[PATCH v17 4/9] tools/counter: Create Counter tools
William Breathitt Gray
vilhelm.gray at gmail.com
Tue Sep 28 20:16:01 PDT 2021
This creates an example Counter program under tools/counter/*
to exemplify the Counter character device interface.
Cc: Pavel Machek <pavel at ucw.cz>
Signed-off-by: William Breathitt Gray <vilhelm.gray at gmail.com>
---
MAINTAINERS | 1 +
tools/Makefile | 13 ++---
tools/counter/Build | 1 +
tools/counter/Makefile | 53 +++++++++++++++++++
tools/counter/counter_example.c | 92 +++++++++++++++++++++++++++++++++
5 files changed, 154 insertions(+), 6 deletions(-)
create mode 100644 tools/counter/Build
create mode 100644 tools/counter/Makefile
create mode 100644 tools/counter/counter_example.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 3c95ada1b830..71082000046b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4821,6 +4821,7 @@ F: Documentation/driver-api/generic-counter.rst
F: drivers/counter/
F: include/linux/counter.h
F: include/uapi/linux/counter.h
+F: tools/counter/
CP2615 I2C DRIVER
M: Bence Csókás <bence98 at sch.bme.hu>
diff --git a/tools/Makefile b/tools/Makefile
index 7e9d34ddd74c..5da1fde03a9a 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -12,6 +12,7 @@ help:
@echo ' acpi - ACPI tools'
@echo ' bpf - misc BPF tools'
@echo ' cgroup - cgroup tools'
+ @echo ' counter - counter tools'
@echo ' cpupower - a tool for all things x86 CPU power'
@echo ' debugging - tools for debugging'
@echo ' firewire - the userspace part of nosy, an IEEE-1394 traffic sniffer'
@@ -65,7 +66,7 @@ acpi: FORCE
cpupower: FORCE
$(call descend,power/$@)
-cgroup firewire hv guest bootconfig spi usb virtio vm bpf iio gpio objtool leds wmi pci firmware debugging tracing: FORCE
+cgroup counter firewire hv guest bootconfig spi usb virtio vm bpf iio gpio objtool leds wmi pci firmware debugging tracing: FORCE
$(call descend,$@)
bpf/%: FORCE
@@ -100,7 +101,7 @@ freefall: FORCE
kvm_stat: FORCE
$(call descend,kvm/$@)
-all: acpi cgroup cpupower gpio hv firewire liblockdep \
+all: acpi cgroup counter cpupower gpio hv firewire liblockdep \
perf selftests bootconfig spi turbostat usb \
virtio vm bpf x86_energy_perf_policy \
tmon freefall iio objtool kvm_stat wmi \
@@ -112,7 +113,7 @@ acpi_install:
cpupower_install:
$(call descend,power/$(@:_install=),install)
-cgroup_install firewire_install gpio_install hv_install iio_install perf_install bootconfig_install spi_install usb_install virtio_install vm_install bpf_install objtool_install wmi_install pci_install debugging_install tracing_install:
+cgroup_install counter_install firewire_install gpio_install hv_install iio_install perf_install bootconfig_install spi_install usb_install virtio_install vm_install bpf_install objtool_install wmi_install pci_install debugging_install tracing_install:
$(call descend,$(@:_install=),install)
liblockdep_install:
@@ -133,7 +134,7 @@ freefall_install:
kvm_stat_install:
$(call descend,kvm/$(@:_install=),install)
-install: acpi_install cgroup_install cpupower_install gpio_install \
+install: acpi_install cgroup_install counter_install cpupower_install gpio_install \
hv_install firewire_install iio_install liblockdep_install \
perf_install selftests_install turbostat_install usb_install \
virtio_install vm_install bpf_install x86_energy_perf_policy_install \
@@ -147,7 +148,7 @@ acpi_clean:
cpupower_clean:
$(call descend,power/cpupower,clean)
-cgroup_clean hv_clean firewire_clean bootconfig_clean spi_clean usb_clean virtio_clean vm_clean wmi_clean bpf_clean iio_clean gpio_clean objtool_clean leds_clean pci_clean firmware_clean debugging_clean tracing_clean:
+cgroup_clean counter_clean hv_clean firewire_clean bootconfig_clean spi_clean usb_clean virtio_clean vm_clean wmi_clean bpf_clean iio_clean gpio_clean objtool_clean leds_clean pci_clean firmware_clean debugging_clean tracing_clean:
$(call descend,$(@:_clean=),clean)
liblockdep_clean:
@@ -181,7 +182,7 @@ freefall_clean:
build_clean:
$(call descend,build,clean)
-clean: acpi_clean cgroup_clean cpupower_clean hv_clean firewire_clean \
+clean: acpi_clean cgroup_clean counter_clean cpupower_clean hv_clean firewire_clean \
perf_clean selftests_clean turbostat_clean bootconfig_clean spi_clean usb_clean virtio_clean \
vm_clean bpf_clean iio_clean x86_energy_perf_policy_clean tmon_clean \
freefall_clean build_clean libbpf_clean libsubcmd_clean liblockdep_clean \
diff --git a/tools/counter/Build b/tools/counter/Build
new file mode 100644
index 000000000000..33f4a51d715e
--- /dev/null
+++ b/tools/counter/Build
@@ -0,0 +1 @@
+counter_example-y += counter_example.o
diff --git a/tools/counter/Makefile b/tools/counter/Makefile
new file mode 100644
index 000000000000..5ebc195fd9c0
--- /dev/null
+++ b/tools/counter/Makefile
@@ -0,0 +1,53 @@
+# SPDX-License-Identifier: GPL-2.0
+include ../scripts/Makefile.include
+
+bindir ?= /usr/bin
+
+ifeq ($(srctree),)
+srctree := $(patsubst %/,%,$(dir $(CURDIR)))
+srctree := $(patsubst %/,%,$(dir $(srctree)))
+endif
+
+# Do not use make's built-in rules
+# (this improves performance and avoids hard-to-debug behaviour);
+MAKEFLAGS += -r
+
+override CFLAGS += -O2 -Wall -g -D_GNU_SOURCE -I$(OUTPUT)include
+
+ALL_TARGETS := counter_example
+ALL_PROGRAMS := $(patsubst %,$(OUTPUT)%,$(ALL_TARGETS))
+
+all: $(ALL_PROGRAMS)
+
+export srctree OUTPUT CC LD CFLAGS
+include $(srctree)/tools/build/Makefile.include
+
+#
+# We need the following to be outside of kernel tree
+#
+$(OUTPUT)include/linux/counter.h: ../../include/uapi/linux/counter.h
+ mkdir -p $(OUTPUT)include/linux 2>&1 || true
+ ln -sf $(CURDIR)/../../include/uapi/linux/counter.h $@
+
+prepare: $(OUTPUT)include/linux/counter.h
+
+COUNTER_EXAMPLE := $(OUTPUT)counter_example.o
+$(COUNTER_EXAMPLE): prepare FORCE
+ $(Q)$(MAKE) $(build)=counter_example
+$(OUTPUT)counter_example: $(COUNTER_EXAMPLE)
+ $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $< -o $@
+
+clean:
+ rm -f $(ALL_PROGRAMS)
+ rm -rf $(OUTPUT)include/linux/counter.h
+ find $(if $(OUTPUT),$(OUTPUT),.) -name '*.o' -delete -o -name '\.*.d' -delete
+
+install: $(ALL_PROGRAMS)
+ install -d -m 755 $(DESTDIR)$(bindir); \
+ for program in $(ALL_PROGRAMS); do \
+ install $$program $(DESTDIR)$(bindir); \
+ done
+
+FORCE:
+
+.PHONY: all install clean FORCE prepare
diff --git a/tools/counter/counter_example.c b/tools/counter/counter_example.c
new file mode 100644
index 000000000000..be55287b950f
--- /dev/null
+++ b/tools/counter/counter_example.c
@@ -0,0 +1,92 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Counter - example userspace application
+ *
+ * The userspace application opens /dev/counter0, configures the
+ * COUNTER_EVENT_INDEX event channel 0 to gather Count 0 count and Count
+ * 1 count, and prints out the data as it becomes available on the
+ * character device node.
+ *
+ * Copyright (C) 2021 William Breathitt Gray
+ */
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/counter.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+
+static struct counter_watch watches[2] = {
+ {
+ /* Component data: Count 0 count */
+ .component.type = COUNTER_COMPONENT_COUNT,
+ .component.scope = COUNTER_SCOPE_COUNT,
+ .component.parent = 0,
+ /* Event type: Index */
+ .event = COUNTER_EVENT_INDEX,
+ /* Device event channel 0 */
+ .channel = 0,
+ },
+ {
+ /* Component data: Count 1 count */
+ .component.type = COUNTER_COMPONENT_COUNT,
+ .component.scope = COUNTER_SCOPE_COUNT,
+ .component.parent = 1,
+ /* Event type: Index */
+ .event = COUNTER_EVENT_INDEX,
+ /* Device event channel 0 */
+ .channel = 0,
+ },
+};
+
+int main(void)
+{
+ int fd;
+ int ret;
+ int i;
+ struct counter_event event_data[2];
+
+ fd = open("/dev/counter0", O_RDWR);
+ if (fd == -1) {
+ perror("Unable to open /dev/counter0");
+ return 1;
+ }
+
+ for (i = 0; i < 2; i++) {
+ ret = ioctl(fd, COUNTER_ADD_WATCH_IOCTL, watches + i);
+ if (ret == -1) {
+ fprintf(stderr, "Error adding watches[%d]: %s\n", i,
+ strerror(errno));
+ return 1;
+ }
+ }
+ ret = ioctl(fd, COUNTER_ENABLE_EVENTS_IOCTL);
+ if (ret == -1) {
+ perror("Error enabling events");
+ return 1;
+ }
+
+ for (;;) {
+ ret = read(fd, event_data, sizeof(event_data));
+ if (ret == -1) {
+ perror("Failed to read event data");
+ return 1;
+ }
+
+ if (ret != sizeof(event_data)) {
+ fprintf(stderr, "Failed to read event data\n");
+ return -EIO;
+ }
+
+ printf("Timestamp 0: %llu\tCount 0: %llu\n"
+ "Error Message 0: %s\n"
+ "Timestamp 1: %llu\tCount 1: %llu\n"
+ "Error Message 1: %s\n",
+ event_data[0].timestamp, event_data[0].value,
+ strerror(event_data[0].status),
+ event_data[1].timestamp, event_data[1].value,
+ strerror(event_data[1].status));
+ }
+
+ return 0;
+}
--
2.33.0
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