freebsd-skq/sys/arm64/include/proc.h
alc 2a4c328a15 Utilize ASIDs to reduce both the direct and indirect costs of context
switching.  The indirect costs being unnecessary TLB misses that are
incurred when ASIDs are not used.  In fact, currently, when we perform a
context switch on one processor, we issue a broadcast TLB invalidation that
flushes the TLB contents on every processor.

Mark all user-space ("ttbr0") page table entries with the non-global flag so
that they are cached in the TLB under their ASID.

Correct an error in pmap_pinit0().  The pointer to the root of the page
table was being initialized to the root of the kernel-space page table
rather than a user-space page table.  However, the root of the page table
that was being cached in process 0's md_l0addr field correctly pointed to a
user-space page table.  As long as ASIDs weren't being used, this was
harmless, except that it led to some unnecessary page table switches in
pmap_switch().  Specifically, other kernel processes besides process 0 would
have their md_l0addr field set to the root of the kernel-space page table,
and so pmap_switch() would actually change page tables when switching
between process 0 and other kernel processes.

Implement a workaround for Cavium erratum 27456 affecting ThunderX machines.
(I would like to thank andrew@ for providing the code to detect the affected
machines.)

Address integer overflow in the definition of TCR_ASID_16.

Setup TCR according to the PARange and ASIDBits fields from
ID_AA64MMFR0_EL1.  Previously, TCR_ASID_16 was unconditionally set.

Modify build_l1_block_pagetable so that lower attributes, such as ATTR_nG,
can be specified as a parameter.

Eliminate some unused code.

Earlier versions were tested to varying degrees by: andrew, emaste, markj

MFC after:	3 weeks
Differential Revision:	https://reviews.freebsd.org/D21922
2019-11-03 17:45:30 +00:00

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2.4 KiB
C

/*-
* Copyright (c) 1991 Regents of the University of California.
* 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. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
* from: @(#)proc.h 7.1 (Berkeley) 5/15/91
* from: FreeBSD: src/sys/i386/include/proc.h,v 1.11 2001/06/29
* $FreeBSD$
*/
#ifndef _MACHINE_PROC_H_
#define _MACHINE_PROC_H_
struct mdthread {
int md_spinlock_count; /* (k) */
register_t md_saved_daif; /* (k) */
};
struct mdproc {
long md_dummy;
};
#define KINFO_PROC_SIZE 1088
#define KINFO_PROC32_SIZE 816
#define MAXARGS 8
struct syscall_args {
u_int code;
struct sysent *callp;
register_t args[MAXARGS];
int narg;
};
#ifdef _KERNEL
#include <machine/pcb.h>
#define GET_STACK_USAGE(total, used) do { \
struct thread *td = curthread; \
(total) = td->td_kstack_pages * PAGE_SIZE - sizeof(struct pcb); \
(used) = (char *)td->td_kstack + \
td->td_kstack_pages * PAGE_SIZE - \
(char *)&td; \
} while (0)
#endif
#endif /* !_MACHINE_PROC_H_ */