Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
riscv, bpf: Extract emit_st() helper
There's a lot of redundant code related to store from immediate
operations, let's extract emit_st() to make code more compact.
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/bpf/20250719091730.2660197-3-pulehui@huaweicloud.com
authored by
Pu Lehui
and committed by
Daniel Borkmann
d92c11a6
02fc01ad
+26
-109
+26
-109
arch/riscv/net/bpf_jit_comp64.c
+26
-109
arch/riscv/net/bpf_jit_comp64.c
···
577
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}
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}
579
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580
+
static int emit_st(u8 rd, s16 off, s32 imm, u8 size, struct rv_jit_context *ctx)
581
+
{
582
+
int insns_start;
583
+
584
+
emit_imm(RV_REG_T1, imm, ctx);
585
+
if (is_12b_int(off)) {
586
+
insns_start = ctx->ninsns;
587
+
emit_stx_insn(rd, off, RV_REG_T1, size, ctx);
588
+
return ctx->ninsns - insns_start;
589
+
}
590
+
591
+
emit_imm(RV_REG_T2, off, ctx);
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+
emit_add(RV_REG_T2, RV_REG_T2, rd, ctx);
593
+
insns_start = ctx->ninsns;
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+
emit_stx_insn(RV_REG_T2, 0, RV_REG_T1, size, ctx);
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+
return ctx->ninsns - insns_start;
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+
}
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+
580
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static int emit_stx(u8 rd, s16 off, u8 rs, u8 size, struct rv_jit_context *ctx)
581
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{
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int insns_start;
···
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/* ST: *(size *)(dst + off) = imm */
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case BPF_ST | BPF_MEM | BPF_B:
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-
emit_imm(RV_REG_T1, imm, ctx);
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-
if (is_12b_int(off)) {
1893
-
emit(rv_sb(rd, off, RV_REG_T1), ctx);
1894
-
break;
1895
-
}
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-
1897
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emit_imm(RV_REG_T2, off, ctx);
1898
-
emit_add(RV_REG_T2, RV_REG_T2, rd, ctx);
1899
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emit(rv_sb(RV_REG_T2, 0, RV_REG_T1), ctx);
1900
-
break;
1901
-
1902
1873
case BPF_ST | BPF_MEM | BPF_H:
1903
-
emit_imm(RV_REG_T1, imm, ctx);
1904
-
if (is_12b_int(off)) {
1905
-
emit(rv_sh(rd, off, RV_REG_T1), ctx);
1906
-
break;
1907
-
}
1908
-
1909
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emit_imm(RV_REG_T2, off, ctx);
1910
-
emit_add(RV_REG_T2, RV_REG_T2, rd, ctx);
1911
-
emit(rv_sh(RV_REG_T2, 0, RV_REG_T1), ctx);
1912
-
break;
1913
1874
case BPF_ST | BPF_MEM | BPF_W:
1914
-
emit_imm(RV_REG_T1, imm, ctx);
1915
-
if (is_12b_int(off)) {
1916
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emit_sw(rd, off, RV_REG_T1, ctx);
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-
break;
1918
-
}
1919
-
1920
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emit_imm(RV_REG_T2, off, ctx);
1921
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emit_add(RV_REG_T2, RV_REG_T2, rd, ctx);
1922
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emit_sw(RV_REG_T2, 0, RV_REG_T1, ctx);
1923
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break;
1924
1875
case BPF_ST | BPF_MEM | BPF_DW:
1925
-
emit_imm(RV_REG_T1, imm, ctx);
1926
-
if (is_12b_int(off)) {
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emit_sd(rd, off, RV_REG_T1, ctx);
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-
break;
1929
-
}
1930
-
1931
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emit_imm(RV_REG_T2, off, ctx);
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emit_add(RV_REG_T2, RV_REG_T2, rd, ctx);
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-
emit_sd(RV_REG_T2, 0, RV_REG_T1, ctx);
1934
-
break;
1935
-
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+
/* ST | PROBE_MEM32: *(size *)(dst + RV_REG_ARENA + off) = imm */
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case BPF_ST | BPF_PROBE_MEM32 | BPF_B:
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case BPF_ST | BPF_PROBE_MEM32 | BPF_H:
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case BPF_ST | BPF_PROBE_MEM32 | BPF_W:
1939
1880
case BPF_ST | BPF_PROBE_MEM32 | BPF_DW:
1940
1881
{
1941
-
int insn_len, insns_start;
1882
+
int insn_len;
1942
1883
1943
-
emit_add(RV_REG_T3, rd, RV_REG_ARENA, ctx);
1944
-
rd = RV_REG_T3;
1945
-
1946
-
/* Load imm to a register then store it */
1947
-
emit_imm(RV_REG_T1, imm, ctx);
1948
-
1949
-
switch (BPF_SIZE(code)) {
1950
-
case BPF_B:
1951
-
if (is_12b_int(off)) {
1952
-
insns_start = ctx->ninsns;
1953
-
emit(rv_sb(rd, off, RV_REG_T1), ctx);
1954
-
insn_len = ctx->ninsns - insns_start;
1955
-
break;
1956
-
}
1957
-
1958
-
emit_imm(RV_REG_T2, off, ctx);
1959
-
emit_add(RV_REG_T2, RV_REG_T2, rd, ctx);
1960
-
insns_start = ctx->ninsns;
1961
-
emit(rv_sb(RV_REG_T2, 0, RV_REG_T1), ctx);
1962
-
insn_len = ctx->ninsns - insns_start;
1963
-
break;
1964
-
case BPF_H:
1965
-
if (is_12b_int(off)) {
1966
-
insns_start = ctx->ninsns;
1967
-
emit(rv_sh(rd, off, RV_REG_T1), ctx);
1968
-
insn_len = ctx->ninsns - insns_start;
1969
-
break;
1970
-
}
1971
-
1972
-
emit_imm(RV_REG_T2, off, ctx);
1973
-
emit_add(RV_REG_T2, RV_REG_T2, rd, ctx);
1974
-
insns_start = ctx->ninsns;
1975
-
emit(rv_sh(RV_REG_T2, 0, RV_REG_T1), ctx);
1976
-
insn_len = ctx->ninsns - insns_start;
1977
-
break;
1978
-
case BPF_W:
1979
-
if (is_12b_int(off)) {
1980
-
insns_start = ctx->ninsns;
1981
-
emit_sw(rd, off, RV_REG_T1, ctx);
1982
-
insn_len = ctx->ninsns - insns_start;
1983
-
break;
1984
-
}
1985
-
1986
-
emit_imm(RV_REG_T2, off, ctx);
1987
-
emit_add(RV_REG_T2, RV_REG_T2, rd, ctx);
1988
-
insns_start = ctx->ninsns;
1989
-
emit_sw(RV_REG_T2, 0, RV_REG_T1, ctx);
1990
-
insn_len = ctx->ninsns - insns_start;
1991
-
break;
1992
-
case BPF_DW:
1993
-
if (is_12b_int(off)) {
1994
-
insns_start = ctx->ninsns;
1995
-
emit_sd(rd, off, RV_REG_T1, ctx);
1996
-
insn_len = ctx->ninsns - insns_start;
1997
-
break;
1998
-
}
1999
-
2000
-
emit_imm(RV_REG_T2, off, ctx);
2001
-
emit_add(RV_REG_T2, RV_REG_T2, rd, ctx);
2002
-
insns_start = ctx->ninsns;
2003
-
emit_sd(RV_REG_T2, 0, RV_REG_T1, ctx);
2004
-
insn_len = ctx->ninsns - insns_start;
2005
-
break;
1884
+
if (BPF_MODE(insn->code) == BPF_PROBE_MEM32) {
1885
+
emit_add(RV_REG_T3, rd, RV_REG_ARENA, ctx);
1886
+
rd = RV_REG_T3;
2006
1887
}
2007
1888
2008
-
ret = add_exception_handler(insn, ctx, REG_DONT_CLEAR_MARKER,
2009
-
insn_len);
1889
+
insn_len = emit_st(rd, off, imm, BPF_SIZE(code), ctx);
1890
+
1891
+
ret = add_exception_handler(insn, ctx, REG_DONT_CLEAR_MARKER, insn_len);
2010
1892
if (ret)
2011
1893
return ret;
2012
-
2013
1894
break;
2014
1895
}
2015
1896