qemu/include/exec/tb-hash.h
Markus Armbruster ec150c7e09 include: Make headers more self-contained
Back in 2016, we discussed[1] rules for headers, and these were
generally liked:

1. Have a carefully curated header that's included everywhere first.  We
   got that already thanks to Peter: osdep.h.

2. Headers should normally include everything they need beyond osdep.h.
   If exceptions are needed for some reason, they must be documented in
   the header.  If all that's needed from a header is typedefs, put
   those into qemu/typedefs.h instead of including the header.

3. Cyclic inclusion is forbidden.

This patch gets include/ closer to obeying 2.

It's actually extracted from my "[RFC] Baby steps towards saner
headers" series[2], which demonstrates a possible path towards
checking 2 automatically.  It passes the RFC test there.

[1] Message-ID: <87h9g8j57d.fsf@blackfin.pond.sub.org>
    https://lists.nongnu.org/archive/html/qemu-devel/2016-03/msg03345.html
[2] Message-Id: <20190711122827.18970-1-armbru@redhat.com>
    https://lists.nongnu.org/archive/html/qemu-devel/2019-07/msg02715.html

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190812052359.30071-2-armbru@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-08-16 13:31:51 +02:00

70 lines
2.3 KiB
C

/*
* internal execution defines for qemu
*
* Copyright (c) 2003 Fabrice Bellard
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#ifndef EXEC_TB_HASH_H
#define EXEC_TB_HASH_H
#include "exec/cpu-defs.h"
#include "exec/exec-all.h"
#include "qemu/xxhash.h"
#ifdef CONFIG_SOFTMMU
/* Only the bottom TB_JMP_PAGE_BITS of the jump cache hash bits vary for
addresses on the same page. The top bits are the same. This allows
TLB invalidation to quickly clear a subset of the hash table. */
#define TB_JMP_PAGE_BITS (TB_JMP_CACHE_BITS / 2)
#define TB_JMP_PAGE_SIZE (1 << TB_JMP_PAGE_BITS)
#define TB_JMP_ADDR_MASK (TB_JMP_PAGE_SIZE - 1)
#define TB_JMP_PAGE_MASK (TB_JMP_CACHE_SIZE - TB_JMP_PAGE_SIZE)
static inline unsigned int tb_jmp_cache_hash_page(target_ulong pc)
{
target_ulong tmp;
tmp = pc ^ (pc >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS));
return (tmp >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS)) & TB_JMP_PAGE_MASK;
}
static inline unsigned int tb_jmp_cache_hash_func(target_ulong pc)
{
target_ulong tmp;
tmp = pc ^ (pc >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS));
return (((tmp >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS)) & TB_JMP_PAGE_MASK)
| (tmp & TB_JMP_ADDR_MASK));
}
#else
/* In user-mode we can get better hashing because we do not have a TLB */
static inline unsigned int tb_jmp_cache_hash_func(target_ulong pc)
{
return (pc ^ (pc >> TB_JMP_CACHE_BITS)) & (TB_JMP_CACHE_SIZE - 1);
}
#endif /* CONFIG_SOFTMMU */
static inline
uint32_t tb_hash_func(tb_page_addr_t phys_pc, target_ulong pc, uint32_t flags,
uint32_t cf_mask, uint32_t trace_vcpu_dstate)
{
return qemu_xxhash7(phys_pc, pc, flags, cf_mask, trace_vcpu_dstate);
}
#endif