osch/lua-threading-playground

Multi threading test cases crashing under LuaJIT

Test Cases for multi threading Lua

This repository contains two test cases that are showing crashes using LuaJIT when native lua packages are loaded in other threads.

Tests

• test01 - uses lua-llthreads2 as threading library and lpeg as native lua package

• test02 - uses luaproc as threading library and luafilesystem as native lua package

Test Results for both tests:

• no crash with Lua 5.1, 5.2 and 5.3
• crash with LuaJIT 2.0 and 2.1 under Linux
• see Travis CI Results for result details

*** Error in `lua': double free or corruption (fasttop): 0x00007f43400008c0 ***

test01

    local llthreads = require("llthreads2.ex")
    
    local THREAD_COUNT = 1000
    
    local thread_code = function()
    
        local lpeg = require("lpeg") -- no crash without this line
    
        local loadstring = loadstring or load
        local x = 1
        while x < 1000 do 
            x = x + 1 
            -- do some work
            assert(x == loadstring("return "..x)())
        end
    end
    
    local threads = {}
    
    for i = 1, THREAD_COUNT do 
        local thread = llthreads.new(thread_code)
        threads[i] = thread
        thread:start()
    end
    
    for i = 1, THREAD_COUNT do 
        local thread = threads[i]
        thread:join()
    end
    print("OK.")

test02

    local luaproc = require("luaproc")
    
    local THREAD_COUNT = 1000
    luaproc.setnumworkers(THREAD_COUNT)
    
    local thread_code = function()
    
        local lpeg = require("lfs") -- no crash without this line
    
        local loadstring = loadstring or load
        local x = 1
        while x < 1000 do 
            x = x + 1 
            -- do some work
            assert(x == loadstring("return "..x)())
        end
    end
    
    local threads = {}
    
    for i = 1, THREAD_COUNT do 
        local thread = luaproc.newproc(thread_code)
        threads[i] = thread
    end
    
    luaproc.wait()
    
    print("OK.\n")