view src/hotspot/share/runtime/threadCritical.hpp @ 52291:35a6956f4243

8209976: Improve iteration over non-JavaThreads Summary: Add NonJavaThread and move NamedThread iteration to new class. Reviewed-by: eosterlund, coleenp, rkennke
author kbarrett
date Tue, 28 Aug 2018 16:04:54 -0400
parents 71c04702a3d5
children 9807daeb47c4
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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 * accompanied this code).
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#include "memory/allocation.hpp"

// ThreadCritical is used to protect short non-blocking critical sections.
// This class must use no vm facilities that require initialization.
// It is used very early in the vm's initialization, in allocation
// code and other areas. ThreadCritical regions are reentrant.
// Due to race conditions during vm exit, some of the os level
// synchronization primitives may not be deallocated at exit. It
// is a good plan to implement the platform dependent sections of
// code with resources that are recoverable during process
// cleanup by the os. Calling the initialize method before use
// is also problematic, it is best to use preinitialized primitives
// if possible. As an example:
// mutex_t  mp  =  DEFAULTMUTEX;
// Also note that this class is declared as a StackObj to enforce
// block structured short locks. It cannot be declared a ResourceObj
// or CHeapObj, due to initialization issues.

class ThreadCritical : public StackObj {