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Revise PAL API
Add error handling
Clean up #ifdef CROSSGEN
Add COMPlus_PerfMapJitDumpPath
Add placeholder debuginfo and unwindinfo arguments

Documentation/project-docs/clr-configuration-knobs.md

@@ -709,6 +709,7 @@ Name | Description | Type | Class | Default Value | Flags
 `ETWEnabled` | This flag is used on OSes < Vista to enable/disable ETW. It is disabled by default | `DWORD` | `EXTERNAL` | `0` | REGUTIL_default
 `MsBetweenAttachCheck` | | `DWORD` | `EXTERNAL` | `500` |
 `PerfMapEnabled` | This flag is used on Linux to enable writing /tmp/perf-$pid.map. It is disabled by default | `DWORD` | `EXTERNAL` | `0` | REGUTIL_default
+`PerfMapJitDumpPath` | Specifies a path to write the perf jitdump file. Defaults to GetTempPathA() | `STRING` | `EXTERNAL` | | REGUTIL_default
 `PerfMapIgnoreSignal` | When perf map is enabled, this option will configure the specified signal to be accepted and ignored as a marker in the perf logs. It is disabled by default | `DWORD` | `EXTERNAL` | `0` | REGUTIL_default
 `ProfAPI_AttachProfilerMinTimeoutInMs` | Timeout in ms for the minimum time out value of AttachProfiler | `DWORD` | `EXTERNAL` | `10*1000` |
 `ProfAPI_DetachMaxSleepMs` | The maximum time, in milliseconds, the CLR will wait before checking whether a profiler that is in the process of detaching is ready to be unloaded. | `DWORD` | `EXTERNAL` | `0` |

src/inc/clrconfigvalues.h

@@ -562,6 +562,7 @@ RETAIL_CONFIG_DWORD_INFO(UNSUPPORTED_ProfAPI_ValidateNGENInstrumentation, W("Pro
 
 #ifdef FEATURE_PERFMAP
 RETAIL_CONFIG_DWORD_INFO_EX(EXTERNAL_PerfMapEnabled, W("PerfMapEnabled"), 0, "This flag is used on Linux to enable writing /tmp/perf-$pid.map. It is disabled by default", CLRConfig::REGUTIL_default)
+CONFIG_STRING_INFO_EX(EXTERNAL_PerfMapJitDumpPath, W("PerfMapJitDumpPath"), "Specifies a path to write the perf jitdump file. Defaults to GetTempPathA()", CLRConfig::REGUTIL_default)
 RETAIL_CONFIG_DWORD_INFO_EX(EXTERNAL_PerfMapIgnoreSignal, W("PerfMapIgnoreSignal"), 0, "When perf map is enabled, this option will configure the specified signal to be accepted and ignored as a marker in the perf logs. It is disabled by default", CLRConfig::REGUTIL_default)
 RETAIL_CONFIG_DWORD_INFO(EXTERNAL_PerfMapShowOptimizationTiers, W("PerfMapShowOptimizationTiers"), 1, "Shows optimization tiers in the perf map for methods, as part of the symbol name. Useful for seeing separate stack frames for different optimization tiers of each method.")
 RETAIL_CONFIG_STRING_INFO(EXTERNAL_NativeImagePerfMapFormat, W("NativeImagePerfMapFormat"), "Specifies the format of native image perfmap files generated by crossgen. Valid options are RVA or OFFSET.")

src/inc/perfjitdump.h

@@ -6,24 +6,20 @@
 #ifndef PERF_JITDUMP_H
 #define PERF_JITDUMP_H
 
-struct PerfJitDumpState;
-
-// Generates a perf jitdump file.
-class PerfJitDump
-{
-private:
- static PerfJitDumpState& GetState();
-
-public:
- // Start the jitdump file
- static void Start();
-
- // Log a method to the jitdump file.
- static void LogMethod(void* pCode, size_t codeSize, const char* symbol);
-
- // Finish the jitdump file
- static void Finish();
-};
+int
+PALAPI
+// Start the jitdump file
+PAL_PerfJitDump_Start(const char* path);
+
+int
+PALAPI
+// Log a method to the jitdump file.
+PAL_PerfJitDump_LogMethod(void* pCode, size_t codeSize, const char* symbol, void* debugInfo, void* unwindInfo);
+
+int
+PALAPI
+// Finish the jitdump file
+PAL_PerfJitDump_Finish();
 
 #endif // PERF_JITDUMP_H
 

src/pal/src/misc/perfjitdump.cpp

@@ -3,7 +3,7 @@
 // See the LICENSE file in the project root for more information.
 // ===========================================================================
 
-#if defined(__linux__)
+#if defined(__linux__) && !defined(CROSSGEN_COMPILE)
 #define JITDUMP_SUPPORTED
 #endif
 
@@ -26,6 +26,7 @@
 #include <sys/syscall.h>
 #include <time.h>
 #include <unistd.h>
+#include <linux/limits.h>
 
 #include "../inc/llvm/ELF.h"
 
@@ -141,38 +142,66 @@ struct PerfJitDumpState
  pthread_mutex_t mutex;
  uint64_t codeIndex;
 
- void Start()
+ int Start(const char* path)
  {
- pthread_mutex_lock(&mutex);
+ int result = 0;
 
- char jitdumpPath[1024];
+ // Write file header
+ FileHeader header;
 
- snprintf(jitdumpPath, sizeof(jitdumpPath), "/tmp/jit-%i.dump", getpid());
+ result = pthread_mutex_lock(&mutex);
 
- fd = open(jitdumpPath, O_CREAT|O_TRUNC|O_RDWR|O_CLOEXEC, S_IRUSR|S_IWUSR );
+ if (enabled)
+ goto exit;
 
- // Write file header
- FileHeader header;
+ if (result != 0)
+ goto exit;
+
+ char jitdumpPath[PATH_MAX];
+
+ result = snprintf(jitdumpPath, sizeof(jitdumpPath), "%s/jit-%i.dump", path, getpid());
+
+ if (result >= PATH_MAX)
+ goto exit;
+
+ result = open(jitdumpPath, O_CREAT|O_TRUNC|O_RDWR|O_CLOEXEC, S_IRUSR|S_IWUSR );
+
+ if (result == -1)
+ goto exit;
+
+ fd = result;
 
- write(fd, &header, sizeof(FileHeader));
+ result = write(fd, &header, sizeof(FileHeader));
 
- fsync(fd);
+ if (result == -1)
+ goto exit;
+
+ result = fsync(fd);
+
+ if (result == -1)
+ goto exit;
 
  // mmap jitdump file
  // this is a marker for perf inject to find the jitdumpfile
  mmapAddr = mmap(nullptr, sizeof(FileHeader), PROT_READ | PROT_EXEC, MAP_PRIVATE, fd, 0);
 
+ if (mmapAddr == MAP_FAILED)
+ goto exit;
+
  enabled = true;
 
- pthread_mutex_unlock(&mutex);
+exit:
+ result = pthread_mutex_unlock(&mutex);
+
+ return result;
  }
 
- void LogMethod(void* pCode, size_t codeSize, const char* symbol)
+ int LogMethod(void* pCode, size_t codeSize, const char* symbol, void* debugInfo, void* unwindInfo)
  {
+ int result = 0;
+
  if (enabled)
  {
- pthread_mutex_lock(&mutex);
-
  size_t symbolLen = strlen(symbol);
 
  JitCodeLoadRecord record;
@@ -182,86 +211,134 @@ struct PerfJitDumpState
  record.code_size = codeSize;
  record.code_index = ++codeIndex;
  record.header.total_size = sizeof(JitCodeLoadRecord) + symbolLen + 1 + codeSize;
+
+ result = pthread_mutex_lock(&mutex);
+
+ if (result != 0)
+ goto exit;
+
+ if (!enabled)
+ goto exit;
+
+ // ToDo write debugInfo and unwindInfo immediately before the JitCodeLoadRecord (while lock is held).
+
  record.header.timestamp = GetTimeStampNS();
 
- write(fd, &record, sizeof(JitCodeLoadRecord));
+ result = write(fd, &record, sizeof(JitCodeLoadRecord));
 
- write(fd, symbol, symbolLen + 1);
+ if (result == -1)
+ goto exit;
 
- write(fd, pCode, codeSize);
+ result = write(fd, symbol, symbolLen + 1);
 
- fsync(fd);
+ if (result == -1)
+ goto exit;
 
- pthread_mutex_unlock(&mutex);
+ result = write(fd, pCode, codeSize);
+
+ if (result == -1)
+ goto exit;
+
+ result = fsync(fd);
+
+ if (result == -1)
+ goto exit;
+
+exit:
+ if (result != 0)
+ enabled = false;
+
+ result = pthread_mutex_unlock(&mutex);
  }
+ return result;
  }
 
- void Finish()
+ int Finish()
  {
+ int result = 0;
+
  if (enabled)
  {
+ enabled = false;
+
  // Lock the mutex
- pthread_mutex_lock(&mutex);
+ result = pthread_mutex_lock(&mutex);
 
- enabled = false;
+ if (result != 0)
+ goto exit;
+
+ result = munmap(mmapAddr, sizeof(FileHeader));
+
+ if (result == -1)
+ goto exit;
 
- munmap(mmapAddr, sizeof(FileHeader));
+ result = fsync(fd);
 
- fsync(fd);
+ if (result == -1)
+ goto exit;
 
- close(fd);
+ result = close(fd);
 
- pthread_mutex_unlock(&mutex);
+ if (result == -1)
+ goto exit;
+
+exit:
+ result = pthread_mutex_unlock(&mutex);
  }
+ return result;
  }
 };
 
 
-PerfJitDumpState& PerfJitDump::GetState()
+PerfJitDumpState& GetState()
 {
  static PerfJitDumpState s;
 
  return s;
 }
 
-void PerfJitDump::Start()
+int
+PALAPI
+PAL_PerfJitDump_Start(const char* path)
 {
- GetState().Start();
+ return GetState().Start(path);
 }
 
-void PerfJitDump::LogMethod(void* pCode, size_t codeSize, const char* symbol)
+int
+PALAPI
+PAL_PerfJitDump_LogMethod(void* pCode, size_t codeSize, const char* symbol, void* debugInfo, void* unwindInfo)
 {
- GetState().LogMethod(pCode, codeSize, symbol);
+ return GetState().LogMethod(pCode, codeSize, symbol, debugInfo, unwindInfo);
 }
 
-void PerfJitDump::Finish()
+int
+PALAPI
+PAL_PerfJitDump_Finish()
 {
- GetState().Finish();
+ return GetState().Finish();
 }
 
 #else // JITDUMP_SUPPORTED
 
-struct PerfJitDumpState
-{
-};
-
-PerfJitDumpState& PerfJitDump::GetState()
-{
- static PerfJitDumpState s;
-
- return s;
-}
-
-void PerfJitDump::Start()
+int
+PALAPI
+PAL_PerfJitDump_Start(const char* path)
 {
+ return 0;
 }
 
-void PerfJitDump::LogMethod(void* pCode, size_t codeSize, const char* symbol)
+int
+PALAPI
+PAL_PerfJitDump_LogMethod(void* pCode, size_t codeSize, const char* symbol, void* debugInfo, void* unwindInfo)
 {
+ return 0;
 }
 
-void PerfJitDump::Finish()
+int
+PALAPI
+PAL_PerfJitDump_Finish()
 {
+ return 0;
 }
 
 #endif // JITDUMP_SUPPORTED