Merge "meminfo: handle multiple buffer references in dmabufinfo"

3 files changed, 58 insertions, 16 deletions

diff --git a/libmeminfo/libdmabufinfo/dmabufinfo.cpp b/libmeminfo/libdmabufinfo/dmabufinfo.cpp
index 41ecc5195..b4ad6678a 100644
--- a/libmeminfo/libdmabufinfo/dmabufinfo.cpp
+++ b/libmeminfo/libdmabufinfo/dmabufinfo.cpp
@@ -119,9 +119,23 @@ static bool ReadDmaBufFdRefs(pid_t pid, std::vector<DmaBuffer>* dmabufs) {
             return false;
         }
 
-        DmaBuffer& buf =
+        uint64_t inode = sb.st_ino;
+        auto buf = std::find_if(dmabufs->begin(), dmabufs->end(),
+                                [&inode](const DmaBuffer& dbuf) { return dbuf.inode() == inode; });
+        if (buf != dmabufs->end()) {
+            if (buf->name() == "" || buf->name() == "<unknown>")
+                buf->SetName(name);
+            if (buf->exporter() == "" || buf->exporter() == "<unknown>")
+                buf->SetExporter(exporter);
+            if (buf->count() == 0)
+                buf->SetCount(count);
+            buf->AddFdRef(pid);
+            return true;
+        }
+
+        DmaBuffer& db =
                 dmabufs->emplace_back(sb.st_ino, sb.st_blocks * 512, count, exporter, name);
-        buf.AddFdRef(pid);
+        db.AddFdRef(pid);
     }
 
     return true;
@@ -225,6 +239,10 @@ bool ReadDmaBufInfo(std::vector<DmaBuffer>* dmabufs, const std::string& path) {
 
 bool ReadDmaBufInfo(pid_t pid, std::vector<DmaBuffer>* dmabufs) {
     dmabufs->clear();
+    return AppendDmaBufInfo(pid, dmabufs);
+}
+
+bool AppendDmaBufInfo(pid_t pid, std::vector<DmaBuffer>* dmabufs) {
     if (!ReadDmaBufFdRefs(pid, dmabufs)) {
         LOG(ERROR) << "Failed to read dmabuf fd references";
         return false;
diff --git a/libmeminfo/libdmabufinfo/dmabufinfo_test.cpp b/libmeminfo/libdmabufinfo/dmabufinfo_test.cpp
index aa5f16c22..95aa2c799 100644
--- a/libmeminfo/libdmabufinfo/dmabufinfo_test.cpp
+++ b/libmeminfo/libdmabufinfo/dmabufinfo_test.cpp
@@ -21,6 +21,7 @@
 
 #include <string>
 #include <vector>
+#include <unordered_map>
 
 #include <android-base/file.h>
 #include <android-base/logging.h>
@@ -61,18 +62,16 @@ struct ion_heap_data {
 
 #define EXPECT_PID_IN_FDREFS(_bufptr, _pid, _expect)                         \
     do {                                                                     \
-        const std::vector<pid_t>& _fdrefs = _bufptr->fdrefs();               \
-        auto _ref = std::find_if(_fdrefs.begin(), _fdrefs.end(),             \
-                                 [&](const pid_t& p) { return p == _pid; }); \
-        EXPECT_EQ((_ref == _fdrefs.end()), _expect);                         \
+        const std::unordered_map<pid_t, int>& _fdrefs = _bufptr->fdrefs();   \
+        auto _ref = _fdrefs.find(_pid);                                      \
+        EXPECT_EQ((_ref != _fdrefs.end()), _expect);                         \
     } while (0)
 
 #define EXPECT_PID_IN_MAPREFS(_bufptr, _pid, _expect)                        \
     do {                                                                     \
-        const std::vector<pid_t>& _maprefs = _bufptr->maprefs();             \
-        auto _ref = std::find_if(_maprefs.begin(), _maprefs.end(),           \
-                                 [&](const pid_t& p) { return p == _pid; }); \
-        EXPECT_EQ((_ref == _maprefs.end()), _expect);                        \
+        const std::unordered_map<pid_t, int>& _maprefs = _bufptr->maprefs(); \
+        auto _ref = _maprefs.find(_pid);                                     \
+        EXPECT_EQ((_ref != _maprefs.end()), _expect);                        \
     } while (0)
 
 TEST(DmaBufInfoParser, TestReadDmaBufInfo) {
diff --git a/libmeminfo/libdmabufinfo/include/dmabufinfo/dmabufinfo.h b/libmeminfo/libdmabufinfo/include/dmabufinfo/dmabufinfo.h
index 29ce4d0bd..74eff3cca 100644
--- a/libmeminfo/libdmabufinfo/include/dmabufinfo/dmabufinfo.h
+++ b/libmeminfo/libdmabufinfo/include/dmabufinfo/dmabufinfo.h
@@ -21,6 +21,7 @@
 
 #include <string>
 #include <vector>
+#include <unordered_map>
 
 namespace android {
 namespace dmabufinfo {
@@ -33,20 +34,27 @@ struct DmaBuffer {
     ~DmaBuffer() = default;
 
     // Adds one file descriptor reference for the given pid
-    void AddFdRef(pid_t pid) { fdrefs_.emplace_back(pid); }
+    void AddFdRef(pid_t pid) {
+        AddRefToPidMap(pid, &fdrefs_);
+    }
 
     // Adds one map reference for the given pid
-    void AddMapRef(pid_t pid) { maprefs_.emplace_back(pid); }
+    void AddMapRef(pid_t pid) {
+        AddRefToPidMap(pid, &maprefs_);
+    }
 
     // Getters for each property
     uint64_t size() { return size_; }
-    const std::vector<pid_t>& fdrefs() const { return fdrefs_; }
-    const std::vector<pid_t>& maprefs() const { return maprefs_; }
+    const std::unordered_map<pid_t, int>& fdrefs() const { return fdrefs_; }
+    const std::unordered_map<pid_t, int>& maprefs() const { return maprefs_; }
     ino_t inode() const { return inode_; }
     uint64_t total_refs() const { return fdrefs_.size() + maprefs_.size(); }
     uint64_t count() const { return count_; };
     const std::string& name() const { return name_; }
     const std::string& exporter() const { return exporter_; }
+    void SetName(const std::string& name) { name_ = name; }
+    void SetExporter(const std::string& exporter) { exporter_ = exporter; }
+    void SetCount(uint64_t count) { count_ = count; }
 
   private:
     ino_t inode_;
@@ -54,20 +62,37 @@ struct DmaBuffer {
     uint64_t count_;
     std::string exporter_;
     std::string name_;
-    std::vector<pid_t> fdrefs_;
-    std::vector<pid_t> maprefs_;
+    std::unordered_map<pid_t, int> fdrefs_;
+    std::unordered_map<pid_t, int> maprefs_;
+    void AddRefToPidMap(pid_t pid, std::unordered_map<pid_t, int>* map) {
+        // The first time we find a ref, we set the ref count to 1
+        // otherwise, increment the existing ref count
+        auto [it, inserted] = map->insert(std::make_pair(pid, 1));
+        if (!inserted)
+            it->second++;
+    }
 };
 
 // Read and return current dma buf objects from
 // DEBUGFS/dma_buf/bufinfo. The references to each dma buffer are not
 // populated here and will return an empty vector.
+//
 // Returns false if something went wrong with the function, true otherwise.
 bool ReadDmaBufInfo(std::vector<DmaBuffer>* dmabufs,
                     const std::string& path = "/sys/kernel/debug/dma_buf/bufinfo");
 
+
 // Read and return dmabuf objects for a given process without the help
 // of DEBUGFS
+//
+// Returns false if something went wrong with the function, true otherwise.
 bool ReadDmaBufInfo(pid_t pid, std::vector<DmaBuffer>* dmabufs);
 
+// Append dmabuf objects for a given process without the help
+// of DEBUGFS to an existing vector
+//
+// Returns false if something went wrong with the function, true otherwise.
+bool AppendDmaBufInfo(pid_t pid, std::vector<DmaBuffer>* dmabufs);
+
 }  // namespace dmabufinfo
 }  // namespace android