/* SPDX-License-Identifier: GPL-2.0 */ /* * The Kernel Concurrency Sanitizer (KCSAN) infrastructure. Public interface and * data structures to set up runtime. See kcsan-checks.h for explicit checks and * modifiers. For more info please see Documentation/dev-tools/kcsan.rst. * * Copyright (C) 2019, Google LLC. */ #ifndef _LINUX_KCSAN_H #define _LINUX_KCSAN_H #include <linux/kcsan-checks.h> #include <linux/types.h> #ifdef CONFIG_KCSAN /* * Context for each thread of execution: for tasks, this is stored in * task_struct, and interrupts access internal per-CPU storage. */ struct kcsan_ctx { int disable_count; /* disable counter */ int disable_scoped; /* disable scoped access counter */ int atomic_next; /* number of following atomic ops */ /* * We distinguish between: (a) nestable atomic regions that may contain * other nestable regions; and (b) flat atomic regions that do not keep * track of nesting. Both (a) and (b) are entirely independent of each * other, and a flat region may be started in a nestable region or * vice-versa. * * This is required because, for example, in the annotations for * seqlocks, we declare seqlock writer critical sections as (a) nestable * atomic regions, but reader critical sections as (b) flat atomic * regions, but have encountered cases where seqlock reader critical * sections are contained within writer critical sections (the opposite * may be possible, too). * * To support these cases, we independently track the depth of nesting * for (a), and whether the leaf level is flat for (b). */ int atomic_nest_count; bool in_flat_atomic; /* * Access mask for all accesses if non-zero. */ unsigned long access_mask; /* List of scoped accesses; likely to be empty. */ struct list_head scoped_accesses; #ifdef CONFIG_KCSAN_WEAK_MEMORY /* * Scoped access for modeling access reordering to detect missing memory * barriers; only keep 1 to keep fast-path complexity manageable. */ struct kcsan_scoped_access reorder_access; #endif }; /** * kcsan_init - initialize KCSAN runtime */ void kcsan_init(void); #else /* CONFIG_KCSAN */ static inline void kcsan_init(void) { } #endif /* CONFIG_KCSAN */ #endif /* _LINUX_KCSAN_H */