arg) +{ + struct riscv_hwprobe pair = { + .key = RISCV_HWPROBE_KEY_ZICBOP_BLOCK_SIZE, + }; + + struct sigaction act = { + .sa_sigaction = &fault_handler, + .sa_flags = SA_SIGINFO + }; + + struct sigaction dfl = { + .sa_handler = SIG_DFL + }; + + cpu_set_t *cpus = (cpu_set_t *)arg; + __u64 block_size; + long rc; + + rc = sigaction(SIGSEGV, &act, NULL); + assert(rc == 0); + rc = sigaction(SIGBUS, &act, NULL); + assert(rc == 0); + + rc = riscv_hwprobe(&pair, 1, sizeof(cpu_set_t), (unsigned long *)cpus, 0); + block_size = pair.value; + ksft_test_result(rc == 0 && pair.key == RISCV_HWPROBE_KEY_ZICBOP_BLOCK_SIZE && + is_power_of_2(block_size), "Zicbop block size\n"); + ksft_print_msg("Zicbop block size: %llu\n", block_size); + + got_fault = false; + prefetch_i(&mem[0]); + prefetch_r(&mem[0]); + prefetch_w(&mem[0]); + ksft_test_result(!got_fault, "Zicbop prefetch.* on valid address\n"); + + got_fault = false; + prefetch_i(NULL); + prefetch_r(NULL); + prefetch_w(NULL); + ksft_test_result(!got_fault, "Zicbop prefetch.* on NULL\n"); + + rc = sigaction(SIGBUS, &dfl, NULL); + assert(rc == 0); + rc = sigaction(SIGSEGV, &dfl, NULL); + assert(rc == 0); +} + static void test_zicbom(void *arg) { struct riscv_hwprobe pair = { @@ -100,13 +167,13 @@ static void test_zicbom(void *arg) is_power_of_2(block_size), "Zicbom block size\n"); ksft_print_msg("Zicbom block size: %llu\n", block_size);
- illegal_insn = false; + got_fault = false; cbo_clean(&mem[block_size]); - ksft_test_result(!illegal_insn, "cbo.clean\n"); + ksft_test_result(!got_fault, "cbo.clean\n");
- illegal_insn = false; + got_fault = false; cbo_flush(&mem[block_size]); - ksft_test_result(!illegal_insn, "cbo.flush\n"); + ksft_test_result(!got_fault, "cbo.flush\n"); }
static void test_zicboz(void *arg) @@ -125,11 +192,11 @@ static void test_zicboz(void *arg) is_power_of_2(block_size), "Zicboz block size\n"); ksft_print_msg("Zicboz block size: %llu\n", block_size);
- illegal_insn = false; + got_fault = false; cbo_zero(&mem[block_size]); - ksft_test_result(!illegal_insn, "cbo.zero\n"); + ksft_test_result(!got_fault, "cbo.zero\n");
- if (illegal_insn || !is_power_of_2(block_size)) { + if (got_fault || !is_power_of_2(block_size)) { ksft_test_result_skip("cbo.zero check\n"); return; } @@ -177,7 +244,19 @@ static void check_no_zicbo_cpus(cpu_set_t *cpus, __u64 cbo) rc = riscv_hwprobe(&pair, 1, sizeof(cpu_set_t), (unsigned long *)&one_cpu, 0); assert(rc == 0 && pair.key == RISCV_HWPROBE_KEY_IMA_EXT_0);
- cbostr = cbo == RISCV_HWPROBE_EXT_ZICBOZ ? "Zicboz" : "Zicbom"; + switch (cbo) { + case RISCV_HWPROBE_EXT_ZICBOZ: + cbostr = "Zicboz"; + break; + case RISCV_HWPROBE_EXT_ZICBOM: + cbostr = "Zicbom"; + break; + case RISCV_HWPROBE_EXT_ZICBOP: + cbostr = "Zicbop"; + break; + default: + ksft_exit_fail_msg("Internal error: invalid cbo %llu\n", cbo); + }
if (pair.value & cbo) ksft_exit_fail_msg("%s is only present on a subset of harts.\n" @@ -194,6 +273,7 @@ enum { TEST_ZICBOM, TEST_NO_ZICBOM, TEST_NO_CBO_INVAL, + TEST_ZICBOP };
static struct test_info { @@ -206,26 +286,51 @@ static struct test_info { [TEST_ZICBOM] = { .nr_tests = 3, test_zicbom }, [TEST_NO_ZICBOM] = { .nr_tests = 2, test_no_zicbom }, [TEST_NO_CBO_INVAL] = { .nr_tests = 1, test_no_cbo_inval }, + [TEST_ZICBOP] = { .nr_tests = 3, test_zicbop } +}; + +static const struct option long_opts[] = { + {"zicbom-raises-sigill", no_argument, 0, 'm'}, + {"zicboz-raises-sigill", no_argument, 0, 'z'}, + {0, 0, 0, 0} };
int main(int argc, char **argv) { struct sigaction act = { - .sa_sigaction = &sigill_handler, + .sa_sigaction = &fault_handler, .sa_flags = SA_SIGINFO, }; + struct riscv_hwprobe pair; unsigned int plan = 0; cpu_set_t cpus; long rc; - int i; - - if (argc > 1 && !strcmp(argv[1], "--sigill")) { - rc = sigaction(SIGILL, &act, NULL); - assert(rc == 0); - tests[TEST_NO_ZICBOZ].enabled = true; - tests[TEST_NO_ZICBOM].enabled = true; - tests[TEST_NO_CBO_INVAL].enabled = true; + int i, opt, long_index; + + long_index = 0; + + while ((opt = getopt_long(argc, argv, "mz", long_opts, &long_index)) != -1) { + switch (opt) { + case 'm': + tests[TEST_NO_ZICBOM].enabled = true; + tests[TEST_NO_CBO_INVAL].enabled = true; + rc = sigaction(SIGILL, &act, NULL); + assert(rc == 0); + break; + case 'z': + tests[TEST_NO_ZICBOZ].enabled = true; + rc = sigaction(SIGILL, &act, NULL); + assert(rc == 0); + break; + case '?': + fprintf(stderr, + "Usage: %s [--zicbom-raises-sigill|-m] [--zicboz-raises-sigill|-z]\n", + argv[0]); + exit(1); + default: + break; + } }
rc = sched_getaffinity(0, sizeof(cpu_set_t), &cpus); @@ -253,6 +358,11 @@ int main(int argc, char **argv) check_no_zicbo_cpus(&cpus, RISCV_HWPROBE_EXT_ZICBOM); }
+ if (pair.value & RISCV_HWPROBE_EXT_ZICBOP) + tests[TEST_ZICBOP].enabled = true; + else + check_no_zicbo_cpus(&cpus, RISCV_HWPROBE_EXT_ZICBOP); + for (i = 0; i < ARRAY_SIZE(tests); ++i) plan += tests[i].enabled ? tests[i].nr_tests : 0;