diff options
| author | Richard W.M. Jones <rjones@redhat.com> | 2023-10-09 13:48:25 +0100 |
|---|---|---|
| committer | Alistair Francis <alistair.francis@wdc.com> | 2023-10-12 12:40:50 +1000 |
| commit | 614c9466a238641480332b707a7a20a3593bdfb7 (patch) | |
| tree | 3bdbc58703585d510c3a23999b6081604291503f /target/riscv | |
| parent | 9b9741c38f2a92eb99c74f2bf387fc7a12d7f8e2 (diff) | |
target/riscv: Use env_archcpu for better performance
RISCV_CPU(cs) uses a checked cast. When QOM cast debugging is enabled
this adds about 5% total overhead when emulating RV64 on x86-64 host.
Using a RISC-V guest with 16 vCPUs, 16 GB of guest RAM, virtio-blk
disk. The guest has a copy of the qemu source tree. The test
involves compiling the qemu source tree with 'make clean; time make -j16'.
Before making this change the compile step took 449 & 447 seconds over
two consecutive runs.
After making this change: 428 & 421 seconds.
The saving is over 5%.
Thanks: Paolo Bonzini
Thanks: Philippe Mathieu-Daudé
Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20231009124859.3373696-2-rjones@redhat.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Diffstat (limited to 'target/riscv')
| -rw-r--r-- | target/riscv/cpu_helper.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c index 3a02079290..8c28241c18 100644 --- a/target/riscv/cpu_helper.c +++ b/target/riscv/cpu_helper.c @@ -65,8 +65,7 @@ int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch) void cpu_get_tb_cpu_state(CPURISCVState *env, vaddr *pc, uint64_t *cs_base, uint32_t *pflags) { - CPUState *cs = env_cpu(env); - RISCVCPU *cpu = RISCV_CPU(cs); + RISCVCPU *cpu = env_archcpu(env); RISCVExtStatus fs, vs; uint32_t flags = 0; |