Commit Graph

10 Commits

Author SHA1 Message Date
Dimitry Andric
b34d83a709 The TCB_GET32() and TCB_GET64() macros in the i386 and amd64-specific
versions of pthread_md.h have a special case of dereferencing a null
pointer.  Clang warns about this with:

In file included from lib/libthr/arch/i386/i386/pthread_md.c:36:
lib/libthr/arch/i386/include/pthread_md.h:96:10: error: indirection of non-volatile null pointer will be deleted, not trap [-Werror,-Wnull-dereference]
        return (TCB_GET32(tcb_self));
                ^~~~~~~~~~~~~~~~~~~
lib/libthr/arch/i386/include/pthread_md.h:73:13: note: expanded from:
            : "m" (*(u_int *)(__tcb_offset(name))));            \
                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
lib/libthr/arch/i386/include/pthread_md.h:96:10: note: consider using __builtin_trap() or qualifying pointer with 'volatile'

Since this indirection is done relative to the fs or gs segment, to
retrieve thread-specific data, it is an exception to the rule.

Therefore, add a volatile qualifier to tell the compiler we really want
to dereference a zero address.

MFC after:	1 week
2011-12-15 19:42:25 +00:00
Konstantin Belousov
6c69d05232 Add section .note.GNU-stack for assembly files used by 386 and amd64. 2011-01-07 16:09:33 +00:00
Warner Losh
10f3ae5899 Merge from tbemd, with a small amount of rework:
For all libthr contexts, use ${MACHINE_CPUARCH}
for all libc contexts, use ${MACHINE_ARCH} if it exists, otherwise use
${MACHINE_CPUARCH}
Move some common code up a layer (the .PATH statement was the same in
all the arch submakefiles).

# Hope she hasn't busted powerpc64 with this...
2010-09-13 01:43:10 +00:00
David Xu
d6e0eb0a48 Replace function _umtx_op with _umtx_op_err, the later function directly
returns errno, because errno can be mucked by user's signal handler and
most of pthread api heavily depends on errno to be correct, this change
should improve stability of the thread library.
2008-04-02 07:41:25 +00:00
David E. O'Brien
a2c4cd4549 style.Makefile(5) 2008-02-13 05:25:43 +00:00
David Xu
d99f6dac14 - Remove variable _thr_scope_system, all threads are system scope.
- Rename _thr_smp_cpus to boolean variable _thr_is_smp.
- Define CPU_SPINWAIT macro for each arch, only X86 supports it.
2006-12-15 11:52:01 +00:00
David Xu
b7e118b1e0 Remove declaration of _thr_initial from MD header file, it is no longer
needed.
2006-04-04 03:35:26 +00:00
David Xu
7bd761788d Simplify _get_curthread() and _tcb_ctor because libc and rtld now
already allocate thread pointer space in tls block for initial thread.
Only i386 and amd64 have been done, others still have to be tested.
2006-04-04 03:26:06 +00:00
David Xu
a091d823ad Import my recent 1:1 threading working. some features improved includes:
1. fast simple type mutex.
 2. __thread tls works.
 3. asynchronous cancellation works ( using signal ).
 4. thread synchronization is fully based on umtx, mainly, condition
    variable and other synchronization objects were rewritten by using
    umtx directly. those objects can be shared between processes via
    shared memory, it has to change ABI which does not happen yet.
 5. default stack size is increased to 1M on 32 bits platform, 2M for
    64 bits platform.
As the result, some mysql super-smack benchmarks show performance is
improved massivly.

Okayed by: jeff, mtm, rwatson, scottl
2005-04-02 01:20:00 +00:00
David Xu
f5eb80a9d3 Add AMD64 support code. 2004-08-19 23:41:12 +00:00