Files
FEX-Emu--FEX/External/FEXCore/Source/Common/JitSymbols.cpp
T
Ryan Houdek 6193bddaa5 JitSymbols: Fixes file opening and writing
We shouldn't use O_EXCL, since we need to overwrite previous entry PIDs
if they happen to exist. The kernel ensures that PIDs don't overlap, but
in some kernel configurations PIDs are aggressively reused, resulting
in O_EXCL quickly hitting an issue when writing stale files.

Additionally O_DIRECT, this doesn't allow us to write to files, so all
write functions were failing.

Additionally use O_APPEND, we are only ever appending, so let the kernel
know.

Additionally use O_TRUNC, in the case that a stale perf file exists,
this will immediately truncate the file to zero.
2023-01-19 01:13:44 -08:00

87 lines
2.6 KiB
C++

#include "Common/JitSymbols.h"
#include <fcntl.h>
#include <string>
#include <unistd.h>
#include <fmt/format.h>
namespace FEXCore {
JITSymbols::JITSymbols() {
}
JITSymbols::~JITSymbols() {
if (fd != -1) {
close(fd);
}
}
void JITSymbols::InitFile() {
// We can't use FILE here since we must be robust against forking processes closing our FD from under us.
const auto PerfMap = fmt::format("/tmp/perf-{}.map", getpid());
fd = open(PerfMap.c_str(), O_CREAT | O_TRUNC | O_WRONLY | O_APPEND, 0644);
}
void JITSymbols::Register(const void *HostAddr, uint64_t GuestAddr, uint32_t CodeSize) {
if (fd == -1) return;
// Linux perf format is very straightforward
// `<HostPtr> <Size> <Name>\n`
const auto Buffer = fmt::format("{} {:x} JIT_0x{:x}_{}\n", HostAddr, CodeSize, GuestAddr, HostAddr);
auto Result = write(fd, Buffer.c_str(), Buffer.size());
if (Result == -1 && errno == EBADF) {
fd = -1;
}
}
void JITSymbols::Register(const void *HostAddr, uint32_t CodeSize, std::string_view Name) {
if (fd == -1) return;
// Linux perf format is very straightforward
// `<HostPtr> <Size> <Name>\n`
const auto Buffer = fmt::format("{} {:x} {}_{}\n", HostAddr, CodeSize, Name, HostAddr);
auto Result = write(fd, Buffer.c_str(), Buffer.size());
if (Result == -1 && errno == EBADF) {
fd = -1;
}
}
void JITSymbols::Register(const void *HostAddr, uint32_t CodeSize, std::string_view Name, uintptr_t Offset) {
if (fd == -1) return;
// Linux perf format is very straightforward
// `<HostPtr> <Size> <Name>\n`
const auto Buffer = fmt::format("{} {:x} {}+0x{:x} ({})\n", HostAddr, CodeSize, Name, Offset, HostAddr);
auto Result = write(fd, Buffer.c_str(), Buffer.size());
if (Result == -1 && errno == EBADF) {
fd = -1;
}
}
void JITSymbols::RegisterNamedRegion(const void *HostAddr, uint32_t CodeSize, std::string_view Name) {
if (fd == -1) return;
// Linux perf format is very straightforward
// `<HostPtr> <Size> <Name>\n`
const auto Buffer = fmt::format("{} {:x} {}\n", HostAddr, CodeSize, Name);
auto Result = write(fd, Buffer.c_str(), Buffer.size());
if (Result == -1 && errno == EBADF) {
fd = -1;
}
}
void JITSymbols::RegisterJITSpace(const void *HostAddr, uint32_t CodeSize) {
if (fd == -1) return;
// Linux perf format is very straightforward
// `<HostPtr> <Size> <Name>\n`
const auto Buffer = fmt::format("{} {:x} FEXJIT\n", HostAddr, CodeSize);
auto Result = write(fd, Buffer.c_str(), Buffer.size());
if (Result == -1 && errno == EBADF) {
fd = -1;
}
}
} // namespace FEXCore