freebsd-dev/sys/i386/include/pcpu_aux.h
Konstantin Belousov a2a0f90654 Centralize __pcpu definitions.
Many extern struct pcpu <something>__pcpu declarations were
copied/pasted in sources.  The issue is that the definition is MD, but
it cannot be provided by machine/pcpu.h due to actual struct pcpu
defined in sys/pcpu.h later than the inclusion of machine/pcpu.h.
This forced the copying when other code needed direct access to
__pcpu.  There is no way around it, due to machine/pcpu.h supplying
part of struct pcpu fields.

To work around the problem, add a new machine/pcpu_aux.h header, which
should fill any needed MD definitions after struct pcpu definition is
completed. This allows to remove copies of __pcpu spread around the
source.  Also on x86 it makes it possible to remove work arounds like
OFFSETOF_CURTHREAD or clang specific warnings supressions.

Reported and tested by:	lwhsu, bcran
Reviewed by:	imp, markj (previous version)
Discussed with:	jhb
Sponsored by:	The FreeBSD Foundation
Differential revision:	https://reviews.freebsd.org/D21418
2019-08-29 07:25:27 +00:00

72 lines
2.3 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2019 The FreeBSD Foundation
*
* This software was developed by Konstantin Belousov <kib@FreeBSD.org>
* under sponsorship from the FreeBSD Foundation.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
*
* $FreeBSD$
*/
#ifndef _MACHINE_PCPU_AUX_H_
#define _MACHINE_PCPU_AUX_H_
#ifndef _KERNEL
#error "Not for userspace"
#endif
#ifndef _SYS_PCPU_H_
#error "Do not include machine/pcpu_aux.h directly"
#endif
/* Required for counters(9) to work on x86. */
_Static_assert(sizeof(struct pcpu) == UMA_PCPU_ALLOC_SIZE, "fix pcpu size");
extern struct pcpu __pcpu[];
static __inline __pure2 struct thread *
__curthread(void)
{
struct thread *td;
__asm("movl %%fs:%1,%0" : "=r" (td)
: "m" (*(char *)offsetof(struct pcpu, pc_curthread)));
return (td);
}
#define curthread (__curthread())
static __inline __pure2 struct pcb *
__curpcb(void)
{
struct pcb *pcb;
__asm("movl %%fs:%1,%0" : "=r" (pcb)
: "m" (*(char *)offsetof(struct pcpu, pc_curpcb)));
return (pcb);
}
#define curpcb (__curpcb())
#endif /* _MACHINE_PCPU_AUX_H_ */