From c93adfc170079a54965e939a5a4d57139cd714e1 Mon Sep 17 00:00:00 2001
From: normal <normal@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Sun, 8 Jul 2018 07:27:24 +0000
Subject: mjit: get rid of memory leak in pause+resume loop

pthread_atfork is not idempotent and repeatedly calling it
causes it to register the same hook repeatedly; leading to
unbound memory growth.

Ruby already has a (confusing-named) internal API for to call
in the forked child process: rb_thread_atfork
Call the MJIT child_after_fork hook inside that to prevent
unbound growth with the following loop:

    loop do
      RubyVM::MJIT.pause
      RubyVM::MJIT.resume
    end

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@63884 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 thread.c | 3 +++
 1 file changed, 3 insertions(+)

(limited to 'thread.c')

diff --git a/thread.c b/thread.c
index 360807b073..3943cf0fc6 100644
--- a/thread.c
+++ b/thread.c
@@ -4276,6 +4276,8 @@ terminate_atfork_i(rb_thread_t *th, const rb_thread_t *current_th)
     }
 }
 
+/* mjit.c */
+void mjit_child_after_fork(void);
 void
 rb_thread_atfork(void)
 {
@@ -4286,6 +4288,7 @@ rb_thread_atfork(void)
 
     /* We don't want reproduce CVE-2003-0900. */
     rb_reset_random_seed();
+    mjit_child_after_fork();
 }
 
 static void
-- 
cgit v1.2.3