[PATCH] memory tier: Remove unused default_dram_perf_ref_source

[Waiman Long]

Commit 3718c02dbd4c ("acpi, hmat: calculate abstract distance with HMAT")
added a default_dram_perf_ref_source variable that was initialized but
never used. This causes kmemleak to report the following memory leak:

unreferenced object 0xff11000225a47b60 (size 16):
  comm "swapper/0", pid 1, jiffies 4294761654
  hex dump (first 16 bytes):
    41 43 50 49 20 48 4d 41 54 00 c1 4b 7d b7 75 7c  ACPI HMAT..K}.u|
  backtrace (crc e6d0e7b2):
    [<ffffffff95d5afdb>] __kmalloc_node_track_caller_noprof+0x36b/0x440
    [<ffffffff95c276d6>] kstrdup+0x36/0x60
    [<ffffffff95dfabfa>] mt_set_default_dram_perf+0x23a/0x2c0
    [<ffffffff9ad64733>] hmat_init+0x2b3/0x660
    [<ffffffff95203cec>] do_one_initcall+0x11c/0x5c0
    [<ffffffff9ac9cfc4>] do_initcalls+0x1b4/0x1f0
    [<ffffffff9ac9d52e>] kernel_init_freeable+0x4ae/0x520
    [<ffffffff97c789cc>] kernel_init+0x1c/0x150
    [<ffffffff952aecd1>] ret_from_fork+0x31/0x70
    [<ffffffff9520b18a>] ret_from_fork_asm+0x1a/0x30

Fix this memory leak by removing default_dram_perf_ref_source.

Fixes: 3718c02dbd4c ("acpi, hmat: calculate abstract distance with HMAT")
Signed-off-by: Waiman Long <longman@xxxxxxxxxx>
---
 mm/memory-tiers.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/mm/memory-tiers.c b/mm/memory-tiers.c
index 4775b3a3dabe..baa5f20e3b78 100644
--- a/mm/memory-tiers.c
+++ b/mm/memory-tiers.c
@@ -119,7 +119,6 @@ static DEFINE_MUTEX(default_dram_perf_lock);
 static bool default_dram_perf_error;
 static struct access_coordinate default_dram_perf;
 static int default_dram_perf_ref_nid = NUMA_NO_NODE;
-static const char *default_dram_perf_ref_source;
 
 static inline struct memory_tier *to_memory_tier(struct device *device)
 {
@@ -728,7 +727,6 @@ int mt_set_default_dram_perf(int nid, struct access_coordinate *perf,
 	if (default_dram_perf_ref_nid == NUMA_NO_NODE) {
 		default_dram_perf = *perf;
 		default_dram_perf_ref_nid = nid;
-		default_dram_perf_ref_source = kstrdup(source, GFP_KERNEL);
 		return 0;
 	}
 
-- 
2.43.5