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>
Having received another series of whitespace patches I decided to do this
once and for all rather than dealing with this kind of patches trickling
in forever.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Most supported systems currently hardwire cpu_has_dsp to 0, so we also
can disable support for cpu_has_dsp2 resulting in a slightly smaller
kernel.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Loongson 2 does not have dcache aliases when is using 16k pages. and the
And because Loongson 2 doesn't do SMP , cpu_icache_snoops_remote_store does
not matter here.
Signed-off-by: Zhang Le <r0bertz@gentoo.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
To make source code of loongson sharable to the machines(such as gdium)
made by the other companies, we rename arch/mips/lemote to
arch/mips/loongson, asm/mach-lemote to asm/mach-loongson, and rename lm2e
to the name of the machine: fuloong-2e. accordingly, FULONG are renamed to
FULOONG2E to make it distinguishable to the future FULOONG2F. and also,
some other relative tuning is needed.
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
