All of lore.kernel.org
 help / color / mirror / Atom feed
From: Johan Almbladh <johan.almbladh@anyfinetworks.com>
To: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org,
	iii@linux.ibm.com
Cc: kafai@fb.com, songliubraving@fb.com, yhs@fb.com,
	john.fastabend@gmail.com, kpsingh@kernel.org,
	netdev@vger.kernel.org, bpf@vger.kernel.org,
	Johan Almbladh <johan.almbladh@anyfinetworks.com>
Subject: [PATCH bpf-next 03/13] bpf/tests: Add exhaustive tests of ALU shift values
Date: Thu,  2 Sep 2021 20:52:19 +0200	[thread overview]
Message-ID: <20210902185229.1840281-4-johan.almbladh@anyfinetworks.com> (raw)
In-Reply-To: <20210902185229.1840281-1-johan.almbladh@anyfinetworks.com>

This patch adds a set of tests for ALU64 and ALU32 shift operations to
verify correctness for all possible values of the shift value. Mainly
intended for JIT testing.

Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
---
 lib/test_bpf.c | 257 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 257 insertions(+)

diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index f0651dc6450b..69f8d4c1df33 100644
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -497,6 +497,165 @@ static int bpf_fill_long_jmp(struct bpf_test *self)
 	return 0;
 }
 
+static int __bpf_ld_imm64(struct bpf_insn insns[2], u8 reg, s64 imm64)
+{
+	struct bpf_insn tmp[] = {BPF_LD_IMM64(reg, imm64)};
+
+	memcpy(insns, tmp, sizeof(tmp));
+	return 2;
+}
+
+/* Test an ALU shift operation for all valid shift values */
+static int __bpf_fill_alu_shift(struct bpf_test *self, u8 op,
+				u8 mode, bool alu32)
+{
+	static const s64 regs[] = {
+		0x0123456789abcdefLL, /* dword > 0, word < 0 */
+		0xfedcba9876543210LL, /* dowrd < 0, word > 0 */
+		0xfedcba0198765432LL, /* dowrd < 0, word < 0 */
+		0x0123458967abcdefLL, /* dword > 0, word > 0 */
+	};
+	int bits = alu32 ? 32 : 64;
+	int len = (2 + 8 * bits) * ARRAY_SIZE(regs) + 2;
+	struct bpf_insn *insn;
+	int imm, k;
+	int i = 0;
+
+	insn = kmalloc_array(len, sizeof(*insn), GFP_KERNEL);
+	if (!insn)
+		return -ENOMEM;
+
+	for (k = 0; k < ARRAY_SIZE(regs); k++) {
+		s64 reg = regs[k];
+
+		i += __bpf_ld_imm64(&insn[i], R3, reg);
+
+		for (imm = 0; imm < bits; imm++) {
+			u64 val;
+
+			/* Perform operation */
+			insn[i++] = BPF_ALU64_REG(BPF_MOV, R1, R3);
+			insn[i++] = BPF_ALU64_IMM(BPF_MOV, R2, imm);
+			if (alu32) {
+				if (mode == BPF_K)
+					insn[i++] = BPF_ALU32_IMM(op, R1, imm);
+				else
+					insn[i++] = BPF_ALU32_REG(op, R1, R2);
+				switch (op) {
+				case BPF_LSH:
+					val = (u32)reg << imm;
+					break;
+				case BPF_RSH:
+					val = (u32)reg >> imm;
+					break;
+				case BPF_ARSH:
+					val = (u32)reg >> imm;
+					if (imm > 0 && (reg & 0x80000000))
+						val |= ~(u32)0 << (32 - imm);
+					break;
+				}
+			} else {
+				if (mode == BPF_K)
+					insn[i++] = BPF_ALU64_IMM(op, R1, imm);
+				else
+					insn[i++] = BPF_ALU64_REG(op, R1, R2);
+				switch (op) {
+				case BPF_LSH:
+					val = (u64)reg << imm;
+					break;
+				case BPF_RSH:
+					val = (u64)reg >> imm;
+					break;
+				case BPF_ARSH:
+					val = (u64)reg >> imm;
+					if (imm > 0 && reg < 0)
+						val |= ~(u64)0 << (64 - imm);
+					break;
+				}
+			}
+
+			/* Load reference */
+			i += __bpf_ld_imm64(&insn[i], R4, val);
+
+			/* For diagnostic purposes */
+			insn[i++] = BPF_ALU64_IMM(BPF_MOV, R0, i);
+
+			/* Check result */
+			insn[i++] = BPF_JMP_REG(BPF_JEQ, R1, R4, 1);
+			insn[i++] = BPF_EXIT_INSN();
+		}
+	}
+
+	insn[i++] = BPF_ALU64_IMM(BPF_MOV, R0, 1);
+	insn[i++] = BPF_EXIT_INSN();
+
+	self->u.ptr.insns = insn;
+	self->u.ptr.len = len;
+	BUG_ON(i > len);
+
+	return 0;
+}
+
+static int bpf_fill_alu_lsh_imm(struct bpf_test *self)
+{
+	return __bpf_fill_alu_shift(self, BPF_LSH, BPF_K, false);
+}
+
+static int bpf_fill_alu_rsh_imm(struct bpf_test *self)
+{
+	return __bpf_fill_alu_shift(self, BPF_RSH, BPF_K, false);
+}
+
+static int bpf_fill_alu_arsh_imm(struct bpf_test *self)
+{
+	return __bpf_fill_alu_shift(self, BPF_ARSH, BPF_K, false);
+}
+
+static int bpf_fill_alu_lsh_reg(struct bpf_test *self)
+{
+	return __bpf_fill_alu_shift(self, BPF_LSH, BPF_X, false);
+}
+
+static int bpf_fill_alu_rsh_reg(struct bpf_test *self)
+{
+	return __bpf_fill_alu_shift(self, BPF_RSH, BPF_X, false);
+}
+
+static int bpf_fill_alu_arsh_reg(struct bpf_test *self)
+{
+	return __bpf_fill_alu_shift(self, BPF_ARSH, BPF_X, false);
+}
+
+static int bpf_fill_alu32_lsh_imm(struct bpf_test *self)
+{
+	return __bpf_fill_alu_shift(self, BPF_LSH, BPF_K, true);
+}
+
+static int bpf_fill_alu32_rsh_imm(struct bpf_test *self)
+{
+	return __bpf_fill_alu_shift(self, BPF_RSH, BPF_K, true);
+}
+
+static int bpf_fill_alu32_arsh_imm(struct bpf_test *self)
+{
+	return __bpf_fill_alu_shift(self, BPF_ARSH, BPF_K, true);
+}
+
+static int bpf_fill_alu32_lsh_reg(struct bpf_test *self)
+{
+	return __bpf_fill_alu_shift(self, BPF_LSH, BPF_X, true);
+}
+
+static int bpf_fill_alu32_rsh_reg(struct bpf_test *self)
+{
+	return __bpf_fill_alu_shift(self, BPF_RSH, BPF_X, true);
+}
+
+static int bpf_fill_alu32_arsh_reg(struct bpf_test *self)
+{
+	return __bpf_fill_alu_shift(self, BPF_ARSH, BPF_X, true);
+}
+
 static struct bpf_test tests[] = {
 	{
 		"TAX",
@@ -8414,6 +8573,104 @@ static struct bpf_test tests[] = {
 		{},
 		{ { 0, 2 } },
 	},
+	/* Exhaustive test of ALU64 shift operations */
+	{
+		"ALU64_LSH_K: all shift values",
+		{ },
+		INTERNAL | FLAG_NO_DATA,
+		{ },
+		{ { 0, 1 } },
+		.fill_helper = bpf_fill_alu_lsh_imm,
+	},
+	{
+		"ALU64_RSH_K: all shift values",
+		{ },
+		INTERNAL | FLAG_NO_DATA,
+		{ },
+		{ { 0, 1 } },
+		.fill_helper = bpf_fill_alu_rsh_imm,
+	},
+	{
+		"ALU64_ARSH_K: all shift values",
+		{ },
+		INTERNAL | FLAG_NO_DATA,
+		{ },
+		{ { 0, 1 } },
+		.fill_helper = bpf_fill_alu_arsh_imm,
+	},
+	{
+		"ALU64_LSH_X: all shift values",
+		{ },
+		INTERNAL | FLAG_NO_DATA,
+		{ },
+		{ { 0, 1 } },
+		.fill_helper = bpf_fill_alu_lsh_reg,
+	},
+	{
+		"ALU64_RSH_X: all shift values",
+		{ },
+		INTERNAL | FLAG_NO_DATA,
+		{ },
+		{ { 0, 1 } },
+		.fill_helper = bpf_fill_alu_rsh_reg,
+	},
+	{
+		"ALU64_ARSH_X: all shift values",
+		{ },
+		INTERNAL | FLAG_NO_DATA,
+		{ },
+		{ { 0, 1 } },
+		.fill_helper = bpf_fill_alu_arsh_reg,
+	},
+	/* Exhaustive test of ALU32 shift operations */
+	{
+		"ALU32_LSH_K: all shift values",
+		{ },
+		INTERNAL | FLAG_NO_DATA,
+		{ },
+		{ { 0, 1 } },
+		.fill_helper = bpf_fill_alu32_lsh_imm,
+	},
+	{
+		"ALU32_RSH_K: all shift values",
+		{ },
+		INTERNAL | FLAG_NO_DATA,
+		{ },
+		{ { 0, 1 } },
+		.fill_helper = bpf_fill_alu32_rsh_imm,
+	},
+	{
+		"ALU32_ARSH_K: all shift values",
+		{ },
+		INTERNAL | FLAG_NO_DATA,
+		{ },
+		{ { 0, 1 } },
+		.fill_helper = bpf_fill_alu32_arsh_imm,
+	},
+	{
+		"ALU32_LSH_X: all shift values",
+		{ },
+		INTERNAL | FLAG_NO_DATA,
+		{ },
+		{ { 0, 1 } },
+		.fill_helper = bpf_fill_alu32_lsh_reg,
+	},
+	{
+		"ALU32_RSH_X: all shift values",
+		{ },
+		INTERNAL | FLAG_NO_DATA,
+		{ },
+		{ { 0, 1 } },
+		.fill_helper = bpf_fill_alu32_rsh_reg,
+	},
+	{
+		"ALU32_ARSH_X: all shift values",
+		{ },
+		INTERNAL | FLAG_NO_DATA,
+		{ },
+		{ { 0, 1 } },
+		.fill_helper = bpf_fill_alu32_arsh_reg,
+	},
 };
 
 static struct net_device dev;
-- 
2.25.1


  parent reply	other threads:[~2021-09-02 18:52 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-09-02 18:52 [PATCH bpf-next 00/13] bpf/tests: Extend JIT test suite coverage Johan Almbladh
2021-09-02 18:52 ` [PATCH bpf-next 01/13] bpf/tests: Allow different number of runs per test case Johan Almbladh
2021-09-02 18:52 ` [PATCH bpf-next 02/13] bpf/tests: Reduce memory footprint of test suite Johan Almbladh
2021-09-02 18:52 ` Johan Almbladh [this message]
2021-09-03  6:39   ` [PATCH bpf-next 03/13] bpf/tests: Add exhaustive tests of ALU shift values kernel test robot
2021-09-03  6:39     ` kernel test robot
2021-09-02 18:52 ` [PATCH bpf-next 04/13] bpf/tests: Add exhaustive tests of ALU operand magnitudes Johan Almbladh
2021-09-02 18:52 ` [PATCH bpf-next 05/13] bpf/tests: Add exhaustive tests of JMP " Johan Almbladh
2021-09-02 18:52 ` [PATCH bpf-next 06/13] bpf/tests: Add staggered JMP and JMP32 tests Johan Almbladh
2021-09-03  8:22   ` Johan Almbladh
2021-09-02 18:52 ` [PATCH bpf-next 07/13] bpf/tests: Add exhaustive test of LD_IMM64 immediate magnitudes Johan Almbladh
2021-09-02 18:52 ` [PATCH bpf-next 08/13] bpf/tests: Add test case flag for verifier zero-extension Johan Almbladh
2021-09-02 18:52 ` [PATCH bpf-next 09/13] bpf/tests: Add JMP tests with small offsets Johan Almbladh
2021-09-02 18:52 ` [PATCH bpf-next 10/13] bpf/tests: Add JMP tests with degenerate conditional Johan Almbladh
2021-09-02 18:52 ` [PATCH bpf-next 11/13] bpf/tests: Expand branch conversion JIT test Johan Almbladh
2021-09-02 18:52 ` [PATCH bpf-next 12/13] bpf/tests: Add more BPF_END byte order conversion tests Johan Almbladh
2021-09-02 18:52 ` [PATCH bpf-next 13/13] bpf/tests: Add tail call limit test with external function call Johan Almbladh

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210902185229.1840281-4-johan.almbladh@anyfinetworks.com \
    --to=johan.almbladh@anyfinetworks.com \
    --cc=andrii@kernel.org \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=iii@linux.ibm.com \
    --cc=john.fastabend@gmail.com \
    --cc=kafai@fb.com \
    --cc=kpsingh@kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=songliubraving@fb.com \
    --cc=yhs@fb.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.