Hi Jan, https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Jan-Kara/ext4-Fix-performance-regression-with-mballoc/20220907-000945 base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 53e99dcff61e1523ec1c3628b2d564ba15d32eb7 config: m68k-randconfig-m041-20220906 (https://download.01.org/0day-ci/archive/20220907/202209071206.u1iHKVzB-lkp@xxxxxxxxx/config) compiler: m68k-linux-gcc (GCC) 12.1.0 If you fix the issue, kindly add following tag where applicable Reported-by: kernel test robot <lkp@xxxxxxxxx> Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> New smatch warnings: fs/ext4/mballoc.c:945 ext4_mb_choose_next_group_cr1() error: uninitialized symbol 'grp'. vim +/grp +945 fs/ext4/mballoc.c 196e402adf2e4c Harshad Shirwadkar 2021-04-01 909 static void ext4_mb_choose_next_group_cr1(struct ext4_allocation_context *ac, 196e402adf2e4c Harshad Shirwadkar 2021-04-01 910 int *new_cr, ext4_group_t *group, ext4_group_t ngroups) 196e402adf2e4c Harshad Shirwadkar 2021-04-01 911 { 196e402adf2e4c Harshad Shirwadkar 2021-04-01 912 struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb); 31b571b608cf66 Jan Kara 2022-09-06 913 struct ext4_group_info *grp, *iter; 31b571b608cf66 Jan Kara 2022-09-06 914 int i; 196e402adf2e4c Harshad Shirwadkar 2021-04-01 915 196e402adf2e4c Harshad Shirwadkar 2021-04-01 916 if (unlikely(ac->ac_flags & EXT4_MB_CR1_OPTIMIZED)) { 196e402adf2e4c Harshad Shirwadkar 2021-04-01 917 if (sbi->s_mb_stats) 196e402adf2e4c Harshad Shirwadkar 2021-04-01 918 atomic_inc(&sbi->s_bal_cr1_bad_suggestions); 31b571b608cf66 Jan Kara 2022-09-06 919 } 31b571b608cf66 Jan Kara 2022-09-06 920 31b571b608cf66 Jan Kara 2022-09-06 921 for (i = mb_avg_fragment_size_order(ac->ac_sb, ac->ac_g_ex.fe_len); 31b571b608cf66 Jan Kara 2022-09-06 922 i < MB_NUM_ORDERS(ac->ac_sb); i++) { 31b571b608cf66 Jan Kara 2022-09-06 923 if (list_empty(&sbi->s_mb_avg_fragment_size[i])) 31b571b608cf66 Jan Kara 2022-09-06 924 continue; 31b571b608cf66 Jan Kara 2022-09-06 925 read_lock(&sbi->s_mb_avg_fragment_size_locks[i]); 31b571b608cf66 Jan Kara 2022-09-06 926 if (list_empty(&sbi->s_mb_avg_fragment_size[i])) { 31b571b608cf66 Jan Kara 2022-09-06 927 read_unlock(&sbi->s_mb_largest_free_orders_locks[i]); 31b571b608cf66 Jan Kara 2022-09-06 928 continue; Smatch worries that we can hit these two continues on every iteration. Why not just initialize "grp = NULL;" at the start of the function? 31b571b608cf66 Jan Kara 2022-09-06 929 } 31b571b608cf66 Jan Kara 2022-09-06 930 grp = NULL; 31b571b608cf66 Jan Kara 2022-09-06 931 list_for_each_entry(iter, &sbi->s_mb_avg_fragment_size[i], 31b571b608cf66 Jan Kara 2022-09-06 932 bb_avg_fragment_size_node) { 196e402adf2e4c Harshad Shirwadkar 2021-04-01 933 if (sbi->s_mb_stats) 196e402adf2e4c Harshad Shirwadkar 2021-04-01 934 atomic64_inc(&sbi->s_bal_cX_groups_considered[1]); 31b571b608cf66 Jan Kara 2022-09-06 935 if (likely(ext4_mb_good_group(ac, iter->bb_group, 1))) { 31b571b608cf66 Jan Kara 2022-09-06 936 grp = iter; 196e402adf2e4c Harshad Shirwadkar 2021-04-01 937 break; 196e402adf2e4c Harshad Shirwadkar 2021-04-01 938 } 196e402adf2e4c Harshad Shirwadkar 2021-04-01 939 } 31b571b608cf66 Jan Kara 2022-09-06 940 read_unlock(&sbi->s_mb_avg_fragment_size_locks[i]); 31b571b608cf66 Jan Kara 2022-09-06 941 if (grp) 31b571b608cf66 Jan Kara 2022-09-06 942 break; 196e402adf2e4c Harshad Shirwadkar 2021-04-01 943 } 196e402adf2e4c Harshad Shirwadkar 2021-04-01 944 31b571b608cf66 Jan Kara 2022-09-06 @945 if (grp) { 196e402adf2e4c Harshad Shirwadkar 2021-04-01 946 *group = grp->bb_group; 196e402adf2e4c Harshad Shirwadkar 2021-04-01 947 ac->ac_flags |= EXT4_MB_CR1_OPTIMIZED; 196e402adf2e4c Harshad Shirwadkar 2021-04-01 948 } else { 196e402adf2e4c Harshad Shirwadkar 2021-04-01 949 *new_cr = 2; 196e402adf2e4c Harshad Shirwadkar 2021-04-01 950 } 196e402adf2e4c Harshad Shirwadkar 2021-04-01 951 } -- 0-DAY CI Kernel Test Service https://01.org/lkp
