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authorThomas Schwinge <thomas@codesourcery.com>2012-05-24 23:08:09 +0200
committerThomas Schwinge <thomas@codesourcery.com>2012-05-24 23:08:09 +0200
commit2910b7c5b1d55bc304344b584a25ea571a9075fb (patch)
treebfbfbc98d4c0e205d2726fa44170a16e8421855e /open_issues/glibc/t
parent35b719f54c96778f571984065579625bc9f15bf5 (diff)
Prepare toolchain/logs/master branch.
Diffstat (limited to 'open_issues/glibc/t')
-rw-r--r--open_issues/glibc/t/tls-threadvar.mdwn31
-rw-r--r--open_issues/glibc/t/tls.mdwn66
2 files changed, 0 insertions, 97 deletions
diff --git a/open_issues/glibc/t/tls-threadvar.mdwn b/open_issues/glibc/t/tls-threadvar.mdwn
deleted file mode 100644
index e72732ab..00000000
--- a/open_issues/glibc/t/tls-threadvar.mdwn
+++ /dev/null
@@ -1,31 +0,0 @@
-[[!meta copyright="Copyright © 2011, 2012 Free Software Foundation, Inc."]]
-
-[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
-id="license" text="Permission is granted to copy, distribute and/or modify this
-document under the terms of the GNU Free Documentation License, Version 1.2 or
-any later version published by the Free Software Foundation; with no Invariant
-Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license
-is included in the section entitled [[GNU Free Documentation
-License|/fdl]]."]]"""]]
-
-[[!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.
-
-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.
diff --git a/open_issues/glibc/t/tls.mdwn b/open_issues/glibc/t/tls.mdwn
deleted file mode 100644
index 14ef36e4..00000000
--- a/open_issues/glibc/t/tls.mdwn
+++ /dev/null
@@ -1,66 +0,0 @@
-[[!meta copyright="Copyright © 2011 Free Software Foundation, Inc."]]
-
-[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
-id="license" text="Permission is granted to copy, distribute and/or modify this
-document under the terms of the GNU Free Documentation License, Version 1.2 or
-any later version published by the Free Software Foundation; with no Invariant
-Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license
-is included in the section entitled [[GNU Free Documentation
-License|/fdl]]."]]"""]]
-
-[[!tag open_issue_glibc open_issue_libpthread]]
-
-# To Do
-
- * Discuss d2431f633e6139a62e1575ec18830f7e81160cf0 with Samuel.
-
- * `TLS_INIT_TP_EXPENSIVE` is unused; Hurd def. can be removed.
-
-
-# Documentation
-
-[[!taglink open_issue_documentation]]
-
- * IRC, freenode, #hurd, 2011-11-26
-
- <tschwinge> In glibc multiarch support (strcasecmp for i686 SSE3, etc.)
- there is access to memory via gs: -- this will need to be changed for
- us, right?
- <youpi> depends on the access
- <tschwinge> * `optimized strcasecmp and strncasecmp for x86-32`
- (multiarch),
- <tschwinge> 76e3966e9efc3808a9e7ad09121c5dfc1211c20b +
- <tschwinge> 6abf346582ba678f4850a88b4a5950593841df1d +
- <tschwinge> 5583a0862cf94f71cbcde91c4043a20af65facca. `gs`
- access.
- <youpi> + movl __libc_tsd_LOCALE@GOTNTPOFF(%ebx), %eax
- <youpi> that's handled by the linker fine
- <youpi> it's only the things held in the tcb_t structure which can pose
- problem
- <tschwinge> tcbhead_t?
- <tschwinge> I'm looking at this.
- <tschwinge> So, at gs:0, there is the TCB.
- <tschwinge> And we have the same layout as NPTL/Linux, just that we
- don't have as much data there as they have.
- <tschwinge> We're missing multiple_threads, sysinfo, sttack_guard,
- pointer_guard, gscope_flag, private_futex, __private_tm[5].
- <tschwinge> So, if one of these is referenced (be it my name or by
- numeric offset), this is invalid for us.
- <tschwinge> Anything else should work equivalently.
- <youpi> yes
- <youpi> usually the only numeric offset being used is 0
- <youpi> so it would simply not build
- <tschwinge> And the other offsers are generated via tcb-offsets.sym.
- <tschwinge> glibc's elf/stackguard-macros.h is wrong for us (but not
- used anywhere apart from elf/tst-stackguard1.c, I think).
- <tschwinge> __thread __locale_t __libc_tsd_LOCALE = &_nl_global_locale;
- -- this means that a __libc_tsd_LOCALE values will be in the TLS
- segment, and this is what is being accessed from the assembler code
- with %gs:__libc_tsd_LOCALE@NTPOFF, and the linker will resolve this.
- <youpi> yes
- <youpi> see in the nm output, the libc_tsd symbols
- <youpi> these provide the offsets
- <tschwinge> youpi: Thank you, I'm now understanding this part of TLS
- much better.
- <youpi> have you had a look at the tls.pdf from Uli ?
- <youpi> all the gory details are there :)