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Improve lock hierarchy

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- NetBSD no longer needs a spin lock to create semaphores
- Windows fork() now locks process manager in correct order
This commit is contained in:
Justine Tunney 2024-07-24 15:55:57 -07:00
parent 7ba9a73840
commit d3a13e8d70
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GPG key ID: BE714B4575D6E328
14 changed files with 73 additions and 71 deletions
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33
libc/proc/proc.c
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@ -30,7 +30,6 @@
#include "libc/intrin/strace.h"
#include "libc/intrin/weaken.h"
#include "libc/mem/leaks.h"
#include "libc/mem/mem.h"
#include "libc/nt/accounting.h"
#include "libc/nt/enum/processaccess.h"
#include "libc/nt/enum/processcreationflags.h"
@ -45,12 +44,16 @@
#include "libc/nt/synchronization.h"
#include "libc/nt/thread.h"
#include "libc/proc/proc.internal.h"
#include "libc/runtime/runtime.h"
#include "libc/str/str.h"
#include "libc/sysv/consts/map.h"
#include "libc/sysv/consts/prot.h"
#include "libc/sysv/consts/sa.h"
#include "libc/sysv/consts/sicode.h"
#include "libc/sysv/consts/sig.h"
#include "libc/sysv/errfuns.h"
#include "libc/thread/tls.h"
#include "third_party/nsync/mu.h"
#ifdef __x86_64__
/**
@ -273,27 +276,21 @@ textwindows void __proc_wipe(void) {
textwindows struct Proc *__proc_new(void) {
struct Dll *e;
struct Proc *proc = 0;
// fork() + wait() don't depend on malloc() so neither shall we
if (__proc.allocated < ARRAYLEN(__proc.pool)) {
proc = __proc.pool + __proc.allocated++;
} else {
if ((e = dll_first(__proc.free))) {
proc = PROC_CONTAINER(e);
dll_remove(&__proc.free, &proc->elem);
}
if (!proc) {
if (_weaken(malloc)) {
proc = may_leak(_weaken(malloc)(sizeof(struct Proc)));
} else {
enomem();
return 0;
}
}
if ((e = dll_first(__proc.free))) {
proc = PROC_CONTAINER(e);
dll_remove(&__proc.free, &proc->elem);
}
if (proc) {
bzero(proc, sizeof(*proc));
dll_init(&proc->elem);
} else {
proc = mmap(0, sizeof(struct Proc), PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (proc == MAP_FAILED) {
enomem();
return 0;
}
}
dll_init(&proc->elem);
return proc;
}