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[[!tag open_issue_glibc open_issue_libpthread]]

This basically means to get rid of `sysdeps/mach/hurd/bits/libc-tsd.h` (and
thus the `_HURD_THREADVAR_*`/`_hurd_threadvar_location` interface), and
directly use `__thread` instead.

[[!toc]]


# IRC, freenode, #hurd, 2011-10-23

    <tschwinge> youpi: If we want to replace threadvars with TLS, there is one
      problem: the threadvars interface is publically exported:
      /usr/include/hurd/threadvar.h.
    <tschwinge> youpi: But I am somewhat inclined to say that the only user of
      this is libthreads/libpthread.  Do you think differently?
    <youpi> tschwinge: that's very probable
    <youpi> so I think we can just drop it
    <youpi> (people should use TLS anyway)

[[libpthread_set_stack_size]].

After this has been done, probably the whole `__libc_tsd_*` stuff can be
dropped altogether, and `__thread` directly be used in glibc.


# IRC, freenode, #hurd, 2012-08-07

    <tschwinge> r5219: Update libpthread patch to replace threadvar with tls
      for pthread_self
    <tschwinge> r5224: revert r5219 too, it's not ready either
    <youpi> as the changelog says, the __thread revertal is because it posed
      problems
    <youpi> and I just didn't have any time to check them while the freeze was
      so close
    <tschwinge> OK.  What kind of problems?  Should it be reverted upstream,
      too?
    <youpi> I don't remember exactly
    <youpi> it should just be fixed
    <youpi> we can revert it upstream, but it'd be good that we manage to
      progress, at some point...
    <tschwinge> Of course -- however as long as we don't know what kind of
      problem, it is a bit difficult.  ;-)
    <youpi> since I didn't left a note, it was most probably a mere glibc run,
      or boot with the patched libpthread
    <youpi> *testsuite run
    <tschwinge> OK.
    <tschwinge> The libpthread testsuite doesn't show any issues with that
      patch applied, though.  But I didn'T test anything else.
    <tschwinge> youpi: Also, you have probably seen my glibc __thread errno
      email -- rmcgrath wanted to find some time this week to comment/help, and
      I take it you don't have any immediate comments to that issue?
    <youpi> I saw the mails, but didn't investigate at all

[[!message-id "878vdyqht3.fsf@kepler.schwinge.homeip.net"]].


# IRC, freenode, #hurd, 2013-07-08

    <youpi> tschwinge: apparently there were a lot of changes missing in the
      threadvars branch I had commited long time ago
    <youpi> I'm gathering things
    <tschwinge> youpi: t/tls-threadvar you mean?
    <youpi> yes
    <youpi> tschwinge: yes, there were a lot other occurences of threadvars
      stuff in various places
    <youpi> I'm building libc again, and will see what issue would remain


## IRC, freenode, #hurd, 2013-07-12

    <youpi> braunr: about the per-thread ports, there is also the mig reply
      port
    <youpi> (stored in _HURD_THREADVAR_MIG_REPLY)


## IRC, freenode, #hurd, 2013-07-15

    <braunr> and with the branch youpi pushed where he removes threadvars, it
      shouldn't get "too" hard
    <braunr> (save for the tricky bugs you may encounter)
    <youpi> well, that branch is not working yet


## IRC, OFTC, #debian-hurd, 2013-09-22

    <youpi> I'm currently tracking bugs with my threadvars changes
    <youpi> some of them seem fine, others, not
    <youpi> of course the most complex ones are the most probable culprits for
      the issues I'm getting
    <youpi> fortunately they're after the process bootstrap
    <youpi> so basically that works
    <youpi> just a few dozen tests fail
    <youpi> mostly about loading .so  or raising signals
    <youpi> dlopen("bug-dlsym1-lib1.so"): bug-dlsym1-lib1.so: cannot open
      shared object file: Function not implemented
    <youpi> after having changed errno a bit
    <youpi> doesn't that look odd ? :)
    <youpi> good, I found an issue with the sigstate
    <youpi> now running testsuite again, to see whether there are other issues
      with it :)
    <youpi> s/sigstate/reply_port/ actually


## IRC, OFTC, #debian-hurd, 2013-09-23

    <youpi> yay, errno threadvar conversion success


## IRC, OFTC, #debian-hurd, 2013-10-05

    <gg0_> youpi: any ETA for tls?
    <youpi> gg0_: one can't have an ETA for bugfixing
    <gg0_> i don't call them bugs if there's something missing to implement btw
    <youpi> no, here it's bugs
    <youpi> the implementation is already in the glibc branches in our
      repository
    <youpi> it just makes some important regressions


## IRC, OFTC, #debian-hurd, 2013-10-07

    <youpi> about tls, I've made some "progress": now I'm wondering how raise()
      has ever been working before :)


## IRC, OFTC, #debian-hurd, 2013-10-15

    <youpi> good, reply_port tls  is now ok
    <youpi> last but not least, sigstate


## IRC, OFTC, #debian-hurd, 2013-10-21

    <youpi> started testsuite with threadvars dropped completely
    <youpi> so far so good


## IRC, OFTC, #debian-hurd, 2013-10-24

    <youpi> ok, hurd boots with full-tls libc, no threadvars at all any more
    <gg0> \o/
    <gg0> good bye threadvars bugs, welcome tls ones ;)
    <youpi> now I need to check that threads can really use another stack :)