diff options
| -rw-r--r-- | tools/testing/selftests/bpf/bpf_experimental.h | 69 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/progs/exceptions.c | 20 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/progs/iters_task_vma.c | 3 |
3 files changed, 80 insertions, 12 deletions
diff --git a/tools/testing/selftests/bpf/bpf_experimental.h b/tools/testing/selftests/bpf/bpf_experimental.h index 1386baf9ae4a..19ed6c941c1c 100644 --- a/tools/testing/selftests/bpf/bpf_experimental.h +++ b/tools/testing/selftests/bpf/bpf_experimental.h @@ -254,6 +254,75 @@ extern void bpf_throw(u64 cookie) __ksym; } \ }) +#define __cmp_cannot_be_signed(x) \ + __builtin_strcmp(#x, "==") == 0 || __builtin_strcmp(#x, "!=") == 0 || \ + __builtin_strcmp(#x, "&") == 0 + +#define __is_signed_type(type) (((type)(-1)) < (type)1) + +#define __bpf_cmp(LHS, OP, SIGN, PRED, RHS, DEFAULT) \ + ({ \ + __label__ l_true; \ + bool ret = DEFAULT; \ + asm volatile goto("if %[lhs] " SIGN #OP " %[rhs] goto %l[l_true]" \ + :: [lhs] "r"((short)LHS), [rhs] PRED (RHS) :: l_true); \ + ret = !DEFAULT; \ +l_true: \ + ret; \ + }) + +/* C type conversions coupled with comparison operator are tricky. + * Make sure BPF program is compiled with -Wsign-compare then + * __lhs OP __rhs below will catch the mistake. + * Be aware that we check only __lhs to figure out the sign of compare. + */ +#define _bpf_cmp(LHS, OP, RHS, NOFLIP) \ + ({ \ + typeof(LHS) __lhs = (LHS); \ + typeof(RHS) __rhs = (RHS); \ + bool ret; \ + _Static_assert(sizeof(&(LHS)), "1st argument must be an lvalue expression"); \ + (void)(__lhs OP __rhs); \ + if (__cmp_cannot_be_signed(OP) || !__is_signed_type(typeof(__lhs))) { \ + if (sizeof(__rhs) == 8) \ + ret = __bpf_cmp(__lhs, OP, "", "r", __rhs, NOFLIP); \ + else \ + ret = __bpf_cmp(__lhs, OP, "", "i", __rhs, NOFLIP); \ + } else { \ + if (sizeof(__rhs) == 8) \ + ret = __bpf_cmp(__lhs, OP, "s", "r", __rhs, NOFLIP); \ + else \ + ret = __bpf_cmp(__lhs, OP, "s", "i", __rhs, NOFLIP); \ + } \ + ret; \ + }) + +#ifndef bpf_cmp_unlikely +#define bpf_cmp_unlikely(LHS, OP, RHS) _bpf_cmp(LHS, OP, RHS, true) +#endif + +#ifndef bpf_cmp_likely +#define bpf_cmp_likely(LHS, OP, RHS) \ + ({ \ + bool ret; \ + if (__builtin_strcmp(#OP, "==") == 0) \ + ret = _bpf_cmp(LHS, !=, RHS, false); \ + else if (__builtin_strcmp(#OP, "!=") == 0) \ + ret = _bpf_cmp(LHS, ==, RHS, false); \ + else if (__builtin_strcmp(#OP, "<=") == 0) \ + ret = _bpf_cmp(LHS, >, RHS, false); \ + else if (__builtin_strcmp(#OP, "<") == 0) \ + ret = _bpf_cmp(LHS, >=, RHS, false); \ + else if (__builtin_strcmp(#OP, ">") == 0) \ + ret = _bpf_cmp(LHS, <=, RHS, false); \ + else if (__builtin_strcmp(#OP, ">=") == 0) \ + ret = _bpf_cmp(LHS, <, RHS, false); \ + else \ + (void) "bug"; \ + ret; \ + }) +#endif + /* Description * Assert that a conditional expression is true. * Returns diff --git a/tools/testing/selftests/bpf/progs/exceptions.c b/tools/testing/selftests/bpf/progs/exceptions.c index 2811ee842b01..f09cd14d8e04 100644 --- a/tools/testing/selftests/bpf/progs/exceptions.c +++ b/tools/testing/selftests/bpf/progs/exceptions.c @@ -210,7 +210,7 @@ __noinline int assert_zero_gfunc(u64 c) { volatile u64 cookie = c; - bpf_assert_eq(cookie, 0); + bpf_assert(bpf_cmp_unlikely(cookie, ==, 0)); return 0; } @@ -218,7 +218,7 @@ __noinline int assert_neg_gfunc(s64 c) { volatile s64 cookie = c; - bpf_assert_lt(cookie, 0); + bpf_assert(bpf_cmp_unlikely(cookie, <, 0)); return 0; } @@ -226,7 +226,7 @@ __noinline int assert_pos_gfunc(s64 c) { volatile s64 cookie = c; - bpf_assert_gt(cookie, 0); + bpf_assert(bpf_cmp_unlikely(cookie, >, 0)); return 0; } @@ -234,7 +234,7 @@ __noinline int assert_negeq_gfunc(s64 c) { volatile s64 cookie = c; - bpf_assert_le(cookie, -1); + bpf_assert(bpf_cmp_unlikely(cookie, <=, -1)); return 0; } @@ -242,7 +242,7 @@ __noinline int assert_poseq_gfunc(s64 c) { volatile s64 cookie = c; - bpf_assert_ge(cookie, 1); + bpf_assert(bpf_cmp_unlikely(cookie, >=, 1)); return 0; } @@ -258,7 +258,7 @@ __noinline int assert_zero_gfunc_with(u64 c) { volatile u64 cookie = c; - bpf_assert_eq_with(cookie, 0, cookie + 100); + bpf_assert_with(bpf_cmp_unlikely(cookie, ==, 0), cookie + 100); return 0; } @@ -266,7 +266,7 @@ __noinline int assert_neg_gfunc_with(s64 c) { volatile s64 cookie = c; - bpf_assert_lt_with(cookie, 0, cookie + 100); + bpf_assert_with(bpf_cmp_unlikely(cookie, <, 0), cookie + 100); return 0; } @@ -274,7 +274,7 @@ __noinline int assert_pos_gfunc_with(s64 c) { volatile s64 cookie = c; - bpf_assert_gt_with(cookie, 0, cookie + 100); + bpf_assert_with(bpf_cmp_unlikely(cookie, >, 0), cookie + 100); return 0; } @@ -282,7 +282,7 @@ __noinline int assert_negeq_gfunc_with(s64 c) { volatile s64 cookie = c; - bpf_assert_le_with(cookie, -1, cookie + 100); + bpf_assert_with(bpf_cmp_unlikely(cookie, <=, -1), cookie + 100); return 0; } @@ -290,7 +290,7 @@ __noinline int assert_poseq_gfunc_with(s64 c) { volatile s64 cookie = c; - bpf_assert_ge_with(cookie, 1, cookie + 100); + bpf_assert_with(bpf_cmp_unlikely(cookie, >=, 1), cookie + 100); return 0; } diff --git a/tools/testing/selftests/bpf/progs/iters_task_vma.c b/tools/testing/selftests/bpf/progs/iters_task_vma.c index e085a51d153e..dc0c3691dcc2 100644 --- a/tools/testing/selftests/bpf/progs/iters_task_vma.c +++ b/tools/testing/selftests/bpf/progs/iters_task_vma.c @@ -28,9 +28,8 @@ int iter_task_vma_for_each(const void *ctx) return 0; bpf_for_each(task_vma, vma, task, 0) { - if (seen >= 1000) + if (bpf_cmp_unlikely(seen, >=, 1000)) break; - barrier_var(seen); vm_ranges[seen].vm_start = vma->vm_start; vm_ranges[seen].vm_end = vma->vm_end; |