On Wed, Aug 17, 2011 at 5:13 PM, Paolo Bonzini <pbonz...@redhat.com> wrote: > On 08/17/2011 09:51 AM, Stefan Hajnoczi wrote: >> >> Hmm...this is pretty ugly low-level stuff. glib provides portable TLS >> although I have found __thread significantly faster on Linux. >> >> I think our options are: >> 1. Use __thread and require recent gcc versions on Windows. Not as >> fast as native Windows TLS. >> 2. Implement our own TLS abstraction to use native TLS on each platform. >> 3. Use glib TLS (GStaticPrivate). It's slower than __thread on Linux >> but seems portable. >> >> Options 1 and 3 seem better because they do not involve us >> reimplementing yet more platform abstractions. > > True, but I'm afraid we'll need to reimplement more of them sooner or later, > for example for PI locks. QEMU's needs in this area are just more low level > than GLib's, though we could surely use glib's other threading primitives > such as the thread pool. > >> Do you know which Windows gcc versions support __thread and if it >> would be reasonable to require those versions? > > It's probably 4.3 and newer, or something like that.
No, GCC 3.3.6 manual already mentions it: http://gcc.gnu.org/onlinedocs/gcc-3.3.6/gcc/Thread_002dLocal.html#Thread_002dLocal
