mirror of
https://github.com/jart/cosmopolitan.git
synced 2025-06-05 04:02:28 +00:00
af7bd80430
This change introduces a new deadlock detector for Cosmo's POSIX threads implementation. Error check mutexes will now track a DAG of nested locks and report EDEADLK when a deadlock is theoretically possible. These will occur rarely, but it's important for production hardening your code. You don't even need to change your mutexes to use the POSIX error check mode because `cosmocc -mdbg` will enable error checking on mutexes by default globally. When cycles are found, an error message showing your demangled symbols describing the strongly connected component are printed and then the SIGTRAP is raised, which means you'll also get a backtrace if you're using ShowCrashReports() too. This new error checker is so low-level and so pure that it's able to verify the relationships of every libc runtime lock, including those locks upon which the mutex implementation depends.
89 lines
2.2 KiB
C
89 lines
2.2 KiB
C
#ifndef COSMOPOLITAN_MAPS_H_
|
|
#define COSMOPOLITAN_MAPS_H_
|
|
#include "libc/intrin/atomic.h"
|
|
#include "libc/intrin/tree.h"
|
|
#include "libc/runtime/runtime.h"
|
|
COSMOPOLITAN_C_START_
|
|
|
|
#define MAPS_RETRY ((void *)-1)
|
|
|
|
#define MAP_TREE_CONTAINER(e) TREE_CONTAINER(struct Map, tree, e)
|
|
|
|
struct Map {
|
|
char *addr; /* granule aligned */
|
|
size_t size; /* must be nonzero */
|
|
int64_t off; /* ignore for anon */
|
|
int prot; /* memory protects */
|
|
int flags; /* memory map flag */
|
|
bool iscow; /* windows nt only */
|
|
bool readonlyfile; /* windows nt only */
|
|
unsigned visited; /* checks and fork */
|
|
intptr_t hand; /* windows nt only */
|
|
union {
|
|
struct Tree tree;
|
|
struct Map *freed;
|
|
};
|
|
};
|
|
|
|
struct MapLock {
|
|
void *edges;
|
|
_Atomic(uint64_t) word;
|
|
};
|
|
|
|
struct Maps {
|
|
uint128_t rand;
|
|
struct Tree *maps;
|
|
struct MapLock lock;
|
|
_Atomic(uintptr_t) freed;
|
|
size_t count;
|
|
size_t pages;
|
|
char *pick;
|
|
struct Map stack;
|
|
struct Map guard;
|
|
};
|
|
|
|
struct AddrSize {
|
|
char *addr;
|
|
size_t size;
|
|
};
|
|
|
|
extern struct Maps __maps;
|
|
|
|
void __maps_init(void);
|
|
bool __maps_lock(void);
|
|
void __maps_check(void);
|
|
void __maps_unlock(void);
|
|
void *__maps_randaddr(void);
|
|
void __maps_add(struct Map *);
|
|
void __maps_free(struct Map *);
|
|
void __maps_insert(struct Map *);
|
|
bool __maps_track(char *, size_t);
|
|
struct Map *__maps_alloc(void);
|
|
struct Map *__maps_floor(const char *);
|
|
void __maps_stack(char *, int, int, size_t, int, intptr_t);
|
|
int __maps_compare(const struct Tree *, const struct Tree *);
|
|
struct AddrSize __get_main_stack(void);
|
|
|
|
forceinline optimizespeed int __maps_search(const void *key,
|
|
const struct Tree *node) {
|
|
const char *addr = (const char *)key;
|
|
const struct Map *map = (const struct Map *)MAP_TREE_CONTAINER(node);
|
|
return (addr > map->addr) - (addr < map->addr);
|
|
}
|
|
|
|
static inline struct Map *__maps_next(struct Map *map) {
|
|
struct Tree *node;
|
|
if ((node = tree_next(&map->tree)))
|
|
return MAP_TREE_CONTAINER(node);
|
|
return 0;
|
|
}
|
|
|
|
static inline struct Map *__maps_first(void) {
|
|
struct Tree *node;
|
|
if ((node = tree_first(__maps.maps)))
|
|
return MAP_TREE_CONTAINER(node);
|
|
return 0;
|
|
}
|
|
|
|
COSMOPOLITAN_C_END_
|
|
#endif /* COSMOPOLITAN_MAPS_H_ */
|