On Sun, Mar 9, 2008 at 11:52 AM, Gilad Ben-Yossef <[EMAIL PROTECTED]> wrote: > Jamie Lokier wrote: > > Gilad Ben-Yossef wrote: > >> Glauber Costa wrote: > >>> This patch introduces a "thread_id" variable to CPUState. > >>> It's duty will be to hold the process, or more generally, thread > >>> id of the current executing cpu > >>> > >>> env->nb_watchpoints = 0; > >>> +#ifdef __WIN32 > >>> + env->thread_id = GetCurrentProcessId(); > >>> +#else > >>> + env->thread_id = getpid(); > >>> +#endif > >>> *penv = env; > >> hmm... maybe I'm missing something, but in Linux at least I think you > >> would prefer this to be gettid() rather then getpid as each CPU has it's > >> own thread, not a different process. > > > > On most platforms, getpid() returns the same value for all threads, so > > it's not useful as a thread id. > > Of course it does - this what POSIX says it should do (Linux 2.4 in > compliance not withstanding). Which is why I suggested to use on Linux > the non standard gettid() rather then getpid > > > > > On Linux, it depends which version of threads. The old package, > > LinuxThreads, has different getpid() for each thread. The current one, > > NPTL, has them all the same. > > > LinuxThreads behavior is wrong according to the POSIX standard. Of > course, nothing else was possible with 2.4 kernels, so this is not an > error on LinuxThreads coders part. > > > > > What you're supposed to do with pthreads in general is use pthread_self(). > > Unfortunately, AFAIK the opaque handle that pthread_self() returns is > not quite meaningless outside of the process whereas what the non > standard gettid() returns can actually be used to identify a thread from > "outside" the process, like the shell. >
Identifying a thread from the outside world is _exactly_ my intent here, so pthread_self won't do. I can easily write a wrapper to gettid() and use it. It would make the kvm specific patch not-necessary, which is good. The reason I used getpid in the first place, is that all raw qemu cpus are in the same process anyway. It's up to you, guys. -- Glauber Costa. "Free as in Freedom" http://glommer.net "The less confident you are, the more serious you have to act."