[PATCH v2 9/9] perf: Remove x86 specific rdpmc test

[Rob Herring <robh@kernel.org>]

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@kernel.org>
---
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