diff options
| author | Richard Henderson <richard.henderson@linaro.org> | 2024-07-09 16:56:48 -0700 |
|---|---|---|
| committer | Richard Henderson <richard.henderson@linaro.org> | 2024-07-23 10:56:16 +1000 |
| commit | f6bcc5b8f91e3c1b855c3078d9133f3918080276 (patch) | |
| tree | 0d01d6a4ca533b476d0b11ab3771d6c752d18acb | |
| parent | c6d84fd7cfb46a67c5c0404e93ed024cd3a14e6e (diff) | |
target/ppc: Improve helper_dcbz for user-only
Mark the reserve_addr check unlikely. Use tlb_vaddr_to_host
instead of probe_write, relying on the memset itself to test
for page writability. Use set/clear_helper_retaddr so that
we can properly unwind on segfault.
With this, a trivial loop around guest memset will no longer
spend nearly 25% of runtime within page_get_flags.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
| -rw-r--r-- | target/ppc/mem_helper.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/target/ppc/mem_helper.c b/target/ppc/mem_helper.c index 24bae3b80c..953dd08d5d 100644 --- a/target/ppc/mem_helper.c +++ b/target/ppc/mem_helper.c @@ -280,20 +280,27 @@ static void dcbz_common(CPUPPCState *env, target_ulong addr, addr &= mask; /* Check reservation */ - if ((env->reserve_addr & mask) == addr) { + if (unlikely((env->reserve_addr & mask) == addr)) { env->reserve_addr = (target_ulong)-1ULL; } /* Try fast path translate */ +#ifdef CONFIG_USER_ONLY + haddr = tlb_vaddr_to_host(env, addr, MMU_DATA_STORE, mmu_idx); +#else haddr = probe_write(env, addr, dcbz_size, mmu_idx, retaddr); - if (haddr) { - memset(haddr, 0, dcbz_size); - } else { + if (unlikely(!haddr)) { /* Slow path */ for (int i = 0; i < dcbz_size; i += 8) { cpu_stq_mmuidx_ra(env, addr + i, 0, mmu_idx, retaddr); } + return; } +#endif + + set_helper_retaddr(retaddr); + memset(haddr, 0, dcbz_size); + clear_helper_retaddr(); } void helper_dcbz(CPUPPCState *env, target_ulong addr, int mmu_idx) |