[PATCH v2 9/9] perf: Remove x86 specific rdpmc test
From: Rob Herring
Date: Fri Aug 28 2020 - 16:56:52 EST
Now that we have a common libperf based userspace counter read test
with the same functionality as the x86 specific rdpmc test, let's remove
it.
Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
---
This one is optional. On the plus side, it eliminates a copy of the read
loop. The main downside I see is loosing the ability to test in 'perf test'.
tools/perf/arch/x86/include/arch-tests.h | 1 -
tools/perf/arch/x86/tests/Build | 1 -
tools/perf/arch/x86/tests/arch-tests.c | 4 -
tools/perf/arch/x86/tests/rdpmc.c | 182 -----------------------
4 files changed, 188 deletions(-)
delete mode 100644 tools/perf/arch/x86/tests/rdpmc.c
diff --git a/tools/perf/arch/x86/include/arch-tests.h b/tools/perf/arch/x86/include/arch-tests.h
index c41c5affe4be..d9c32ba0cdac 100644
--- a/tools/perf/arch/x86/include/arch-tests.h
+++ b/tools/perf/arch/x86/include/arch-tests.h
@@ -6,7 +6,6 @@
struct test;
/* Tests */
-int test__rdpmc(struct test *test __maybe_unused, int subtest);
int test__perf_time_to_tsc(struct test *test __maybe_unused, int subtest);
int test__insn_x86(struct test *test __maybe_unused, int subtest);
int test__intel_pt_pkt_decoder(struct test *test, int subtest);
diff --git a/tools/perf/arch/x86/tests/Build b/tools/perf/arch/x86/tests/Build
index 2997c506550c..e3b3cd3b40e8 100644
--- a/tools/perf/arch/x86/tests/Build
+++ b/tools/perf/arch/x86/tests/Build
@@ -2,7 +2,6 @@ perf-$(CONFIG_DWARF_UNWIND) += regs_load.o
perf-$(CONFIG_DWARF_UNWIND) += dwarf-unwind.o
perf-y += arch-tests.o
-perf-y += rdpmc.o
perf-y += perf-time-to-tsc.o
perf-$(CONFIG_AUXTRACE) += insn-x86.o intel-pt-pkt-decoder-test.o
perf-$(CONFIG_X86_64) += bp-modify.o
diff --git a/tools/perf/arch/x86/tests/arch-tests.c b/tools/perf/arch/x86/tests/arch-tests.c
index 6763135aec17..300e9954d530 100644
--- a/tools/perf/arch/x86/tests/arch-tests.c
+++ b/tools/perf/arch/x86/tests/arch-tests.c
@@ -4,10 +4,6 @@
#include "arch-tests.h"
struct test arch_tests[] = {
- {
- .desc = "x86 rdpmc",
- .func = test__rdpmc,
- },
{
.desc = "Convert perf time to TSC",
.func = test__perf_time_to_tsc,
diff --git a/tools/perf/arch/x86/tests/rdpmc.c b/tools/perf/arch/x86/tests/rdpmc.c
deleted file mode 100644
index 1ea916656a2d..000000000000
--- a/tools/perf/arch/x86/tests/rdpmc.c
+++ /dev/null
@@ -1,182 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-#include <errno.h>
-#include <unistd.h>
-#include <stdlib.h>
-#include <signal.h>
-#include <sys/mman.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <linux/string.h>
-#include <linux/types.h>
-#include "perf-sys.h"
-#include "debug.h"
-#include "tests/tests.h"
-#include "cloexec.h"
-#include "event.h"
-#include <internal/lib.h> // page_size
-#include "arch-tests.h"
-
-static u64 rdpmc(unsigned int counter)
-{
- unsigned int low, high;
-
- asm volatile("rdpmc" : "=a" (low), "=d" (high) : "c" (counter));
-
- return low | ((u64)high) << 32;
-}
-
-static u64 rdtsc(void)
-{
- unsigned int low, high;
-
- asm volatile("rdtsc" : "=a" (low), "=d" (high));
-
- return low | ((u64)high) << 32;
-}
-
-static u64 mmap_read_self(void *addr)
-{
- struct perf_event_mmap_page *pc = addr;
- u32 seq, idx, time_mult = 0, time_shift = 0;
- u64 count, cyc = 0, time_offset = 0, enabled, running, delta;
-
- do {
- seq = pc->lock;
- barrier();
-
- enabled = pc->time_enabled;
- running = pc->time_running;
-
- if (enabled != running) {
- cyc = rdtsc();
- time_mult = pc->time_mult;
- time_shift = pc->time_shift;
- time_offset = pc->time_offset;
- }
-
- idx = pc->index;
- count = pc->offset;
- if (idx)
- count += rdpmc(idx - 1);
-
- barrier();
- } while (pc->lock != seq);
-
- if (enabled != running) {
- u64 quot, rem;
-
- quot = (cyc >> time_shift);
- rem = cyc & (((u64)1 << time_shift) - 1);
- delta = time_offset + quot * time_mult +
- ((rem * time_mult) >> time_shift);
-
- enabled += delta;
- if (idx)
- running += delta;
-
- quot = count / running;
- rem = count % running;
- count = quot * enabled + (rem * enabled) / running;
- }
-
- return count;
-}
-
-/*
- * If the RDPMC instruction faults then signal this back to the test parent task:
- */
-static void segfault_handler(int sig __maybe_unused,
- siginfo_t *info __maybe_unused,
- void *uc __maybe_unused)
-{
- exit(-1);
-}
-
-static int __test__rdpmc(void)
-{
- volatile int tmp = 0;
- u64 i, loops = 1000;
- int n;
- int fd;
- void *addr;
- struct perf_event_attr attr = {
- .type = PERF_TYPE_HARDWARE,
- .config = PERF_COUNT_HW_INSTRUCTIONS,
- .exclude_kernel = 1,
- };
- u64 delta_sum = 0;
- struct sigaction sa;
- char sbuf[STRERR_BUFSIZE];
-
- sigfillset(&sa.sa_mask);
- sa.sa_sigaction = segfault_handler;
- sa.sa_flags = 0;
- sigaction(SIGSEGV, &sa, NULL);
-
- fd = sys_perf_event_open(&attr, 0, -1, -1,
- perf_event_open_cloexec_flag());
- if (fd < 0) {
- pr_err("Error: sys_perf_event_open() syscall returned "
- "with %d (%s)\n", fd,
- str_error_r(errno, sbuf, sizeof(sbuf)));
- return -1;
- }
-
- addr = mmap(NULL, page_size, PROT_READ, MAP_SHARED, fd, 0);
- if (addr == (void *)(-1)) {
- pr_err("Error: mmap() syscall returned with (%s)\n",
- str_error_r(errno, sbuf, sizeof(sbuf)));
- goto out_close;
- }
-
- for (n = 0; n < 6; n++) {
- u64 stamp, now, delta;
-
- stamp = mmap_read_self(addr);
-
- for (i = 0; i < loops; i++)
- tmp++;
-
- now = mmap_read_self(addr);
- loops *= 10;
-
- delta = now - stamp;
- pr_debug("%14d: %14Lu\n", n, (long long)delta);
-
- delta_sum += delta;
- }
-
- munmap(addr, page_size);
- pr_debug(" ");
-out_close:
- close(fd);
-
- if (!delta_sum)
- return -1;
-
- return 0;
-}
-
-int test__rdpmc(struct test *test __maybe_unused, int subtest __maybe_unused)
-{
- int status = 0;
- int wret = 0;
- int ret;
- int pid;
-
- pid = fork();
- if (pid < 0)
- return -1;
-
- if (!pid) {
- ret = __test__rdpmc();
-
- exit(ret);
- }
-
- wret = waitpid(pid, &status, 0);
- if (wret < 0 || status)
- return -1;
-
- return 0;
-}
--
2.25.1