freebsd-dev/lib/libthr/arch/powerpc/include/pthread_md.h
Andrew Turner 20fe2c9465 Merge all the copies of _tcb_ctor and _tcb_dtor.
The amd64, i386, and sparc64 versions were identical, with the one
difference where the former two used inline asm instead of _tcb_get. I
have compared the function before and after replacing the asm with _tcb_get
and found the object files to be identical.

The arm, mips, and powerpc versions were almost identical. The only
difference was the powerpc version used an alignment of 1 where arm and
mips used 16. As this is an increase in alignment is will be safe.

Along with this arm, mips, and powerpc all passed, when initial was true,
the value returned from _tcb_get as the first argument to
_rtld_allocate_tls. This would then return this pointer back to the caller.
We can remove these extra calls by checking if initial is set and setting
the thread control block directly. As this is what the sparc64 code does
we can use it directly.

As after these observations all the architectures can now have identical
code we can merge them into a common file.

Differential Revision:	https://reviews.freebsd.org/D1556
Reviewed by:	kib
Sponsored by:	The FreeBSD Foundation
2015-01-21 16:41:05 +00:00

94 lines
2.6 KiB
C

/*
* Copyright 2004 by Peter Grehan. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
/*
* Machine-dependent thread prototypes/definitions.
*/
#ifndef _PTHREAD_MD_H_
#define _PTHREAD_MD_H_
#include <stddef.h>
#include <sys/types.h>
#define CPU_SPINWAIT
#define DTV_OFFSET offsetof(struct tcb, tcb_dtv)
#ifdef __powerpc64__
#define TP_OFFSET 0x7010
#else
#define TP_OFFSET 0x7008
#endif
/*
* Variant I tcb. The structure layout is fixed, don't blindly
* change it.
* %r2 (32-bit) or %r13 (64-bit) points to end of the structure.
*/
struct tcb {
void *tcb_dtv;
struct pthread *tcb_thread;
};
static __inline void
_tcb_set(struct tcb *tcb)
{
#ifdef __powerpc64__
__asm __volatile("mr 13,%0" ::
"r"((uint8_t *)tcb + TP_OFFSET));
#else
__asm __volatile("mr 2,%0" ::
"r"((uint8_t *)tcb + TP_OFFSET));
#endif
}
static __inline struct tcb *
_tcb_get(void)
{
register uint8_t *_tp;
#ifdef __powerpc64__
__asm __volatile("mr %0,13" : "=r"(_tp));
#else
__asm __volatile("mr %0,2" : "=r"(_tp));
#endif
return ((struct tcb *)(_tp - TP_OFFSET));
}
extern struct pthread *_thr_initial;
static __inline struct pthread *
_get_curthread(void)
{
if (_thr_initial)
return (_tcb_get()->tcb_thread);
return (NULL);
}
#endif /* _PTHREAD_MD_H_ */