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The makefile is borrowed from sched_ext tests. Signed-off-by: Pavel Begunkov --- tools/testing/selftests/Makefile | 3 +- tools/testing/selftests/io_uring/Makefile | 162 +++++++++++++++++++ tools/testing/selftests/io_uring/basic.bpf.c | 131 +++++++++++++++ tools/testing/selftests/io_uring/common.h | 6 + tools/testing/selftests/io_uring/runner.c | 107 ++++++++++++ 5 files changed, 408 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/io_uring/Makefile create mode 100644 tools/testing/selftests/io_uring/basic.bpf.c create mode 100644 tools/testing/selftests/io_uring/common.h create mode 100644 tools/testing/selftests/io_uring/runner.c diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index 56e44a98d6a5..5e965ba3697c 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -130,6 +130,7 @@ TARGETS += vfio TARGETS += x86 TARGETS += x86/bugs TARGETS += zram +TARGETS += io_uring #Please keep the TARGETS list alphabetically sorted # Run "make quicktest=1 run_tests" or # "make quicktest=1 kselftest" from top level Makefile @@ -147,7 +148,7 @@ endif # User can optionally provide a TARGETS skiplist. By default we skip # targets using BPF since it has cutting edge build time dependencies # which require more effort to install. -SKIP_TARGETS ?= bpf sched_ext +SKIP_TARGETS ?= bpf sched_ext io_uring ifneq ($(SKIP_TARGETS),) TMP := $(filter-out $(SKIP_TARGETS), $(TARGETS)) override TARGETS := $(TMP) diff --git a/tools/testing/selftests/io_uring/Makefile b/tools/testing/selftests/io_uring/Makefile new file mode 100644 index 000000000000..f3b9fb653973 --- /dev/null +++ b/tools/testing/selftests/io_uring/Makefile @@ -0,0 +1,162 @@ +# SPDX-License-Identifier: GPL-2.0 +include ../../../build/Build.include +include ../../../scripts/Makefile.arch +include ../../../scripts/Makefile.include + +TEST_GEN_PROGS := runner + +# override lib.mk's default rules +OVERRIDE_TARGETS := 1 +include ../lib.mk + +CURDIR := $(abspath .) +REPOROOT := $(abspath ../../../..) +TOOLSDIR := $(REPOROOT)/tools +LIBDIR := $(TOOLSDIR)/lib +BPFDIR := $(LIBDIR)/bpf +TOOLSINCDIR := $(TOOLSDIR)/include +BPFTOOLDIR := $(TOOLSDIR)/bpf/bpftool +APIDIR := $(TOOLSINCDIR)/uapi +GENDIR := $(REPOROOT)/include/generated +GENHDR := $(GENDIR)/autoconf.h + +OUTPUT_DIR := $(OUTPUT)/build +OBJ_DIR := $(OUTPUT_DIR)/obj +INCLUDE_DIR := $(OUTPUT_DIR)/include +BPFOBJ_DIR := $(OBJ_DIR)/libbpf +IOUOBJ_DIR := $(OBJ_DIR)/io_uring +LIBBPF_OUTPUT := $(OBJ_DIR)/libbpf/libbpf.a +BPFOBJ := $(BPFOBJ_DIR)/libbpf.a + +DEFAULT_BPFTOOL := $(OUTPUT_DIR)/host/sbin/bpftool +HOST_OBJ_DIR := $(OBJ_DIR)/host/bpftool +HOST_LIBBPF_OUTPUT := $(OBJ_DIR)/host/libbpf/ +HOST_LIBBPF_DESTDIR := $(OUTPUT_DIR)/host/ +HOST_DESTDIR := $(OUTPUT_DIR)/host/ + +VMLINUX_BTF_PATHS ?= $(if $(O),$(O)/vmlinux) \ + $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux) \ + ../../../../vmlinux \ + /sys/kernel/btf/vmlinux \ + /boot/vmlinux-$(shell uname -r) +VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS)))) +ifeq ($(VMLINUX_BTF),) +$(error Cannot find a vmlinux for VMLINUX_BTF at any of "$(VMLINUX_BTF_PATHS)") +endif + +BPFTOOL ?= $(DEFAULT_BPFTOOL) + +ifneq ($(wildcard $(GENHDR)),) + GENFLAGS := -DHAVE_GENHDR +endif + +CFLAGS += -g -O2 -rdynamic -pthread -Wall -Werror $(GENFLAGS) \ + -I$(INCLUDE_DIR) -I$(GENDIR) -I$(LIBDIR) \ + -I$(TOOLSINCDIR) -I$(APIDIR) -I$(CURDIR)/include + +# Silence some warnings when compiled with clang +ifneq ($(LLVM),) +CFLAGS += -Wno-unused-command-line-argument +endif + +LDFLAGS = -lelf -lz -lpthread -lzstd + +IS_LITTLE_ENDIAN = $(shell $(CC) -dM -E - &1 \ + | sed -n '/<...> search starts here:/,/End of search list./{ s| \(/.*\)|-idirafter \1|p }') \ +$(shell $(1) $(2) -dM -E - $@ +else + $(call msg,CP,,$@) + $(Q)cp "$(VMLINUX_H)" $@ +endif + +$(IOUOBJ_DIR)/%.bpf.o: %.bpf.c $(INCLUDE_DIR)/vmlinux.h | $(BPFOBJ) $(IOUOBJ_DIR) + $(call msg,CLNG-BPF,,$(notdir $@)) + $(Q)$(CLANG) $(BPF_CFLAGS) -target bpf -c $< -o $@ + +$(INCLUDE_DIR)/%.bpf.skel.h: $(IOUOBJ_DIR)/%.bpf.o $(INCLUDE_DIR)/vmlinux.h $(BPFTOOL) | $(INCLUDE_DIR) + $(eval sched=$(notdir $@)) + $(call msg,GEN-SKEL,,$(sched)) + $(Q)$(BPFTOOL) gen object $(<:.o=.linked1.o) $< + $(Q)$(BPFTOOL) gen object $(<:.o=.linked2.o) $(<:.o=.linked1.o) + $(Q)$(BPFTOOL) gen object $(<:.o=.linked3.o) $(<:.o=.linked2.o) + $(Q)diff $(<:.o=.linked2.o) $(<:.o=.linked3.o) + $(Q)$(BPFTOOL) gen skeleton $(<:.o=.linked3.o) name $(subst .bpf.skel.h,,$(sched)) > $@ + $(Q)$(BPFTOOL) gen subskeleton $(<:.o=.linked3.o) name $(subst .bpf.skel.h,,$(sched)) > $(@:.skel.h=.subskel.h) + +override define CLEAN + rm -rf $(OUTPUT_DIR) + rm -f $(TEST_GEN_PROGS) +endef + +all_test_bpfprogs := $(foreach prog,$(wildcard *.bpf.c),$(INCLUDE_DIR)/$(patsubst %.c,%.skel.h,$(prog))) + +$(IOUOBJ_DIR)/runner.o: runner.c $(all_test_bpfprogs) | $(IOUOBJ_DIR) $(BPFOBJ) + $(CC) $(CFLAGS) -c $< -o $@ + +$(OUTPUT)/runner: $(IOUOBJ_DIR)/runner.o $(BPFOBJ) + $(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS) + +.DEFAULT_GOAL := all + +.DELETE_ON_ERROR: + +.SECONDARY: diff --git a/tools/testing/selftests/io_uring/basic.bpf.c b/tools/testing/selftests/io_uring/basic.bpf.c new file mode 100644 index 000000000000..f1bccf3b5f42 --- /dev/null +++ b/tools/testing/selftests/io_uring/basic.bpf.c @@ -0,0 +1,131 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#include +#include +#include +#include +#include "vmlinux.h" +#include "common.h" + +char LICENSE[] SEC("license") = "Dual BSD/GPL"; + +#define REQ_TOKEN 0xabba1741 + +const unsigned max_inflight = 8; +const volatile unsigned cq_hdr_offset; +const volatile unsigned sq_hdr_offset; +const volatile unsigned cqes_offset; + +int reqs_to_run; +unsigned inflight; + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __uint(max_entries, 3); + __type(key, u32); + __type(value, s64); +} res_map SEC(".maps"); + +#define t_min(a, b) ((a) < (b) ? (a) : (b)) + +static inline void set_cq_wait(struct iou_loop_params *lp, + struct io_uring *cq_hdr, unsigned to_wait) +{ + lp->cq_wait_idx = cq_hdr->head + to_wait; +} + +static inline void write_result(int res) +{ + u32 key = SLOT_RES; + u64 *val; + + val = bpf_map_lookup_elem(&res_map, &key); + if (val) + *val = res; +} + +static inline void write_stats(int idx, unsigned int v) +{ + u32 key = idx; + u64 *val; + + val = bpf_map_lookup_elem(&res_map, &key); + if (val) + *val += v; +} + +SEC("struct_ops.s/link_loop") +int BPF_PROG(link_loop, struct io_ring_ctx *ring, struct iou_loop_params *ls) +{ + struct io_uring *sq_hdr, *cq_hdr; + struct io_uring_sqe *sqes; + struct io_uring_cqe *cqes; + void *rings; + int ret; + + sqes = (void *)bpf_io_uring_get_region(ring, IOU_REGION_SQ, + SQ_ENTRIES * sizeof(struct io_uring_sqe)); + rings = (void *)bpf_io_uring_get_region(ring, IOU_REGION_CQ, + cqes_offset + CQ_ENTRIES * sizeof(struct io_uring_cqe)); + if (!rings || !sqes) { + write_result(-1); + return IOU_LOOP_STOP; + } + + sq_hdr = rings + (sq_hdr_offset & 63); + cq_hdr = rings + (cq_hdr_offset & 63); + cqes = rings + cqes_offset; + + unsigned to_wait = cq_hdr->tail - cq_hdr->head; + to_wait = t_min(to_wait, CQ_ENTRIES); + for (int i = 0; i < to_wait; i++) { + struct io_uring_cqe *cqe = &cqes[cq_hdr->head & (CQ_ENTRIES - 1)]; + + if (cqe->user_data != REQ_TOKEN) { + write_result(-3); + return IOU_LOOP_STOP; + } + cq_hdr->head++; + } + + reqs_to_run -= to_wait; + inflight -= to_wait; + write_stats(SLOT_NR_CQES, to_wait); + + if (reqs_to_run <= 0) { + write_result(1); + return IOU_LOOP_STOP; + } + + if (inflight < max_inflight) { + unsigned to_submit = max_inflight - inflight; + + to_submit = t_min(to_submit, reqs_to_run); + + for (int i = 0; i < to_submit; i++) { + struct io_uring_sqe *sqe = sqes + i; + + sqe = &sqes[sq_hdr->tail & (SQ_ENTRIES - 1)]; + *sqe = (struct io_uring_sqe){}; + sqe->opcode = IORING_OP_NOP; + sqe->user_data = REQ_TOKEN; + sq_hdr->tail++; + } + + ret = bpf_io_uring_submit_sqes(ring, to_submit); + if (ret != to_submit) { + write_result(-2); + return IOU_LOOP_STOP; + } + + inflight += to_submit; + write_stats(SLOT_NR_SQES, to_submit); + } + + set_cq_wait(ls, cq_hdr, 1); + return IOU_LOOP_CONTINUE; +} + +SEC(".struct_ops.link") +struct io_uring_bpf_ops basic_ops = { + .loop_step = (void *)link_loop, +}; diff --git a/tools/testing/selftests/io_uring/common.h b/tools/testing/selftests/io_uring/common.h new file mode 100644 index 000000000000..40e3182b8e5a --- /dev/null +++ b/tools/testing/selftests/io_uring/common.h @@ -0,0 +1,6 @@ +#define CQ_ENTRIES 8 +#define SQ_ENTRIES 8 + +#define SLOT_RES 0 +#define SLOT_NR_CQES 1 +#define SLOT_NR_SQES 2 diff --git a/tools/testing/selftests/io_uring/runner.c b/tools/testing/selftests/io_uring/runner.c new file mode 100644 index 000000000000..5fc25ddc20e8 --- /dev/null +++ b/tools/testing/selftests/io_uring/runner.c @@ -0,0 +1,107 @@ +#include +#include +#include +#include + +#include +#include + +#include "basic.bpf.skel.h" +#include "common.h" + +static struct io_uring_params params; +static struct basic *skel; +static struct bpf_link *basic_link; + +#define NR_ITERS 10 + +static void setup_ring(struct io_uring *ring) +{ + int ret; + + memset(¶ms, 0, sizeof(params)); + params.cq_entries = CQ_ENTRIES; + params.flags = IORING_SETUP_SINGLE_ISSUER | + IORING_SETUP_DEFER_TASKRUN | + IORING_SETUP_NO_SQARRAY | + IORING_SETUP_CQSIZE; + + ret = io_uring_queue_init_params(SQ_ENTRIES, ring, ¶ms); + if (ret) { + fprintf(stderr, "ring init failed\n"); + exit(1); + } +} + +static void setup_bpf_ops(struct io_uring *ring) +{ + int ret; + + skel = basic__open(); + if (!skel) { + fprintf(stderr, "can't generate skeleton\n"); + exit(1); + } + + skel->struct_ops.basic_ops->ring_fd = ring->ring_fd; + skel->bss->reqs_to_run = NR_ITERS; + skel->rodata->sq_hdr_offset = params.sq_off.head; + skel->rodata->cq_hdr_offset = params.cq_off.head; + skel->rodata->cqes_offset = params.cq_off.cqes; + + ret = basic__load(skel); + if (ret) { + fprintf(stderr, "failed to load skeleton\n"); + exit(1); + } + + basic_link = bpf_map__attach_struct_ops(skel->maps.basic_ops); + if (!basic_link) { + fprintf(stderr, "failed to attach ops\n"); + exit(1); + } +} + +static void run_ring(struct io_uring *ring) +{ + __s64 res[3] = {}; + int i, ret; + + ret = io_uring_enter(ring->ring_fd, 0, 0, IORING_ENTER_GETEVENTS, NULL); + if (ret) { + fprintf(stderr, "run failed\n"); + exit(1); + } + + for (i = 0; i < 3; i++) { + __u32 key = i; + + ret = bpf_map__lookup_elem(skel->maps.res_map, + &key, sizeof(key), + &res[i], sizeof(res[i]), 0); + if (ret) + fprintf(stderr, "can't read map idx %i: %i\n", i, ret); + } + + if (res[SLOT_RES] != 1) + fprintf(stderr, "run failed: %i\n", (int)res[SLOT_RES]); + if (res[SLOT_NR_CQES] != NR_ITERS) + fprintf(stderr, "unexpected number of CQEs: %i\n", + (int)res[SLOT_NR_CQES]); + if (res[SLOT_NR_SQES] != NR_ITERS) + fprintf(stderr, "unexpected submitted number: %i\n", + (int)res[SLOT_NR_SQES]); +} + +int main() { + struct io_uring ring; + + setup_ring(&ring); + setup_bpf_ops(&ring); + + run_ring(&ring); + + bpf_link__destroy(basic_link); + basic__destroy(skel); + return 0; +} -- 2.52.0