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target/riscv: Simplify probing in vext_ldff

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The current pairing of tlb_vaddr_to_host with extra is either
inefficient (user-only, with page_check_range) or incorrect
(system, with probe_pages).

For proper non-fault behaviour, use probe_access_flags with
its nonfault parameter set to true.

Reviewed-by: Max Chou <max.chou@sifive.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2024-07-09 20:10:55 -07:00
parent 2730df9190
commit 3f57638a7e
1 changed files with 17 additions and 14 deletions
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31
target/riscv/vector_helper.c
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@ -474,7 +474,6 @@ vext_ldff(void *vd, void *v0, target_ulong base,
vext_ldst_elem_fn *ldst_elem,
uint32_t log2_esz, uintptr_t ra)
{
void *host;
uint32_t i, k, vl = 0;
uint32_t nf = vext_nf(desc);
uint32_t vm = vext_vm(desc);
@ -493,27 +492,31 @@ vext_ldff(void *vd, void *v0, target_ulong base,
}
addr = adjust_addr(env, base + i * (nf << log2_esz));
if (i == 0) {
/* Allow fault on first element. */
probe_pages(env, addr, nf << log2_esz, ra, MMU_DATA_LOAD);
} else {
/* if it triggers an exception, no need to check watchpoint */
remain = nf << log2_esz;
while (remain > 0) {
void *host;
int flags;
offset = -(addr | TARGET_PAGE_MASK);
host = tlb_vaddr_to_host(env, addr, MMU_DATA_LOAD, mmu_index);
if (host) {
#ifdef CONFIG_USER_ONLY
if (!page_check_range(addr, offset, PAGE_READ)) {
vl = i;
goto ProbeSuccess;
}
#else
probe_pages(env, addr, offset, ra, MMU_DATA_LOAD);
#endif
} else {
/* Probe nonfault on subsequent elements. */
flags = probe_access_flags(env, addr, offset, MMU_DATA_LOAD,
mmu_index, true, &host, 0);
/*
* Stop if invalid (unmapped) or mmio (transaction may fail).
* Do not stop if watchpoint, as the spec says that
* first-fault should continue to access the same
* elements regardless of any watchpoint.
*/
if (flags & ~TLB_WATCHPOINT) {
vl = i;
goto ProbeSuccess;
}
if (remain <= offset) {
if (remain <= offset) {
break;
}
remain -= offset;