LXR linux/include/linux/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};
  25
  26#define KCOV_IN_CTXSW   (1 << 30)
  27
  28void kcov_task_init(struct task_struct *t);
  29void kcov_task_exit(struct task_struct *t);
  30
  31#define kcov_prepare_switch(t)                  \
  32do {                                            \
  33        (t)->kcov_mode |= KCOV_IN_CTXSW;        \
  34} while (0)
  35
  36#define kcov_finish_switch(t)                   \
  37do {                                            \
  38        (t)->kcov_mode &= ~KCOV_IN_CTXSW;       \
  39} while (0)
  40
  41/* See Documentation/dev-tools/kcov.rst for usage details. */
  42void kcov_remote_start(u64 handle);
  43void kcov_remote_stop(void);
  44u64 kcov_common_handle(void);
  45
  46static inline void kcov_remote_start_common(u64 id)
  47{
  48        kcov_remote_start(kcov_remote_handle(KCOV_SUBSYSTEM_COMMON, id));
  49}
  50
  51static inline void kcov_remote_start_usb(u64 id)
  52{
  53        kcov_remote_start(kcov_remote_handle(KCOV_SUBSYSTEM_USB, id));
  54}
  55
  56/*
  57 * The softirq flavor of kcov_remote_*() functions is introduced as a temporary
  58 * work around for kcov's lack of nested remote coverage sections support in
  59 * task context. Adding suport for nested sections is tracked in:
  60 * https://bugzilla.kernel.org/show_bug.cgi?id=210337
  61 */
  62
  63static inline void kcov_remote_start_usb_softirq(u64 id)
  64{
  65        if (in_serving_softirq())
  66                kcov_remote_start_usb(id);
  67}
  68
  69static inline void kcov_remote_stop_softirq(void)
  70{
  71        if (in_serving_softirq())
  72                kcov_remote_stop();
  73}
  74
  75#else
  76
  77static inline void kcov_task_init(struct task_struct *t) {}
  78static inline void kcov_task_exit(struct task_struct *t) {}
  79static inline void kcov_prepare_switch(struct task_struct *t) {}
  80static inline void kcov_finish_switch(struct task_struct *t) {}
  81static inline void kcov_remote_start(u64 handle) {}
  82static inline void kcov_remote_stop(void) {}
  83static inline u64 kcov_common_handle(void)
  84{
  85        return 0;
  86}
  87static inline void kcov_remote_start_common(u64 id) {}
  88static inline void kcov_remote_start_usb(u64 id) {}
  89static inline void kcov_remote_start_usb_softirq(u64 id) {}
  90static inline void kcov_remote_stop_softirq(void) {}
  91
  92#endif /* CONFIG_KCOV */
  93#endif /* _LINUX_KCOV_H */
  94