Merge "Implement malloc_info(3)."

libc/Android.mk

@@ -135,6 +135,7 @@ libc_bionic_src_files := \
     bionic/link.cpp \
     bionic/locale.cpp \
     bionic/lstat.cpp \
+    bionic/malloc_info.cpp \
     bionic/mbrtoc16.cpp \
     bionic/mbrtoc32.cpp \
     bionic/mbstate.cpp \

libc/bionic/dlmalloc.c

@@ -16,6 +16,7 @@
 
 #include "dlmalloc.h"
 
+#include "malloc.h"
 #include "private/bionic_prctl.h"
 #include "private/libc_logging.h"
 
@@ -54,3 +55,25 @@ static void* named_anonymous_mmap(size_t length) {
   prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, map, length, "libc_malloc");
   return map;
 }
+
+// Since dlmalloc isn't the default, we'll leave this unimplemented for now. If
+// we decide we need it later, we can fill it in.
+size_t __mallinfo_narenas() {
+  return 0;
+}
+
+size_t __mallinfo_nbins() {
+  return 0;
+}
+
+struct mallinfo __mallinfo_arena_info(size_t) {
+  struct mallinfo mi;
+  memset(&mi, 0, sizeof(mi));
+  return mi;
+}
+
+struct mallinfo __mallinfo_bin_info(size_t, size_t) {
+  struct mallinfo mi;
+  memset(&mi, 0, sizeof(mi));
+  return mi;
+}

libc/bionic/malloc_info.cpp

@@ -0,0 +1,94 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "malloc_info.h"
+
+#include <errno.h>
+#include "private/bionic_macros.h"
+
+class __LIBC_HIDDEN__ Elem {
+public:
+  // name must be valid throughout lifetime of the object.
+  explicit Elem(FILE* fp, const char* name,
+                const char* attr_fmt = nullptr, ...) {
+    this->fp = fp;
+    this->name = name;
+
+    fprintf(fp, "<%s", name);
+    if (attr_fmt != nullptr) {
+      va_list args;
+      va_start(args, attr_fmt);
+      fputc(' ', fp);
+      vfprintf(fp, attr_fmt, args);
+      va_end(args);
+    }
+    fputc('>', fp);
+  }
+
+  ~Elem() noexcept {
+    fprintf(fp, "</%s>", name);
+  }
+
+  void contents(const char* fmt, ...) {
+      va_list args;
+      va_start(args, fmt);
+      vfprintf(fp, fmt, args);
+      va_end(args);
+  }
+
+private:
+  FILE* fp;
+  const char* name;
+
+  DISALLOW_COPY_AND_ASSIGN(Elem);
+};
+
+int malloc_info(int options, FILE* fp) {
+  if (options != 0) {
+    errno = EINVAL;
+    return -1;
+  }
+
+  Elem root(fp, "malloc", "version=\"jemalloc-1\"");
+
+  // Dump all of the large allocations in the arenas.
+  for (size_t i = 0; i < __mallinfo_narenas(); i++) {
+    struct mallinfo mi = __mallinfo_arena_info(i);
+    if (mi.hblkhd != 0) {
+      Elem arena_elem(fp, "heap", "nr=\"%d\"", i);
+      {
+        Elem(fp, "allocated-large").contents("%zu", mi.ordblks);
+        Elem(fp, "allocated-huge").contents("%zu", mi.uordblks);
+        Elem(fp, "allocated-bins").contents("%zu", mi.fsmblks);
+
+        size_t total = 0;
+        for (size_t j = 0; j < __mallinfo_nbins(); j++) {
+          struct mallinfo mi = __mallinfo_bin_info(i, j);
+          if (mi.ordblks != 0) {
+            Elem bin_elem(fp, "bin", "nr=\"%d\"", j);
+            Elem(fp, "allocated").contents("%zu", mi.ordblks);
+            Elem(fp, "nmalloc").contents("%zu", mi.uordblks);
+            Elem(fp, "ndalloc").contents("%zu", mi.fordblks);
+            total += mi.ordblks;
+          }
+        }
+        Elem(fp, "bins-total").contents("%zu", total);
+      }
+    }
+  }
+
+  return 0;
+}

libc/bionic/malloc_info.h

@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef LIBC_BIONIC_MALLOC_INFO_H_
+#define LIBC_BIONIC_MALLOC_INFO_H_
+
+#include <malloc.h>
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+__LIBC_HIDDEN__ size_t __mallinfo_narenas();
+__LIBC_HIDDEN__ size_t __mallinfo_nbins();
+__LIBC_HIDDEN__ struct mallinfo __mallinfo_arena_info(size_t);
+__LIBC_HIDDEN__ struct mallinfo __mallinfo_bin_info(size_t, size_t);
+
+__END_DECLS
+
+#endif // LIBC_BIONIC_MALLOC_INFO_H_

libc/include/malloc.h

@@ -24,6 +24,7 @@
  */
 #include <sys/cdefs.h>
 #include <stddef.h>
+#include <stdio.h>
 
 __BEGIN_DECLS
 
@@ -53,6 +54,27 @@ struct mallinfo {
 
 extern struct mallinfo mallinfo(void);
 
+/*
+ * XML structure for malloc_info(3) is in the following format:
+ *
+ * <malloc version="jemalloc-1">
+ *   <heap nr="INT">
+ *     <allocated-large>INT</allocated-large>
+ *     <allocated-huge>INT</allocated-huge>
+ *     <allocated-bins>INT</allocated-bins>
+ *     <bins-total>INT</bins-total>
+ *     <bin nr="INT">
+ *       <allocated>INT</allocated>
+ *       <nmalloc>INT</nmalloc>
+ *       <ndalloc>INT</ndalloc>
+ *     </bin>
+ *     <!-- more bins -->
+ *   </heap>
+ *   <!-- more heaps -->
+ * </malloc>
+ */
+extern int malloc_info(int, FILE *);
+
 __END_DECLS
 
 #endif  /* LIBC_INCLUDE_MALLOC_H_ */

tests/Android.mk

@@ -130,6 +130,7 @@ libBionicStandardTests_cppflags := \
 
 libBionicStandardTests_c_includes := \
     bionic/libc \
+    external/tinyxml2 \
 
 libBionicStandardTests_ldlibs_host := \
     -lrt \
@@ -243,6 +244,10 @@ include $(LOCAL_PATH)/Android.build.mk
 bionic-unit-tests_whole_static_libraries := \
     libBionicTests \
 
+bionic-unit-tests_static_libraries := \
+    libtinyxml2 \
+    liblog \
+
 bionic-unit-tests_src_files := \
     atexit_test.cpp \
     dlext_test.cpp \
@@ -280,6 +285,8 @@ bionic-unit-tests-static_static_libraries := \
     libm \
     libc \
     libstdc++ \
+    libtinyxml2 \
+    liblog \
 
 bionic-unit-tests-static_force_static_executable := true
 

tests/malloc_test.cpp

@@ -22,6 +22,8 @@
 #include <malloc.h>
 #include <unistd.h>
 
+#include <tinyxml2.h>
+
 #include "private/bionic_config.h"
 
 TEST(malloc, malloc_std) {
@@ -322,3 +324,51 @@ TEST(malloc, valloc_overflow) {
   ASSERT_EQ(NULL, valloc(SIZE_MAX));
 }
 #endif
+
+TEST(malloc, malloc_info) {
+#ifdef __BIONIC__
+  char* buf;
+  size_t bufsize;
+  FILE* memstream = open_memstream(&buf, &bufsize);
+  ASSERT_NE(nullptr, memstream);
+  ASSERT_EQ(0, malloc_info(0, memstream));
+  ASSERT_EQ(0, fclose(memstream));
+
+  tinyxml2::XMLDocument doc;
+  ASSERT_EQ(tinyxml2::XML_SUCCESS, doc.Parse(buf));
+
+  auto root = doc.FirstChildElement();
+  ASSERT_NE(nullptr, root);
+  ASSERT_STREQ("malloc", root->Name());
+  ASSERT_STREQ("jemalloc-1", root->Attribute("version"));
+
+  auto arena = root->FirstChildElement();
+  for (; arena != nullptr; arena = arena->NextSiblingElement()) {
+    int val;
+
+    ASSERT_STREQ("heap", arena->Name());
+    ASSERT_EQ(tinyxml2::XML_SUCCESS, arena->QueryIntAttribute("nr", &val));
+    ASSERT_EQ(tinyxml2::XML_SUCCESS,
+              arena->FirstChildElement("allocated-large")->QueryIntText(&val));
+    ASSERT_EQ(tinyxml2::XML_SUCCESS,
+              arena->FirstChildElement("allocated-huge")->QueryIntText(&val));
+    ASSERT_EQ(tinyxml2::XML_SUCCESS,
+              arena->FirstChildElement("allocated-bins")->QueryIntText(&val));
+    ASSERT_EQ(tinyxml2::XML_SUCCESS,
+              arena->FirstChildElement("bins-total")->QueryIntText(&val));
+
+    auto bin = arena->FirstChildElement("bin");
+    for (; bin != nullptr; bin = bin ->NextSiblingElement()) {
+      if (strcmp(bin->Name(), "bin") == 0) {
+        ASSERT_EQ(tinyxml2::XML_SUCCESS, bin->QueryIntAttribute("nr", &val));
+        ASSERT_EQ(tinyxml2::XML_SUCCESS,
+                  bin->FirstChildElement("allocated")->QueryIntText(&val));
+        ASSERT_EQ(tinyxml2::XML_SUCCESS,
+                  bin->FirstChildElement("nmalloc")->QueryIntText(&val));
+        ASSERT_EQ(tinyxml2::XML_SUCCESS,
+                  bin->FirstChildElement("ndalloc")->QueryIntText(&val));
+      }
+    }
+  }
+#endif
+}