kcov.h

  1/* SPDX-License-Identifier: GPL-2.0 */
  2#ifndef _LINUX_KCOV_H
  3#define _LINUX_KCOV_H
  4
  5#include <linux/sched.h>
  6#include <uapi/linux/kcov.h>
  7
  8struct task_struct;
  9
 10#ifdef CONFIG_KCOV
 11
 12enum kcov_mode {
 13	/* Coverage collection is not enabled yet. */
 14	KCOV_MODE_DISABLED = 0,
 15	/* KCOV was initialized, but tracing mode hasn't been chosen yet. */
 16	KCOV_MODE_INIT = 1,
 17	/*
 18	 * Tracing coverage collection mode.
 19	 * Covered PCs are collected in a per-task buffer.
 20	 */
 21	KCOV_MODE_TRACE_PC = 2,
 22	/* Collecting comparison operands mode. */
 23	KCOV_MODE_TRACE_CMP = 3,
 24	/* The process owns a KCOV remote reference. */
 25	KCOV_MODE_REMOTE = 4,
 26};
 27
 28#define KCOV_IN_CTXSW	(1 << 30)
 29
 30void kcov_task_init(struct task_struct *t);
 31void kcov_task_exit(struct task_struct *t);
 32
 33#define kcov_prepare_switch(t)			\
 34do {						\
 35	(t)->kcov_mode |= KCOV_IN_CTXSW;	\
 36} while (0)
 37
 38#define kcov_finish_switch(t)			\
 39do {						\
 40	(t)->kcov_mode &= ~KCOV_IN_CTXSW;	\
 41} while (0)
 42
 43/* See Documentation/dev-tools/kcov.rst for usage details. */
 44void kcov_remote_start(u64 handle);
 45void kcov_remote_stop(void);
 46u64 kcov_common_handle(void);
 47
 48static inline void kcov_remote_start_common(u64 id)
 49{
 50	kcov_remote_start(kcov_remote_handle(KCOV_SUBSYSTEM_COMMON, id));
 51}
 52
 53static inline void kcov_remote_start_usb(u64 id)
 54{
 55	kcov_remote_start(kcov_remote_handle(KCOV_SUBSYSTEM_USB, id));
 56}
 57
 58/*
 59 * The softirq flavor of kcov_remote_*() functions is introduced as a temporary
 60 * work around for kcov's lack of nested remote coverage sections support in
 61 * task context. Adding support for nested sections is tracked in:
 62 * https://bugzilla.kernel.org/show_bug.cgi?id=210337
 63 */
 64
 65static inline void kcov_remote_start_usb_softirq(u64 id)
 66{
 67	if (in_serving_softirq() && !in_hardirq())
 68		kcov_remote_start_usb(id);
 69}
 70
 71static inline void kcov_remote_stop_softirq(void)
 72{
 73	if (in_serving_softirq() && !in_hardirq())
 74		kcov_remote_stop();
 75}
 76
 77#ifdef CONFIG_64BIT
 78typedef unsigned long kcov_u64;
 79#else
 80typedef unsigned long long kcov_u64;
 81#endif
 82
 83void __sanitizer_cov_trace_pc(void);
 84void __sanitizer_cov_trace_cmp1(u8 arg1, u8 arg2);
 85void __sanitizer_cov_trace_cmp2(u16 arg1, u16 arg2);
 86void __sanitizer_cov_trace_cmp4(u32 arg1, u32 arg2);
 87void __sanitizer_cov_trace_cmp8(kcov_u64 arg1, kcov_u64 arg2);
 88void __sanitizer_cov_trace_const_cmp1(u8 arg1, u8 arg2);
 89void __sanitizer_cov_trace_const_cmp2(u16 arg1, u16 arg2);
 90void __sanitizer_cov_trace_const_cmp4(u32 arg1, u32 arg2);
 91void __sanitizer_cov_trace_const_cmp8(kcov_u64 arg1, kcov_u64 arg2);
 92void __sanitizer_cov_trace_switch(kcov_u64 val, void *cases);
 93
 94#else
 95
 96static inline void kcov_task_init(struct task_struct *t) {}
 97static inline void kcov_task_exit(struct task_struct *t) {}
 98static inline void kcov_prepare_switch(struct task_struct *t) {}
 99static inline void kcov_finish_switch(struct task_struct *t) {}
100static inline void kcov_remote_start(u64 handle) {}
101static inline void kcov_remote_stop(void) {}
102static inline u64 kcov_common_handle(void)
103{
104	return 0;
105}
106static inline void kcov_remote_start_common(u64 id) {}
107static inline void kcov_remote_start_usb(u64 id) {}
108static inline void kcov_remote_start_usb_softirq(u64 id) {}
109static inline void kcov_remote_stop_softirq(void) {}
110
111#endif /* CONFIG_KCOV */
112#endif /* _LINUX_KCOV_H */