On Tue, Jul 2, 2019 at 8:40 AM Ilya Leoshkevich <iii@xxxxxxxxxxxxx> wrote:
>
> Use PT_REGS_RC(ctx) instead of ctx->rax, which is not present on s390.
>
> Pass -D__TARGET_ARCH_$(ARCH) to selftests in order to choose a proper
> PT_REGS_RC variant.
>
> Fix s930 -> s390 typo.
>
> On s390, provide the forward declaration of struct pt_regs and cast it
> to user_pt_regs in PT_REGS_* macros. This is necessary, because instead
> of the full struct pt_regs, s390 exposes only its first field
> user_pt_regs to userspace, and bpf_helpers.h is used with both userspace
> (in selftests) and kernel (in samples) headers.
>
> On x86, provide userspace versions of PT_REGS_* macros. Unlike s390, x86
> provides struct pt_regs to both userspace and kernel, however, with
> different field names.
>
> Signed-off-by: Ilya Leoshkevich <iii@xxxxxxxxxxxxx>
Acked-by: Yonghong Song <yhs@xxxxxx>
> ---
> tools/testing/selftests/bpf/Makefile | 4 +-
> tools/testing/selftests/bpf/bpf_helpers.h | 46 +++++++++++++++--------
> tools/testing/selftests/bpf/progs/loop1.c | 2 +-
> tools/testing/selftests/bpf/progs/loop2.c | 2 +-
> tools/testing/selftests/bpf/progs/loop3.c | 2 +-
> 5 files changed, 37 insertions(+), 19 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
> index d60fee59fbd1..599b320bef65 100644
> --- a/tools/testing/selftests/bpf/Makefile
> +++ b/tools/testing/selftests/bpf/Makefile
> @@ -1,5 +1,6 @@
> # SPDX-License-Identifier: GPL-2.0
> include ../../../../scripts/Kbuild.include
> +include ../../../scripts/Makefile.arch
>
> LIBDIR := ../../../lib
> BPFDIR := $(LIBDIR)/bpf
> @@ -138,7 +139,8 @@ CLANG_SYS_INCLUDES := $(shell $(CLANG) -v -E - </dev/null 2>&1 \
>
> CLANG_FLAGS = -I. -I./include/uapi -I../../../include/uapi \
> $(CLANG_SYS_INCLUDES) \
> - -Wno-compare-distinct-pointer-types
> + -Wno-compare-distinct-pointer-types \
> + -D__TARGET_ARCH_$(ARCH)
>
> $(OUTPUT)/test_l4lb_noinline.o: CLANG_FLAGS += -fno-inline
> $(OUTPUT)/test_xdp_noinline.o: CLANG_FLAGS += -fno-inline
> diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
> index 1a5b1accf091..faf86d83301a 100644
> --- a/tools/testing/selftests/bpf/bpf_helpers.h
> +++ b/tools/testing/selftests/bpf/bpf_helpers.h
> @@ -312,8 +312,8 @@ static int (*bpf_skb_adjust_room)(void *ctx, __s32 len_diff, __u32 mode,
> #if defined(__TARGET_ARCH_x86)
> #define bpf_target_x86
> #define bpf_target_defined
> -#elif defined(__TARGET_ARCH_s930x)
> - #define bpf_target_s930x
> +#elif defined(__TARGET_ARCH_s390)
> + #define bpf_target_s390
> #define bpf_target_defined
> #elif defined(__TARGET_ARCH_arm)
> #define bpf_target_arm
> @@ -338,8 +338,8 @@ static int (*bpf_skb_adjust_room)(void *ctx, __s32 len_diff, __u32 mode,
> #ifndef bpf_target_defined
> #if defined(__x86_64__)
> #define bpf_target_x86
> -#elif defined(__s390x__)
> - #define bpf_target_s930x
> +#elif defined(__s390__)
> + #define bpf_target_s390
> #elif defined(__arm__)
> #define bpf_target_arm
> #elif defined(__aarch64__)
> @@ -355,6 +355,7 @@ static int (*bpf_skb_adjust_room)(void *ctx, __s32 len_diff, __u32 mode,
>
> #if defined(bpf_target_x86)
>
> +#ifdef __KERNEL__
> #define PT_REGS_PARM1(x) ((x)->di)
> #define PT_REGS_PARM2(x) ((x)->si)
> #define PT_REGS_PARM3(x) ((x)->dx)
> @@ -365,19 +366,34 @@ static int (*bpf_skb_adjust_room)(void *ctx, __s32 len_diff, __u32 mode,
> #define PT_REGS_RC(x) ((x)->ax)
> #define PT_REGS_SP(x) ((x)->sp)
> #define PT_REGS_IP(x) ((x)->ip)
> +#else
> +#define PT_REGS_PARM1(x) ((x)->rdi)
> +#define PT_REGS_PARM2(x) ((x)->rsi)
> +#define PT_REGS_PARM3(x) ((x)->rdx)
> +#define PT_REGS_PARM4(x) ((x)->rcx)
> +#define PT_REGS_PARM5(x) ((x)->r8)
> +#define PT_REGS_RET(x) ((x)->rsp)
> +#define PT_REGS_FP(x) ((x)->rbp)
> +#define PT_REGS_RC(x) ((x)->rax)
> +#define PT_REGS_SP(x) ((x)->rsp)
> +#define PT_REGS_IP(x) ((x)->rip)
> +#endif
>
> -#elif defined(bpf_target_s390x)
> +#elif defined(bpf_target_s390)
>
> -#define PT_REGS_PARM1(x) ((x)->gprs[2])
> -#define PT_REGS_PARM2(x) ((x)->gprs[3])
> -#define PT_REGS_PARM3(x) ((x)->gprs[4])
> -#define PT_REGS_PARM4(x) ((x)->gprs[5])
> -#define PT_REGS_PARM5(x) ((x)->gprs[6])
> -#define PT_REGS_RET(x) ((x)->gprs[14])
> -#define PT_REGS_FP(x) ((x)->gprs[11]) /* Works only with CONFIG_FRAME_POINTER */
> -#define PT_REGS_RC(x) ((x)->gprs[2])
> -#define PT_REGS_SP(x) ((x)->gprs[15])
> -#define PT_REGS_IP(x) ((x)->psw.addr)
> +/* s390 provides user_pt_regs instead of struct pt_regs to userspace */
> +struct pt_regs;
> +#define PT_REGS_PARM1(x) (((const volatile user_pt_regs *)(x))->gprs[2])
> +#define PT_REGS_PARM2(x) (((const volatile user_pt_regs *)(x))->gprs[3])
> +#define PT_REGS_PARM3(x) (((const volatile user_pt_regs *)(x))->gprs[4])
> +#define PT_REGS_PARM4(x) (((const volatile user_pt_regs *)(x))->gprs[5])
> +#define PT_REGS_PARM5(x) (((const volatile user_pt_regs *)(x))->gprs[6])
> +#define PT_REGS_RET(x) (((const volatile user_pt_regs *)(x))->gprs[14])
> +/* Works only with CONFIG_FRAME_POINTER */
> +#define PT_REGS_FP(x) (((const volatile user_pt_regs *)(x))->gprs[11])
> +#define PT_REGS_RC(x) (((const volatile user_pt_regs *)(x))->gprs[2])
> +#define PT_REGS_SP(x) (((const volatile user_pt_regs *)(x))->gprs[15])
> +#define PT_REGS_IP(x) (((const volatile user_pt_regs *)(x))->psw.addr)
>
> #elif defined(bpf_target_arm)
>
> diff --git a/tools/testing/selftests/bpf/progs/loop1.c b/tools/testing/selftests/bpf/progs/loop1.c
> index dea395af9ea9..7cdb7f878310 100644
> --- a/tools/testing/selftests/bpf/progs/loop1.c
> +++ b/tools/testing/selftests/bpf/progs/loop1.c
> @@ -18,7 +18,7 @@ int nested_loops(volatile struct pt_regs* ctx)
> for (j = 0; j < 300; j++)
> for (i = 0; i < j; i++) {
> if (j & 1)
> - m = ctx->rax;
> + m = PT_REGS_RC(ctx);
> else
> m = j;
> sum += i * m;
> diff --git a/tools/testing/selftests/bpf/progs/loop2.c b/tools/testing/selftests/bpf/progs/loop2.c
> index 0637bd8e8bcf..9b2f808a2863 100644
> --- a/tools/testing/selftests/bpf/progs/loop2.c
> +++ b/tools/testing/selftests/bpf/progs/loop2.c
> @@ -16,7 +16,7 @@ int while_true(volatile struct pt_regs* ctx)
> int i = 0;
>
> while (true) {
> - if (ctx->rax & 1)
> + if (PT_REGS_RC(ctx) & 1)
> i += 3;
> else
> i += 7;
> diff --git a/tools/testing/selftests/bpf/progs/loop3.c b/tools/testing/selftests/bpf/progs/loop3.c
> index 30a0f6cba080..d727657d51e2 100644
> --- a/tools/testing/selftests/bpf/progs/loop3.c
> +++ b/tools/testing/selftests/bpf/progs/loop3.c
> @@ -16,7 +16,7 @@ int while_true(volatile struct pt_regs* ctx)
> __u64 i = 0, sum = 0;
> do {
> i++;
> - sum += ctx->rax;
> + sum += PT_REGS_RC(ctx);
> } while (i < 0x100000000ULL);
> return sum;
> }
> --
> 2.21.0
>
