linux_dsm_epyc7002/arch/mips/include/asm/mach-loongson/cpu-feature-overrides.h
Huacai Chen 8759934e2b MIPS: Build uasm-generated code only once to avoid CPU Hotplug problem
This and the next patch resolve memory corruption problems while CPU
hotplug. Without these patches, memory corruption can triggered easily
as below:

On a quad-core MIPS platform, use "spawn" of UnixBench-5.1.3 (http://
code.google.com/p/byte-unixbench/) and a CPU hotplug script like this
(hotplug.sh):
while true; do
echo 0 >/sys/devices/system/cpu/cpu1/online
echo 0 >/sys/devices/system/cpu/cpu2/online
echo 0 >/sys/devices/system/cpu/cpu3/online
sleep 1
echo 1 >/sys/devices/system/cpu/cpu1/online
echo 1 >/sys/devices/system/cpu/cpu2/online
echo 1 >/sys/devices/system/cpu/cpu3/online
sleep 1
done

Run "hotplug.sh" and then run "spawn 10000", spawn will get segfault
after a few minutes.

This patch:
Currently, clear_page()/copy_page() are generated by Micro-assembler
dynamically. But they are unavailable until uasm_resolve_relocs() has
finished because jump labels are illegal before that. Since these
functions are shared by every CPU, we only call build_clear_page()/
build_copy_page() only once at boot time. Without this patch, programs
will get random memory corruption (segmentation fault, bus error, etc.)
while CPU Hotplug (e.g. one CPU is using clear_page() while another is
generating it in cpu_cache_init()).

For similar reasons we modify build_tlb_refill_handler()'s invocation.

V2:
1, Rework the code to make CPU#0 can be online/offline.
2, Introduce cpu_has_local_ebase feature since some types of MIPS CPU
   need a per-CPU tlb_refill_handler().

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Hongbing Hu <huhb@lemote.com>
Acked-by: David Daney <david.daney@cavium.com>
Patchwork: http://patchwork.linux-mips.org/patch/4994/
Acked-by: John Crispin <blogic@openwrt.org>
2013-05-08 01:19:06 +02:00

63 lines
1.7 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2009 Wu Zhangjin <wuzhangjin@gmail.com>
* Copyright (C) 2009 Philippe Vachon <philippe@cowpig.ca>
* Copyright (C) 2009 Zhang Le <r0bertz@gentoo.org>
*
* reference: /proc/cpuinfo,
* arch/mips/kernel/cpu-probe.c(cpu_probe_legacy),
* arch/mips/kernel/proc.c(show_cpuinfo),
* loongson2f user manual.
*/
#ifndef __ASM_MACH_LOONGSON_CPU_FEATURE_OVERRIDES_H
#define __ASM_MACH_LOONGSON_CPU_FEATURE_OVERRIDES_H
#define cpu_dcache_line_size() 32
#define cpu_icache_line_size() 32
#define cpu_scache_line_size() 32
#define cpu_has_32fpr 1
#define cpu_has_3k_cache 0
#define cpu_has_4k_cache 1
#define cpu_has_4kex 1
#define cpu_has_64bits 1
#define cpu_has_cache_cdex_p 0
#define cpu_has_cache_cdex_s 0
#define cpu_has_counter 1
#define cpu_has_dc_aliases (PAGE_SIZE < 0x4000)
#define cpu_has_divec 0
#define cpu_has_dsp 0
#define cpu_has_dsp2 0
#define cpu_has_ejtag 0
#define cpu_has_fpu 1
#define cpu_has_ic_fills_f_dc 0
#define cpu_has_inclusive_pcaches 1
#define cpu_has_llsc 1
#define cpu_has_mcheck 0
#define cpu_has_mdmx 0
#define cpu_has_mips16 0
#define cpu_has_mips32r1 0
#define cpu_has_mips32r2 0
#define cpu_has_mips3d 0
#define cpu_has_mips64r1 0
#define cpu_has_mips64r2 0
#define cpu_has_mipsmt 0
#define cpu_has_prefetch 0
#define cpu_has_smartmips 0
#define cpu_has_tlb 1
#define cpu_has_tx39_cache 0
#define cpu_has_userlocal 0
#define cpu_has_vce 0
#define cpu_has_veic 0
#define cpu_has_vint 0
#define cpu_has_vtag_icache 0
#define cpu_has_watch 1
#define cpu_has_local_ebase 0
#endif /* __ASM_MACH_LOONGSON_CPU_FEATURE_OVERRIDES_H */