diff options
| author | Jisheng Zhang <jszhang@kernel.org> | 2023-09-12 23:40:40 +0800 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2023-11-05 09:05:51 -0800 |
| commit | c20d36cc2a2073d4cdcda92bd7a1bb9b3b3b7c79 (patch) | |
| tree | 27fdb74d2935c6f6d6f1166be5af4d9ecc1924e6 /arch | |
| parent | 07863871dfb162965b21bb8c2e4861bdb0019da3 (diff) | |
| download | linux-stable-c20d36cc2a2073d4cdcda92bd7a1bb9b3b3b7c79.tar.gz linux-stable-c20d36cc2a2073d4cdcda92bd7a1bb9b3b3b7c79.tar.bz2 linux-stable-c20d36cc2a2073d4cdcda92bd7a1bb9b3b3b7c79.zip | |
riscv: don't probe unaligned access speed if already done
If misaligned_access_speed percpu var isn't so called "HWPROBE
MISALIGNED UNKNOWN", it means the probe has happened(this is possible
for example, hotplug off then hotplug on one cpu), and the percpu var
has been set, don't probe again in this case.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Fixes: 584ea6564bca ("RISC-V: Probe for unaligned access speed")
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230912154040.3306-1-jszhang@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/riscv/kernel/cpufeature.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c index 970a71422bee..6a01ded615cd 100644 --- a/arch/riscv/kernel/cpufeature.c +++ b/arch/riscv/kernel/cpufeature.c @@ -572,6 +572,10 @@ void check_unaligned_access(int cpu) if (check_unaligned_access_emulated(cpu)) return; + /* We are already set since the last check */ + if (per_cpu(misaligned_access_speed, cpu) != RISCV_HWPROBE_MISALIGNED_UNKNOWN) + return; + page = alloc_pages(GFP_NOWAIT, get_order(MISALIGNED_BUFFER_SIZE)); if (!page) { pr_warn("Can't alloc pages to measure memcpy performance"); |