qbit/go
1
0
Fork 0
mirror of https://github.com/golang/go synced 2024-11-21 23:44:39 -07:00
Code Releases Activity

runtime: avoid malloc during malloc

Browse Source 
A fault during malloc might lead to the program's
first call to findfunc, which would in turn call malloc.
Don't do that.

Fixes #1777.

R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/5689047
This commit is contained in:
Russ Cox 2012-02-21 16:36:15 -05:00
parent d86213c371
commit fc7ed45b35
1 changed files with 10 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
src/pkg/runtime/symtab.c
View File

@ -437,13 +437,17 @@ runtime·findfunc(uintptr addr)
// (Before enabling the signal handler, // (Before enabling the signal handler,
// SetCPUProfileRate calls findfunc to trigger // SetCPUProfileRate calls findfunc to trigger
// the initialization outside the handler.) // the initialization outside the handler.)
if(runtime·atomicload(&funcinit) == 0) { // Avoid deadlock on fault during malloc
runtime·lock(&funclock); // by not calling buildfuncs if we're already in malloc.
if(funcinit == 0) { if(!m->mallocing && !m->gcing) {
buildfuncs(); if(runtime·atomicload(&funcinit) == 0) {
runtime·atomicstore(&funcinit, 1); runtime·lock(&funclock);
if(funcinit == 0) {
buildfuncs();
runtime·atomicstore(&funcinit, 1);
}
runtime·unlock(&funclock);
} }
runtime·unlock(&funclock);
} }
if(nfunc == 0) if(nfunc == 0)