Backport ec9bee6

Author: rnkovacs

src/hotspot/cpu/aarch64/vm_version_aarch64.cpp

@@ -24,100 +24,35 @@
  */
 
 #include "precompiled.hpp"
-#include "asm/macroAssembler.hpp"
-#include "asm/macroAssembler.inline.hpp"
-#include "memory/resourceArea.hpp"
+#include "runtime/arguments.hpp"
+#include "runtime/globals_extension.hpp"
 #include "runtime/java.hpp"
-#include "runtime/stubCodeGenerator.hpp"
+#include "runtime/os.hpp"
 #include "runtime/vm_version.hpp"
+#include "utilities/formatBuffer.hpp"
 #include "utilities/macros.hpp"
 
 #include OS_HEADER_INLINE(os)
 
-#include <sys/auxv.h>
-#include <asm/hwcap.h>
-
-#ifndef HWCAP_AES
-#define HWCAP_AES   (1<<3)
-#endif
-
-#ifndef HWCAP_PMULL
-#define HWCAP_PMULL (1<<4)
-#endif
-
-#ifndef HWCAP_SHA1
-#define HWCAP_SHA1  (1<<5)
-#endif
-
-#ifndef HWCAP_SHA2
-#define HWCAP_SHA2  (1<<6)
-#endif
-
-#ifndef HWCAP_CRC32
-#define HWCAP_CRC32 (1<<7)
-#endif
-
-#ifndef HWCAP_ATOMICS
-#define HWCAP_ATOMICS (1<<8)
-#endif
-
 int VM_Version::_cpu;
 int VM_Version::_model;
 int VM_Version::_model2;
 int VM_Version::_variant;
 int VM_Version::_revision;
 int VM_Version::_stepping;
-VM_Version::PsrInfo VM_Version::_psr_info   = { 0, };
-
-static BufferBlob* stub_blob;
-static const int stub_size = 550;
-
-extern "C" {
-  typedef void (*getPsrInfo_stub_t)(void*);
-}
-static getPsrInfo_stub_t getPsrInfo_stub = NULL;
-
-
-class VM_Version_StubGenerator: public StubCodeGenerator {
- public:
-
-  VM_Version_StubGenerator(CodeBuffer *c) : StubCodeGenerator(c) {}
-
-  address generate_getPsrInfo() {
-    StubCodeMark mark(this, "VM_Version", "getPsrInfo_stub");
-#   define __ _masm->
-    address start = __ pc();
-
-    // void getPsrInfo(VM_Version::PsrInfo* psr_info);
-
-    address entry = __ pc();
 
-    __ enter();
+int VM_Version::_zva_length;
+int VM_Version::_dcache_line_size;
+int VM_Version::_icache_line_size;
 
-    __ get_dczid_el0(rscratch1);
-    __ strw(rscratch1, Address(c_rarg0, in_bytes(VM_Version::dczid_el0_offset())));
-
-    __ get_ctr_el0(rscratch1);
-    __ strw(rscratch1, Address(c_rarg0, in_bytes(VM_Version::ctr_el0_offset())));
-
-    __ leave();
-    __ ret(lr);
-
-#   undef __
-
-    return start;
-  }
-};
-
-
-void VM_Version::get_processor_features() {
+void VM_Version::initialize() {
   _supports_cx8 = true;
   _supports_atomic_getset4 = true;
   _supports_atomic_getadd4 = true;
   _supports_atomic_getset8 = true;
   _supports_atomic_getadd8 = true;
 
-  getPsrInfo_stub(&_psr_info);
+  get_os_cpu_info();
 
   int dcache_line = VM_Version::dcache_line_size();
 
@@ -163,34 +98,6 @@ void VM_Version::get_processor_features() {
     ContendedPaddingWidth = dcache_line;
   }
 
-  uint64_t auxv = getauxval(AT_HWCAP);
-
-  char buf[512];
-
-  _features = auxv;
-
-  int cpu_lines = 0;
-  if (FILE *f = fopen("/proc/cpuinfo", "r")) {
-    char buf[128], *p;
-    while (fgets(buf, sizeof (buf), f) != NULL) {
-      if ((p = strchr(buf, ':')) != NULL) {
-        long v = strtol(p+1, NULL, 0);
-        if (strncmp(buf, "CPU implementer", sizeof "CPU implementer" - 1) == 0) {
-          _cpu = v;
-          cpu_lines++;
-        } else if (strncmp(buf, "CPU variant", sizeof "CPU variant" - 1) == 0) {
-          _variant = v;
-        } else if (strncmp(buf, "CPU part", sizeof "CPU part" - 1) == 0) {
-          if (_model != v)  _model2 = _model;
-          _model = v;
-        } else if (strncmp(buf, "CPU revision", sizeof "CPU revision" - 1) == 0) {
-          _revision = v;
-        }
-      }
-    }
-    fclose(f);
-  }
-
   // Enable vendor specific features
 
   // ThunderX
@@ -256,27 +163,28 @@ void VM_Version::get_processor_features() {
   }
 
   if (_cpu == CPU_ARM && (_model == 0xd07 || _model2 == 0xd07)) _features |= CPU_STXR_PREFETCH;
-  // If an olde style /proc/cpuinfo (cpu_lines == 1) then if _model is an A57 (0xd07)
+  // If an olde style /proc/cpuinfo (cores == 1) then if _model is an A57 (0xd07)
   // we assume the worst and assume we could be on a big little system and have
   // undisclosed A53 cores which we could be swapped to at any stage
-  if (_cpu == CPU_ARM && cpu_lines == 1 && _model == 0xd07) _features |= CPU_A53MAC;
+  if (_cpu == CPU_ARM && os::processor_count() == 1 && _model == 0xd07) _features |= CPU_A53MAC;
 
+  char buf[512];
   sprintf(buf, "0x%02x:0x%x:0x%03x:%d", _cpu, _variant, _model, _revision);
   if (_model2) sprintf(buf+strlen(buf), "(0x%03x)", _model2);
-  if (auxv & HWCAP_ASIMD) strcat(buf, ", simd");
-  if (auxv & HWCAP_CRC32) strcat(buf, ", crc");
-  if (auxv & HWCAP_AES)   strcat(buf, ", aes");
-  if (auxv & HWCAP_SHA1)  strcat(buf, ", sha1");
-  if (auxv & HWCAP_SHA2)  strcat(buf, ", sha256");
-  if (auxv & HWCAP_ATOMICS) strcat(buf, ", lse");
+  if (_features & CPU_ASIMD) strcat(buf, ", simd");
+  if (_features & CPU_CRC32) strcat(buf, ", crc");
+  if (_features & CPU_AES)   strcat(buf, ", aes");
+  if (_features & CPU_SHA1)  strcat(buf, ", sha1");
+  if (_features & CPU_SHA2)  strcat(buf, ", sha256");
+  if (_features & CPU_LSE)   strcat(buf, ", lse");
 
   _features_string = os::strdup(buf);
 
   if (FLAG_IS_DEFAULT(UseCRC32)) {
-    UseCRC32 = (auxv & HWCAP_CRC32) != 0;
+    UseCRC32 = (_features & CPU_CRC32) != 0;
   }
 
-  if (UseCRC32 && (auxv & HWCAP_CRC32) == 0) {
+  if (UseCRC32 && (_features & CPU_CRC32) == 0) {
     warning("UseCRC32 specified, but not supported on this CPU");
     FLAG_SET_DEFAULT(UseCRC32, false);
   }
@@ -290,7 +198,7 @@ void VM_Version::get_processor_features() {
     FLAG_SET_DEFAULT(UseVectorizedMismatchIntrinsic, false);
   }
 
-  if (auxv & HWCAP_ATOMICS) {
+  if (_features & CPU_LSE) {
     if (FLAG_IS_DEFAULT(UseLSE))
       FLAG_SET_DEFAULT(UseLSE, true);
   } else {
@@ -300,7 +208,7 @@ void VM_Version::get_processor_features() {
     }
   }
 
-  if (auxv & HWCAP_AES) {
+  if (_features & CPU_AES) {
     UseAES = UseAES || FLAG_IS_DEFAULT(UseAES);
     UseAESIntrinsics =
         UseAESIntrinsics || (UseAES && FLAG_IS_DEFAULT(UseAESIntrinsics));
@@ -328,7 +236,7 @@ void VM_Version::get_processor_features() {
     UseCRC32Intrinsics = true;
   }
 
-  if (auxv & HWCAP_CRC32) {
+  if (_features & CPU_CRC32) {
     if (FLAG_IS_DEFAULT(UseCRC32CIntrinsics)) {
       FLAG_SET_DEFAULT(UseCRC32CIntrinsics, true);
     }
@@ -341,7 +249,7 @@ void VM_Version::get_processor_features() {
     FLAG_SET_DEFAULT(UseFMA, true);
   }
 
-  if (auxv & (HWCAP_SHA1 | HWCAP_SHA2)) {
+  if (_features & (CPU_SHA1 | CPU_SHA2)) {
     if (FLAG_IS_DEFAULT(UseSHA)) {
       FLAG_SET_DEFAULT(UseSHA, true);
     }
@@ -350,7 +258,7 @@ void VM_Version::get_processor_features() {
     FLAG_SET_DEFAULT(UseSHA, false);
   }
 
-  if (UseSHA && (auxv & HWCAP_SHA1)) {
+  if (UseSHA && (_features & CPU_SHA1)) {
     if (FLAG_IS_DEFAULT(UseSHA1Intrinsics)) {
       FLAG_SET_DEFAULT(UseSHA1Intrinsics, true);
     }
@@ -359,7 +267,7 @@ void VM_Version::get_processor_features() {
     FLAG_SET_DEFAULT(UseSHA1Intrinsics, false);
   }
 
-  if (UseSHA && (auxv & HWCAP_SHA2)) {
+  if (UseSHA && (_features & CPU_SHA2)) {
     if (FLAG_IS_DEFAULT(UseSHA256Intrinsics)) {
       FLAG_SET_DEFAULT(UseSHA256Intrinsics, true);
     }
@@ -377,7 +285,7 @@ void VM_Version::get_processor_features() {
     FLAG_SET_DEFAULT(UseSHA, false);
   }
 
-  if (auxv & HWCAP_PMULL) {
+  if (_features & CPU_PMULL) {
     if (FLAG_IS_DEFAULT(UseGHASHIntrinsics)) {
       FLAG_SET_DEFAULT(UseGHASHIntrinsics, true);
     }
@@ -439,22 +347,6 @@ void VM_Version::get_processor_features() {
     OptoScheduling = true;
   }
 #endif
-}
-
-void VM_Version::initialize() {
-  ResourceMark rm;
-
-  stub_blob = BufferBlob::create("getPsrInfo_stub", stub_size);
-  if (stub_blob == NULL) {
-    vm_exit_during_initialization("Unable to allocate getPsrInfo_stub");
-  }
-
-  CodeBuffer c(stub_blob);
-  VM_Version_StubGenerator g(&c);
-  getPsrInfo_stub = CAST_TO_FN_PTR(getPsrInfo_stub_t,
-                                   g.generate_getPsrInfo());
-
-  get_processor_features();
 
   UNSUPPORTED_OPTION(CriticalJNINatives);
 }

src/hotspot/cpu/aarch64/vm_version_aarch64.hpp

@@ -41,12 +41,12 @@ class VM_Version : public Abstract_VM_Version {
   static int _revision;
   static int _stepping;
 
-  struct PsrInfo {
-    uint32_t dczid_el0;
-    uint32_t ctr_el0;
-  };
-  static PsrInfo _psr_info;
-  static void get_processor_features();
+  static int _zva_length;
+  static int _dcache_line_size;
+  static int _icache_line_size;
+
+  // Read additional info using OS-specific interfaces
+  static void get_os_cpu_info();
 
 public:
   // Initialization
@@ -91,6 +91,7 @@ class VM_Version : public Abstract_VM_Version {
     CPU_SHA2         = (1<<6),
     CPU_CRC32        = (1<<7),
     CPU_LSE          = (1<<8),
+    // flags above must follow Linux HWCAP
     CPU_STXR_PREFETCH= (1 << 29),
     CPU_A53MAC       = (1 << 30),
     CPU_DMB_ATOMICS  = (1 << 31),
@@ -101,24 +102,15 @@ class VM_Version : public Abstract_VM_Version {
   static int cpu_model2()                     { return _model2; }
   static int cpu_variant()                    { return _variant; }
   static int cpu_revision()                   { return _revision; }
-  static ByteSize dczid_el0_offset() { return byte_offset_of(PsrInfo, dczid_el0); }
-  static ByteSize ctr_el0_offset()   { return byte_offset_of(PsrInfo, ctr_el0); }
-  static bool is_zva_enabled() {
-    // Check the DZP bit (bit 4) of dczid_el0 is zero
-    // and block size (bit 0~3) is not zero.
-    return ((_psr_info.dczid_el0 & 0x10) == 0 &&
-            (_psr_info.dczid_el0 & 0xf) != 0);
-  }
+
+  static bool is_zva_enabled() { return 0 <= _zva_length; }
   static int zva_length() {
     assert(is_zva_enabled(), "ZVA not available");
-    return 4 << (_psr_info.dczid_el0 & 0xf);
-  }
-  static int icache_line_size() {
-    return (1 << (_psr_info.ctr_el0 & 0x0f)) * 4;
-  }
-  static int dcache_line_size() {
-    return (1 << ((_psr_info.ctr_el0 >> 16) & 0x0f)) * 4;
+    return _zva_length;
   }
+
+  static int icache_line_size() { return _icache_line_size; }
+  static int dcache_line_size() { return _dcache_line_size; }
 };
 
 #endif // CPU_AARCH64_VM_VM_VERSION_AARCH64_HPP