CPU: Fall back to mmap'ed buffer if reprotecting code space fails

This commit is contained in:
Connor McLaughlin 2020-12-06 18:13:07 +10:00
parent 09495b1d93
commit f5ccb6ea60
2 changed files with 28 additions and 7 deletions

View File

@ -1,12 +1,15 @@
#include "jit_code_buffer.h"
#include "align.h"
#include "assert.h"
#include "common/log.h"
#include "cpu_detect.h"
#include <algorithm>
Log_SetChannel(JitCodeBuffer);
#if defined(WIN32)
#include "windows_headers.h"
#else
#include <errno.h>
#include <sys/mman.h>
#endif
@ -37,15 +40,22 @@ bool JitCodeBuffer::Allocate(u32 size /* = 64 * 1024 * 1024 */, u32 far_code_siz
#if defined(WIN32)
m_code_ptr = static_cast<u8*>(VirtualAlloc(nullptr, m_total_size, MEM_COMMIT, PAGE_EXECUTE_READWRITE));
if (!m_code_ptr)
{
Log_ErrorPrintf("VirtualAlloc(RWX, %u) for internal buffer failed: %u", m_total_size, GetLastError());
return false;
}
#elif defined(__linux__) || defined(__ANDROID__) || defined(__APPLE__) || defined(__HAIKU__)
m_code_ptr = static_cast<u8*>(
mmap(nullptr, m_total_size, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0));
#else
m_code_ptr = nullptr;
#endif
if (!m_code_ptr)
{
Log_ErrorPrintf("mmap(RWX, %u) for internal buffer failed: %d", m_total_size, errno);
return false;
}
#else
return false;
#endif
m_free_code_ptr = m_code_ptr;
m_code_size = size;
@ -71,7 +81,10 @@ bool JitCodeBuffer::Initialize(void* buffer, u32 size, u32 far_code_size /* = 0
#if defined(WIN32)
DWORD old_protect = 0;
if (!VirtualProtect(buffer, size, PAGE_EXECUTE_READWRITE, &old_protect))
{
Log_ErrorPrintf("VirtualProtect(RWX) for external buffer failed: %u", GetLastError());
return false;
}
if (guard_size > 0)
{
@ -80,6 +93,7 @@ bool JitCodeBuffer::Initialize(void* buffer, u32 size, u32 far_code_size /* = 0
if (!VirtualProtect(buffer, guard_size, PAGE_NOACCESS, &old_guard_protect) ||
!VirtualProtect(guard_at_end, guard_size, PAGE_NOACCESS, &old_guard_protect))
{
Log_ErrorPrintf("VirtualProtect(NOACCESS) for guard page failed: %u", GetLastError());
return false;
}
}
@ -88,14 +102,20 @@ bool JitCodeBuffer::Initialize(void* buffer, u32 size, u32 far_code_size /* = 0
m_old_protection = static_cast<u32>(old_protect);
#elif defined(__linux__) || defined(__ANDROID__) || defined(__APPLE__) || defined(__HAIKU__)
if (mprotect(buffer, size, PROT_READ | PROT_WRITE | PROT_EXEC) != 0)
{
Log_ErrorPrintf("mprotect(RWX) for external buffer failed: %d", errno);
return false;
}
if (guard_size > 0)
{
u8* guard_at_end = (static_cast<u8*>(buffer) + size) - guard_size;
if (mprotect(buffer, guard_size, PROT_NONE) != 0 || mprotect(guard_at_end, guard_size, PROT_NONE) != 0)
{
Log_ErrorPrintf("mprotect(NONE) for guard page failed: %d", errno);
return false;
}
}
// reasonable default?
m_code_ptr = static_cast<u8*>(buffer);

View File

@ -124,11 +124,12 @@ void Initialize()
if (g_settings.IsUsingRecompiler())
{
#ifdef USE_STATIC_CODE_BUFFER
if (!s_code_buffer.Initialize(s_code_storage, sizeof(s_code_storage), RECOMPILER_FAR_CODE_CACHE_SIZE,
RECOMPILER_GUARD_SIZE))
const bool has_buffer = s_code_buffer.Initialize(s_code_storage, sizeof(s_code_storage),
RECOMPILER_FAR_CODE_CACHE_SIZE, RECOMPILER_GUARD_SIZE);
#else
if (!s_code_buffer.Allocate(RECOMPILER_CODE_CACHE_SIZE, RECOMPILER_FAR_CODE_CACHE_SIZE))
const bool has_buffer = false;
#endif
if (!has_buffer && !s_code_buffer.Allocate(RECOMPILER_CODE_CACHE_SIZE, RECOMPILER_FAR_CODE_CACHE_SIZE))
{
Panic("Failed to initialize code space");
}