lrdp_v2 : Fix for memstat.py for 4.14 kernel

zram_index_idr Macro is changed for 4.14 onwards
and zram alloc data wasnt coming proper.

Change-Id: Ia637e4e4d5147e18319443cb732d1f1abf6010ab
Signed-off-by: avijayku <avijayku@codeaurora.org>

linux-ramdump-parser-v2/parsers/memstat.py

-# Copyright (c) 2016-2018 The Linux Foundation. All rights reserved.
+# Copyright (c) 2016-2019 The Linux Foundation. All rights reserved.
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License version 2 and
@@ -180,17 +180,24 @@ class MemStats(RamParser):
             kgsl_memory = 0
 
         # zcompressed ram
-        if self.ramdump.kernel_version >= (4, 14):
-            stat_val = 0
-        elif self.ramdump.kernel_version >= (4, 4):
-            zram_index_idr = self.ramdump.read_word('zram_index_idr')
+        if self.ramdump.kernel_version >= (4, 4):
+            if self.ramdump.kernel_version >= (4, 14):
+                zram_index_idr = self.ramdump.address_of('zram_index_idr')
+            else:
+                zram_index_idr = self.ramdump.read_word('zram_index_idr')
             if zram_index_idr is None:
                 stat_val = 0
             else:
-                idr_layer_ary_offset = self.ramdump.field_offset(
-                            'struct idr_layer', 'ary')
-                idr_layer_ary = self.ramdump.read_word(zram_index_idr +
+                if self.ramdump.kernel_version >= (4, 14):
+                    idr_layer_ary_offset = self.ramdump.field_offset(
+                            'struct radix_tree_root', 'rnode')
+                    idr_layer_ary = self.ramdump.read_word(zram_index_idr +
                                                    idr_layer_ary_offset)
+                else:
+                    idr_layer_ary_offset = self.ramdump.field_offset(
+                                'struct idr_layer', 'ary')
+                    idr_layer_ary = self.ramdump.read_word(zram_index_idr +
+                                                       idr_layer_ary_offset)
                 try:
                     zram_meta = idr_layer_ary + self.ramdump.field_offset(
                                     'struct zram', 'meta')