Line data    Source code

       1             : /* SPDX-License-Identifier: GPL-2.0 */
       2             : #ifndef _LINUX_KCOV_H
       3             : #define _LINUX_KCOV_H
       4             : 
       5             : #include <uapi/linux/kcov.h>
       6             : 
       7             : struct task_struct;
       8             : 
       9             : #ifdef CONFIG_KCOV
      10             : 
      11             : enum kcov_mode {
      12             :         /* Coverage collection is not enabled yet. */
      13             :         KCOV_MODE_DISABLED = 0,
      14             :         /* KCOV was initialized, but tracing mode hasn't been chosen yet. */
      15             :         KCOV_MODE_INIT = 1,
      16             :         /*
      17             :          * Tracing coverage collection mode.
      18             :          * Covered PCs are collected in a per-task buffer.
      19             :          */
      20             :         KCOV_MODE_TRACE_PC = 2,
      21             :         /* Collecting comparison operands mode. */
      22             :         KCOV_MODE_TRACE_CMP = 3,
      23             : };
      24             : 
      25             : #define KCOV_IN_CTXSW   (1 << 30)
      26             : 
      27             : void kcov_task_init(struct task_struct *t);
      28             : void kcov_task_exit(struct task_struct *t);
      29             : 
      30             : #define kcov_prepare_switch(t)                  \
      31             : do {                                            \
      32             :         (t)->kcov_mode |= KCOV_IN_CTXSW;     \
      33             : } while (0)
      34             : 
      35             : #define kcov_finish_switch(t)                   \
      36             : do {                                            \
      37             :         (t)->kcov_mode &= ~KCOV_IN_CTXSW;        \
      38             : } while (0)
      39             : 
      40             : /* See Documentation/dev-tools/kcov.rst for usage details. */
      41             : void kcov_remote_start(u64 handle);
      42             : void kcov_remote_stop(void);
      43             : u64 kcov_common_handle(void);
      44             : 
      45             : static inline void kcov_remote_start_common(u64 id)
      46             : {
      47             :         kcov_remote_start(kcov_remote_handle(KCOV_SUBSYSTEM_COMMON, id));
      48             : }
      49             : 
      50             : static inline void kcov_remote_start_usb(u64 id)
      51             : {
      52             :         kcov_remote_start(kcov_remote_handle(KCOV_SUBSYSTEM_USB, id));
      53             : }
      54             : 
      55             : /*
      56             :  * The softirq flavor of kcov_remote_*() functions is introduced as a temporary
      57             :  * work around for kcov's lack of nested remote coverage sections support in
      58             :  * task context. Adding suport for nested sections is tracked in:
      59             :  * https://bugzilla.kernel.org/show_bug.cgi?id=210337
      60             :  */
      61             : 
      62             : static inline void kcov_remote_start_usb_softirq(u64 id)
      63             : {
      64             :         if (in_serving_softirq())
      65             :                 kcov_remote_start_usb(id);
      66             : }
      67             : 
      68             : static inline void kcov_remote_stop_softirq(void)
      69             : {
      70             :         if (in_serving_softirq())
      71             :                 kcov_remote_stop();
      72             : }
      73             : 
      74             : #else
      75             : 
      76         916 : static inline void kcov_task_init(struct task_struct *t) {}
      77           0 : static inline void kcov_task_exit(struct task_struct *t) {}
      78       26511 : static inline void kcov_prepare_switch(struct task_struct *t) {}
      79       26515 : static inline void kcov_finish_switch(struct task_struct *t) {}
      80             : static inline void kcov_remote_start(u64 handle) {}
      81             : static inline void kcov_remote_stop(void) {}
      82        4864 : static inline u64 kcov_common_handle(void)
      83             : {
      84        4864 :         return 0;
      85             : }
      86             : static inline void kcov_remote_start_common(u64 id) {}
      87             : static inline void kcov_remote_start_usb(u64 id) {}
      88             : static inline void kcov_remote_start_usb_softirq(u64 id) {}
      89             : static inline void kcov_remote_stop_softirq(void) {}
      90             : 
      91             : #endif /* CONFIG_KCOV */
      92             : #endif /* _LINUX_KCOV_H */