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It needs clang, llvm, bpftool, libbpf, etc. to compile so it's gated on passing BPF_TESTS to make. The Makefile change looks sane but maybe there are better ways, starting with probing all the toolchain availability. Signed-off-by: Pavel Begunkov --- test/Makefile | 44 ++++++++++++++- test/bpf-nops.c | 99 ++++++++++++++++++++++++++++++++++ test/bpf-progs/nops_loop.bpf.c | 99 ++++++++++++++++++++++++++++++++++ 3 files changed, 240 insertions(+), 2 deletions(-) create mode 100644 test/bpf-nops.c create mode 100644 test/bpf-progs/nops_loop.bpf.c diff --git a/test/Makefile b/test/Makefile index 1bbae1cc..0a4f275a 100644 --- a/test/Makefile +++ b/test/Makefile @@ -1,6 +1,12 @@ prefix ?= /usr datadir ?= $(prefix)/share +CLANG ?= clang +BPFTOOL ?= bpftool +BPF_PROGS_DIR = bpf-progs +BPF_OUTPUT = output/bpf/ +BPF_VMLINUX ?= /sys/kernel/btf/vmlinux + INSTALL=install ifneq ($(MAKECMDGOALS),clean) @@ -298,6 +304,17 @@ ifdef CONFIG_HAVE_CXX endif all_targets += sq-full-cpp.t +bpf_tests := bpf-nops.c +opt_deps := + +ifdef BPF_TESTS + override CFLAGS += -I$(BPF_OUTPUT) + override LDFLAGS += -lbpf + test_srcs += $(bpf_tests) + opt_deps += bpf-progs +endif + +$(info flags $(CFLAGS)) test_targets := $(patsubst %.c,%,$(test_srcs)) test_targets := $(patsubst %.cc,%,$(test_targets)) @@ -321,7 +338,7 @@ helpers.o: helpers.c LIBURING := $(shell if [ -e ../src/liburing.a ]; then echo ../src/liburing.a; fi) -%.t: %.c $(helpers) helpers.h $(LIBURING) +%.t: %.c $(helpers) helpers.h $(LIBURING) $(opt_deps) $(QUIET_CC)$(CC) $(CPPFLAGS) $(CFLAGS) -o $@ $< $(helpers) $(LDFLAGS) # @@ -336,6 +353,29 @@ LIBURING := $(shell if [ -e ../src/liburing.a ]; then echo ../src/liburing.a; fi $(patsubst -Wmissing-prototypes,,$(CXXFLAGS)) \ -o $@ $< $(helpers) $(LDFLAGS) +BPF_PROGS = nops_loop.bpf.c + +CLANG_BPF_SYS_INCLUDES ?= $(shell $(CLANG) -v -E - &1 \ + | sed -n '/<...> search starts here:/,/End of search list./{ s| \(/.*\)|-idirafter \1|p }') + +$(BPF_OUTPUT)/vmlinux.h: + mkdir -p $(BPF_OUTPUT) + $(BPFTOOL) btf dump file $(BPF_VMLINUX) format c > $@ + +# Build BPF code +$(BPF_OUTPUT)/%.bpf.o: $(BPF_PROGS_DIR)/%.bpf.c $(wildcard %.h) $(BPF_OUTPUT)/vmlinux.h + mkdir -p ${BPF_OUTPUT} + $(CLANG) -g -O2 -target bpf \ + -I$(BPF_OUTPUT) $(CLANG_BPF_SYS_INCLUDES) \ + -Wno-missing-declarations \ + -c $(filter %.c,$^) -o $(patsubst %.bpf.o,%.tmp.bpf.o,$@) -mcpu=v4 + $(BPFTOOL) gen object $@ $(patsubst %.bpf.o,%.tmp.bpf.o,$@) + +$(BPF_OUTPUT)/%.skel.h: $(BPF_OUTPUT)/%.bpf.o $(BPF_OUTPUT)/vmlinux.h + $(BPFTOOL) gen skeleton $< > $@ + +bpf-progs: $(patsubst %.bpf.c,$(BPF_OUTPUT)/%.bpf.o,$(BPF_PROGS)) \ + $(patsubst %.bpf.c,$(BPF_OUTPUT)/%.skel.h,$(BPF_PROGS)) install: $(test_targets) runtests.sh runtests-loop.sh $(INSTALL) -D -d -m 755 $(datadir)/liburing-test/ @@ -362,4 +402,4 @@ runtests-loop: all runtests-parallel: $(run_test_targets) @echo "All tests passed" -.PHONY: all install clean runtests runtests-loop runtests-parallel +.PHONY: all install clean runtests runtests-loop runtests-parallel bpf-progs diff --git a/test/bpf-nops.c b/test/bpf-nops.c new file mode 100644 index 00000000..3fe6befe --- /dev/null +++ b/test/bpf-nops.c @@ -0,0 +1,99 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#include +#include +#include +#include +#include + +#include "liburing.h" +#include "nops_loop.skel.h" +#include "helpers.h" + +static struct nops_loop_bpf *skel; +static struct bpf_link *nops_loop_bpf_link; + +#define CQ_ENTRIES 8 +#define SQ_ENTRIES 8 +#define NR_ITERS 1000 + +static int setup_ring_ops(struct io_uring *ring) +{ + struct io_uring_params params; + 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 | + IORING_SETUP_SQ_REWIND; + + ret = t_create_ring_params(SQ_ENTRIES, ring, ¶ms); + if (ret == T_SETUP_SKIP) { + printf("Can't setup a ring, skip\n"); + return T_EXIT_SKIP; + } + if (ret != T_SETUP_OK) + return T_EXIT_FAIL; + + skel = nops_loop_bpf__open(); + if (!skel) { + fprintf(stderr, "can't generate skeleton\n"); + return T_EXIT_FAIL; + } + + skel->struct_ops.nops_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; + skel->rodata->cq_entries = CQ_ENTRIES; + skel->rodata->sq_entries = SQ_ENTRIES; + + ret = nops_loop_bpf__load(skel); + if (ret) { + if (ret == -ESRCH) { + printf("io_uring BPF ops are not supported\n"); + return T_EXIT_SKIP; + } + fprintf(stderr, "failed to load skeleton\n"); + return T_EXIT_FAIL; + } + + nops_loop_bpf_link = bpf_map__attach_struct_ops(skel->maps.nops_ops); + if (!nops_loop_bpf_link) { + fprintf(stderr, "failed to attach ops\n"); + return T_EXIT_FAIL; + } + return T_EXIT_PASS; +} + +int main() +{ + struct io_uring ring; + unsigned left; + int ret; + + ret = setup_ring_ops(&ring); + if (ret != T_EXIT_PASS) + return ret; + + ret = io_uring_enter(ring.ring_fd, 0, 0, IORING_ENTER_GETEVENTS, NULL); + if (ret) { + fprintf(stderr, "run failed\n"); + return T_EXIT_FAIL; + } + + left = skel->bss->reqs_to_run; + if (left) { + fprintf(stderr, "Run failed, couldn't submit all nops %i / %i\n", + NR_ITERS - left, NR_ITERS); + return T_EXIT_FAIL; + } + + bpf_link__destroy(nops_loop_bpf_link); + nops_loop_bpf__destroy(skel); + io_uring_queue_exit(&ring); + return T_EXIT_PASS; +} diff --git a/test/bpf-progs/nops_loop.bpf.c b/test/bpf-progs/nops_loop.bpf.c new file mode 100644 index 00000000..00075bb6 --- /dev/null +++ b/test/bpf-progs/nops_loop.bpf.c @@ -0,0 +1,99 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#include "vmlinux.h" +#include +#include +#include + +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; +const volatile unsigned cq_entries; +const volatile unsigned sq_entries; + +unsigned reqs_inflight = 0; +int reqs_to_run; + +#define t_min(a, b) ((a) < (b) ? (a) : (b)) + +static unsigned nr_to_submit(void) +{ + unsigned to_submit = 0; + unsigned inflight = reqs_inflight; + + if (inflight < max_inflight) { + to_submit = max_inflight - inflight; + to_submit = t_min(to_submit, reqs_to_run - inflight); + } + return to_submit; +} + +SEC("struct_ops.s/nops_loop_step") +int BPF_PROG(nops_loop_step, struct io_ring_ctx *ring, struct iou_loop_params *ls) +{ + struct io_uring_sqe *sqes; + struct io_uring_cqe *cqes; + struct io_uring *cq_hdr; + unsigned to_submit; + unsigned to_wait; + unsigned nr_cqes; + void *rings; + int ret, i; + + 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) + return IOU_LOOP_STOP; + cq_hdr = rings + cq_hdr_offset; + cqes = rings + cqes_offset; + + to_submit = nr_to_submit(); + if (to_submit) { + for (i = 0; i < to_submit; i++) { + struct io_uring_sqe *sqe = &sqes[i]; + + *sqe = (struct io_uring_sqe){}; + sqe->opcode = IORING_OP_NOP; + sqe->user_data = REQ_TOKEN; + } + + ret = bpf_io_uring_submit_sqes(ring, to_submit); + if (ret != to_submit) + return IOU_LOOP_STOP; + reqs_inflight += to_submit; + } + + nr_cqes = cq_hdr->tail - cq_hdr->head; + nr_cqes = t_min(nr_cqes, max_inflight); + for (i = 0; i < nr_cqes; i++) { + struct io_uring_cqe *cqe = &cqes[cq_hdr->head & (cq_entries - 1)]; + + if (cqe->user_data != REQ_TOKEN) + return IOU_LOOP_STOP; + cq_hdr->head++; + } + + reqs_inflight -= nr_cqes; + reqs_to_run -= nr_cqes; + + if (reqs_to_run <= 0 && !reqs_inflight) + return IOU_LOOP_STOP; + + to_wait = reqs_inflight; + /* Don't sleep if there are still CQEs left */ + if (cq_hdr->tail != cq_hdr->head) + to_wait = 0; + ls->cq_wait_idx = cq_hdr->head + to_wait; + return IOU_LOOP_CONTINUE; +} + +SEC(".struct_ops.link") +struct io_uring_bpf_ops nops_ops = { + .loop_step = (void *)nops_loop_step, +}; -- 2.53.0