diff mbox series

[bpf-next,v3,5/6] riscv, bpf: Optimize sign-extention mov insns with Zbb support

Message ID 20240115125427.2914015-6-pulehui@huawei.com (mailing list archive)
State Superseded
Delegated to: BPF
Headers show
Series Zbb support and code simplification for RV64 JIT | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for bpf-next
netdev/ynl success SINGLE THREAD; Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 8 this patch: 8
netdev/cc_maintainers success CCed 0 of 0 maintainers
netdev/build_clang success Errors and warnings before: 8 this patch: 8
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 8 this patch: 8
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 40 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Pu Lehui Jan. 15, 2024, 12:54 p.m. UTC 
Add 8-bit and 16-bit sign-extention wraper with Zbb support to optimize
sign-extension mov instructions.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
---
 arch/riscv/net/bpf_jit.h        | 22 ++++++++++++++++++++++
 arch/riscv/net/bpf_jit_comp64.c |  5 +++--
 2 files changed, 25 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/arch/riscv/net/bpf_jit.h b/arch/riscv/net/bpf_jit.h
index 51f6d214086f..b00c5c0591d2 100644
--- a/arch/riscv/net/bpf_jit.h
+++ b/arch/riscv/net/bpf_jit.h
@@ -1119,6 +1119,28 @@  static inline void emit_subw(u8 rd, u8 rs1, u8 rs2, struct rv_jit_context *ctx)
 		emit(rv_subw(rd, rs1, rs2), ctx);
 }
 
+static inline void emit_sextb(u8 rd, u8 rs, struct rv_jit_context *ctx)
+{
+	if (rvzbb_enabled()) {
+		emit(rvzbb_sextb(rd, rs), ctx);
+		return;
+	}
+
+	emit_slli(rd, rs, 56, ctx);
+	emit_srai(rd, rd, 56, ctx);
+}
+
+static inline void emit_sexth(u8 rd, u8 rs, struct rv_jit_context *ctx)
+{
+	if (rvzbb_enabled()) {
+		emit(rvzbb_sexth(rd, rs), ctx);
+		return;
+	}
+
+	emit_slli(rd, rs, 48, ctx);
+	emit_srai(rd, rd, 48, ctx);
+}
+
 static inline void emit_sextw(u8 rd, u8 rs, struct rv_jit_context *ctx)
 {
 	emit_addiw(rd, rs, 0, ctx);
diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c
index d90784674677..18bbf8122eb3 100644
--- a/arch/riscv/net/bpf_jit_comp64.c
+++ b/arch/riscv/net/bpf_jit_comp64.c
@@ -1073,9 +1073,10 @@  int bpf_jit_emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx,
 			emit_mv(rd, rs, ctx);
 			break;
 		case 8:
+			emit_sextb(rd, rs, ctx);
+			break;
 		case 16:
-			emit_slli(RV_REG_T1, rs, 64 - insn->off, ctx);
-			emit_srai(rd, RV_REG_T1, 64 - insn->off, ctx);
+			emit_sexth(rd, rs, ctx);
 			break;
 		case 32:
 			emit_sextw(rd, rs, ctx);