[kbuild-all] [intel-linux-intel-lts:4.19/preempt-rt 5/18] mm/zswap.c:995:30: warning: unused variable 'zswap_dstmem_lock'

tree: https://github.com/intel/linux-intel-lts.git 4.19/preempt-rt head: fe555b433eaef9bf08a98a527ed26759607a7879 commit: 7cf6c733c0aa7108e00a2ae809e3d2261a86a703 [5/18] Merge tag 'lts-v4.19.120-base-200512T132121Z' into lts2018/preempt-rt config: x86_64-randconfig-a004-20210521 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project e84a9b9bb3051c35dea993cdad7b3d2575638f85) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu # https://github.com/intel/linux-intel-lts/commit/7cf6c733c0aa7108e00a2ae80... git remote add intel-linux-intel-lts https://github.com/intel/linux-intel-lts.git git fetch --no-tags intel-linux-intel-lts 4.19/preempt-rt git checkout 7cf6c733c0aa7108e00a2ae809e3d2261a86a703 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): static DEFINE_LOCAL_IRQ_LOCK(zswap_dstmem_lock); ^ 1 warning generated. vim +/zswap_dstmem_lock +995 mm/zswap.c a85f878b443f8d2 Srividya Desireddy 2018-01-31 993 a9def13283a0cb8 Luis Claudio R. Goncalves 2019-06-25 994 /* protect zswap_dstmem from concurrency */ a9def13283a0cb8 Luis Claudio R. Goncalves 2019-06-25 @995 static DEFINE_LOCAL_IRQ_LOCK(zswap_dstmem_lock); 2b2811178e85553 Seth Jennings 2013-07-10 996 /********************************* 2b2811178e85553 Seth Jennings 2013-07-10 997 * frontswap hooks 2b2811178e85553 Seth Jennings 2013-07-10 998 **********************************/ 2b2811178e85553 Seth Jennings 2013-07-10 999 /* attempts to compress and store an single page */ 2b2811178e85553 Seth Jennings 2013-07-10 1000 static int zswap_frontswap_store(unsigned type, pgoff_t offset, 2b2811178e85553 Seth Jennings 2013-07-10 1001 struct page *page) 2b2811178e85553 Seth Jennings 2013-07-10 1002 { 2b2811178e85553 Seth Jennings 2013-07-10 1003 struct zswap_tree *tree = zswap_trees[type]; 2b2811178e85553 Seth Jennings 2013-07-10 1004 struct zswap_entry *entry, *dupentry; f1c54846ee4504d Dan Streetman 2015-09-09 1005 struct crypto_comp *tfm; 2b2811178e85553 Seth Jennings 2013-07-10 1006 int ret; 9c3760eb80880f3 Yu Zhao 2018-01-31 1007 unsigned int hlen, dlen = PAGE_SIZE; a85f878b443f8d2 Srividya Desireddy 2018-01-31 1008 unsigned long handle, value; 2b2811178e85553 Seth Jennings 2013-07-10 1009 char *buf; 2b2811178e85553 Seth Jennings 2013-07-10 1010 u8 *src, *dst; 9c3760eb80880f3 Yu Zhao 2018-01-31 1011 struct zswap_header zhdr = { .swpentry = swp_entry(type, offset) }; 2b2811178e85553 Seth Jennings 2013-07-10 1012 7ba716698cc53f8 Huang Ying 2018-02-21 1013 /* THP isn't supported */ 7ba716698cc53f8 Huang Ying 2018-02-21 1014 if (PageTransHuge(page)) { 7ba716698cc53f8 Huang Ying 2018-02-21 1015 ret = -EINVAL; 7ba716698cc53f8 Huang Ying 2018-02-21 1016 goto reject; 7ba716698cc53f8 Huang Ying 2018-02-21 1017 } 7ba716698cc53f8 Huang Ying 2018-02-21 1018 c00ed16a9eb98a7 Dan Streetman 2015-06-25 1019 if (!zswap_enabled || !tree) { 2b2811178e85553 Seth Jennings 2013-07-10 1020 ret = -ENODEV; 2b2811178e85553 Seth Jennings 2013-07-10 1021 goto reject; 2b2811178e85553 Seth Jennings 2013-07-10 1022 } 2b2811178e85553 Seth Jennings 2013-07-10 1023 2b2811178e85553 Seth Jennings 2013-07-10 1024 /* reclaim space if needed */ 2b2811178e85553 Seth Jennings 2013-07-10 1025 if (zswap_is_full()) { 2b2811178e85553 Seth Jennings 2013-07-10 1026 zswap_pool_limit_hit++; f1c54846ee4504d Dan Streetman 2015-09-09 1027 if (zswap_shrink()) { 2b2811178e85553 Seth Jennings 2013-07-10 1028 zswap_reject_reclaim_fail++; 2b2811178e85553 Seth Jennings 2013-07-10 1029 ret = -ENOMEM; 2b2811178e85553 Seth Jennings 2013-07-10 1030 goto reject; 2b2811178e85553 Seth Jennings 2013-07-10 1031 } 16e536ef47f5672 Li Wang 2018-07-26 1032 16e536ef47f5672 Li Wang 2018-07-26 1033 /* A second zswap_is_full() check after 16e536ef47f5672 Li Wang 2018-07-26 1034 * zswap_shrink() to make sure it's now 16e536ef47f5672 Li Wang 2018-07-26 1035 * under the max_pool_percent 16e536ef47f5672 Li Wang 2018-07-26 1036 */ 16e536ef47f5672 Li Wang 2018-07-26 1037 if (zswap_is_full()) { 16e536ef47f5672 Li Wang 2018-07-26 1038 ret = -ENOMEM; 16e536ef47f5672 Li Wang 2018-07-26 1039 goto reject; 16e536ef47f5672 Li Wang 2018-07-26 1040 } 2b2811178e85553 Seth Jennings 2013-07-10 1041 } 2b2811178e85553 Seth Jennings 2013-07-10 1042 2b2811178e85553 Seth Jennings 2013-07-10 1043 /* allocate entry */ 2b2811178e85553 Seth Jennings 2013-07-10 1044 entry = zswap_entry_cache_alloc(GFP_KERNEL); 2b2811178e85553 Seth Jennings 2013-07-10 1045 if (!entry) { 2b2811178e85553 Seth Jennings 2013-07-10 1046 zswap_reject_kmemcache_fail++; 2b2811178e85553 Seth Jennings 2013-07-10 1047 ret = -ENOMEM; 2b2811178e85553 Seth Jennings 2013-07-10 1048 goto reject; 2b2811178e85553 Seth Jennings 2013-07-10 1049 } 2b2811178e85553 Seth Jennings 2013-07-10 1050 a85f878b443f8d2 Srividya Desireddy 2018-01-31 1051 if (zswap_same_filled_pages_enabled) { a85f878b443f8d2 Srividya Desireddy 2018-01-31 1052 src = kmap_atomic(page); a85f878b443f8d2 Srividya Desireddy 2018-01-31 1053 if (zswap_is_page_same_filled(src, &value)) { a85f878b443f8d2 Srividya Desireddy 2018-01-31 1054 kunmap_atomic(src); a85f878b443f8d2 Srividya Desireddy 2018-01-31 1055 entry->offset = offset; a85f878b443f8d2 Srividya Desireddy 2018-01-31 1056 entry->length = 0; a85f878b443f8d2 Srividya Desireddy 2018-01-31 1057 entry->value = value; a85f878b443f8d2 Srividya Desireddy 2018-01-31 1058 atomic_inc(&zswap_same_filled_pages); a85f878b443f8d2 Srividya Desireddy 2018-01-31 1059 goto insert_entry; a85f878b443f8d2 Srividya Desireddy 2018-01-31 1060 } a85f878b443f8d2 Srividya Desireddy 2018-01-31 1061 kunmap_atomic(src); a85f878b443f8d2 Srividya Desireddy 2018-01-31 1062 } a85f878b443f8d2 Srividya Desireddy 2018-01-31 1063 f1c54846ee4504d Dan Streetman 2015-09-09 1064 /* if entry is successfully added, it keeps the reference */ f1c54846ee4504d Dan Streetman 2015-09-09 1065 entry->pool = zswap_pool_current_get(); f1c54846ee4504d Dan Streetman 2015-09-09 1066 if (!entry->pool) { f1c54846ee4504d Dan Streetman 2015-09-09 1067 ret = -EINVAL; f1c54846ee4504d Dan Streetman 2015-09-09 1068 goto freepage; f1c54846ee4504d Dan Streetman 2015-09-09 1069 } f1c54846ee4504d Dan Streetman 2015-09-09 1070 2b2811178e85553 Seth Jennings 2013-07-10 1071 /* compress */ a9def13283a0cb8 Luis Claudio R. Goncalves 2019-06-25 1072 dst = get_locked_var(zswap_dstmem_lock, zswap_dstmem); a9def13283a0cb8 Luis Claudio R. Goncalves 2019-06-25 1073 tfm = *this_cpu_ptr(entry->pool->tfm); 2b2811178e85553 Seth Jennings 2013-07-10 1074 src = kmap_atomic(page); f1c54846ee4504d Dan Streetman 2015-09-09 1075 ret = crypto_comp_compress(tfm, src, PAGE_SIZE, dst, &dlen); 2b2811178e85553 Seth Jennings 2013-07-10 1076 kunmap_atomic(src); 2b2811178e85553 Seth Jennings 2013-07-10 1077 if (ret) { 2b2811178e85553 Seth Jennings 2013-07-10 1078 ret = -EINVAL; f1c54846ee4504d Dan Streetman 2015-09-09 1079 goto put_dstmem; 2b2811178e85553 Seth Jennings 2013-07-10 1080 } 2b2811178e85553 Seth Jennings 2013-07-10 1081 2b2811178e85553 Seth Jennings 2013-07-10 1082 /* store */ 9c3760eb80880f3 Yu Zhao 2018-01-31 1083 hlen = zpool_evictable(entry->pool->zpool) ? sizeof(zhdr) : 0; 9c3760eb80880f3 Yu Zhao 2018-01-31 1084 ret = zpool_malloc(entry->pool->zpool, hlen + dlen, d0164adc89f6bb3 Mel Gorman 2015-11-06 1085 __GFP_NORETRY | __GFP_NOWARN | __GFP_KSWAPD_RECLAIM, d0164adc89f6bb3 Mel Gorman 2015-11-06 1086 &handle); 2b2811178e85553 Seth Jennings 2013-07-10 1087 if (ret == -ENOSPC) { 2b2811178e85553 Seth Jennings 2013-07-10 1088 zswap_reject_compress_poor++; f1c54846ee4504d Dan Streetman 2015-09-09 1089 goto put_dstmem; 2b2811178e85553 Seth Jennings 2013-07-10 1090 } 2b2811178e85553 Seth Jennings 2013-07-10 1091 if (ret) { 2b2811178e85553 Seth Jennings 2013-07-10 1092 zswap_reject_alloc_fail++; f1c54846ee4504d Dan Streetman 2015-09-09 1093 goto put_dstmem; 2b2811178e85553 Seth Jennings 2013-07-10 1094 } 9c3760eb80880f3 Yu Zhao 2018-01-31 1095 buf = zpool_map_handle(entry->pool->zpool, handle, ZPOOL_MM_RW); 9c3760eb80880f3 Yu Zhao 2018-01-31 1096 memcpy(buf, &zhdr, hlen); 9c3760eb80880f3 Yu Zhao 2018-01-31 1097 memcpy(buf + hlen, dst, dlen); f1c54846ee4504d Dan Streetman 2015-09-09 1098 zpool_unmap_handle(entry->pool->zpool, handle); a9def13283a0cb8 Luis Claudio R. Goncalves 2019-06-25 1099 put_locked_var(zswap_dstmem_lock, zswap_dstmem); 2b2811178e85553 Seth Jennings 2013-07-10 1100 2b2811178e85553 Seth Jennings 2013-07-10 1101 /* populate entry */ 2b2811178e85553 Seth Jennings 2013-07-10 1102 entry->offset = offset; 2b2811178e85553 Seth Jennings 2013-07-10 1103 entry->handle = handle; 2b2811178e85553 Seth Jennings 2013-07-10 1104 entry->length = dlen; 2b2811178e85553 Seth Jennings 2013-07-10 1105 a85f878b443f8d2 Srividya Desireddy 2018-01-31 1106 insert_entry: 2b2811178e85553 Seth Jennings 2013-07-10 1107 /* map */ 2b2811178e85553 Seth Jennings 2013-07-10 1108 spin_lock(&tree->lock); 2b2811178e85553 Seth Jennings 2013-07-10 1109 do { 2b2811178e85553 Seth Jennings 2013-07-10 1110 ret = zswap_rb_insert(&tree->rbroot, entry, &dupentry); 2b2811178e85553 Seth Jennings 2013-07-10 1111 if (ret == -EEXIST) { 2b2811178e85553 Seth Jennings 2013-07-10 1112 zswap_duplicate_entry++; 2b2811178e85553 Seth Jennings 2013-07-10 1113 /* remove from rbtree */ 0ab0abcf511545d Weijie Yang 2013-11-12 1114 zswap_rb_erase(&tree->rbroot, dupentry); 0ab0abcf511545d Weijie Yang 2013-11-12 1115 zswap_entry_put(tree, dupentry); 2b2811178e85553 Seth Jennings 2013-07-10 1116 } 2b2811178e85553 Seth Jennings 2013-07-10 1117 } while (ret == -EEXIST); 2b2811178e85553 Seth Jennings 2013-07-10 1118 spin_unlock(&tree->lock); 2b2811178e85553 Seth Jennings 2013-07-10 1119 2b2811178e85553 Seth Jennings 2013-07-10 1120 /* update stats */ 2b2811178e85553 Seth Jennings 2013-07-10 1121 atomic_inc(&zswap_stored_pages); f1c54846ee4504d Dan Streetman 2015-09-09 1122 zswap_update_total_size(); 2b2811178e85553 Seth Jennings 2013-07-10 1123 2b2811178e85553 Seth Jennings 2013-07-10 1124 return 0; 2b2811178e85553 Seth Jennings 2013-07-10 1125 f1c54846ee4504d Dan Streetman 2015-09-09 1126 put_dstmem: a9def13283a0cb8 Luis Claudio R. Goncalves 2019-06-25 1127 put_locked_var(zswap_dstmem_lock, zswap_dstmem); f1c54846ee4504d Dan Streetman 2015-09-09 1128 zswap_pool_put(entry->pool); f1c54846ee4504d Dan Streetman 2015-09-09 1129 freepage: 2b2811178e85553 Seth Jennings 2013-07-10 1130 zswap_entry_cache_free(entry); 2b2811178e85553 Seth Jennings 2013-07-10 1131 reject: 2b2811178e85553 Seth Jennings 2013-07-10 1132 return ret; 2b2811178e85553 Seth Jennings 2013-07-10 1133 } 2b2811178e85553 Seth Jennings 2013-07-10 1134 :::::: The code at line 995 was first introduced by commit :::::: a9def13283a0cb8a1ae98f4efb20d77279f4383d mm/zswap: Do not disable preemption in zswap_frontswap_store() :::::: TO: Luis Claudio R. Goncalves <lclaudio(a)uudg.org&gt; :::::: CC: Andrew kim <andrew.kim(a)intel.com&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org