Pingfan Liu and Palmer Dabbelt
f40fe31c01
riscv: cpu-hotplug: clear cpu from numa map when teardown
...
There is numa_add_cpu() when cpus online, accordingly, there should be
numa_remove_cpu() when cpus offline.
Signed-off-by: Pingfan Liu <kernelfans@gmail.com >
Fixes: 4f0e8eef77 ("riscv: Add numa support for riscv64 platform")
Cc: stable@vger.kernel.org
[Palmer: Add missing NUMA include]
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com >
2022-02-10 09:16:50 -08:00
Jisheng Zhang and Palmer Dabbelt
7f3de1adb3
riscv: remove cpu_stop()
...
Except arch_cpu_idle_dead(), no users of this function. So remove
cpu_stop() and fold its code into arch_cpu_idle_dead().
Signed-off-by: Jisheng Zhang <jszhang@kernel.org >
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com >
2022-01-09 11:02:39 -08:00
Atish Patra and Palmer Dabbelt
f1e58583b9
RISC-V: Support cpu hotplug
...
This patch enable support for cpu hotplug in RISC-V. It uses SBI HSM
extension to online/offline any hart. As a result, the harts are
returned to firmware once they are offline. If the harts are brought
online afterwards, they re-enter Linux kernel as if a secondary hart
booted for the first time. All booting requirements are honored during
this process.
Tested both on QEMU and HighFive Unleashed board with. Test result follows.
---------------------------------------------------
Offline cpu 2
---------------------------------------------------
$ echo 0 > /sys/devices/system/cpu/cpu2/online
[ 32.828684] CPU2: off
$ cat /proc/cpuinfo
processor : 0
hart : 0
isa : rv64imafdcsu
mmu : sv48
processor : 1
hart : 1
isa : rv64imafdcsu
mmu : sv48
processor : 3
hart : 3
isa : rv64imafdcsu
mmu : sv48
processor : 4
hart : 4
isa : rv64imafdcsu
mmu : sv48
processor : 5
hart : 5
isa : rv64imafdcsu
mmu : sv48
processor : 6
hart : 6
isa : rv64imafdcsu
mmu : sv48
processor : 7
hart : 7
isa : rv64imafdcsu
mmu : sv48
---------------------------------------------------
online cpu 2
---------------------------------------------------
$ echo 1 > /sys/devices/system/cpu/cpu2/online
$ cat /proc/cpuinfo
processor : 0
hart : 0
isa : rv64imafdcsu
mmu : sv48
processor : 1
hart : 1
isa : rv64imafdcsu
mmu : sv48
processor : 2
hart : 2
isa : rv64imafdcsu
mmu : sv48
processor : 3
hart : 3
isa : rv64imafdcsu
mmu : sv48
processor : 4
hart : 4
isa : rv64imafdcsu
mmu : sv48
processor : 5
hart : 5
isa : rv64imafdcsu
mmu : sv48
processor : 6
hart : 6
isa : rv64imafdcsu
mmu : sv48
processor : 7
hart : 7
isa : rv64imafdcsu
mmu : sv48
Signed-off-by: Atish Patra <atish.patra@wdc.com >
Reviewed-by: Anup Patel <anup@brainfault.org >
2020-03-31 11:28:30 -07:00