Memtrack HAL: Update documentation
Detail what is expected to be returned by the different memtrack types.
Add what the device name is expected to be in getGpuDeviceInfo()
Bug: 181704406
Test: N/A
Change-Id: I5e9fe0bf5e630a8a0ec8394fa4f508657e4a56a7
diff --git a/memtrack/aidl/android/hardware/memtrack/IMemtrack.aidl b/memtrack/aidl/android/hardware/memtrack/IMemtrack.aidl
index 18587ee..e78d4d7 100644
--- a/memtrack/aidl/android/hardware/memtrack/IMemtrack.aidl
+++ b/memtrack/aidl/android/hardware/memtrack/IMemtrack.aidl
@@ -30,6 +30,22 @@
* GL, graphics, etc. All memory sizes must be in real memory usage,
* accounting for stride, bit depth, rounding up to page size, etc.
*
+ * The following getMemory() categories are important for memory accounting in
+ * `dumpsys meminfo` and should be reported as described below:
+ *
+ * - MemtrackType::GRAPHICS and MemtrackRecord::FLAG_SMAPS_UNACCOUNTED
+ * This should report the PSS of all DMA buffers mapped by the process
+ * with the specified PID. This PSS can be calculated using ReadDmaBufPss()
+ * form libdmabufinfo.
+ *
+ * - MemtrackType::GL and MemtrackRecord::FLAG_SMAPS_UNACCOUNTED
+ * This category should report all GPU private allocations for the specified
+ * PID that are not accounted in /proc/<pid>/smaps.
+ *
+ * - MemtrackType::OTHER and MemtrackRecord::FLAG_SMAPS_UNACCOUNTED
+ * Any other memory not accounted for in /proc/<pid>/smaps if any, otherwise
+ * this should return 0.
+ *
* Constructor for the interface should be used to perform memtrack management
* setup actions and must be called once before any calls to getMemory().
*/
@@ -76,7 +92,10 @@
* This information is used to identify GPU devices for GPU specific
* memory accounting (e.g. DMA buffer usage).
*
+ * The device name(s) provided in getGpuDeviceInfo() must match the
+ * device name in the corresponding device(s) sysfs entry.
+ *
* @return vector of DeviceInfo populated for all GPU devices.
*/
- DeviceInfo[] getGpuDeviceInfo();
+ DeviceInfo[] getGpuDeviceInfo();
}