linux-zen-server/include/linux/kcsan.h

76 lines
2.2 KiB
C

/* 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 */