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tcg: Define and use new tlb_hit() and tlb_hit_page() functions
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The condition to check whether an address has hit against a particular
TLB entry is not completely trivial. We do this in various places, and
in fact in one place (get_page_addr_code()) we have got the condition
wrong. Abstract it out into new tlb_hit() and tlb_hit_page() inline
functions (one for a known-page-aligned address and one for an
arbitrary address), and use them in all the places where we had the
condition correct.

This is a no-behaviour-change patch; we leave fixing the buggy
code in get_page_addr_code() to a subsequent patch.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20180629162122.19376-2-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
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pm215 authored and rth7680 committed Jul 2, 2018
1 parent a688e73 commit 334692b
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Showing 4 changed files with 35 additions and 22 deletions.
15 changes: 5 additions & 10 deletions accel/tcg/cputlb.c
Expand Up @@ -239,12 +239,9 @@ void tlb_flush_by_mmuidx_all_cpus_synced(CPUState *src_cpu,

static inline void tlb_flush_entry(CPUTLBEntry *tlb_entry, target_ulong addr)
{
if (addr == (tlb_entry->addr_read &
(TARGET_PAGE_MASK | TLB_INVALID_MASK)) ||
addr == (tlb_entry->addr_write &
(TARGET_PAGE_MASK | TLB_INVALID_MASK)) ||
addr == (tlb_entry->addr_code &
(TARGET_PAGE_MASK | TLB_INVALID_MASK))) {
if (tlb_hit_page(tlb_entry->addr_read, addr) ||
tlb_hit_page(tlb_entry->addr_write, addr) ||
tlb_hit_page(tlb_entry->addr_code, addr)) {
memset(tlb_entry, -1, sizeof(*tlb_entry));
}
}
Expand Down Expand Up @@ -1046,8 +1043,7 @@ void probe_write(CPUArchState *env, target_ulong addr, int size, int mmu_idx,
int index = (addr >> TARGET_PAGE_BITS) & (CPU_TLB_SIZE - 1);
target_ulong tlb_addr = env->tlb_table[mmu_idx][index].addr_write;

if ((addr & TARGET_PAGE_MASK)
!= (tlb_addr & (TARGET_PAGE_MASK | TLB_INVALID_MASK))) {
if (!tlb_hit(tlb_addr, addr)) {
/* TLB entry is for a different page */
if (!VICTIM_TLB_HIT(addr_write, addr)) {
tlb_fill(ENV_GET_CPU(env), addr, size, MMU_DATA_STORE,
Expand Down Expand Up @@ -1091,8 +1087,7 @@ static void *atomic_mmu_lookup(CPUArchState *env, target_ulong addr,
}

/* Check TLB entry and enforce page permissions. */
if ((addr & TARGET_PAGE_MASK)
!= (tlb_addr & (TARGET_PAGE_MASK | TLB_INVALID_MASK))) {
if (!tlb_hit(tlb_addr, addr)) {
if (!VICTIM_TLB_HIT(addr_write, addr)) {
tlb_fill(ENV_GET_CPU(env), addr, 1 << s_bits, MMU_DATA_STORE,
mmu_idx, retaddr);
Expand Down
16 changes: 6 additions & 10 deletions accel/tcg/softmmu_template.h
Expand Up @@ -123,8 +123,7 @@ WORD_TYPE helper_le_ld_name(CPUArchState *env, target_ulong addr,
}

/* If the TLB entry is for a different page, reload and try again. */
if ((addr & TARGET_PAGE_MASK)
!= (tlb_addr & (TARGET_PAGE_MASK | TLB_INVALID_MASK))) {
if (!tlb_hit(tlb_addr, addr)) {
if (!VICTIM_TLB_HIT(ADDR_READ, addr)) {
tlb_fill(ENV_GET_CPU(env), addr, DATA_SIZE, READ_ACCESS_TYPE,
mmu_idx, retaddr);
Expand Down Expand Up @@ -191,8 +190,7 @@ WORD_TYPE helper_be_ld_name(CPUArchState *env, target_ulong addr,
}

/* If the TLB entry is for a different page, reload and try again. */
if ((addr & TARGET_PAGE_MASK)
!= (tlb_addr & (TARGET_PAGE_MASK | TLB_INVALID_MASK))) {
if (!tlb_hit(tlb_addr, addr)) {
if (!VICTIM_TLB_HIT(ADDR_READ, addr)) {
tlb_fill(ENV_GET_CPU(env), addr, DATA_SIZE, READ_ACCESS_TYPE,
mmu_idx, retaddr);
Expand Down Expand Up @@ -286,8 +284,7 @@ void helper_le_st_name(CPUArchState *env, target_ulong addr, DATA_TYPE val,
}

/* If the TLB entry is for a different page, reload and try again. */
if ((addr & TARGET_PAGE_MASK)
!= (tlb_addr & (TARGET_PAGE_MASK | TLB_INVALID_MASK))) {
if (!tlb_hit(tlb_addr, addr)) {
if (!VICTIM_TLB_HIT(addr_write, addr)) {
tlb_fill(ENV_GET_CPU(env), addr, DATA_SIZE, MMU_DATA_STORE,
mmu_idx, retaddr);
Expand Down Expand Up @@ -322,7 +319,7 @@ void helper_le_st_name(CPUArchState *env, target_ulong addr, DATA_TYPE val,
page2 = (addr + DATA_SIZE) & TARGET_PAGE_MASK;
index2 = (page2 >> TARGET_PAGE_BITS) & (CPU_TLB_SIZE - 1);
tlb_addr2 = env->tlb_table[mmu_idx][index2].addr_write;
if (page2 != (tlb_addr2 & (TARGET_PAGE_MASK | TLB_INVALID_MASK))
if (!tlb_hit_page(tlb_addr2, page2)
&& !VICTIM_TLB_HIT(addr_write, page2)) {
tlb_fill(ENV_GET_CPU(env), page2, DATA_SIZE, MMU_DATA_STORE,
mmu_idx, retaddr);
Expand Down Expand Up @@ -364,8 +361,7 @@ void helper_be_st_name(CPUArchState *env, target_ulong addr, DATA_TYPE val,
}

/* If the TLB entry is for a different page, reload and try again. */
if ((addr & TARGET_PAGE_MASK)
!= (tlb_addr & (TARGET_PAGE_MASK | TLB_INVALID_MASK))) {
if (!tlb_hit(tlb_addr, addr)) {
if (!VICTIM_TLB_HIT(addr_write, addr)) {
tlb_fill(ENV_GET_CPU(env), addr, DATA_SIZE, MMU_DATA_STORE,
mmu_idx, retaddr);
Expand Down Expand Up @@ -400,7 +396,7 @@ void helper_be_st_name(CPUArchState *env, target_ulong addr, DATA_TYPE val,
page2 = (addr + DATA_SIZE) & TARGET_PAGE_MASK;
index2 = (page2 >> TARGET_PAGE_BITS) & (CPU_TLB_SIZE - 1);
tlb_addr2 = env->tlb_table[mmu_idx][index2].addr_write;
if (page2 != (tlb_addr2 & (TARGET_PAGE_MASK | TLB_INVALID_MASK))
if (!tlb_hit_page(tlb_addr2, page2)
&& !VICTIM_TLB_HIT(addr_write, page2)) {
tlb_fill(ENV_GET_CPU(env), page2, DATA_SIZE, MMU_DATA_STORE,
mmu_idx, retaddr);
Expand Down
23 changes: 23 additions & 0 deletions include/exec/cpu-all.h
Expand Up @@ -339,6 +339,29 @@ CPUArchState *cpu_copy(CPUArchState *env);
#define TLB_FLAGS_MASK (TLB_INVALID_MASK | TLB_NOTDIRTY | TLB_MMIO \
| TLB_RECHECK)

/**
* tlb_hit_page: return true if page aligned @addr is a hit against the
* TLB entry @tlb_addr
*
* @addr: virtual address to test (must be page aligned)
* @tlb_addr: TLB entry address (a CPUTLBEntry addr_read/write/code value)
*/
static inline bool tlb_hit_page(target_ulong tlb_addr, target_ulong addr)
{
return addr == (tlb_addr & (TARGET_PAGE_MASK | TLB_INVALID_MASK));
}

/**
* tlb_hit: return true if @addr is a hit against the TLB entry @tlb_addr
*
* @addr: virtual address to test (need not be page aligned)
* @tlb_addr: TLB entry address (a CPUTLBEntry addr_read/write/code value)
*/
static inline bool tlb_hit(target_ulong tlb_addr, target_ulong addr)
{
return tlb_hit_page(tlb_addr, addr & TARGET_PAGE_MASK);
}

void dump_exec_info(FILE *f, fprintf_function cpu_fprintf);
void dump_opcount_info(FILE *f, fprintf_function cpu_fprintf);
#endif /* !CONFIG_USER_ONLY */
Expand Down
3 changes: 1 addition & 2 deletions include/exec/cpu_ldst.h
Expand Up @@ -422,8 +422,7 @@ static inline void *tlb_vaddr_to_host(CPUArchState *env, target_ulong addr,
g_assert_not_reached();
}

if ((addr & TARGET_PAGE_MASK)
!= (tlb_addr & (TARGET_PAGE_MASK | TLB_INVALID_MASK))) {
if (!tlb_hit(tlb_addr, addr)) {
/* TLB entry is for a different page */
return NULL;
}
Expand Down

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