--- /dev/null
+// SPDX-License-Identifier: GPL-2.0+
+
+/*
+ * Copyright 2018 IBM Corporation.
+ */
+
+#define __SANE_USERSPACE_TYPES__
+
+#include <sys/types.h>
+#include <stdint.h>
+#include <malloc.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include "utils.h"
+
+#define CACHELINE_SIZE 128
+
+struct perf_event_read {
+ __u64 nr;
+ __u64 l1d_misses;
+};
+
+static inline __u64 load(void *addr)
+{
+ __u64 tmp;
+
+ asm volatile("ld %0,0(%1)" : "=r"(tmp) : "b"(addr));
+
+ return tmp;
+}
+
+static void syscall_loop(char *p, unsigned long iterations,
+ unsigned long zero_size)
+{
+ for (unsigned long i = 0; i < iterations; i++) {
+ for (unsigned long j = 0; j < zero_size; j += CACHELINE_SIZE)
+ load(p + j);
+ getppid();
+ }
+}
+
+int rfi_flush_test(void)
+{
+ char *p;
+ int repetitions = 10;
+ int fd, passes = 0, iter, rc = 0;
+ struct perf_event_read v;
+ __u64 l1d_misses_total = 0;
+ unsigned long iterations = 100000, zero_size = 24 * 1024;
+ int rfi_flush_org, rfi_flush;
+
+ SKIP_IF(geteuid() != 0);
+
+ if (read_debugfs_file("powerpc/rfi_flush", &rfi_flush_org)) {
+ perror("Unable to read powerpc/rfi_flush debugfs file");
+ SKIP_IF(1);
+ }
+
+ rfi_flush = rfi_flush_org;
+
+ fd = perf_event_open_counter(PERF_TYPE_RAW, /* L1d miss */ 0x400f0, -1);
+ FAIL_IF(fd < 0);
+
+ p = (char *)memalign(zero_size, CACHELINE_SIZE);
+
+ FAIL_IF(perf_event_enable(fd));
+
+ set_dscr(1);
+
+ iter = repetitions;
+
+again:
+ FAIL_IF(perf_event_reset(fd));
+
+ syscall_loop(p, iterations, zero_size);
+
+ FAIL_IF(read(fd, &v, sizeof(v)) != sizeof(v));
+
+ /* Expect at least zero_size/CACHELINE_SIZE misses per iteration */
+ if (v.l1d_misses >= (iterations * zero_size / CACHELINE_SIZE) && rfi_flush)
+ passes++;
+ else if (v.l1d_misses < iterations && !rfi_flush)
+ passes++;
+
+ l1d_misses_total += v.l1d_misses;
+
+ while (--iter)
+ goto again;
+
+ if (passes < repetitions) {
+ printf("FAIL (L1D misses with rfi_flush=%d: %llu %c %lu) [%d/%d failures]\n",
+ rfi_flush, l1d_misses_total, rfi_flush ? '<' : '>',
+ rfi_flush ? (repetitions * iterations * zero_size / CACHELINE_SIZE) : iterations,
+ repetitions - passes, repetitions);
+ rc = 1;
+ } else
+ printf("PASS (L1D misses with rfi_flush=%d: %llu %c %lu) [%d/%d pass]\n",
+ rfi_flush, l1d_misses_total, rfi_flush ? '>' : '<',
+ rfi_flush ? (repetitions * iterations * zero_size / CACHELINE_SIZE) : iterations,
+ passes, repetitions);
+
+ if (rfi_flush == rfi_flush_org) {
+ rfi_flush = !rfi_flush_org;
+ if (write_debugfs_file("powerpc/rfi_flush", rfi_flush) < 0) {
+ perror("error writing to powerpc/rfi_flush debugfs file");
+ return 1;
+ }
+ iter = repetitions;
+ l1d_misses_total = 0;
+ passes = 0;
+ goto again;
+ }
+
+ perf_event_disable(fd);
+ close(fd);
+
+ set_dscr(0);
+
+ if (write_debugfs_file("powerpc/rfi_flush", rfi_flush_org) < 0) {
+ perror("unable to restore original value of powerpc/rfi_flush debugfs file");
+ return 1;
+ }
+
+ return rc;
+}
+
+int main(int argc, char *argv[])
+{
+ return test_harness(rfi_flush_test, "rfi_flush_test");
+}
#include <fcntl.h>
#include <link.h>
#include <sched.h>
+#include <signal.h>
#include <stdio.h>
+#include <stdlib.h>
#include <string.h>
+#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/utsname.h>
#include <unistd.h>
+#include <asm/unistd.h>
+#include <linux/limits.h>
#include "utils.h"
static char auxv[4096];
+extern unsigned int dscr_insn[];
int read_auxv(char *buf, ssize_t buf_size)
{
return strcmp(uts.machine, "ppc64le") == 0;
}
+
+int read_debugfs_file(char *debugfs_file, int *result)
+{
+ int rc = -1, fd;
+ char path[PATH_MAX];
+ char value[16];
+
+ strcpy(path, "/sys/kernel/debug/");
+ strncat(path, debugfs_file, PATH_MAX - strlen(path) - 1);
+
+ if ((fd = open(path, O_RDONLY)) < 0)
+ return rc;
+
+ if ((rc = read(fd, value, sizeof(value))) < 0)
+ return rc;
+
+ value[15] = 0;
+ *result = atoi(value);
+ close(fd);
+
+ return 0;
+}
+
+int write_debugfs_file(char *debugfs_file, int result)
+{
+ int rc = -1, fd;
+ char path[PATH_MAX];
+ char value[16];
+
+ strcpy(path, "/sys/kernel/debug/");
+ strncat(path, debugfs_file, PATH_MAX - strlen(path) - 1);
+
+ if ((fd = open(path, O_WRONLY)) < 0)
+ return rc;
+
+ snprintf(value, 16, "%d", result);
+
+ if ((rc = write(fd, value, strlen(value))) < 0)
+ return rc;
+
+ close(fd);
+
+ return 0;
+}
+
+static long perf_event_open(struct perf_event_attr *hw_event, pid_t pid,
+ int cpu, int group_fd, unsigned long flags)
+{
+ return syscall(__NR_perf_event_open, hw_event, pid, cpu,
+ group_fd, flags);
+}
+
+static void perf_event_attr_init(struct perf_event_attr *event_attr,
+ unsigned int type,
+ unsigned long config)
+{
+ memset(event_attr, 0, sizeof(*event_attr));
+
+ event_attr->type = type;
+ event_attr->size = sizeof(struct perf_event_attr);
+ event_attr->config = config;
+ event_attr->read_format = PERF_FORMAT_GROUP;
+ event_attr->disabled = 1;
+ event_attr->exclude_kernel = 1;
+ event_attr->exclude_hv = 1;
+ event_attr->exclude_guest = 1;
+}
+
+int perf_event_open_counter(unsigned int type,
+ unsigned long config, int group_fd)
+{
+ int fd;
+ struct perf_event_attr event_attr;
+
+ perf_event_attr_init(&event_attr, type, config);
+
+ fd = perf_event_open(&event_attr, 0, -1, group_fd, 0);
+
+ if (fd < 0)
+ perror("perf_event_open() failed");
+
+ return fd;
+}
+
+int perf_event_enable(int fd)
+{
+ if (ioctl(fd, PERF_EVENT_IOC_ENABLE, PERF_IOC_FLAG_GROUP) == -1) {
+ perror("error while enabling perf events");
+ return -1;
+ }
+
+ return 0;
+}
+
+int perf_event_disable(int fd)
+{
+ if (ioctl(fd, PERF_EVENT_IOC_DISABLE, PERF_IOC_FLAG_GROUP) == -1) {
+ perror("error disabling perf events");
+ return -1;
+ }
+
+ return 0;
+}
+
+int perf_event_reset(int fd)
+{
+ if (ioctl(fd, PERF_EVENT_IOC_RESET, PERF_IOC_FLAG_GROUP) == -1) {
+ perror("error resetting perf events");
+ return -1;
+ }
+
+ return 0;
+}
+
+static void sigill_handler(int signr, siginfo_t *info, void *unused)
+{
+ static int warned = 0;
+ ucontext_t *ctx = (ucontext_t *)unused;
+ unsigned long *pc = &UCONTEXT_NIA(ctx);
+
+ if (*pc == (unsigned long)&dscr_insn) {
+ if (!warned++)
+ printf("WARNING: Skipping over dscr setup. Consider running 'ppc64_cpu --dscr=1' manually.\n");
+ *pc += 4;
+ } else {
+ printf("SIGILL at %p\n", pc);
+ abort();
+ }
+}
+
+void set_dscr(unsigned long val)
+{
+ static int init = 0;
+ struct sigaction sa;
+
+ if (!init) {
+ memset(&sa, 0, sizeof(sa));
+ sa.sa_sigaction = sigill_handler;
+ sa.sa_flags = SA_SIGINFO;
+ if (sigaction(SIGILL, &sa, NULL))
+ perror("sigill_handler");
+ init = 1;
+ }
+
+ asm volatile("dscr_insn: mtspr %1,%0" : : "r" (val), "i" (SPRN_DSCR));
+}
projects / users / hch / misc.git / commitdiff