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author | Richard Henderson <richard.henderson@linaro.org> | 2019-08-24 09:51:09 -0700 |
---|---|---|
committer | Richard Henderson <richard.henderson@linaro.org> | 2019-09-03 08:30:39 -0700 |
commit | 50b107c5d617eaf93301cef20221312e7a986701 (patch) | |
tree | 8ff2f1b256e9847308d30c90fc431d91023e45d1 /exec.c | |
parent | 5787585d0406cfd54dda0c71ea1a603347ce6e71 (diff) | |
download | qemu-50b107c5d617eaf93301cef20221312e7a986701.zip qemu-50b107c5d617eaf93301cef20221312e7a986701.tar.gz qemu-50b107c5d617eaf93301cef20221312e7a986701.tar.bz2 |
cputlb: Handle watchpoints via TLB_WATCHPOINT
The raising of exceptions from check_watchpoint, buried inside
of the I/O subsystem, is fundamentally broken. We do not have
the helper return address with which we can unwind guest state.
Replace PHYS_SECTION_WATCH and io_mem_watch with TLB_WATCHPOINT.
Move the call to cpu_check_watchpoint into the cputlb helpers
where we do have the helper return address.
This allows watchpoints on RAM to bypass the full i/o access path.
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Diffstat (limited to 'exec.c')
-rw-r--r-- | exec.c | 114 |
1 files changed, 7 insertions, 107 deletions
@@ -193,15 +193,12 @@ typedef struct subpage_t { #define PHYS_SECTION_UNASSIGNED 0 #define PHYS_SECTION_NOTDIRTY 1 #define PHYS_SECTION_ROM 2 -#define PHYS_SECTION_WATCH 3 static void io_mem_init(void); static void memory_map_init(void); static void tcg_log_global_after_sync(MemoryListener *listener); static void tcg_commit(MemoryListener *listener); -static MemoryRegion io_mem_watch; - /** * CPUAddressSpace: all the information a CPU needs about an AddressSpace * @cpu: the CPU whose AddressSpace this is @@ -1472,7 +1469,6 @@ hwaddr memory_region_section_get_iotlb(CPUState *cpu, target_ulong *address) { hwaddr iotlb; - int flags, match; if (memory_region_is_ram(section->mr)) { /* Normal RAM. */ @@ -1490,19 +1486,6 @@ hwaddr memory_region_section_get_iotlb(CPUState *cpu, iotlb += xlat; } - /* Avoid trapping reads of pages with a write breakpoint. */ - match = (prot & PAGE_READ ? BP_MEM_READ : 0) - | (prot & PAGE_WRITE ? BP_MEM_WRITE : 0); - flags = cpu_watchpoint_address_matches(cpu, vaddr, TARGET_PAGE_SIZE); - if (flags & match) { - /* - * Make accesses to pages with watchpoints go via the - * watchpoint trap routines. - */ - iotlb = PHYS_SECTION_WATCH + paddr; - *address |= TLB_MMIO; - } - return iotlb; } #endif /* defined(CONFIG_USER_ONLY) */ @@ -2810,10 +2793,14 @@ void cpu_check_watchpoint(CPUState *cpu, vaddr addr, vaddr len, assert(tcg_enabled()); if (cpu->watchpoint_hit) { - /* We re-entered the check after replacing the TB. Now raise - * the debug interrupt so that is will trigger after the - * current instruction. */ + /* + * We re-entered the check after replacing the TB. + * Now raise the debug interrupt so that it will + * trigger after the current instruction. + */ + qemu_mutex_lock_iothread(); cpu_interrupt(cpu, CPU_INTERRUPT_DEBUG); + qemu_mutex_unlock_iothread(); return; } @@ -2858,88 +2845,6 @@ void cpu_check_watchpoint(CPUState *cpu, vaddr addr, vaddr len, } } -static void check_watchpoint(int offset, int len, MemTxAttrs attrs, int flags) -{ - CPUState *cpu = current_cpu; - vaddr addr = (cpu->mem_io_vaddr & TARGET_PAGE_MASK) + offset; - - cpu_check_watchpoint(cpu, addr, len, attrs, flags, 0); -} - -/* Watchpoint access routines. Watchpoints are inserted using TLB tricks, - so these check for a hit then pass through to the normal out-of-line - phys routines. */ -static MemTxResult watch_mem_read(void *opaque, hwaddr addr, uint64_t *pdata, - unsigned size, MemTxAttrs attrs) -{ - MemTxResult res; - uint64_t data; - int asidx = cpu_asidx_from_attrs(current_cpu, attrs); - AddressSpace *as = current_cpu->cpu_ases[asidx].as; - - check_watchpoint(addr & ~TARGET_PAGE_MASK, size, attrs, BP_MEM_READ); - switch (size) { - case 1: - data = address_space_ldub(as, addr, attrs, &res); - break; - case 2: - data = address_space_lduw(as, addr, attrs, &res); - break; - case 4: - data = address_space_ldl(as, addr, attrs, &res); - break; - case 8: - data = address_space_ldq(as, addr, attrs, &res); - break; - default: abort(); - } - *pdata = data; - return res; -} - -static MemTxResult watch_mem_write(void *opaque, hwaddr addr, - uint64_t val, unsigned size, - MemTxAttrs attrs) -{ - MemTxResult res; - int asidx = cpu_asidx_from_attrs(current_cpu, attrs); - AddressSpace *as = current_cpu->cpu_ases[asidx].as; - - check_watchpoint(addr & ~TARGET_PAGE_MASK, size, attrs, BP_MEM_WRITE); - switch (size) { - case 1: - address_space_stb(as, addr, val, attrs, &res); - break; - case 2: - address_space_stw(as, addr, val, attrs, &res); - break; - case 4: - address_space_stl(as, addr, val, attrs, &res); - break; - case 8: - address_space_stq(as, addr, val, attrs, &res); - break; - default: abort(); - } - return res; -} - -static const MemoryRegionOps watch_mem_ops = { - .read_with_attrs = watch_mem_read, - .write_with_attrs = watch_mem_write, - .endianness = DEVICE_NATIVE_ENDIAN, - .valid = { - .min_access_size = 1, - .max_access_size = 8, - .unaligned = false, - }, - .impl = { - .min_access_size = 1, - .max_access_size = 8, - .unaligned = false, - }, -}; - static MemTxResult flatview_read(FlatView *fv, hwaddr addr, MemTxAttrs attrs, uint8_t *buf, hwaddr len); static MemTxResult flatview_write(FlatView *fv, hwaddr addr, MemTxAttrs attrs, @@ -3115,9 +3020,6 @@ static void io_mem_init(void) memory_region_init_io(&io_mem_notdirty, NULL, ¬dirty_mem_ops, NULL, NULL, UINT64_MAX); memory_region_clear_global_locking(&io_mem_notdirty); - - memory_region_init_io(&io_mem_watch, NULL, &watch_mem_ops, NULL, - NULL, UINT64_MAX); } AddressSpaceDispatch *address_space_dispatch_new(FlatView *fv) @@ -3131,8 +3033,6 @@ AddressSpaceDispatch *address_space_dispatch_new(FlatView *fv) assert(n == PHYS_SECTION_NOTDIRTY); n = dummy_section(&d->map, fv, &io_mem_rom); assert(n == PHYS_SECTION_ROM); - n = dummy_section(&d->map, fv, &io_mem_watch); - assert(n == PHYS_SECTION_WATCH); d->phys_map = (PhysPageEntry) { .ptr = PHYS_MAP_NODE_NIL, .skip = 1 }; |