[EagerAppCDS] enable classpath change by replacing given env var

Summary: If user give environment vars and use `-Dcom.alibaba.cds.cp.reloc.envs`, cds will change the classpath by using given environment vars to transform some paths in classpath. Test Plan: ci jtreg jdk/test/com/alibaba/quickstart/TestEnvVariableReplay.java jdk/test/com/alibaba/quickstart/TestEnvVariableDump.java Reviewed-by: lingjun-cg, yuleil Issue: #595
dragonwell-project · Oct 19, 2023 · 6284cfd · 6284cfd
1 parent e000397
commit 6284cfd
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Showing 9 changed files with 461 additions and 102 deletions.
diff --git a/hotspot/src/share/vm/classfile/sharedClassUtil.cpp b/hotspot/src/share/vm/classfile/sharedClassUtil.cpp
@@ -38,6 +38,7 @@
 #include "runtime/arguments.hpp"
 #include "runtime/java.hpp"
 #include "runtime/os.hpp"
+#include "runtime/quickStart.hpp"
 
 
 class ManifestStream: public ResourceObj {
@@ -156,56 +157,69 @@ ClassPathSegment* SharedPathsMiscInfoExt::to_sorted_segments(const char* path, i
   return cps;
 }
 
+bool SharedPathsMiscInfoExt::checkAPP(const char* path) {
+  size_t len = strlen(path);
+  const char *appcp = Arguments::get_appclasspath();
+  assert(appcp != NULL, "NULL app classpath");
+  size_t appcp_len = strlen(appcp);
+  if (appcp_len < len) {
+    return fail("Run time APP classpath is shorter than the one at dump time: ", appcp);
+  }
+  // Prefix is OK: E.g., dump with -cp foo.jar, but run with -cp foo.jar:bar.jar
+  if (AppCDSVerifyClassPathOrder) {
+    if (strncmp(path, appcp, len) != 0) {
+      return fail("[APP classpath mismatch, actual: -Djava.class.path=", appcp);
+    }
+    if (appcp[len] != '\0' && appcp[len] != os::path_separator()[0]) {
+      return fail("Dump time APP classpath is not a proper prefix of run time APP classpath: ", appcp);
+    }
+  } else{
+    ResourceMark rm;
+    int app_seg_num = 0;
+    int path_seg_num = 0;
+    ClassPathSegment* app_cps = to_sorted_segments(appcp, app_seg_num);
+    ClassPathSegment* path_cps = to_sorted_segments(path, path_seg_num);
+    if (app_seg_num < path_seg_num) {
+      return fail("[APP classpath mismatch, actual: -Djava.class.path=", appcp);
+    } else {
+      int i = 0, j = 0;
+      while(i < path_seg_num && j < app_seg_num){
+        if (app_cps[j]._len != path_cps[i]._len){
+          j++;
+        } else {
+          int c = strncmp(app_cps[j]._start, path_cps[i]._start, app_cps[j]._len);
+          if (c == 0) {
+            i++;
+            j++;
+          } else if (c < 0) {
+            j++;
+          } else {
+            break;
+          }
+        }
+      }
+      if (i != path_seg_num) {
+        return fail("[APP classpath mismatch, actual: -Djava.class.path=", appcp);
+      }
+    }
+  }
+  return true;
+}
 
 bool SharedPathsMiscInfoExt::check(jint type, const char* path) {
-
   switch (type) {
   case APP:
     {
-      size_t len = strlen(path);
-      const char *appcp = Arguments::get_appclasspath();
-      assert(appcp != NULL, "NULL app classpath");
-      size_t appcp_len = strlen(appcp);
-      if (appcp_len < len) {
-        return fail("Run time APP classpath is shorter than the one at dump time: ", appcp);
-      }
-      // Prefix is OK: E.g., dump with -cp foo.jar, but run with -cp foo.jar:bar.jar
-      if (AppCDSVerifyClassPathOrder) {
-        if (strncmp(path, appcp, len) != 0) {
-          return fail("[APP classpath mismatch, actual: -Djava.class.path=", appcp);
-        }
-        if (appcp[len] != '\0' && appcp[len] != os::path_separator()[0]) {
-          return fail("Dump time APP classpath is not a proper prefix of run time APP classpath: ", appcp);
-        }
-      } else{
-        ResourceMark rm;
-        int app_seg_num = 0;
-        int path_seg_num = 0;
-        ClassPathSegment* app_cps = to_sorted_segments(appcp, app_seg_num);
-        ClassPathSegment* path_cps = to_sorted_segments(path, path_seg_num);
-        if (app_seg_num < path_seg_num) {
-          return fail("[APP classpath mismatch, actual: -Djava.class.path=", appcp);
-        } else {
-          int i = 0, j = 0;
-          while(i < path_seg_num && j < app_seg_num){
-            if (app_cps[j]._len != path_cps[i]._len){
-              j++;
-            } else {
-              int c = strncmp(app_cps[j]._start, path_cps[i]._start, app_cps[j]._len);
-              if (c == 0) {
-                i++;
-                j++;
-              } else if (c < 0) {
-                j++;
-              } else {
-                break;
-              }
-            }
-          }
-          if (i != path_seg_num) {
-            return fail("[APP classpath mismatch, actual: -Djava.class.path=", appcp);
-          }
-        }
+      if (QuickStart::need_convert_path_by_env()) {
+        int new_path_len = QuickStart::get_max_replaced_path_len(path) + 1;
+        char* new_path = NEW_C_HEAP_ARRAY(char, new_path_len, mtInternal);
+        QuickStart::convert_path_by_env(path, new_path);
+        ClassLoader::trace_class_path(tty, "new_path: ", new_path);
+        bool result = checkAPP(new_path);
+        FREE_C_HEAP_ARRAY(char, new_path, mtInternal);
+        return result;
+      } else {
+        return checkAPP(path);
       }
     }
     break;

diff --git a/hotspot/src/share/vm/classfile/sharedClassUtil.hpp b/hotspot/src/share/vm/classfile/sharedClassUtil.hpp
@@ -82,6 +82,8 @@ class SharedPathsMiscInfoExt : public SharedPathsMiscInfo {
 
   virtual bool check(jint type, const char* path);
 
+  virtual bool checkAPP(const char* path);
+
   void add_app_classpath(const char* path) {
     add_path(path, APP);
   }

diff --git a/hotspot/src/share/vm/memory/filemap.cpp b/hotspot/src/share/vm/memory/filemap.cpp
@@ -34,6 +34,7 @@
 #include "oops/objArrayOop.hpp"
 #include "runtime/arguments.hpp"
 #include "runtime/java.hpp"
+#include "runtime/quickStart.hpp"
 #include "runtime/os.hpp"
 #include "services/memTracker.hpp"
 #include "utilities/defaultStream.hpp"
@@ -264,6 +265,13 @@ bool FileMapInfo::validate_classpath_entry_table() {
     SharedClassPathEntry* ent = shared_classpath(i);
     struct stat st;
     const char* name = ent->_name;
+    char* new_ent_name = QuickStart::replace_if_contains(name);
+    if (new_ent_name != NULL) {
+      if (TraceClassPaths || (TraceClassLoading && Verbose)) {
+        tty->print_cr("replace %s with %s", name, new_ent_name);
+      }
+      name = new_ent_name;
+    }
     bool ok = true;
     if (TraceClassPaths || (TraceClassLoading && Verbose)) {
       tty->print_cr("[Checking shared classpath entry: %s]", name);
@@ -277,7 +285,7 @@ bool FileMapInfo::validate_classpath_entry_table() {
         ok = false;
       }
     } else {
-      if (ent->_timestamp != st.st_mtime ||
+      if ((ent->_timestamp != st.st_mtime && !CDSIgnoreFileTimeCheck) ||
           ent->_filesize != st.st_size) {
         ok = false;
         if (PrintSharedArchiveAndExit) {
@@ -290,6 +298,9 @@ bool FileMapInfo::validate_classpath_entry_table() {
         }
       }
     }
+    if (new_ent_name != NULL) {
+      FREE_C_HEAP_ARRAY(char, new_ent_name, mtInternal);
+    }
     if (ok) {
       if (TraceClassPaths || (TraceClassLoading && Verbose)) {
         tty->print_cr("[ok]");

diff --git a/hotspot/src/share/vm/runtime/globals_ext.hpp b/hotspot/src/share/vm/runtime/globals_ext.hpp
@@ -174,6 +174,8 @@
           "Ignore non-empty dir check in AppCDS")                           \
   product(bool, CDSIgnoreBootClasspathDiff, false,                        \
           "keep AppCDS on after appending boot classpath")                  \
+  product(bool, CDSIgnoreFileTimeCheck, false,                           \
+          "do not check timestamp of jar file when using CDS")              \
                                                                             \
   product(bool, SuppressAppCDSErrors, false,                                \
           "Suppress AppCDS errors during initialization; use warnings instead") \