How is thread local storage (__thread) implemented on LInux?

Posted by anon on Stack Overflow See other posts from Stack Overflow or by anon
Published on 2010-03-17T03:16:04Z Indexed on 2010/03/17 3:21 UTC
Read the original article Hit count: 284

Filed under:

thread-local-storage

|

multi-threading

__thread Foo foo;

How is "foo" actually resolved? Does the compiler silently replace every instance of "foo" with a function call? Is "foo" stored somewhere relative to the bottom of the stack, and the compiler stores this as "hey, for each thread, have this space near the bottom of the stack, and foo is stored as "offset x from bottom of stack"" ?

Insights please.

© Stack Overflow or respective owner

Related posts about thread-local-storage

Thread-local storage segfaults on NetBSD only?

as seen on Stack Overflow - Search for 'Stack Overflow'
Trying to run a C++ program, I get segmentation faults which appear to be specific to NetBSD. Bert Hubert wrote the simple test program (at the end of this message) and, indeed, it crashes only on NetBSD. % uname -a NetBSD golgoth 5.0.1 NetBSD 5.0.1 (GENERIC) #0: Thu Oct 1 15:46:16 CEST 2009 +stephane@golgoth:/usr/obj/sys/arch/i386/compile/GENERIC… >>> More
Linux's thread local storage implementation

as seen on Stack Overflow - Search for 'Stack Overflow'
__thread Foo foo; How is "foo" actually resolved? Does the compiler silently replace every instance of "foo" with a function call? Is "foo" stored somewhere relative to the bottom of the stack, and the compiler stores this as "hey, for each thread, have this space near the bottom of the stack, and… >>> More
Why is thread local storage so slow?

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm working on a custom mark-release style memory allocator for the D programming language that works by allocating from thread-local regions. It seems that the thread local storage bottleneck is causing a huge (~50%) slowdown in allocating memory from these regions compared to an otherwise identical… >>> More
Thread Local Storage and local method variables

as seen on Stack Overflow - Search for 'Stack Overflow'
In c#, each thread has its own stack space. If this is the case, why is the following code not thread-safe? (It is stated that this code is thread-safe on this post: Locking in C# class Foo { private int count = 0; public void TrySomething() { count++; } } As… >>> More
Thread local storage with __declspec(thread) fails in C++/CLI

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm working on a project where we mix .NET code and native C++ code via a C++/CLI layer. In this solution I want to use Thread Local Storage via the __declspec(thread) declaration: __declspec(thread) int lastId = 0; However, at the first access of the variable, I get a NullReferenceException. To… >>> More

Related posts about multi-threading

what are the difficulties of operating system multithreading?

as seen on Stack Overflow - Search for 'Stack Overflow'
I am reading a book that compares two ways of implementing threads, Middleware Threads and OS Threads. I have a question about these sentences: "A difficulty of operating system multithreading, however, is performance overhead. Since it is the operating system that is involved in switching threads… >>> More
Multithreading recommendation based on program description

as seen on Stack Overflow - Search for 'Stack Overflow'
I would like to describe some specifics of my program and get feedback on what the best multithreading model to use would be most applicable. I've spent a lot of time now reading on ThreadPool, Threads, Producer/Consumer, etc. and have yet to come to solid conclusions. I have a list of files (all… >>> More
Multi-Threading - Cleanup strategy at program end

as seen on Stack Overflow - Search for 'Stack Overflow'
What is the best way to finish a multi-threaded application in a clean way? I am starting several socket connections from the main thread in seperate sockets and wait until the end of my business day in the main thread and use currently System.Environment.Exit(0) to terminate it. This leads to an… >>> More
Basic Java Multi-Threading Question

as seen on Stack Overflow - Search for 'Stack Overflow'
When an object is instantiated in Java, is it bound to the thread that instantiated in? Because when I anonymously implement an interface in one thread, and pass it to another thread to be run, all of its methods are run in the original thread. If they are bound to their creation thread, is there… >>> More
Multi-Threading in .NET

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi all.. I wrote this program, that is supposed to read about 5000 email address and send an pre-defined html mail. I am using the background worker component. The problem is this: I have wired up the method who is supposed to send the mail. But I am calling another method that is supposed to append… >>> More