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[PATCH bpf-next v3] selftests/bpf: Add LPM trie microbenchmarks

by Matt Fleming

From: Matt Fleming <mfleming(a)cloudflare.com> Add benchmarks for the standard set of operations: lookup, update, delete. Also, include a benchmark for trie_free() which is known to have terrible performance for maps with many entries. Benchmarks operate on tries without gaps in the key range, i.e. each test begins with a trie with valid keys in the range [0, nr_entries). This is intended to cause maximum branching when traversing the trie. All measurements are recorded inside the kernel to remove syscall overhead. Most benchmarks run an XDP program to generate stats but free needs to collect latencies using fentry/fexit on map_free_deferred() because it's not possible to use fentry directly on lpm_trie.c since commit c83508da5620 ("bpf: Avoid deadlock caused by nested kprobe and fentry bpf programs") and there's no way to create/destroy a map from within an XDP program. Here is example output from an AMD EPYC 9684X 96-Core machine for each of the benchmarks using a trie with 10K entries and a 32-bit prefix length, e.g. $ ./bench lpm-trie-$op \ --prefix_len=32 \ --producers=1 \ --nr_entries=10000 lookup: throughput 7.423 ± 0.023 M ops/s ( 7.423M ops/prod), latency 134.710 ns/op update: throughput 2.643 ± 0.015 M ops/s ( 2.643M ops/prod), latency 378.310 ns/op delete: throughput 0.712 ± 0.008 M ops/s ( 0.712M ops/prod), latency 1405.152 ns/op free: throughput 0.574 ± 0.003 K ops/s ( 0.574K ops/prod), latency 1.743 ms/op Tested-by: Jesper Dangaard Brouer <hawk(a)kernel.org> Reviewed-by: Jesper Dangaard Brouer <hawk(a)kernel.org> Signed-off-by: Matt Fleming <mfleming(a)cloudflare.com> --- Changes in v3: - Replace BPF_CORE_READ() with BPF_CORE_READ_STR_INTO() to avoid gcc-bpf CI build failure Changes in v2: - Add Jesper's Tested-by and Revewied-by tags - Remove use of atomic_*() in favour of __sync_add_and_fetch() - Use a file-local 'deleted_entries' in the DELETE op benchmark and add a comment explaining why non-atomic accesses are safe. - Bump 'hits' with the number of bpf_loop() loops actually executed tools/testing/selftests/bpf/Makefile | 2 + tools/testing/selftests/bpf/bench.c | 10 + tools/testing/selftests/bpf/bench.h | 1 + .../selftests/bpf/benchs/bench_lpm_trie_map.c | 337 ++++++++++++++++++ .../selftests/bpf/progs/lpm_trie_bench.c | 171 +++++++++ .../selftests/bpf/progs/lpm_trie_map.c | 19 + 6 files changed, 540 insertions(+) create mode 100644 tools/testing/selftests/bpf/benchs/bench_lpm_trie_map.c create mode 100644 tools/testing/selftests/bpf/progs/lpm_trie_bench.c create mode 100644 tools/testing/selftests/bpf/progs/lpm_trie_map.c diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index 910d8d6402ef..10a5f1d0fa41 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -815,6 +815,7 @@ $(OUTPUT)/bench_bpf_hashmap_lookup.o: $(OUTPUT)/bpf_hashmap_lookup.skel.h $(OUTPUT)/bench_htab_mem.o: $(OUTPUT)/htab_mem_bench.skel.h $(OUTPUT)/bench_bpf_crypto.o: $(OUTPUT)/crypto_bench.skel.h $(OUTPUT)/bench_sockmap.o: $(OUTPUT)/bench_sockmap_prog.skel.h +$(OUTPUT)/bench_lpm_trie_map.o: $(OUTPUT)/lpm_trie_bench.skel.h $(OUTPUT)/lpm_trie_map.skel.h $(OUTPUT)/bench.o: bench.h testing_helpers.h $(BPFOBJ) $(OUTPUT)/bench: LDLIBS += -lm $(OUTPUT)/bench: $(OUTPUT)/bench.o \ @@ -836,6 +837,7 @@ $(OUTPUT)/bench: $(OUTPUT)/bench.o \ $(OUTPUT)/bench_htab_mem.o \ $(OUTPUT)/bench_bpf_crypto.o \ $(OUTPUT)/bench_sockmap.o \ + $(OUTPUT)/bench_lpm_trie_map.o \ # $(call msg,BINARY,,$@) $(Q)$(CC) $(CFLAGS) $(LDFLAGS) $(filter %.a %.o,$^) $(LDLIBS) -o $@ diff --git a/tools/testing/selftests/bpf/bench.c b/tools/testing/selftests/bpf/bench.c index ddd73d06a1eb..fd15f60fd5a8 100644 --- a/tools/testing/selftests/bpf/bench.c +++ b/tools/testing/selftests/bpf/bench.c @@ -284,6 +284,7 @@ extern struct argp bench_htab_mem_argp; extern struct argp bench_trigger_batch_argp; extern struct argp bench_crypto_argp; extern struct argp bench_sockmap_argp; +extern struct argp bench_lpm_trie_map_argp; static const struct argp_child bench_parsers[] = { { &bench_ringbufs_argp, 0, "Ring buffers benchmark", 0 }, @@ -299,6 +300,7 @@ static const struct argp_child bench_parsers[] = { { &bench_trigger_batch_argp, 0, "BPF triggering benchmark", 0 }, { &bench_crypto_argp, 0, "bpf crypto benchmark", 0 }, { &bench_sockmap_argp, 0, "bpf sockmap benchmark", 0 }, + { &bench_lpm_trie_map_argp, 0, "LPM trie map benchmark", 0 }, {}, }; @@ -558,6 +560,10 @@ extern const struct bench bench_htab_mem; extern const struct bench bench_crypto_encrypt; extern const struct bench bench_crypto_decrypt; extern const struct bench bench_sockmap; +extern const struct bench bench_lpm_trie_lookup; +extern const struct bench bench_lpm_trie_update; +extern const struct bench bench_lpm_trie_delete; +extern const struct bench bench_lpm_trie_free; static const struct bench *benchs[] = { &bench_count_global, @@ -625,6 +631,10 @@ static const struct bench *benchs[] = { &bench_crypto_encrypt, &bench_crypto_decrypt, &bench_sockmap, + &bench_lpm_trie_lookup, + &bench_lpm_trie_update, + &bench_lpm_trie_delete, + &bench_lpm_trie_free, }; static void find_benchmark(void) diff --git a/tools/testing/selftests/bpf/bench.h b/tools/testing/selftests/bpf/bench.h index 005c401b3e22..bea323820ffb 100644 --- a/tools/testing/selftests/bpf/bench.h +++ b/tools/testing/selftests/bpf/bench.h @@ -46,6 +46,7 @@ struct bench_res { unsigned long gp_ns; unsigned long gp_ct; unsigned int stime; + unsigned long duration_ns; }; struct bench { diff --git a/tools/testing/selftests/bpf/benchs/bench_lpm_trie_map.c b/tools/testing/selftests/bpf/benchs/bench_lpm_trie_map.c new file mode 100644 index 000000000000..435b5c7ceee9 --- /dev/null +++ b/tools/testing/selftests/bpf/benchs/bench_lpm_trie_map.c @@ -0,0 +1,337 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2025 Cloudflare */ + +/* + * All of these benchmarks operate on tries with keys in the range + * [0, args.nr_entries), i.e. there are no gaps or partially filled + * branches of the trie for any key < args.nr_entries. + * + * This gives an idea of worst-case behaviour. + */ + +#include <argp.h> +#include <linux/time64.h> +#include <linux/if_ether.h> +#include "lpm_trie_bench.skel.h" +#include "lpm_trie_map.skel.h" +#include "bench.h" +#include "testing_helpers.h" + +static struct ctx { + struct lpm_trie_bench *bench; +} ctx; + +static struct { + __u32 nr_entries; + __u32 prefixlen; +} args = { + .nr_entries = 10000, + .prefixlen = 32, +}; + +enum { + ARG_NR_ENTRIES = 9000, + ARG_PREFIX_LEN, +}; + +static const struct argp_option opts[] = { + { "nr_entries", ARG_NR_ENTRIES, "NR_ENTRIES", 0, + "Number of unique entries in the LPM trie" }, + { "prefix_len", ARG_PREFIX_LEN, "PREFIX_LEN", 0, + "Number of prefix bits to use in the LPM trie" }, + {}, +}; + +static error_t lpm_parse_arg(int key, char *arg, struct argp_state *state) +{ + long ret; + + switch (key) { + case ARG_NR_ENTRIES: + ret = strtol(arg, NULL, 10); + if (ret < 1 || ret > UINT_MAX) { + fprintf(stderr, "Invalid nr_entries count."); + argp_usage(state); + } + args.nr_entries = ret; + break; + case ARG_PREFIX_LEN: + ret = strtol(arg, NULL, 10); + if (ret < 1 || ret > UINT_MAX) { + fprintf(stderr, "Invalid prefix_len value."); + argp_usage(state); + } + args.prefixlen = ret; + break; + default: + return ARGP_ERR_UNKNOWN; + } + return 0; +} + +const struct argp bench_lpm_trie_map_argp = { + .options = opts, + .parser = lpm_parse_arg, +}; + +static void __lpm_validate(void) +{ + if (env.consumer_cnt != 0) { + fprintf(stderr, "benchmark doesn't support consumer!\n"); + exit(1); + } + + if ((1UL << args.prefixlen) < args.nr_entries) { + fprintf(stderr, "prefix_len value too small for nr_entries!\n"); + exit(1); + }; +} + +enum { OP_LOOKUP = 1, OP_UPDATE, OP_DELETE, OP_FREE }; + +static void lpm_delete_validate(void) +{ + __lpm_validate(); + + if (env.producer_cnt != 1) { + fprintf(stderr, + "lpm-trie-delete requires a single producer!\n"); + exit(1); + } +} + +static void lpm_free_validate(void) +{ + __lpm_validate(); + + if (env.producer_cnt != 1) { + fprintf(stderr, "lpm-trie-free requires a single producer!\n"); + exit(1); + } +} + +static void fill_map(int map_fd) +{ + int i, err; + + for (i = 0; i < args.nr_entries; i++) { + struct trie_key { + __u32 prefixlen; + __u32 data; + } key = { args.prefixlen, i }; + __u32 val = 1; + + err = bpf_map_update_elem(map_fd, &key, &val, BPF_NOEXIST); + if (err) { + fprintf(stderr, "failed to add key %d to map: %d\n", + key.data, -err); + exit(1); + } + } +} + +static void __lpm_setup(void) +{ + ctx.bench = lpm_trie_bench__open_and_load(); + if (!ctx.bench) { + fprintf(stderr, "failed to open skeleton\n"); + exit(1); + } + + ctx.bench->bss->nr_entries = args.nr_entries; + ctx.bench->bss->prefixlen = args.prefixlen; + + if (lpm_trie_bench__attach(ctx.bench)) { + fprintf(stderr, "failed to attach skeleton\n"); + exit(1); + } +} + +static void lpm_setup(void) +{ + int fd; + + __lpm_setup(); + + fd = bpf_map__fd(ctx.bench->maps.trie_map); + fill_map(fd); +} + +static void lpm_lookup_setup(void) +{ + lpm_setup(); + + ctx.bench->bss->op = OP_LOOKUP; +} + +static void lpm_update_setup(void) +{ + lpm_setup(); + + ctx.bench->bss->op = OP_UPDATE; +} + +static void lpm_delete_setup(void) +{ + lpm_setup(); + + ctx.bench->bss->op = OP_DELETE; +} + +static void lpm_free_setup(void) +{ + __lpm_setup(); + ctx.bench->bss->op = OP_FREE; +} + +static void lpm_measure(struct bench_res *res) +{ + res->hits = atomic_swap(&ctx.bench->bss->hits, 0); + res->duration_ns = atomic_swap(&ctx.bench->bss->duration_ns, 0); +} + +/* For LOOKUP, UPDATE, and DELETE */ +static void *lpm_producer(void *unused __always_unused) +{ + int err; + char in[ETH_HLEN]; /* unused */ + + LIBBPF_OPTS(bpf_test_run_opts, opts, .data_in = in, + .data_size_in = sizeof(in), .repeat = 1, ); + + while (true) { + int fd = bpf_program__fd(ctx.bench->progs.run_bench); + err = bpf_prog_test_run_opts(fd, &opts); + if (err) { + fprintf(stderr, "failed to run BPF prog: %d\n", err); + exit(1); + } + + if (opts.retval < 0) { + fprintf(stderr, "BPF prog returned error: %d\n", + opts.retval); + exit(1); + } + + if (ctx.bench->bss->op == OP_DELETE && opts.retval == 1) { + /* trie_map needs to be refilled */ + fill_map(bpf_map__fd(ctx.bench->maps.trie_map)); + } + } + + return NULL; +} + +static void *lpm_free_producer(void *unused __always_unused) +{ + while (true) { + struct lpm_trie_map *skel; + + skel = lpm_trie_map__open_and_load(); + if (!skel) { + fprintf(stderr, "failed to open skeleton\n"); + exit(1); + } + + fill_map(bpf_map__fd(skel->maps.trie_free_map)); + lpm_trie_map__destroy(skel); + } + + return NULL; +} + +static void free_ops_report_progress(int iter, struct bench_res *res, + long delta_ns) +{ + double hits_per_sec, hits_per_prod; + double rate_divisor = 1000.0; + char rate = 'K'; + + hits_per_sec = res->hits / (res->duration_ns / (double)NSEC_PER_SEC) / + rate_divisor; + hits_per_prod = hits_per_sec / env.producer_cnt; + + printf("Iter %3d (%7.3lfus): ", iter, + (delta_ns - NSEC_PER_SEC) / 1000.0); + printf("hits %8.3lf%c/s (%7.3lf%c/prod)\n", hits_per_sec, rate, + hits_per_prod, rate); +} + +static void free_ops_report_final(struct bench_res res[], int res_cnt) +{ + double hits_mean = 0.0, hits_stddev = 0.0; + double lat_divisor = 1000000.0; + double rate_divisor = 1000.0; + const char *unit = "ms"; + double latency = 0.0; + char rate = 'K'; + int i; + + for (i = 0; i < res_cnt; i++) { + double val = res[i].hits / rate_divisor / + (res[i].duration_ns / (double)NSEC_PER_SEC); + hits_mean += val / (0.0 + res_cnt); + latency += res[i].duration_ns / res[i].hits / (0.0 + res_cnt); + } + + if (res_cnt > 1) { + for (i = 0; i < res_cnt; i++) { + double val = + res[i].hits / rate_divisor / + (res[i].duration_ns / (double)NSEC_PER_SEC); + hits_stddev += (hits_mean - val) * (hits_mean - val) / + (res_cnt - 1.0); + } + + hits_stddev = sqrt(hits_stddev); + } + printf("Summary: throughput %8.3lf \u00B1 %5.3lf %c ops/s (%7.3lf%c ops/prod), ", + hits_mean, hits_stddev, rate, hits_mean / env.producer_cnt, + rate); + printf("latency %8.3lf %s/op\n", + latency / lat_divisor / env.producer_cnt, unit); +} + +const struct bench bench_lpm_trie_lookup = { + .name = "lpm-trie-lookup", + .argp = &bench_lpm_trie_map_argp, + .validate = __lpm_validate, + .setup = lpm_lookup_setup, + .producer_thread = lpm_producer, + .measure = lpm_measure, + .report_progress = ops_report_progress, + .report_final = ops_report_final, +}; + +const struct bench bench_lpm_trie_update = { + .name = "lpm-trie-update", + .argp = &bench_lpm_trie_map_argp, + .validate = __lpm_validate, + .setup = lpm_update_setup, + .producer_thread = lpm_producer, + .measure = lpm_measure, + .report_progress = ops_report_progress, + .report_final = ops_report_final, +}; + +const struct bench bench_lpm_trie_delete = { + .name = "lpm-trie-delete", + .argp = &bench_lpm_trie_map_argp, + .validate = lpm_delete_validate, + .setup = lpm_delete_setup, + .producer_thread = lpm_producer, + .measure = lpm_measure, + .report_progress = ops_report_progress, + .report_final = ops_report_final, +}; + +const struct bench bench_lpm_trie_free = { + .name = "lpm-trie-free", + .argp = &bench_lpm_trie_map_argp, + .validate = lpm_free_validate, + .setup = lpm_free_setup, + .producer_thread = lpm_free_producer, + .measure = lpm_measure, + .report_progress = free_ops_report_progress, + .report_final = free_ops_report_final, +}; diff --git a/tools/testing/selftests/bpf/progs/lpm_trie_bench.c b/tools/testing/selftests/bpf/progs/lpm_trie_bench.c new file mode 100644 index 000000000000..522e1cbef490 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/lpm_trie_bench.c @@ -0,0 +1,171 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2025 Cloudflare */ + +#include <vmlinux.h> +#include <bpf/bpf_tracing.h> +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_core_read.h> +#include "bpf_misc.h" + +#define BPF_OBJ_NAME_LEN 16U +#define MAX_ENTRIES 100000000 +#define NR_LOOPS 10000 + +struct trie_key { + __u32 prefixlen; + __u32 data; +}; + +char _license[] SEC("license") = "GPL"; + +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __uint(max_entries, 512); + __type(key, struct bpf_map *); + __type(value, __u64); +} latency_free_start SEC(".maps"); + +/* Filled by userspace. See fill_map() in bench_lpm_trie_map.c */ +struct { + __uint(type, BPF_MAP_TYPE_LPM_TRIE); + __type(key, struct trie_key); + __type(value, __u32); + __uint(map_flags, BPF_F_NO_PREALLOC); + __uint(max_entries, MAX_ENTRIES); +} trie_map SEC(".maps"); + +long hits; +long duration_ns; + +/* Configured from userspace */ +__u32 nr_entries; +__u32 prefixlen; +__u8 op; + +SEC("fentry/bpf_map_free_deferred") +int BPF_PROG(trie_free_entry, struct work_struct *work) +{ + struct bpf_map *map = container_of(work, struct bpf_map, work); + char name[BPF_OBJ_NAME_LEN]; + u32 map_type; + __u64 val; + + map_type = BPF_CORE_READ(map, map_type); + if (map_type != BPF_MAP_TYPE_LPM_TRIE) + return 0; + + /* + * Ideally we'd have access to the map ID but that's already + * freed before we enter trie_free(). + */ + BPF_CORE_READ_STR_INTO(&name, map, name); + if (bpf_strncmp(name, BPF_OBJ_NAME_LEN, "trie_free_map")) + return 0; + + val = bpf_ktime_get_ns(); + bpf_map_update_elem(&latency_free_start, &map, &val, BPF_ANY); + + return 0; +} + +SEC("fexit/bpf_map_free_deferred") +int BPF_PROG(trie_free_exit, struct work_struct *work) +{ + struct bpf_map *map = container_of(work, struct bpf_map, work); + __u64 *val; + + val = bpf_map_lookup_elem(&latency_free_start, &map); + if (val) { + __sync_add_and_fetch(&duration_ns, bpf_ktime_get_ns() - *val); + __sync_add_and_fetch(&hits, 1); + bpf_map_delete_elem(&latency_free_start, &map); + } + + return 0; +} + +static void gen_random_key(struct trie_key *key) +{ + key->prefixlen = prefixlen; + key->data = bpf_get_prandom_u32() % nr_entries; +} + +static int lookup(__u32 index, __u32 *unused) +{ + struct trie_key key; + + gen_random_key(&key); + bpf_map_lookup_elem(&trie_map, &key); + return 0; +} + +static int update(__u32 index, __u32 *unused) +{ + struct trie_key key; + u32 val = bpf_get_prandom_u32(); + + gen_random_key(&key); + bpf_map_update_elem(&trie_map, &key, &val, BPF_EXIST); + return 0; +} + +static __u32 deleted_entries; + +static int delete (__u32 index, bool *need_refill) +{ + struct trie_key key = { + .data = deleted_entries, + .prefixlen = prefixlen, + }; + + bpf_map_delete_elem(&trie_map, &key); + + /* Do we need to refill the map? */ + if (++deleted_entries == nr_entries) { + /* + * Atomicity isn't required because DELETE only supports + * one producer running concurrently. What we need is a + * way to track how many entries have been deleted from + * the trie between consecutive invocations of the BPF + * prog because a single bpf_loop() call might not + * delete all entries, e.g. when NR_LOOPS < nr_entries. + */ + deleted_entries = 0; + *need_refill = true; + return 1; + } + + return 0; +} + +SEC("xdp") +int BPF_PROG(run_bench) +{ + bool need_refill = false; + u64 start, delta; + int loops; + + start = bpf_ktime_get_ns(); + + switch (op) { + case 1: + loops = bpf_loop(NR_LOOPS, lookup, NULL, 0); + break; + case 2: + loops = bpf_loop(NR_LOOPS, update, NULL, 0); + break; + case 3: + loops = bpf_loop(NR_LOOPS, delete, &need_refill, 0); + break; + default: + bpf_printk("invalid benchmark operation\n"); + return -1; + } + + delta = bpf_ktime_get_ns() - start; + + __sync_add_and_fetch(&duration_ns, delta); + __sync_add_and_fetch(&hits, loops); + + return need_refill; +} diff --git a/tools/testing/selftests/bpf/progs/lpm_trie_map.c b/tools/testing/selftests/bpf/progs/lpm_trie_map.c new file mode 100644 index 000000000000..2ab43e2cd6c6 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/lpm_trie_map.c @@ -0,0 +1,19 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_tracing.h> + +#define MAX_ENTRIES 100000000 + +struct trie_key { + __u32 prefixlen; + __u32 data; +}; + +struct { + __uint(type, BPF_MAP_TYPE_LPM_TRIE); + __type(key, struct trie_key); + __type(value, __u32); + __uint(map_flags, BPF_F_NO_PREALLOC); + __uint(max_entries, MAX_ENTRIES); +} trie_free_map SEC(".maps"); -- 2.34.1

2 months, 3 weeks

3
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[PATCH] KVM: selftests: fix minor typo in cpumodel_subfuncs

by Gopi Krishna Menon

Specifically, fix spelling of "available" in main function. Signed-off-by: Gopi Krishna Menon <krishnagopi487(a)gmail.com> --- tools/testing/selftests/kvm/s390/cpumodel_subfuncs_test.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/kvm/s390/cpumodel_subfuncs_test.c b/tools/testing/selftests/kvm/s390/cpumodel_subfuncs_test.c index 27255880dabd..aded795d42be 100644 --- a/tools/testing/selftests/kvm/s390/cpumodel_subfuncs_test.c +++ b/tools/testing/selftests/kvm/s390/cpumodel_subfuncs_test.c @@ -291,7 +291,7 @@ int main(int argc, char *argv[]) ksft_test_result_pass("%s\n", testlist[idx].subfunc_name); free(array); } else { - ksft_test_result_skip("%s feature is not avaialable\n", + ksft_test_result_skip("%s feature is not available\n", testlist[idx].subfunc_name); } } -- 2.43.0

2 months, 3 weeks

1
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[PATCH 0/3] kho: fixes and cleanups

by Mike Rapoport

From: "Mike Rapoport (Microsoft)" <rppt(a)kernel.org> Hi, These are small KHO and KHO test fixes and cleanups Mike Rapoport (Microsoft) (3): kho: allow scratch areas with zero size lib/test_kho: fixes for error handling selftest/kho: update generation of initrd kernel/kexec_handover.c | 7 +++- lib/test_kho.c | 52 +++++++++++++++++---------- tools/testing/selftests/kho/init.c | 13 +++---- tools/testing/selftests/kho/vmtest.sh | 28 ++++++++------- 4 files changed, 58 insertions(+), 42 deletions(-) base-commit: 8f5ae30d69d7543eee0d70083daf4de8fe15d585 -- 2.47.2

2 months, 3 weeks

2
7
0 0

[PATCH v2 0/7] kunit: Refactor and extend KUnit's parameterized testing framework

by Marie Zhussupova

Hello! KUnit offers a parameterized testing framework, where tests can be run multiple times with different inputs. However, the current implementation uses the same `struct kunit` for each parameter run. After each run, the test context gets cleaned up, which creates the following limitations: a. There is no way to store resources that are accessible across the individual parameter runs. b. It's not possible to pass additional context, besides the previous parameter (and potentially anything else that is stored in the current test context), to the parameter generator function. c. Test users are restricted to using pre-defined static arrays of parameter objects or generate_params() to define their parameters. There is no flexibility to make a custom dynamic array without using generate_params(), which can be complex if generating the next parameter depends on more than just the single previous parameter. This patch series resolves these limitations by: 1. [P 1] Giving each parameterized run its own `struct kunit`. It will remove the need to manage state, such as resetting the `test->priv` field or the `test->status_comment` after every parameter run. 2. [P 1] Introducing parameterized test context available to all parameter runs through the parent pointer of type `struct kunit`. This context won't be used to execute any test logic, but will instead be used for storing shared resources. Each parameter run context will have a reference to that parent instance and thus, have access to those resources. 3. [P 2] Introducing param_init() and param_exit() functions that can initialize and exit the parameterized test context. They will run once before and after the parameterized test. param_init() can be used to add resources to share between parameter runs, pass parameter arrays, and any other setup logic. While param_exit() can be used to clean up resources that were not managed by the parameterized test, and any other teardown logic. 4. [P 3] Passing the parameterized test context as an additional argument to generate_params(). This provides generate_params() with more context, making parameter generation much more flexible. The generate_params() implementations in the KCSAN and drm/xe tests have been adapted to match the new function pointer signature. 5. [P 4] Introducing a `params_array` field in `struct kunit`. This will allow the parameterized test context to have direct storage of the parameter array, enabling features like using dynamic parameter arrays or using context beyond just the previous parameter. This will also enable outputting the KTAP test plan for a parameterized test when the parameter count is available. Patches 5 and 6 add examples tests to lib/kunit/kunit-example-test.c to showcase the new features and patch 7 updates the KUnit documentation to reflect all the framework changes. Thank you! -Marie --- Changes in v2: Link to v1 of this patch series: https://lore.kernel.org/all/20250729193647.3410634-1-marievic@google.com/ - Establish parameterized testing terminology: - "parameterized test" will refer to the group of all runs of a single test function with different parameters. - "parameter run" will refer to the execution of the test case function with a single parameter. - "parameterized test context" is the `struct kunit` that holds the context for the entire parameterized test. - "parameter run context" is the `struct kunit` that holds the context of the individual parameter run. - A test is defined to be a parameterized tests if it was registered with a generator function. - Make comment edits to reflect the established terminology. - Require users to manually pass kunit_array_gen_params() to KUNIT_CASE_PARAM_WITH_INIT() as the generator function, unless they want to provide their own generator function, if the parameter array was registered in param_init(). This is to be consistent with the definition of a parameterized test, i.e. generate_params() is never NULL if it's a parameterized test. - Change name of kunit_get_next_param_and_desc() to kunit_array_gen_params(). - Other minor function name changes such as removing the "__" prefix in front of internal functions. - Change signature of get_description() in `struct params_array` to accept the parameterized test context, as well. - Output the KTAP test plan for a parameterized test when the parameter count is available. - Cover letter was made more concise. - Edits to the example tests. - Fix bug of parameterized test init/exit logic being done outside of the parameterized test check. - Fix bugs identified by the kernel test robot. --- Marie Zhussupova (7): kunit: Add parent kunit for parameterized test context kunit: Introduce param_init/exit for parameterized test context management kunit: Pass parameterized test context to generate_params() kunit: Enable direct registration of parameter arrays to a KUnit test kunit: Add example parameterized test with shared resource management using the Resource API kunit: Add example parameterized test with direct dynamic parameter array setup Documentation: kunit: Document new parameterized test features Documentation/dev-tools/kunit/usage.rst | 342 +++++++++++++++++++++++- drivers/gpu/drm/xe/tests/xe_pci.c | 2 +- include/kunit/test.h | 95 ++++++- kernel/kcsan/kcsan_test.c | 2 +- lib/kunit/kunit-example-test.c | 222 +++++++++++++++ lib/kunit/test.c | 87 ++++-- rust/kernel/kunit.rs | 4 + 7 files changed, 726 insertions(+), 28 deletions(-) -- 2.51.0.rc0.205.g4a044479a3-goog

2 months, 3 weeks

5
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[PATCH][next] selftests/mm: Fix spelling mistake "mrmeap" -> "mremap"

by Colin Ian King

There are spelling mistakes in perror message. Fix these. Signed-off-by: Colin Ian King <colin.i.king(a)gmail.com> --- V2: fix typo fixes, I need more coffee --- tools/testing/selftests/mm/mremap_test.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/mm/mremap_test.c b/tools/testing/selftests/mm/mremap_test.c index 5bd52a951cbd..e289bb1112db 100644 --- a/tools/testing/selftests/mm/mremap_test.c +++ b/tools/testing/selftests/mm/mremap_test.c @@ -846,7 +846,7 @@ static void mremap_move_multi_invalid_vmas(FILE *maps_fp, } if (err != EFAULT) { errno = err; - perror("mrmeap() unexpected error"); + perror("mremap() unexpected error"); success = false; goto out_unmap; } @@ -899,7 +899,7 @@ static void mremap_move_multi_invalid_vmas(FILE *maps_fp, } if (err != EFAULT) { errno = err; - perror("mrmeap() unexpected error"); + perror("mremap() unexpected error"); success = false; goto out_unmap; } @@ -948,7 +948,7 @@ static void mremap_move_multi_invalid_vmas(FILE *maps_fp, } if (err != EFAULT) { errno = err; - perror("mrmeap() unexpected error"); + perror("mremap() unexpected error"); success = false; goto out_unmap; } -- 2.50.1

2 months, 3 weeks

2
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[PATCH][next] selftests/mm: Fix spelling mistake "mrmeap" -> "mremap"

by Colin Ian King

There are spelling mistakes in perror message. Fix these. Signed-off-by: Colin Ian King <colin.i.king(a)gmail.com> --- tools/testing/selftests/mm/mremap_test.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/mm/mremap_test.c b/tools/testing/selftests/mm/mremap_test.c index 5bd52a951cbd..e289bb1112db 100644 --- a/tools/testing/selftests/mm/mremap_test.c +++ b/tools/testing/selftests/mm/mremap_test.c @@ -846,7 +846,7 @@ static void mremap_move_multi_invalid_vmas(FILE *maps_fp, } if (err != EFAULT) { errno = err; - perror("mrmeap() unexpected error"); + perror("mremap() unexpected error"); success = false; goto out_unmap; } @@ -899,7 +899,7 @@ static void mremap_move_multi_invalid_vmas(FILE *maps_fp, } if (err != EFAULT) { errno = err; - perror("mrmeap() unexpected error"); + perror("remapp() unexpected error"); success = false; goto out_unmap; } @@ -948,7 +948,7 @@ static void mremap_move_multi_invalid_vmas(FILE *maps_fp, } if (err != EFAULT) { errno = err; - perror("mrmeap() unexpected error"); + perror("remapp() unexpected error"); success = false; goto out_unmap; } -- 2.50.1

2 months, 3 weeks

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[PATCH] kunit: tool: Parse skipped tests from kselftest.h

by Thomas Weißschuh

Skipped tests reported by kselftest.h use a different format than KTAP, there is no explicit test name. Normally the test name is part of the free-form string after the SKIP keyword: ok 3 # SKIP test: some reason Extend the parser to handle those correctly. Use the free-form string as test name instead. Signed-off-by: Thomas Weißschuh <thomas.weissschuh(a)linutronix.de> Reviewed-by: David Gow <davidgow(a)google.com> --- These patches where originally part of my series "kunit: Introduce UAPI testing framework" [0], but that isn't going anywhere right now and the patches are useful on their own. Both series would go in through the KUnit tree in any case, so there is no potential for conflicts. [0] https://lore.kernel.org/lkml/20250717-kunit-kselftests-v5-0-442b711cde2e@li… --- tools/testing/kunit/kunit_parser.py | 8 +++++--- tools/testing/kunit/test_data/test_is_test_passed-kselftest.log | 3 ++- 2 files changed, 7 insertions(+), 4 deletions(-) diff --git a/tools/testing/kunit/kunit_parser.py b/tools/testing/kunit/kunit_parser.py index c176487356e6c94882046b19ea696d750905b8d5..333cd3a4a56b6f26c10aa1a5ecec9858bc57fbd7 100644 --- a/tools/testing/kunit/kunit_parser.py +++ b/tools/testing/kunit/kunit_parser.py @@ -352,9 +352,9 @@ def parse_test_plan(lines: LineStream, test: Test) -> bool: lines.pop() return True -TEST_RESULT = re.compile(r'^\s*(ok|not ok) ([0-9]+) (- )?([^#]*)( # .*)?$') +TEST_RESULT = re.compile(r'^\s*(ok|not ok) ([0-9]+) ?(- )?([^#]*)( # .*)?$') -TEST_RESULT_SKIP = re.compile(r'^\s*(ok|not ok) ([0-9]+) (- )?(.*) # SKIP(.*)$') +TEST_RESULT_SKIP = re.compile(r'^\s*(ok|not ok) ([0-9]+) ?(- )?(.*) # SKIP ?(.*)$') def peek_test_name_match(lines: LineStream, test: Test) -> bool: """ @@ -379,6 +379,8 @@ def peek_test_name_match(lines: LineStream, test: Test) -> bool: if not match: return False name = match.group(4) + if not name: + return False return name == test.name def parse_test_result(lines: LineStream, test: Test, @@ -416,7 +418,7 @@ def parse_test_result(lines: LineStream, test: Test, # Set name of test object if skip_match: - test.name = skip_match.group(4) + test.name = skip_match.group(4) or skip_match.group(5) else: test.name = match.group(4) diff --git a/tools/testing/kunit/test_data/test_is_test_passed-kselftest.log b/tools/testing/kunit/test_data/test_is_test_passed-kselftest.log index 65d3f27feaf22a3f47ed831c4c24f6f11c625a92..30d9ef18bcec177067288d5242771236f29b7d56 100644 --- a/tools/testing/kunit/test_data/test_is_test_passed-kselftest.log +++ b/tools/testing/kunit/test_data/test_is_test_passed-kselftest.log @@ -1,5 +1,5 @@ TAP version 13 -1..2 +1..3 # selftests: membarrier: membarrier_test_single_thread # TAP version 13 # 1..2 @@ -12,3 +12,4 @@ ok 1 selftests: membarrier: membarrier_test_single_thread # ok 1 sys_membarrier available # ok 2 sys membarrier invalid command test: command = -1, flags = 0, errno = 22. Failed as expected ok 2 selftests: membarrier: membarrier_test_multi_thread +ok 3 # SKIP selftests: membarrier: membarrier_test_multi_thread --- base-commit: 8f5ae30d69d7543eee0d70083daf4de8fe15d585 change-id: 20250813-kunit-kselftesth-skip-e289becd9746 Best regards, -- Thomas Weißschuh <thomas.weissschuh(a)linutronix.de>

2 months, 3 weeks

1
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[PATCH] kunit: Always descend into kunit directory during build

by Thomas Weißschuh

For kbuild to properly clean up these build artifacts in the subdirectory, even after CONFIG_KUNIT changed do disabled, the directory needs to be processed always. Pushing the special logic for hook.o into the kunit Makefile also makes the logic easier to understand. Signed-off-by: Thomas Weißschuh <thomas.weissschuh(a)linutronix.de> Reviewed-by: David Gow <davidgow(a)google.com> --- This patch was originally part of my series "kunit: Introduce UAPI testing framework" [0], but that isn't going anywhere right now and the patch is useful on its own. Changes to the original series: * Make the commit message more general, the same issue affects all build artifacts. [0] https://lore.kernel.org/lkml/20250717-kunit-kselftests-v5-0-442b711cde2e@li… --- lib/Makefile | 4 ---- lib/kunit/Makefile | 2 +- 2 files changed, 1 insertion(+), 5 deletions(-) diff --git a/lib/Makefile b/lib/Makefile index 392ff808c9b90210849e397356d1aa435a47bd07..15a03f4c16e2cd6c75297005e71fa2108c1f41f2 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -109,11 +109,7 @@ test_fpu-y := test_fpu_glue.o test_fpu_impl.o CFLAGS_test_fpu_impl.o += $(CC_FLAGS_FPU) CFLAGS_REMOVE_test_fpu_impl.o += $(CC_FLAGS_NO_FPU) -# Some KUnit files (hooks.o) need to be built-in even when KUnit is a module, -# so we can't just use obj-$(CONFIG_KUNIT). -ifdef CONFIG_KUNIT obj-y += kunit/ -endif ifeq ($(CONFIG_DEBUG_KOBJECT),y) CFLAGS_kobject.o += -DDEBUG diff --git a/lib/kunit/Makefile b/lib/kunit/Makefile index 5aa51978e456ab3bb60c12071a26cf2bdcb1b508..656f1fa35abcc635e67d5b4cb1bc586b48415ac5 100644 --- a/lib/kunit/Makefile +++ b/lib/kunit/Makefile @@ -17,7 +17,7 @@ kunit-objs += debugfs.o endif # KUnit 'hooks' are built-in even when KUnit is built as a module. -obj-y += hooks.o +obj-$(if $(CONFIG_KUNIT),y) += hooks.o obj-$(CONFIG_KUNIT_TEST) += kunit-test.o obj-$(CONFIG_KUNIT_TEST) += platform-test.o --- base-commit: 8f5ae30d69d7543eee0d70083daf4de8fe15d585 change-id: 20250813-kunit-always-descend-39e502a8b2b9 Best regards, -- Thomas Weißschuh <thomas.weissschuh(a)linutronix.de>

2 months, 3 weeks

1
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[PATCH RFC V10 0/7] Add NUMA mempolicy support for KVM guest-memfd

by Shivank Garg

This series introduces NUMA-aware memory placement support for KVM guests with guest_memfd memory backends. It builds upon Fuad Tabba's work (V17) that enabled host-mapping for guest_memfd memory [1]. == Background == KVM's guest-memfd memory backend currently lacks support for NUMA policy enforcement, causing guest memory allocations to be distributed across host nodes according to kernel's default behavior, irrespective of any policy specified by the VMM. This limitation arises because conventional userspace NUMA control mechanisms like mbind(2) don't work since the memory isn't directly mapped to userspace when allocations occur. Fuad's work [1] provides the necessary mmap capability, and this series leverages it to enable mbind(2). == Implementation == This series implements proper NUMA policy support for guest-memfd by: 1. Adding mempolicy-aware allocation APIs to the filemap layer. 2. Introducing custom inodes (via a dedicated slab-allocated inode cache, kvm_gmem_inode_info) to store NUMA policy and metadata for guest memory. 3. Implementing get/set_policy vm_ops in guest_memfd to support NUMA policy. With these changes, VMMs can now control guest memory placement by mapping guest_memfd file descriptor and using mbind(2) to specify: - Policy modes: default, bind, interleave, or preferred - Host NUMA nodes: List of target nodes for memory allocation These Policies affect only future allocations and do not migrate existing memory. This matches mbind(2)'s default behavior which affects only new allocations unless overridden with MPOL_MF_MOVE/MPOL_MF_MOVE_ALL flags (Not supported for guest_memfd as it is unmovable by design). == Upstream Plan == Phased approach as per David's guest_memfd extension overview [2] and community calls [3]: Phase 1 (this series): 1. Focuses on shared guest_memfd support (non-CoCo VMs). 2. Builds on Fuad's host-mapping work. Phase2 (future work): 1. NUMA support for private guest_memfd (CoCo VMs). 2. Depends on SNP in-place conversion support [4]. This series provides a clean integration path for NUMA-aware memory management for guest_memfd and lays the groundwork for future confidential computing NUMA capabilities. Please review and provide feedback! Thanks, Shivank == Changelog == - v1,v2: Extended the KVM_CREATE_GUEST_MEMFD IOCTL to pass mempolicy. - v3: Introduced fbind() syscall for VMM memory-placement configuration. - v4-v6: Current approach using shared_policy support and vm_ops (based on suggestions from David [5] and guest_memfd bi-weekly upstream call discussion [6]). - v7: Use inodes to store NUMA policy instead of file [7]. - v8: Rebase on top of Fuad's V12: Host mmaping for guest_memfd memory. - v9: Rebase on top of Fuad's V13 and incorporate review comments - V10: Rebase on top of Fuad's V17. Use latest guest_memfd inode patch from Ackerley (with David's review comments). Use newer kmem_cache_create() API variant with arg parameter (Vlastimil) [1] https://lore.kernel.org/all/20250729225455.670324-1-seanjc@google.com [2] https://lore.kernel.org/all/c1c9591d-218a-495c-957b-ba356c8f8e09@redhat.com [3] https://docs.google.com/document/d/1M6766BzdY1Lhk7LiR5IqVR8B8mG3cr-cxTxOrAo… [4] https://lore.kernel.org/all/20250613005400.3694904-1-michael.roth@amd.com [5] https://lore.kernel.org/all/6fbef654-36e2-4be5-906e-2a648a845278@redhat.com [6] https://lore.kernel.org/all/2b77e055-98ac-43a1-a7ad-9f9065d7f38f@amd.com [7] https://lore.kernel.org/all/diqzbjumm167.fsf@ackerleytng-ctop.c.googlers.com Ackerley Tng (1): KVM: guest_memfd: Use guest mem inodes instead of anonymous inodes Matthew Wilcox (Oracle) (2): mm/filemap: Add NUMA mempolicy support to filemap_alloc_folio() mm/filemap: Extend __filemap_get_folio() to support NUMA memory policies Shivank Garg (4): mm/mempolicy: Export memory policy symbols KVM: guest_memfd: Add slab-allocated inode cache KVM: guest_memfd: Enforce NUMA mempolicy using shared policy KVM: guest_memfd: selftests: Add tests for mmap and NUMA policy support fs/bcachefs/fs-io-buffered.c | 2 +- fs/btrfs/compression.c | 4 +- fs/btrfs/verity.c | 2 +- fs/erofs/zdata.c | 2 +- fs/f2fs/compress.c | 2 +- include/linux/pagemap.h | 18 +- include/uapi/linux/magic.h | 1 + mm/filemap.c | 23 +- mm/mempolicy.c | 6 + mm/readahead.c | 2 +- tools/testing/selftests/kvm/Makefile.kvm | 1 + .../testing/selftests/kvm/guest_memfd_test.c | 121 ++++++++ virt/kvm/guest_memfd.c | 260 ++++++++++++++++-- virt/kvm/kvm_main.c | 7 +- virt/kvm/kvm_mm.h | 9 +- 15 files changed, 410 insertions(+), 50 deletions(-) -- 2.43.0

2 months, 3 weeks

5
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[PATCH] selftests/damon: fix damon selftests by installing _common.sh

by Alexandre Ghiti

_common.sh was recently introduced but is not installed and then triggers an error when trying to run the damon selftests: selftests: damon: sysfs.sh ./sysfs.sh: line 4: _common.sh: No such file or directory Install this file to avoid this error. Fixes: 511914506d19 ("selftests/damon: introduce _common.sh to host shared function") Signed-off-by: Alexandre Ghiti <alexghiti(a)rivosinc.com> --- tools/testing/selftests/damon/Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/tools/testing/selftests/damon/Makefile b/tools/testing/selftests/damon/Makefile index 5b230deb19e8ee6cee56eb8f18c35e12f331e8b7..ddc69e8bde2905ff1c461a08f2ad008e6b28ac87 100644 --- a/tools/testing/selftests/damon/Makefile +++ b/tools/testing/selftests/damon/Makefile @@ -4,6 +4,7 @@ TEST_GEN_FILES += access_memory access_memory_even TEST_FILES = _damon_sysfs.py +TEST_FILES += _common.sh # functionality tests TEST_PROGS += sysfs.sh --- base-commit: 2754d549af31f8f029f02d02cd8e574676229b3d change-id: 20250812-alex-fixes_manual-aed3ef75dd83 Best regards, -- Alexandre Ghiti <alexghiti(a)rivosinc.com>

2 months, 3 weeks

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