Merge branch 'bpf-volatile-compare'

Alexei Starovoitov says:

====================
bpf: volatile compare

From: Alexei Starovoitov <ast@kernel.org>

v2->v3:
Debugged profiler.c regression. It was caused by basic block layout.
Introduce bpf_cmp_likely() and bpf_cmp_unlikely() macros.
Debugged redundant <<=32, >>=32 with u32 variables. Added cast workaround.

v1->v2:
Fixed issues pointed out by Daniel, added more tests, attempted to convert profiler.c,
but barrier_var() wins vs bpf_cmp(). To be investigated.
Patches 1-4 are good to go, but 5 needs more work.
====================

Link: https://lore.kernel.org/r/20231226191148.48536-1-alexei.starovoitov@gmail.comSigned-off-by: Andrii Nakryiko <andrii@kernel.org>

tools/testing/selftests/bpf/Makefile

@@ -383,6 +383,7 @@ CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG),$(CLANG_TARGET_ARCH))
 BPF_CFLAGS = -g -Wall -Werror -D__TARGET_ARCH_$(SRCARCH) $(MENDIAN)	\
 	     -I$(INCLUDE_DIR) -I$(CURDIR) -I$(APIDIR)			\
 	     -I$(abspath $(OUTPUT)/../usr/include)
+# TODO: enable me -Wsign-compare
 
 CLANG_CFLAGS = $(CLANG_SYS_INCLUDES) \
 	       -Wno-compare-distinct-pointer-types

tools/testing/selftests/bpf/bpf_experimental.h

@@ -254,173 +254,97 @@ extern void bpf_throw(u64 cookie) __ksym;
 		}									\
 	 })
 
-/* Description
- *	Assert that a conditional expression is true.
- * Returns
- *	Void.
- * Throws
- *	An exception with the value zero when the assertion fails.
- */
-#define bpf_assert(cond) if (!(cond)) bpf_throw(0);
-
-/* Description
- *	Assert that a conditional expression is true.
- * Returns
- *	Void.
- * Throws
- *	An exception with the specified value when the assertion fails.
- */
-#define bpf_assert_with(cond, value) if (!(cond)) bpf_throw(value);
-
-/* Description
- *	Assert that LHS is equal to RHS. This statement updates the known value
- *	of LHS during verification. Note that RHS must be a constant value, and
- *	must fit within the data type of LHS.
- * Returns
- *	Void.
- * Throws
- *	An exception with the value zero when the assertion fails.
- */
-#define bpf_assert_eq(LHS, RHS)						\
-	({								\
-		barrier_var(LHS);					\
-		__bpf_assert_op(LHS, ==, RHS, 0, true);			\
-	})
-
-/* Description
- *	Assert that LHS is equal to RHS. This statement updates the known value
- *	of LHS during verification. Note that RHS must be a constant value, and
- *	must fit within the data type of LHS.
- * Returns
- *	Void.
- * Throws
- *	An exception with the specified value when the assertion fails.
- */
-#define bpf_assert_eq_with(LHS, RHS, value)				\
-	({								\
-		barrier_var(LHS);					\
-		__bpf_assert_op(LHS, ==, RHS, value, true);		\
-	})
-
-/* Description
- *	Assert that LHS is less than RHS. This statement updates the known
- *	bounds of LHS during verification. Note that RHS must be a constant
- *	value, and must fit within the data type of LHS.
- * Returns
- *	Void.
- * Throws
- *	An exception with the value zero when the assertion fails.
- */
-#define bpf_assert_lt(LHS, RHS)						\
-	({								\
-		barrier_var(LHS);					\
-		__bpf_assert_op(LHS, <, RHS, 0, false);			\
-	})
-
-/* Description
- *	Assert that LHS is less than RHS. This statement updates the known
- *	bounds of LHS during verification. Note that RHS must be a constant
- *	value, and must fit within the data type of LHS.
- * Returns
- *	Void.
- * Throws
- *	An exception with the specified value when the assertion fails.
- */
-#define bpf_assert_lt_with(LHS, RHS, value)				\
-	({								\
-		barrier_var(LHS);					\
-		__bpf_assert_op(LHS, <, RHS, value, false);		\
-	})
+#define __cmp_cannot_be_signed(x) \
+	__builtin_strcmp(#x, "==") == 0 || __builtin_strcmp(#x, "!=") == 0 || \
+	__builtin_strcmp(#x, "&") == 0
 
-/* Description
- *	Assert that LHS is greater than RHS. This statement updates the known
- *	bounds of LHS during verification. Note that RHS must be a constant
- *	value, and must fit within the data type of LHS.
- * Returns
- *	Void.
- * Throws
- *	An exception with the value zero when the assertion fails.
- */
-#define bpf_assert_gt(LHS, RHS)						\
-	({								\
-		barrier_var(LHS);					\
-		__bpf_assert_op(LHS, >, RHS, 0, false);			\
-	})
+#define __is_signed_type(type) (((type)(-1)) < (type)1)
 
-/* Description
- *	Assert that LHS is greater than RHS. This statement updates the known
- *	bounds of LHS during verification. Note that RHS must be a constant
- *	value, and must fit within the data type of LHS.
- * Returns
- *	Void.
- * Throws
- *	An exception with the specified value when the assertion fails.
+#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_assert_gt_with(LHS, RHS, value)				\
-	({								\
-		barrier_var(LHS);					\
-		__bpf_assert_op(LHS, >, RHS, value, false);		\
-	})
+#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
 
-/* Description
- *	Assert that LHS is less than or equal to RHS. This statement updates the
- *	known bounds of LHS during verification. Note that RHS must be a
- *	constant value, and must fit within the data type of LHS.
- * Returns
- *	Void.
- * Throws
- *	An exception with the value zero when the assertion fails.
- */
-#define bpf_assert_le(LHS, RHS)						\
-	({								\
-		barrier_var(LHS);					\
-		__bpf_assert_op(LHS, <=, RHS, 0, false);		\
-	})
+#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 LHS is less than or equal to RHS. This statement updates the
- *	known bounds of LHS during verification. Note that RHS must be a
- *	constant value, and must fit within the data type of LHS.
- * Returns
- *	Void.
- * Throws
- *	An exception with the specified value when the assertion fails.
- */
-#define bpf_assert_le_with(LHS, RHS, value)				\
-	({								\
-		barrier_var(LHS);					\
-		__bpf_assert_op(LHS, <=, RHS, value, false);		\
-	})
+#ifndef bpf_nop_mov
+#define bpf_nop_mov(var) \
+	asm volatile("%[reg]=%[reg]"::[reg]"r"((short)var))
+#endif
 
 /* Description
- *	Assert that LHS is greater than or equal to RHS. This statement updates
- *	the known bounds of LHS during verification. Note that RHS must be a
- *	constant value, and must fit within the data type of LHS.
+ *	Assert that a conditional expression is true.
  * Returns
  *	Void.
  * Throws
  *	An exception with the value zero when the assertion fails.
  */
-#define bpf_assert_ge(LHS, RHS)						\
-	({								\
-		barrier_var(LHS);					\
-		__bpf_assert_op(LHS, >=, RHS, 0, false);		\
-	})
+#define bpf_assert(cond) if (!(cond)) bpf_throw(0);
 
 /* Description
- *	Assert that LHS is greater than or equal to RHS. This statement updates
- *	the known bounds of LHS during verification. Note that RHS must be a
- *	constant value, and must fit within the data type of LHS.
+ *	Assert that a conditional expression is true.
  * Returns
  *	Void.
  * Throws
  *	An exception with the specified value when the assertion fails.
  */
-#define bpf_assert_ge_with(LHS, RHS, value)				\
-	({								\
-		barrier_var(LHS);					\
-		__bpf_assert_op(LHS, >=, RHS, value, false);		\
-	})
+#define bpf_assert_with(cond, value) if (!(cond)) bpf_throw(value);
 
 /* Description
  *	Assert that LHS is in the range [BEG, END] (inclusive of both). This

tools/testing/selftests/bpf/progs/bpf_iter_bpf_percpu_hash_map.c

@@ -20,7 +20,7 @@ struct {
 } hashmap1 SEC(".maps");
 
 /* will set before prog run */
-volatile const __u32 num_cpus = 0;
+volatile const __s32 num_cpus = 0;
 
 /* will collect results during prog run */
 __u32 key_sum_a = 0, key_sum_b = 0, key_sum_c = 0;

tools/testing/selftests/bpf/progs/bpf_iter_task_vmas.c

@@ -35,7 +35,7 @@ SEC("iter/task_vma") int proc_maps(struct bpf_iter__task_vma *ctx)
 		return 0;
 
 	file = vma->vm_file;
-	if (task->tgid != pid) {
+	if (task->tgid != (pid_t)pid) {
 		if (one_task)
 			one_task_error = 1;
 		return 0;

tools/testing/selftests/bpf/progs/bpf_iter_tasks.c

@@ -22,7 +22,7 @@ int dump_task(struct bpf_iter__task *ctx)
 		return 0;
 	}
 
-	if (task->pid != tid)
+	if (task->pid != (pid_t)tid)
 		num_unknown_tid++;
 	else
 		num_known_tid++;

tools/testing/selftests/bpf/progs/bpf_iter_test_kern4.c

@@ -45,7 +45,7 @@ int dump_bpf_map(struct bpf_iter__bpf_map *ctx)
 	}
 
 	/* fill seq_file buffer */
-	for (i = 0; i < print_len; i++)
+	for (i = 0; i < (int)print_len; i++)
 		bpf_seq_write(seq, &seq_num, sizeof(seq_num));
 
 	return ret;

tools/testing/selftests/bpf/progs/cgroup_getset_retval_setsockopt.c

@@ -11,7 +11,7 @@
 __u32 invocations = 0;
 __u32 assertion_error = 0;
 __u32 retval_value = 0;
-__u32 page_size = 0;
+__s32 page_size = 0;
 
 SEC("cgroup/setsockopt")
 int get_retval(struct bpf_sockopt *ctx)

tools/testing/selftests/bpf/progs/cgrp_ls_sleepable.c

@@ -15,7 +15,7 @@ struct {
 	__type(value, long);
 } map_a SEC(".maps");
 
-__u32 target_pid;
+__s32 target_pid;
 __u64 cgroup_id;
 int target_hid;
 bool is_cgroup1;

tools/testing/selftests/bpf/progs/cpumask_success.c

@@ -332,7 +332,7 @@ SEC("tp_btf/task_newtask")
 int BPF_PROG(test_copy_any_anyand, struct task_struct *task, u64 clone_flags)
 {
 	struct bpf_cpumask *mask1, *mask2, *dst1, *dst2;
-	u32 cpu;
+	int cpu;
 
 	if (!is_test_task())
 		return 0;

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;
 }
 

tools/testing/selftests/bpf/progs/exceptions_assert.c

@@ -11,51 +11,51 @@
 #define check_assert(type, op, name, value)				\
 	SEC("?tc")							\
 	__log_level(2) __failure					\
-	int check_assert_##op##_##name(void *ctx)			\
+	int check_assert_##name(void *ctx)				\
 	{								\
 		type num = bpf_ktime_get_ns();				\
-		bpf_assert_##op(num, value);				\
+		bpf_assert(bpf_cmp_unlikely(num, op, value));		\
 		return *(u64 *)num;					\
 	}
 
-__msg(": R0_w=0xffffffff80000000 R10=fp0")
-check_assert(s64, eq, int_min, INT_MIN);
-__msg(": R0_w=0x7fffffff R10=fp0")
-check_assert(s64, eq, int_max, INT_MAX);
-__msg(": R0_w=0 R10=fp0")
-check_assert(s64, eq, zero, 0);
-__msg(": R0_w=0x8000000000000000 R1_w=0x8000000000000000 R10=fp0")
-check_assert(s64, eq, llong_min, LLONG_MIN);
-__msg(": R0_w=0x7fffffffffffffff R1_w=0x7fffffffffffffff R10=fp0")
-check_assert(s64, eq, llong_max, LLONG_MAX);
-
-__msg(": R0_w=scalar(smax=0x7ffffffe) R10=fp0")
-check_assert(s64, lt, pos, INT_MAX);
-__msg(": R0_w=scalar(smax=-1,umin=0x8000000000000000,var_off=(0x8000000000000000; 0x7fffffffffffffff))")
-check_assert(s64, lt, zero, 0);
-__msg(": R0_w=scalar(smax=0xffffffff7fffffff,umin=0x8000000000000000,umax=0xffffffff7fffffff,var_off=(0x8000000000000000; 0x7fffffffffffffff))")
-check_assert(s64, lt, neg, INT_MIN);
-
-__msg(": R0_w=scalar(smax=0x7fffffff) R10=fp0")
-check_assert(s64, le, pos, INT_MAX);
-__msg(": R0_w=scalar(smax=0) R10=fp0")
-check_assert(s64, le, zero, 0);
-__msg(": R0_w=scalar(smax=0xffffffff80000000,umin=0x8000000000000000,umax=0xffffffff80000000,var_off=(0x8000000000000000; 0x7fffffffffffffff))")
-check_assert(s64, le, neg, INT_MIN);
-
-__msg(": R0_w=scalar(smin=umin=0x80000000,umax=0x7fffffffffffffff,var_off=(0x0; 0x7fffffffffffffff))")
-check_assert(s64, gt, pos, INT_MAX);
-__msg(": R0_w=scalar(smin=umin=1,umax=0x7fffffffffffffff,var_off=(0x0; 0x7fffffffffffffff))")
-check_assert(s64, gt, zero, 0);
-__msg(": R0_w=scalar(smin=0xffffffff80000001) R10=fp0")
-check_assert(s64, gt, neg, INT_MIN);
-
-__msg(": R0_w=scalar(smin=umin=0x7fffffff,umax=0x7fffffffffffffff,var_off=(0x0; 0x7fffffffffffffff))")
-check_assert(s64, ge, pos, INT_MAX);
-__msg(": R0_w=scalar(smin=0,umax=0x7fffffffffffffff,var_off=(0x0; 0x7fffffffffffffff)) R10=fp0")
-check_assert(s64, ge, zero, 0);
-__msg(": R0_w=scalar(smin=0xffffffff80000000) R10=fp0")
-check_assert(s64, ge, neg, INT_MIN);
+__msg(": R0_w=0xffffffff80000000")
+check_assert(s64, ==, eq_int_min, INT_MIN);
+__msg(": R0_w=0x7fffffff")
+check_assert(s64, ==, eq_int_max, INT_MAX);
+__msg(": R0_w=0")
+check_assert(s64, ==, eq_zero, 0);
+__msg(": R0_w=0x8000000000000000 R1_w=0x8000000000000000")
+check_assert(s64, ==, eq_llong_min, LLONG_MIN);
+__msg(": R0_w=0x7fffffffffffffff R1_w=0x7fffffffffffffff")
+check_assert(s64, ==, eq_llong_max, LLONG_MAX);
+
+__msg(": R0_w=scalar(id=1,smax=0x7ffffffe)")
+check_assert(s64, <, lt_pos, INT_MAX);
+__msg(": R0_w=scalar(id=1,smax=-1,umin=0x8000000000000000,var_off=(0x8000000000000000; 0x7fffffffffffffff))")
+check_assert(s64, <, lt_zero, 0);
+__msg(": R0_w=scalar(id=1,smax=0xffffffff7fffffff")
+check_assert(s64, <, lt_neg, INT_MIN);
+
+__msg(": R0_w=scalar(id=1,smax=0x7fffffff)")
+check_assert(s64, <=, le_pos, INT_MAX);
+__msg(": R0_w=scalar(id=1,smax=0)")
+check_assert(s64, <=, le_zero, 0);
+__msg(": R0_w=scalar(id=1,smax=0xffffffff80000000")
+check_assert(s64, <=, le_neg, INT_MIN);
+
+__msg(": R0_w=scalar(id=1,smin=umin=0x80000000,umax=0x7fffffffffffffff,var_off=(0x0; 0x7fffffffffffffff))")
+check_assert(s64, >, gt_pos, INT_MAX);
+__msg(": R0_w=scalar(id=1,smin=umin=1,umax=0x7fffffffffffffff,var_off=(0x0; 0x7fffffffffffffff))")
+check_assert(s64, >, gt_zero, 0);
+__msg(": R0_w=scalar(id=1,smin=0xffffffff80000001")
+check_assert(s64, >, gt_neg, INT_MIN);
+
+__msg(": R0_w=scalar(id=1,smin=umin=0x7fffffff,umax=0x7fffffffffffffff,var_off=(0x0; 0x7fffffffffffffff))")
+check_assert(s64, >=, ge_pos, INT_MAX);
+__msg(": R0_w=scalar(id=1,smin=0,umax=0x7fffffffffffffff,var_off=(0x0; 0x7fffffffffffffff))")
+check_assert(s64, >=, ge_zero, 0);
+__msg(": R0_w=scalar(id=1,smin=0xffffffff80000000")
+check_assert(s64, >=, ge_neg, INT_MIN);
 
 SEC("?tc")
 __log_level(2) __failure

tools/testing/selftests/bpf/progs/iters.c

@@ -6,7 +6,7 @@
 #include <bpf/bpf_helpers.h>
 #include "bpf_misc.h"
 
-#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
+#define ARRAY_SIZE(x) (int)(sizeof(x) / sizeof((x)[0]))
 
 static volatile int zero = 0;
 
@@ -676,7 +676,7 @@ static __noinline int sum(struct bpf_iter_num *it, int *arr, __u32 n)
 
 	while ((t = bpf_iter_num_next(it))) {
 		i = *t;
-		if (i >= n)
+		if ((__u32)i >= n)
 			break;
 		sum += arr[i];
 	}

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;

tools/testing/selftests/bpf/progs/linked_funcs1.c

@@ -8,7 +8,7 @@
 #include "bpf_misc.h"
 
 /* weak and shared between two files */
-const volatile int my_tid __weak;
+const volatile __u32 my_tid __weak;
 long syscall_id __weak;
 
 int output_val1;

tools/testing/selftests/bpf/progs/linked_funcs2.c

@@ -68,7 +68,7 @@ int BPF_PROG(handler2, struct pt_regs *regs, long id)
 {
 	static volatile int whatever;
 
-	if (my_tid != (u32)bpf_get_current_pid_tgid() || id != syscall_id)
+	if (my_tid != (s32)bpf_get_current_pid_tgid() || id != syscall_id)
 		return 0;
 
 	/* make sure we have CO-RE relocations in main program */

tools/testing/selftests/bpf/progs/linked_list.c

@@ -6,7 +6,7 @@
 #include "bpf_experimental.h"
 
 #ifndef ARRAY_SIZE
-#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
+#define ARRAY_SIZE(x) (int)(sizeof(x) / sizeof((x)[0]))
 #endif
 
 #include "linked_list.h"

tools/testing/selftests/bpf/progs/local_storage.c

@@ -13,7 +13,7 @@ char _license[] SEC("license") = "GPL";
 
 #define DUMMY_STORAGE_VALUE 0xdeadbeef
 
-int monitored_pid = 0;
+__u32 monitored_pid = 0;
 int inode_storage_result = -1;
 int sk_storage_result = -1;
 int task_storage_result = -1;

tools/testing/selftests/bpf/progs/lsm.c

@@ -92,7 +92,7 @@ int BPF_PROG(test_int_hook, struct vm_area_struct *vma,
 	if (ret != 0)
 		return ret;
 
-	__u32 pid = bpf_get_current_pid_tgid() >> 32;
+	__s32 pid = bpf_get_current_pid_tgid() >> 32;
 	int is_stack = 0;
 
 	is_stack = (vma->vm_start <= vma->vm_mm->start_stack &&

tools/testing/selftests/bpf/progs/normal_map_btf.c

@@ -36,7 +36,7 @@ int add_to_list_in_array(void *ctx)
 	struct node_data *new;
 	int zero = 0;
 
-	if (done || (u32)bpf_get_current_pid_tgid() != pid)
+	if (done || (int)bpf_get_current_pid_tgid() != pid)
 		return 0;
 
 	value = bpf_map_lookup_elem(&array, &zero);

tools/testing/selftests/bpf/progs/profiler.inc.h

@@ -7,6 +7,7 @@
 
 #include "profiler.h"
 #include "err.h"
+#include "bpf_experimental.h"
 
 #ifndef NULL
 #define NULL 0
@@ -132,7 +133,7 @@ struct {
 } disallowed_exec_inodes SEC(".maps");
 
 #ifndef ARRAY_SIZE
-#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0]))
+#define ARRAY_SIZE(arr) (int)(sizeof(arr) / sizeof(arr[0]))
 #endif
 
 static INLINE bool IS_ERR(const void* ptr)
@@ -221,8 +222,7 @@ static INLINE void* read_full_cgroup_path(struct kernfs_node* cgroup_node,
 			return payload;
 		if (cgroup_node == cgroup_root_node)
 			*root_pos = payload - payload_start;
-		if (filepart_length <= MAX_PATH) {
-			barrier_var(filepart_length);
+		if (bpf_cmp_likely(filepart_length, <=, MAX_PATH)) {
 			payload += filepart_length;
 		}
 		cgroup_node = BPF_CORE_READ(cgroup_node, parent);
@@ -305,9 +305,7 @@ static INLINE void* populate_cgroup_info(struct cgroup_data_t* cgroup_data,
 	size_t cgroup_root_length =
 		bpf_probe_read_kernel_str(payload, MAX_PATH,
 					  BPF_CORE_READ(root_kernfs, name));
-	barrier_var(cgroup_root_length);
-	if (cgroup_root_length <= MAX_PATH) {
-		barrier_var(cgroup_root_length);
+	if (bpf_cmp_likely(cgroup_root_length, <=, MAX_PATH)) {
 		cgroup_data->cgroup_root_length = cgroup_root_length;
 		payload += cgroup_root_length;
 	}
@@ -315,9 +313,7 @@ static INLINE void* populate_cgroup_info(struct cgroup_data_t* cgroup_data,
 	size_t cgroup_proc_length =
 		bpf_probe_read_kernel_str(payload, MAX_PATH,
 					  BPF_CORE_READ(proc_kernfs, name));
-	barrier_var(cgroup_proc_length);
-	if (cgroup_proc_length <= MAX_PATH) {
-		barrier_var(cgroup_proc_length);
+	if (bpf_cmp_likely(cgroup_proc_length, <=, MAX_PATH)) {
 		cgroup_data->cgroup_proc_length = cgroup_proc_length;
 		payload += cgroup_proc_length;
 	}
@@ -347,9 +343,7 @@ static INLINE void* populate_var_metadata(struct var_metadata_t* metadata,
 	metadata->comm_length = 0;
 
 	size_t comm_length = bpf_core_read_str(payload, TASK_COMM_LEN, &task->comm);
-	barrier_var(comm_length);
-	if (comm_length <= TASK_COMM_LEN) {
-		barrier_var(comm_length);
+	if (bpf_cmp_likely(comm_length, <=, TASK_COMM_LEN)) {
 		metadata->comm_length = comm_length;
 		payload += comm_length;
 	}
@@ -494,10 +488,9 @@ read_absolute_file_path_from_dentry(struct dentry* filp_dentry, void* payload)
 		filepart_length =
 			bpf_probe_read_kernel_str(payload, MAX_PATH,
 						  BPF_CORE_READ(filp_dentry, d_name.name));
-		barrier_var(filepart_length);
-		if (filepart_length > MAX_PATH)
+		bpf_nop_mov(filepart_length);
+		if (bpf_cmp_unlikely(filepart_length, >, MAX_PATH))
 			break;
-		barrier_var(filepart_length);
 		payload += filepart_length;
 		length += filepart_length;
 
@@ -579,9 +572,7 @@ ssize_t BPF_KPROBE(kprobe__proc_sys_write,
 
 	size_t sysctl_val_length = bpf_probe_read_kernel_str(payload,
 							     CTL_MAXNAME, buf);
-	barrier_var(sysctl_val_length);
-	if (sysctl_val_length <= CTL_MAXNAME) {
-		barrier_var(sysctl_val_length);
+	if (bpf_cmp_likely(sysctl_val_length, <=, CTL_MAXNAME)) {
 		sysctl_data->sysctl_val_length = sysctl_val_length;
 		payload += sysctl_val_length;
 	}
@@ -590,9 +581,7 @@ ssize_t BPF_KPROBE(kprobe__proc_sys_write,
 		bpf_probe_read_kernel_str(payload, MAX_PATH,
 					  BPF_CORE_READ(filp, f_path.dentry,
 							d_name.name));
-	barrier_var(sysctl_path_length);
-	if (sysctl_path_length <= MAX_PATH) {
-		barrier_var(sysctl_path_length);
+	if (bpf_cmp_likely(sysctl_path_length, <=, MAX_PATH)) {
 		sysctl_data->sysctl_path_length = sysctl_path_length;
 		payload += sysctl_path_length;
 	}
@@ -645,7 +634,7 @@ int raw_tracepoint__sched_process_exit(void* ctx)
 	for (int i = 0; i < ARRAY_SIZE(arr_struct->array); i++) {
 		struct var_kill_data_t* past_kill_data = &arr_struct->array[i];
 
-		if (past_kill_data != NULL && past_kill_data->kill_target_pid == tpid) {
+		if (past_kill_data != NULL && past_kill_data->kill_target_pid == (pid_t)tpid) {
 			bpf_probe_read_kernel(kill_data, sizeof(*past_kill_data),
 					      past_kill_data);
 			void* payload = kill_data->payload;
@@ -658,9 +647,7 @@ int raw_tracepoint__sched_process_exit(void* ctx)
 			kill_data->kill_target_cgroup_proc_length = 0;
 
 			size_t comm_length = bpf_core_read_str(payload, TASK_COMM_LEN, &task->comm);
-			barrier_var(comm_length);
-			if (comm_length <= TASK_COMM_LEN) {
-				barrier_var(comm_length);
+			if (bpf_cmp_likely(comm_length, <=, TASK_COMM_LEN)) {
 				kill_data->kill_target_name_length = comm_length;
 				payload += comm_length;
 			}
@@ -669,9 +656,7 @@ int raw_tracepoint__sched_process_exit(void* ctx)
 				bpf_probe_read_kernel_str(payload,
 							  KILL_TARGET_LEN,
 							  BPF_CORE_READ(proc_kernfs, name));
-			barrier_var(cgroup_proc_length);
-			if (cgroup_proc_length <= KILL_TARGET_LEN) {
-				barrier_var(cgroup_proc_length);
+			if (bpf_cmp_likely(cgroup_proc_length, <=, KILL_TARGET_LEN)) {
 				kill_data->kill_target_cgroup_proc_length = cgroup_proc_length;
 				payload += cgroup_proc_length;
 			}
@@ -731,9 +716,7 @@ int raw_tracepoint__sched_process_exec(struct bpf_raw_tracepoint_args* ctx)
 	const char* filename = BPF_CORE_READ(bprm, filename);
 	size_t bin_path_length =
 		bpf_probe_read_kernel_str(payload, MAX_FILENAME_LEN, filename);
-	barrier_var(bin_path_length);
-	if (bin_path_length <= MAX_FILENAME_LEN) {
-		barrier_var(bin_path_length);
+	if (bpf_cmp_likely(bin_path_length, <=, MAX_FILENAME_LEN)) {
 		proc_exec_data->bin_path_length = bin_path_length;
 		payload += bin_path_length;
 	}
@@ -743,8 +726,7 @@ int raw_tracepoint__sched_process_exec(struct bpf_raw_tracepoint_args* ctx)
 	unsigned int cmdline_length = probe_read_lim(payload, arg_start,
 						     arg_end - arg_start, MAX_ARGS_LEN);
 
-	if (cmdline_length <= MAX_ARGS_LEN) {
-		barrier_var(cmdline_length);
+	if (bpf_cmp_likely(cmdline_length, <=, MAX_ARGS_LEN)) {
 		proc_exec_data->cmdline_length = cmdline_length;
 		payload += cmdline_length;
 	}
@@ -821,9 +803,7 @@ int kprobe_ret__do_filp_open(struct pt_regs* ctx)
 	payload = populate_cgroup_info(&filemod_data->cgroup_data, task, payload);
 
 	size_t len = read_absolute_file_path_from_dentry(filp_dentry, payload);
-	barrier_var(len);
-	if (len <= MAX_FILEPATH_LENGTH) {
-		barrier_var(len);
+	if (bpf_cmp_likely(len, <=, MAX_FILEPATH_LENGTH)) {
 		payload += len;
 		filemod_data->dst_filepath_length = len;
 	}
@@ -876,17 +856,13 @@ int BPF_KPROBE(kprobe__vfs_link,
 	payload = populate_cgroup_info(&filemod_data->cgroup_data, task, payload);
 
 	size_t len = read_absolute_file_path_from_dentry(old_dentry, payload);
-	barrier_var(len);
-	if (len <= MAX_FILEPATH_LENGTH) {
-		barrier_var(len);
+	if (bpf_cmp_likely(len, <=, MAX_FILEPATH_LENGTH)) {
 		payload += len;
 		filemod_data->src_filepath_length = len;
 	}
 
 	len = read_absolute_file_path_from_dentry(new_dentry, payload);
-	barrier_var(len);
-	if (len <= MAX_FILEPATH_LENGTH) {
-		barrier_var(len);
+	if (bpf_cmp_likely(len, <=, MAX_FILEPATH_LENGTH)) {
 		payload += len;
 		filemod_data->dst_filepath_length = len;
 	}
@@ -936,16 +912,12 @@ int BPF_KPROBE(kprobe__vfs_symlink, struct inode* dir, struct dentry* dentry,
 
 	size_t len = bpf_probe_read_kernel_str(payload, MAX_FILEPATH_LENGTH,
 					       oldname);
-	barrier_var(len);
-	if (len <= MAX_FILEPATH_LENGTH) {
-		barrier_var(len);
+	if (bpf_cmp_likely(len, <=, MAX_FILEPATH_LENGTH)) {
 		payload += len;
 		filemod_data->src_filepath_length = len;
 	}
 	len = read_absolute_file_path_from_dentry(dentry, payload);
-	barrier_var(len);
-	if (len <= MAX_FILEPATH_LENGTH) {
-		barrier_var(len);
+	if (bpf_cmp_likely(len, <=, MAX_FILEPATH_LENGTH)) {
 		payload += len;
 		filemod_data->dst_filepath_length = len;
 	}

tools/testing/selftests/bpf/progs/sockopt_inherit.c

@@ -9,7 +9,7 @@ char _license[] SEC("license") = "GPL";
 #define CUSTOM_INHERIT2			1
 #define CUSTOM_LISTENER			2
 
-__u32 page_size = 0;
+__s32 page_size = 0;
 
 struct sockopt_inherit {
 	__u8 val;

tools/testing/selftests/bpf/progs/sockopt_multi.c

@@ -5,7 +5,7 @@
 
 char _license[] SEC("license") = "GPL";
 
-__u32 page_size = 0;
+__s32 page_size = 0;
 
 SEC("cgroup/getsockopt")
 int _getsockopt_child(struct bpf_sockopt *ctx)

tools/testing/selftests/bpf/progs/sockopt_qos_to_cc.c

@@ -9,7 +9,7 @@
 
 char _license[] SEC("license") = "GPL";
 
-__u32 page_size = 0;
+__s32 page_size = 0;
 
 SEC("cgroup/setsockopt")
 int sockopt_qos_to_cc(struct bpf_sockopt *ctx)

tools/testing/selftests/bpf/progs/test_bpf_ma.c

@@ -21,7 +21,7 @@ const unsigned int data_sizes[] = {16, 32, 64, 96, 128, 192, 256, 512, 1024, 204
 const volatile unsigned int data_btf_ids[ARRAY_SIZE(data_sizes)] = {};
 
 int err = 0;
-int pid = 0;
+u32 pid = 0;
 
 #define DEFINE_ARRAY_WITH_KPTR(_size) \
 	struct bin_data_##_size { \

tools/testing/selftests/bpf/progs/test_core_reloc_kernel.c

@@ -53,7 +53,7 @@ int test_core_kernel(void *ctx)
 	struct task_struct *task = (void *)bpf_get_current_task();
 	struct core_reloc_kernel_output *out = (void *)&data.out;
 	uint64_t pid_tgid = bpf_get_current_pid_tgid();
-	uint32_t real_tgid = (uint32_t)pid_tgid;
+	int32_t real_tgid = (int32_t)pid_tgid;
 	int pid, tgid;
 
 	if (data.my_pid_tgid != pid_tgid)

tools/testing/selftests/bpf/progs/test_core_reloc_module.c

@@ -43,8 +43,8 @@ int BPF_PROG(test_core_module_probed,
 #if __has_builtin(__builtin_preserve_enum_value)
 	struct core_reloc_module_output *out = (void *)&data.out;
 	__u64 pid_tgid = bpf_get_current_pid_tgid();
-	__u32 real_tgid = (__u32)(pid_tgid >> 32);
-	__u32 real_pid = (__u32)pid_tgid;
+	__s32 real_tgid = (__s32)(pid_tgid >> 32);
+	__s32 real_pid = (__s32)pid_tgid;
 
 	if (data.my_pid_tgid != pid_tgid)
 		return 0;
@@ -77,8 +77,8 @@ int BPF_PROG(test_core_module_direct,
 #if __has_builtin(__builtin_preserve_enum_value)
 	struct core_reloc_module_output *out = (void *)&data.out;
 	__u64 pid_tgid = bpf_get_current_pid_tgid();
-	__u32 real_tgid = (__u32)(pid_tgid >> 32);
-	__u32 real_pid = (__u32)pid_tgid;
+	__s32 real_tgid = (__s32)(pid_tgid >> 32);
+	__s32 real_pid = (__s32)pid_tgid;
 
 	if (data.my_pid_tgid != pid_tgid)
 		return 0;

tools/testing/selftests/bpf/progs/test_fsverity.c

@@ -38,7 +38,7 @@ int BPF_PROG(test_file_open, struct file *f)
 		return 0;
 	got_fsverity = 1;
 
-	for (i = 0; i < sizeof(digest); i++) {
+	for (i = 0; i < (int)sizeof(digest); i++) {
 		if (digest[i] != expected_digest[i])
 			return 0;
 	}

tools/testing/selftests/bpf/progs/test_skc_to_unix_sock.c

@@ -29,7 +29,7 @@ int BPF_PROG(unix_listen, struct socket *sock, int backlog)
 	len = unix_sk->addr->len - sizeof(short);
 	path[0] = '@';
 	for (i = 1; i < len; i++) {
-		if (i >= sizeof(struct sockaddr_un))
+		if (i >= (int)sizeof(struct sockaddr_un))
 			break;
 
 		path[i] = unix_sk->addr->name->sun_path[i];

tools/testing/selftests/bpf/progs/test_xdp_do_redirect.c

@@ -38,7 +38,7 @@ int xdp_redirect(struct xdp_md *xdp)
 	if (payload + 1 > data_end)
 		return XDP_ABORTED;
 
-	if (xdp->ingress_ifindex != ifindex_in)
+	if (xdp->ingress_ifindex != (__u32)ifindex_in)
 		return XDP_ABORTED;
 
 	if (metadata + 1 > data)