8346237: Obsolete the UseOprofile flag

Reviewed-by: coleenp, kvn

src/hotspot/os/linux/globals_linux.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2005, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2005, 2025, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -35,9 +35,6 @@
                          range,                                         \
                          constraint)                                    \
                                                                         \
-  product(bool, UseOprofile, false,                                     \
-        "(Deprecated) enable support for Oprofile profiler")            \
-                                                                        \
   product(bool, UseTransparentHugePages, false,                         \
           "Use MADV_HUGEPAGE for large pages")                          \
                                                                         \

src/hotspot/os/linux/os_linux.cpp

@@ -2820,44 +2820,6 @@ void os::jvm_path(char *buf, jint buflen) {
 ////////////////////////////////////////////////////////////////////////////////
 // Virtual Memory
 
-// Rationale behind this function:
-//  current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
-//  mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
-//  samples for JITted code. Here we create private executable mapping over the code cache
-//  and then we can use standard (well, almost, as mapping can change) way to provide
-//  info for the reporting script by storing timestamp and location of symbol
-void linux_wrap_code(char* base, size_t size) {
-  static volatile jint cnt = 0;
-
-  static_assert(sizeof(off_t) == 8, "Expected Large File Support in this file");
-
-  if (!UseOprofile) {
-    return;
-  }
-
-  char buf[PATH_MAX+1];
-  int num = Atomic::add(&cnt, 1);
-
-  snprintf(buf, sizeof(buf), "%s/hs-vm-%d-%d",
-           os::get_temp_directory(), os::current_process_id(), num);
-  unlink(buf);
-
-  int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
-
-  if (fd != -1) {
-    off_t rv = ::lseek(fd, size-2, SEEK_SET);
-    if (rv != (off_t)-1) {
-      if (::write(fd, "", 1) == 1) {
-        mmap(base, size,
-             PROT_READ|PROT_WRITE|PROT_EXEC,
-             MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
-      }
-    }
-    ::close(fd);
-    unlink(buf);
-  }
-}
-
 static bool recoverable_mmap_error(int err) {
   // See if the error is one we can let the caller handle. This
   // list of errno values comes from JBS-6843484. I can't find a

src/hotspot/share/memory/heap.cpp

@@ -189,14 +189,6 @@ static size_t align_to_page_size(size_t size) {
 }
 
 
-void CodeHeap::on_code_mapping(char* base, size_t size) {
-#ifdef LINUX
-  extern void linux_wrap_code(char* base, size_t size);
-  linux_wrap_code(base, size);
-#endif
-}
-
-
 bool CodeHeap::reserve(ReservedSpace rs, size_t committed_size, size_t segment_size) {
   assert(rs.size() >= committed_size, "reserved < committed");
   assert(is_aligned(committed_size, rs.page_size()), "must be page aligned");
@@ -213,7 +205,6 @@ bool CodeHeap::reserve(ReservedSpace rs, size_t committed_size, size_t segment_s
     return false;
   }
 
-  on_code_mapping(_memory.low(), _memory.committed_size());
   _number_of_committed_segments = size_to_segments(_memory.committed_size());
   _number_of_reserved_segments  = size_to_segments(_memory.reserved_size());
   assert(_number_of_reserved_segments >= _number_of_committed_segments, "just checking");
@@ -250,7 +241,6 @@ bool CodeHeap::expand_by(size_t size) {
     }
     char* base = _memory.low() + _memory.committed_size();
     if (!_memory.expand_by(dm)) return false;
-    on_code_mapping(base, dm);
     size_t i = _number_of_committed_segments;
     _number_of_committed_segments = size_to_segments(_memory.committed_size());
     assert(_number_of_reserved_segments == size_to_segments(_memory.reserved_size()), "number of reserved segments should not change");

src/hotspot/share/memory/heap.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -146,9 +146,6 @@ class CodeHeap : public CHeapObj<mtCode> {
   void*      next_used(HeapBlock* b) const;
   HeapBlock* block_start(void* p) const;
 
-  // to perform additional actions on creation of executable code
-  void on_code_mapping(char* base, size_t size);
-
  public:
   CodeHeap(const char* name, const CodeBlobType code_blob_type);
 

src/hotspot/share/runtime/arguments.cpp

@@ -530,7 +530,6 @@ static SpecialFlag const special_jvm_flags[] = {
   { "UseSharedSpaces",              JDK_Version::jdk(18), JDK_Version::jdk(19), JDK_Version::undefined() },
 #ifdef LINUX
   { "UseLinuxPosixThreadCPUClocks", JDK_Version::jdk(24), JDK_Version::jdk(25), JDK_Version::jdk(26) },
-  { "UseOprofile",                  JDK_Version::jdk(25), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 #endif
   { "LockingMode",                  JDK_Version::jdk(24), JDK_Version::jdk(26), JDK_Version::jdk(27) },
 #ifdef _LP64
@@ -542,6 +541,9 @@ static SpecialFlag const special_jvm_flags[] = {
   // -------------- Obsolete Flags - sorted by expired_in --------------
 
   { "PerfDataSamplingInterval",     JDK_Version::undefined(), JDK_Version::jdk(25), JDK_Version::jdk(26) },
+#ifdef LINUX
+  { "UseOprofile",                  JDK_Version::jdk(25), JDK_Version::jdk(26), JDK_Version::jdk(27) },
+#endif
   { "MetaspaceReclaimPolicy",       JDK_Version::undefined(), JDK_Version::jdk(21), JDK_Version::undefined() },
   { "ZGenerational",                JDK_Version::jdk(23), JDK_Version::jdk(24), JDK_Version::undefined() },
   { "ZMarkStackSpaceLimit",         JDK_Version::undefined(), JDK_Version::jdk(25), JDK_Version::undefined() },