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| author | Robert Morris <rtm@csail.mit.edu> | 2020-11-05 07:32:10 -0500 |
|---|---|---|
| committer | Frans Kaashoek <kaashoek@mit.edu> | 2020-11-05 19:50:46 -0500 |
| commit | ba8d9f4808bd2c59df42a6615920a22e3735c359 (patch) | |
| tree | a2b89fe071e83d7e9b6d49d582bee8301e40dc9c /kernel/proc.c | |
| parent | 47323c97cf6bcf5e238c518762ba048e8795f57d (diff) | |
| download | xv6-labs-2022-ba8d9f4808bd2c59df42a6615920a22e3735c359.tar.xz xv6-labs-2022-ba8d9f4808bd2c59df42a6615920a22e3735c359.zip | |
don't over-lock in exit()
Diffstat (limited to 'kernel/proc.c')
| -rw-r--r-- | kernel/proc.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/kernel/proc.c b/kernel/proc.c index 54c965d..bd77dad 100644 --- a/kernel/proc.c +++ b/kernel/proc.c @@ -358,14 +358,14 @@ exit(int status) p->cwd = 0; acquire(&proc_tree_lock); - - acquire(&p->lock); // Give any children to init. reparent(p); // Parent might be sleeping in wait(). wakeup(p->parent); + + acquire(&p->lock); p->xstate = status; p->state = ZOMBIE; @@ -393,7 +393,9 @@ wait(uint64 addr) havekids = 0; for(np = proc; np < &proc[NPROC]; np++){ if(np->parent == p){ + // make sure the child isn't still in exit() or swtch(). acquire(&np->lock); + havekids = 1; if(np->state == ZOMBIE){ // Found one. |