Hi Johannes, I love your patch! Yet something to improve: [auto build test ERROR on vfs/for-next] [also build test ERROR on linux/master linus/master v5.6-rc1 next-20200213] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/Johannes-Weiner/vfs-keep-inodes-with-page-cache-off-the-inode-shrinker-LRU/20200214-083756 base: https://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git for-next config: m68k-allmodconfig (attached as .config) compiler: m68k-linux-gcc (GCC) 7.5.0 reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # save the attached .config to linux build tree GCC_VERSION=7.5.0 make.cross ARCH=m68k If you fix the issue, kindly add following tag Reported-by: kbuild test robot <lkp@xxxxxxxxx> All errors (new ones prefixed by >>): fs/dax.c: In function 'grab_mapping_entry': >> fs/dax.c:556:28: error: 'struct address_space' has no member named 'inode' inode_pages_clear(mapping->inode); ^~ fs/dax.c:558:26: error: 'struct address_space' has no member named 'inode' inode_pages_set(mapping->inode); ^~ vim +556 fs/dax.c 446 447 /* 448 * Find page cache entry at given index. If it is a DAX entry, return it 449 * with the entry locked. If the page cache doesn't contain an entry at 450 * that index, add a locked empty entry. 451 * 452 * When requesting an entry with size DAX_PMD, grab_mapping_entry() will 453 * either return that locked entry or will return VM_FAULT_FALLBACK. 454 * This will happen if there are any PTE entries within the PMD range 455 * that we are requesting. 456 * 457 * We always favor PTE entries over PMD entries. There isn't a flow where we 458 * evict PTE entries in order to 'upgrade' them to a PMD entry. A PMD 459 * insertion will fail if it finds any PTE entries already in the tree, and a 460 * PTE insertion will cause an existing PMD entry to be unmapped and 461 * downgraded to PTE entries. This happens for both PMD zero pages as 462 * well as PMD empty entries. 463 * 464 * The exception to this downgrade path is for PMD entries that have 465 * real storage backing them. We will leave these real PMD entries in 466 * the tree, and PTE writes will simply dirty the entire PMD entry. 467 * 468 * Note: Unlike filemap_fault() we don't honor FAULT_FLAG_RETRY flags. For 469 * persistent memory the benefit is doubtful. We can add that later if we can 470 * show it helps. 471 * 472 * On error, this function does not return an ERR_PTR. Instead it returns 473 * a VM_FAULT code, encoded as an xarray internal entry. The ERR_PTR values 474 * overlap with xarray value entries. 475 */ 476 static void *grab_mapping_entry(struct xa_state *xas, 477 struct address_space *mapping, unsigned int order) 478 { 479 unsigned long index = xas->xa_index; 480 bool pmd_downgrade = false; /* splitting PMD entry into PTE entries? */ 481 int populated; 482 void *entry; 483 484 retry: 485 populated = 0; 486 xas_lock_irq(xas); 487 entry = get_unlocked_entry(xas, order); 488 489 if (entry) { 490 if (dax_is_conflict(entry)) 491 goto fallback; 492 if (!xa_is_value(entry)) { 493 xas_set_err(xas, EIO); 494 goto out_unlock; 495 } 496 497 if (order == 0) { 498 if (dax_is_pmd_entry(entry) && 499 (dax_is_zero_entry(entry) || 500 dax_is_empty_entry(entry))) { 501 pmd_downgrade = true; 502 } 503 } 504 } 505 506 if (pmd_downgrade) { 507 /* 508 * Make sure 'entry' remains valid while we drop 509 * the i_pages lock. 510 */ 511 dax_lock_entry(xas, entry); 512 513 /* 514 * Besides huge zero pages the only other thing that gets 515 * downgraded are empty entries which don't need to be 516 * unmapped. 517 */ 518 if (dax_is_zero_entry(entry)) { 519 xas_unlock_irq(xas); 520 unmap_mapping_pages(mapping, 521 xas->xa_index & ~PG_PMD_COLOUR, 522 PG_PMD_NR, false); 523 xas_reset(xas); 524 xas_lock_irq(xas); 525 } 526 527 dax_disassociate_entry(entry, mapping, false); 528 xas_store(xas, NULL); /* undo the PMD join */ 529 dax_wake_entry(xas, entry, true); 530 mapping->nrexceptional--; 531 if (mapping_empty(mapping)) 532 populated = -1; 533 entry = NULL; 534 xas_set(xas, index); 535 } 536 537 if (entry) { 538 dax_lock_entry(xas, entry); 539 } else { 540 unsigned long flags = DAX_EMPTY; 541 542 if (order > 0) 543 flags |= DAX_PMD; 544 entry = dax_make_entry(pfn_to_pfn_t(0), flags); 545 dax_lock_entry(xas, entry); 546 if (xas_error(xas)) 547 goto out_unlock; 548 if (mapping_empty(mapping)) 549 populated++; 550 mapping->nrexceptional++; 551 } 552 553 out_unlock: 554 xas_unlock_irq(xas); 555 if (populated == -1) > 556 inode_pages_clear(mapping->inode); 557 else if (populated == 1) 558 inode_pages_set(mapping->inode); 559 if (xas_nomem(xas, mapping_gfp_mask(mapping) & ~__GFP_HIGHMEM)) 560 goto retry; 561 if (xas->xa_node == XA_ERROR(-ENOMEM)) 562 return xa_mk_internal(VM_FAULT_OOM); 563 if (xas_error(xas)) 564 return xa_mk_internal(VM_FAULT_SIGBUS); 565 return entry; 566 fallback: 567 xas_unlock_irq(xas); 568 return xa_mk_internal(VM_FAULT_FALLBACK); 569 } 570 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx
Attachment:
.config.gz
Description: application/gzip
