Hi Kanchana, kernel test robot noticed the following build warnings: [auto build test WARNING on 5a7056135bb69da2ce0a42eb8c07968c1331777b] url: https://github.com/intel-lab-lkp/linux/commits/Kanchana-P-Sridhar/crypto-acomp-Define-two-new-interfaces-for-compress-decompress-batching/20241125-110412 base: 5a7056135bb69da2ce0a42eb8c07968c1331777b patch link: https://lore.kernel.org/r/20241123070127.332773-11-kanchana.p.sridhar%40intel.com patch subject: [PATCH v4 10/10] mm: zswap: Compress batching with Intel IAA in zswap_batch_store() of large folios. config: x86_64-buildonly-randconfig-003-20241125 (https://download.01.org/0day-ci/archive/20241125/202411251534.ETkkSgz6-lkp@xxxxxxxxx/config) compiler: clang version 19.1.3 (https://github.com/llvm/llvm-project ab51eccf88f5321e7c60591c5546b254b6afab99) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241125/202411251534.ETkkSgz6-lkp@xxxxxxxxx/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202411251534.ETkkSgz6-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): In file included from mm/zswap.c:18: In file included from include/linux/highmem.h:8: In file included from include/linux/cacheflush.h:5: In file included from arch/x86/include/asm/cacheflush.h:5: In file included from include/linux/mm.h:2211: include/linux/vmstat.h:518:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion] 518 | return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_" | ~~~~~~~~~~~ ^ ~~~ In file included from mm/zswap.c:40: In file included from mm/internal.h:13: include/linux/mm_inline.h:47:41: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion] 47 | __mod_lruvec_state(lruvec, NR_LRU_BASE + lru, nr_pages); | ~~~~~~~~~~~ ^ ~~~ include/linux/mm_inline.h:49:22: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum lru_list') [-Wenum-enum-conversion] 49 | NR_ZONE_LRU_BASE + lru, nr_pages); | ~~~~~~~~~~~~~~~~ ^ ~~~ >> mm/zswap.c:2315:8: warning: variable 'ret' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized] 2315 | if (memcg_list_lru_alloc(memcg, &zswap_list_lru, GFP_KERNEL)) { | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ mm/zswap.c:2335:8: note: uninitialized use occurs here 2335 | if (!ret && zswap_pool_reached_full) | ^~~ mm/zswap.c:2315:4: note: remove the 'if' if its condition is always false 2315 | if (memcg_list_lru_alloc(memcg, &zswap_list_lru, GFP_KERNEL)) { | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 2316 | mem_cgroup_put(memcg); | ~~~~~~~~~~~~~~~~~~~~~~ 2317 | goto put_objcg; | ~~~~~~~~~~~~~~~ 2318 | } | ~ mm/zswap.c:2310:7: warning: variable 'ret' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized] 2310 | if (zswap_check_limits()) | ^~~~~~~~~~~~~~~~~~~~ mm/zswap.c:2335:8: note: uninitialized use occurs here 2335 | if (!ret && zswap_pool_reached_full) | ^~~ mm/zswap.c:2310:3: note: remove the 'if' if its condition is always false 2310 | if (zswap_check_limits()) | ^~~~~~~~~~~~~~~~~~~~~~~~~ 2311 | goto put_objcg; | ~~~~~~~~~~~~~~ mm/zswap.c:2303:8: warning: variable 'ret' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized] 2303 | if (shrink_memcg(memcg)) { | ^~~~~~~~~~~~~~~~~~~ mm/zswap.c:2335:8: note: uninitialized use occurs here 2335 | if (!ret && zswap_pool_reached_full) | ^~~ mm/zswap.c:2303:4: note: remove the 'if' if its condition is always false 2303 | if (shrink_memcg(memcg)) { | ^~~~~~~~~~~~~~~~~~~~~~~~~~ 2304 | mem_cgroup_put(memcg); | ~~~~~~~~~~~~~~~~~~~~~~ 2305 | goto put_objcg; | ~~~~~~~~~~~~~~~ 2306 | } | ~ mm/zswap.c:2295:11: note: initialize the variable 'ret' to silence this warning 2295 | bool ret; | ^ | = 0 6 warnings generated. vim +2315 mm/zswap.c 2216 2217 /* 2218 * Store a large folio and/or a batch of any-order folio(s) in zswap 2219 * using IAA compress batching API. 2220 * 2221 * This the main procedure for batching within large folios and for batching 2222 * of folios. Each large folio will be broken into sub-batches of 2223 * SWAP_CRYPTO_BATCH_SIZE pages, the sub-batch pages will be compressed by 2224 * IAA hardware compress engines in parallel, then stored in zpool/xarray. 2225 * 2226 * This procedure should only be called if zswap supports batching of stores. 2227 * Otherwise, the sequential implementation for storing folios as in the 2228 * current zswap_store() should be used. The code handles the unlikely event 2229 * that the zswap pool changes from batching to non-batching between 2230 * swap_writepage() and the start of zswap_batch_store(). 2231 * 2232 * The signature of this procedure is meant to allow the calling function, 2233 * (for instance, swap_writepage()) to pass a batch of folios @batch 2234 * (the "reclaim batch") to be stored in zswap. 2235 * 2236 * @batch and @errors have folio_batch_count(@batch) number of entries, 2237 * with one-one correspondence (@errors[i] represents the error status of 2238 * @batch->folios[i], for i in folio_batch_count(@batch)). Please also 2239 * see comments preceding "struct zswap_batch_store_sub_batch" definition 2240 * above. 2241 * 2242 * The calling function (for instance, swap_writepage()) should initialize 2243 * @errors[i] to a non-0 value. 2244 * If zswap successfully stores @batch->folios[i], it will set @errors[i] to 0. 2245 * If there is an error in zswap, it will set @errors[i] to -EINVAL. 2246 * 2247 * @batch: folio_batch of folios to be batch compressed. 2248 * @errors: zswap_batch_store() error status for the folios in @batch. 2249 */ 2250 void zswap_batch_store(struct folio_batch *batch, int *errors) 2251 { 2252 struct zswap_batch_store_sub_batch sub_batch; 2253 struct zswap_pool *pool; 2254 u8 i; 2255 2256 /* 2257 * If zswap is disabled, we must invalidate the possibly stale entry 2258 * which was previously stored at this offset. Otherwise, writeback 2259 * could overwrite the new data in the swapfile. 2260 */ 2261 if (!zswap_enabled) 2262 goto check_old; 2263 2264 pool = zswap_pool_current_get(); 2265 2266 if (!pool) { 2267 if (zswap_check_limits()) 2268 queue_work(shrink_wq, &zswap_shrink_work); 2269 goto check_old; 2270 } 2271 2272 if (!pool->can_batch) { 2273 for (i = 0; i < folio_batch_count(batch); ++i) 2274 if (zswap_store(batch->folios[i])) 2275 errors[i] = 0; 2276 else 2277 errors[i] = -EINVAL; 2278 /* 2279 * Seems preferable to release the pool ref after the calls to 2280 * zswap_store(), so that the non-batching pool cannot be 2281 * deleted, can be used for sequential stores, and the zswap pool 2282 * cannot morph into a batching pool. 2283 */ 2284 zswap_pool_put(pool); 2285 return; 2286 } 2287 2288 zswap_batch_reset(&sub_batch); 2289 sub_batch.pool = pool; 2290 2291 for (i = 0; i < folio_batch_count(batch); ++i) { 2292 struct folio *folio = batch->folios[i]; 2293 struct obj_cgroup *objcg = NULL; 2294 struct mem_cgroup *memcg = NULL; 2295 bool ret; 2296 2297 VM_WARN_ON_ONCE(!folio_test_locked(folio)); 2298 VM_WARN_ON_ONCE(!folio_test_swapcache(folio)); 2299 2300 objcg = get_obj_cgroup_from_folio(folio); 2301 if (objcg && !obj_cgroup_may_zswap(objcg)) { 2302 memcg = get_mem_cgroup_from_objcg(objcg); 2303 if (shrink_memcg(memcg)) { 2304 mem_cgroup_put(memcg); 2305 goto put_objcg; 2306 } 2307 mem_cgroup_put(memcg); 2308 } 2309 2310 if (zswap_check_limits()) 2311 goto put_objcg; 2312 2313 if (objcg) { 2314 memcg = get_mem_cgroup_from_objcg(objcg); > 2315 if (memcg_list_lru_alloc(memcg, &zswap_list_lru, GFP_KERNEL)) { 2316 mem_cgroup_put(memcg); 2317 goto put_objcg; 2318 } 2319 mem_cgroup_put(memcg); 2320 } 2321 2322 /* 2323 * By default, set zswap error status in "errors" to "success" 2324 * for use in swap_writepage() when this returns. In case of 2325 * errors encountered in any sub-batch in which this folio's 2326 * pages are batch-compressed, a negative error number will 2327 * over-write this when zswap_batch_cleanup() is called. 2328 */ 2329 errors[i] = 0; 2330 ret = zswap_batch_comp_folio(folio, errors, i, objcg, &sub_batch, 2331 (i == folio_batch_count(batch) - 1)); 2332 2333 put_objcg: 2334 obj_cgroup_put(objcg); 2335 if (!ret && zswap_pool_reached_full) 2336 queue_work(shrink_wq, &zswap_shrink_work); 2337 } /* for batch folios */ 2338 2339 zswap_pool_put(pool); 2340 2341 check_old: 2342 for (i = 0; i < folio_batch_count(batch); ++i) 2343 if (errors[i]) 2344 zswap_delete_stored_entries(batch->folios[i]); 2345 } 2346 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
