Hi Andy, I love your patch! Yet something to improve: [auto build test ERROR on usb/usb-testing] [also build test ERROR on usb/usb-next usb/usb-linus linus/master v6.1-rc5 next-20221114] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Andy-Shevchenko/list-Introduce-list_count-to-count-existing-nodes/20221114-193023 base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing patch link: https://lore.kernel.org/r/20221114112842.38565-1-andriy.shevchenko%40linux.intel.com patch subject: [PATCH v1 1/4] list: Introduce list_count() to count existing nodes config: x86_64-rhel-8.3-func compiler: gcc-11 (Debian 11.3.0-8) 11.3.0 reproduce (this is a W=1 build): # https://github.com/intel-lab-lkp/linux/commit/124813c325e31e99580c2aaef85bb3943e55c36e git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Andy-Shevchenko/list-Introduce-list_count-to-count-existing-nodes/20221114-193023 git checkout 124813c325e31e99580c2aaef85bb3943e55c36e # save the config file mkdir build_dir && cp config build_dir/.config make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/gpu/drm/i915/ If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot All errors (new ones prefixed by >>): In file included from include/linux/mutex.h:15, from include/linux/seq_file.h:9, from include/drm/drm_print.h:31, from drivers/gpu/drm/i915/gt/intel_engine_cs.c:8: >> include/linux/list.h:663:2: error: expected identifier or '(' before '{' token 663 | ({ \ | ^ drivers/gpu/drm/i915/gt/intel_engine_cs.c:2007:22: note: in expansion of macro 'list_count' 2007 | static unsigned long list_count(struct list_head *list) | ^~~~~~~~~~ vim +663 include/linux/list.h 557 558 /** 559 * list_next_entry - get the next element in list 560 * @pos: the type * to cursor 561 * @member: the name of the list_head within the struct. 562 */ 563 #define list_next_entry(pos, member) \ 564 list_entry((pos)->member.next, typeof(*(pos)), member) 565 566 /** 567 * list_next_entry_circular - get the next element in list 568 * @pos: the type * to cursor. 569 * @head: the list head to take the element from. 570 * @member: the name of the list_head within the struct. 571 * 572 * Wraparound if pos is the last element (return the first element). 573 * Note, that list is expected to be not empty. 574 */ 575 #define list_next_entry_circular(pos, head, member) \ 576 (list_is_last(&(pos)->member, head) ? \ 577 list_first_entry(head, typeof(*(pos)), member) : list_next_entry(pos, member)) 578 579 /** 580 * list_prev_entry - get the prev element in list 581 * @pos: the type * to cursor 582 * @member: the name of the list_head within the struct. 583 */ 584 #define list_prev_entry(pos, member) \ 585 list_entry((pos)->member.prev, typeof(*(pos)), member) 586 587 /** 588 * list_prev_entry_circular - get the prev element in list 589 * @pos: the type * to cursor. 590 * @head: the list head to take the element from. 591 * @member: the name of the list_head within the struct. 592 * 593 * Wraparound if pos is the first element (return the last element). 594 * Note, that list is expected to be not empty. 595 */ 596 #define list_prev_entry_circular(pos, head, member) \ 597 (list_is_first(&(pos)->member, head) ? \ 598 list_last_entry(head, typeof(*(pos)), member) : list_prev_entry(pos, member)) 599 600 /** 601 * list_for_each - iterate over a list 602 * @pos: the &struct list_head to use as a loop cursor. 603 * @head: the head for your list. 604 */ 605 #define list_for_each(pos, head) \ 606 for (pos = (head)->next; !list_is_head(pos, (head)); pos = pos->next) 607 608 /** 609 * list_for_each_rcu - Iterate over a list in an RCU-safe fashion 610 * @pos: the &struct list_head to use as a loop cursor. 611 * @head: the head for your list. 612 */ 613 #define list_for_each_rcu(pos, head) \ 614 for (pos = rcu_dereference((head)->next); \ 615 !list_is_head(pos, (head)); \ 616 pos = rcu_dereference(pos->next)) 617 618 /** 619 * list_for_each_continue - continue iteration over a list 620 * @pos: the &struct list_head to use as a loop cursor. 621 * @head: the head for your list. 622 * 623 * Continue to iterate over a list, continuing after the current position. 624 */ 625 #define list_for_each_continue(pos, head) \ 626 for (pos = pos->next; !list_is_head(pos, (head)); pos = pos->next) 627 628 /** 629 * list_for_each_prev - iterate over a list backwards 630 * @pos: the &struct list_head to use as a loop cursor. 631 * @head: the head for your list. 632 */ 633 #define list_for_each_prev(pos, head) \ 634 for (pos = (head)->prev; !list_is_head(pos, (head)); pos = pos->prev) 635 636 /** 637 * list_for_each_safe - iterate over a list safe against removal of list entry 638 * @pos: the &struct list_head to use as a loop cursor. 639 * @n: another &struct list_head to use as temporary storage 640 * @head: the head for your list. 641 */ 642 #define list_for_each_safe(pos, n, head) \ 643 for (pos = (head)->next, n = pos->next; \ 644 !list_is_head(pos, (head)); \ 645 pos = n, n = pos->next) 646 647 /** 648 * list_for_each_prev_safe - iterate over a list backwards safe against removal of list entry 649 * @pos: the &struct list_head to use as a loop cursor. 650 * @n: another &struct list_head to use as temporary storage 651 * @head: the head for your list. 652 */ 653 #define list_for_each_prev_safe(pos, n, head) \ 654 for (pos = (head)->prev, n = pos->prev; \ 655 !list_is_head(pos, (head)); \ 656 pos = n, n = pos->prev) 657 658 /** 659 * list_count - count nodes in the list 660 * @head: the head for your list. 661 */ 662 #define list_count(head) \ > 663 ({ \ 664 struct list_head *__tmp; \ 665 size_t __i = 0; \ 666 list_for_each(__tmp, head) \ 667 __i++; \ 668 __i; \ 669 }) 670 -- 0-DAY CI Kernel Test Service https://01.org/lkp