From 4d9c5c53ac99e4cb5d031897863203d7817b36e0 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Mon, 20 Jul 2015 20:34:19 -0700 Subject: [PATCH] test_bpf: add bpf_skb_vlan_push/pop() tests improve accuracy of timing in test_bpf and add two stress tests: - {skb->data[0], get_smp_processor_id} repeated 2k times - {skb->data[0], vlan_push} x 68 followed by {skb->data[0], vlan_pop} x 68 1st test is useful to test performance of JIT implementation of BPF_LD_ABS together with BPF_CALL instructions. 2nd test is stressing skb_vlan_push/pop logic together with skb->data access via BPF_LD_ABS insn which checks that re-caching of skb->data is done correctly. In order to call bpf_skb_vlan_push() from test_bpf.ko have to add three export_symbol_gpl. Signed-off-by: Alexei Starovoitov Signed-off-by: David S. Miller --- kernel/bpf/core.c | 1 + lib/test_bpf.c | 98 +++++++++++++++++++++++++++++++++++++++++++++-- net/core/filter.c | 2 + 3 files changed, 98 insertions(+), 3 deletions(-) diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index bf38f5e8196c..fafa74161445 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -177,6 +177,7 @@ noinline u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) { return 0; } +EXPORT_SYMBOL_GPL(__bpf_call_base); /** * __bpf_prog_run - run eBPF program on a given context diff --git a/lib/test_bpf.c b/lib/test_bpf.c index 9198f28a5528..8b5e66f008b0 100644 --- a/lib/test_bpf.c +++ b/lib/test_bpf.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -355,6 +356,81 @@ static int bpf_fill_ja(struct bpf_test *self) return __bpf_fill_ja(self, 12, 9); } +static int bpf_fill_ld_abs_get_processor_id(struct bpf_test *self) +{ + unsigned int len = BPF_MAXINSNS; + struct sock_filter *insn; + int i; + + insn = kmalloc_array(len, sizeof(*insn), GFP_KERNEL); + if (!insn) + return -ENOMEM; + + for (i = 0; i < len - 1; i += 2) { + insn[i] = __BPF_STMT(BPF_LD | BPF_B | BPF_ABS, 0); + insn[i + 1] = __BPF_STMT(BPF_LD | BPF_W | BPF_ABS, + SKF_AD_OFF + SKF_AD_CPU); + } + + insn[len - 1] = __BPF_STMT(BPF_RET | BPF_K, 0xbee); + + self->u.ptr.insns = insn; + self->u.ptr.len = len; + + return 0; +} + +#define PUSH_CNT 68 +/* test: {skb->data[0], vlan_push} x 68 + {skb->data[0], vlan_pop} x 68 */ +static int bpf_fill_ld_abs_vlan_push_pop(struct bpf_test *self) +{ + unsigned int len = BPF_MAXINSNS; + struct bpf_insn *insn; + int i = 0, j, k = 0; + + insn = kmalloc_array(len, sizeof(*insn), GFP_KERNEL); + if (!insn) + return -ENOMEM; + + insn[i++] = BPF_MOV64_REG(R6, R1); +loop: + for (j = 0; j < PUSH_CNT; j++) { + insn[i++] = BPF_LD_ABS(BPF_B, 0); + insn[i] = BPF_JMP_IMM(BPF_JNE, R0, 0x34, len - i - 2); + i++; + insn[i++] = BPF_MOV64_REG(R1, R6); + insn[i++] = BPF_MOV64_IMM(R2, 1); + insn[i++] = BPF_MOV64_IMM(R3, 2); + insn[i++] = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, + bpf_skb_vlan_push_proto.func - __bpf_call_base); + insn[i] = BPF_JMP_IMM(BPF_JNE, R0, 0, len - i - 2); + i++; + } + + for (j = 0; j < PUSH_CNT; j++) { + insn[i++] = BPF_LD_ABS(BPF_B, 0); + insn[i] = BPF_JMP_IMM(BPF_JNE, R0, 0x34, len - i - 2); + i++; + insn[i++] = BPF_MOV64_REG(R1, R6); + insn[i++] = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, + bpf_skb_vlan_pop_proto.func - __bpf_call_base); + insn[i] = BPF_JMP_IMM(BPF_JNE, R0, 0, len - i - 2); + i++; + } + if (++k < 5) + goto loop; + + for (; i < len - 1; i++) + insn[i] = BPF_ALU32_IMM(BPF_MOV, R0, 0xbef); + + insn[len - 1] = BPF_EXIT_INSN(); + + self->u.ptr.insns = insn; + self->u.ptr.len = len; + + return 0; +} + static struct bpf_test tests[] = { { "TAX", @@ -4398,6 +4474,22 @@ static struct bpf_test tests[] = { { { 0, 0xababcbac } }, .fill_helper = bpf_fill_maxinsns11, }, + { + "BPF_MAXINSNS: ld_abs+get_processor_id", + { }, + CLASSIC, + { }, + { { 1, 0xbee } }, + .fill_helper = bpf_fill_ld_abs_get_processor_id, + }, + { + "BPF_MAXINSNS: ld_abs+vlan_push/pop", + { }, + INTERNAL, + { 0x34 }, + { { 1, 0xbef } }, + .fill_helper = bpf_fill_ld_abs_vlan_push_pop, + }, }; static struct net_device dev; @@ -4551,14 +4643,14 @@ static int __run_one(const struct bpf_prog *fp, const void *data, u64 start, finish; int ret = 0, i; - start = ktime_to_us(ktime_get()); + start = ktime_get_ns(); for (i = 0; i < runs; i++) ret = BPF_PROG_RUN(fp, data); - finish = ktime_to_us(ktime_get()); + finish = ktime_get_ns(); - *duration = (finish - start) * 1000ULL; + *duration = finish - start; do_div(*duration, runs); return ret; diff --git a/net/core/filter.c b/net/core/filter.c index 50338071fac4..786722a9c6f2 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -1457,6 +1457,7 @@ const struct bpf_func_proto bpf_skb_vlan_push_proto = { .arg2_type = ARG_ANYTHING, .arg3_type = ARG_ANYTHING, }; +EXPORT_SYMBOL_GPL(bpf_skb_vlan_push_proto); static u64 bpf_skb_vlan_pop(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) { @@ -1471,6 +1472,7 @@ const struct bpf_func_proto bpf_skb_vlan_pop_proto = { .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, }; +EXPORT_SYMBOL_GPL(bpf_skb_vlan_pop_proto); bool bpf_helper_changes_skb_data(void *func) { -- 2.20.1