This creates an example Counter program under tools/counter/* to exemplify the Counter character device interface.
Cc: Pavel Machek <pa...@ucw.cz> Signed-off-by: William Breathitt Gray <vilhelm.g...@gmail.com> --- MAINTAINERS | 1 + tools/Makefile | 13 ++--- tools/counter/Build | 1 + tools/counter/Makefile | 53 ++++++++++++++++++ tools/counter/counter_example.c | 95 +++++++++++++++++++++++++++++++++ 5 files changed, 157 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 93233a07f5aa..aa61b40d02fe 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -4582,6 +4582,7 @@ F: Documentation/driver-api/generic-counter.rst F: drivers/counter/ F: include/linux/counter.h F: include/uapi/linux/counter.h +F: tools/counter/ CPMAC ETHERNET DRIVER M: Florian Fainelli <f.faine...@gmail.com> diff --git a/tools/Makefile b/tools/Makefile index 7e9d34ddd74c..4c26400ffc03 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..71dfec673c11 --- /dev/null +++ b/tools/counter/counter_example.c @@ -0,0 +1,95 @@ +// 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> + +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; + struct counter_event event_data[2]; + + fd = open("/dev/counter0", O_RDWR); + if (fd == -1) { + perror("Unable to open /dev/counter0"); + return -errno; + } + + ret = ioctl(fd, COUNTER_ADD_WATCH_IOCTL, watches); + if (ret == -1) { + perror("Error adding watches[0]"); + return -errno; + } + ret = ioctl(fd, COUNTER_ADD_WATCH_IOCTL, watches + 1); + if (ret == -1) { + perror("Error adding watches[1]"); + return -errno; + } + ret = ioctl(fd, COUNTER_ENABLE_EVENTS_IOCTL); + if (ret == -1) { + perror("Error enabling events"); + return -errno; + } + + for (;;) { + ret = read(fd, event_data, sizeof(event_data)); + if (ret == -1) { + perror("Failed to read event data"); + return -errno; + } + + 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", + (unsigned long long)event_data[0].timestamp, + (unsigned long long)event_data[0].value, + strerror(event_data[0].status), + (unsigned long long)event_data[1].timestamp, + (unsigned long long)event_data[1].value, + strerror(event_data[1].status)); + } + + return 0; +} -- 2.30.1