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malloc: remove locking The issue manifests in fork: POSIX fork mandates that a fork'd process is created with a single thread. If a multithreaded program forks, and some thread was in malloc() when the fork() happened, then in the child the lock will be held but there will be no thread to release it. We assume the system malloc() must already know how to deal with this and is thread-safe, but it won't know about our custom spinlock. Judging that this is no longer necessary (the lock code was added 15 years ago) we remove it. Signed-off-by: Dan Cross <cross@gajendra.net>
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 1 e830a908 2005-11-06 devnull /*

 2 e830a908 2005-11-06 devnull  * These are here mainly so that I can link against

 3 e830a908 2005-11-06 devnull  * debugmalloc.c instead and not recompile the world.

 4 e830a908 2005-11-06 devnull  */

 5 e830a908 2005-11-06 devnull 

 6 e830a908 2005-11-06 devnull #include <u.h>

 7 e830a908 2005-11-06 devnull #define NOPLAN9DEFINES

 8 e830a908 2005-11-06 devnull #include <libc.h>

 9 e830a908 2005-11-06 devnull 

10 e830a908 2005-11-06 devnull void*

11 e830a908 2005-11-06 devnull p9malloc(ulong n)

12 e830a908 2005-11-06 devnull {

13 e830a908 2005-11-06 devnull 	void *v;

14 fa325e9b 2020-01-10 cross 

15 e830a908 2005-11-06 devnull 	if(n == 0)

16 e830a908 2005-11-06 devnull 		n++;

17 e830a908 2005-11-06 devnull 	v = malloc(n);

18 e830a908 2005-11-06 devnull 	print("p9malloc %lud => %p; pc %lux\n", n, v, getcallerpc(&n));

19 e830a908 2005-11-06 devnull 	return v;

20 e830a908 2005-11-06 devnull }

21 e830a908 2005-11-06 devnull 

22 e830a908 2005-11-06 devnull void

23 e830a908 2005-11-06 devnull p9free(void *v)

24 e830a908 2005-11-06 devnull {

25 e830a908 2005-11-06 devnull 	if(v == nil)

26 e830a908 2005-11-06 devnull 		return;

27 e830a908 2005-11-06 devnull 	print("p9free %p; pc %lux\n", v, getcallerpc(&v));

28 e830a908 2005-11-06 devnull 	free(v);

29 e830a908 2005-11-06 devnull }

30 e830a908 2005-11-06 devnull 

31 e830a908 2005-11-06 devnull void*

32 e830a908 2005-11-06 devnull p9calloc(ulong a, ulong b)

33 e830a908 2005-11-06 devnull {

34 e830a908 2005-11-06 devnull 	void *v;

35 fa325e9b 2020-01-10 cross 

36 e830a908 2005-11-06 devnull 	if(a*b == 0)

37 e830a908 2005-11-06 devnull 		a = b = 1;

38 e830a908 2005-11-06 devnull 

39 e830a908 2005-11-06 devnull 	v = calloc(a*b, 1);

40 e830a908 2005-11-06 devnull 	print("p9calloc %lud %lud => %p; pc %lux\n", a, b, v, getcallerpc(&a));

41 e830a908 2005-11-06 devnull 	return v;

42 e830a908 2005-11-06 devnull }

43 e830a908 2005-11-06 devnull 

44 e830a908 2005-11-06 devnull void*

45 e830a908 2005-11-06 devnull p9realloc(void *v, ulong n)

46 e830a908 2005-11-06 devnull {

47 e830a908 2005-11-06 devnull 	void *vv;

48 fa325e9b 2020-01-10 cross 

49 e830a908 2005-11-06 devnull 	vv = realloc(v, n);

50 e830a908 2005-11-06 devnull 	print("p9realloc %p %lud => %p; pc %lux\n", v, n, vv, getcallerpc(&v));

51 e830a908 2005-11-06 devnull 	return vv;

52 e830a908 2005-11-06 devnull }