Heiko Carstens <heiko.carst...@de.ibm.com> writes: > On Wed, Jan 06, 2016 at 11:20:55AM +0800, kernel test robot wrote: >> FYI, we noticed the below changes on >> >> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master >> commit 6cdb18ad98a49f7e9b95d538a0614cde827404b8 ("mm/vmstat: fix overflow in >> mod_zone_page_state()") >> >> >> ========================================================================================= >> compiler/cpufreq_governor/kconfig/rootfs/tbox_group/test/testcase: >> >> gcc-4.9/performance/x86_64-rhel/debian-x86_64-2015-02-07.cgz/ivb42/pread1/will-it-scale >> >> commit: >> cc28d6d80f6ab494b10f0e2ec949eacd610f66e3 >> 6cdb18ad98a49f7e9b95d538a0614cde827404b8 >> >> cc28d6d80f6ab494 6cdb18ad98a49f7e9b95d538a0 >> ---------------- -------------------------- >> %stddev %change %stddev >> \ | \ >> 2733943 . 0% -8.5% 2502129 . 0% will-it-scale.per_thread_ops >> 3410 . 0% -2.0% 3343 . 0% will-it-scale.time.system_time >> 340.08 . 0% +19.7% 406.99 . 0% will-it-scale.time.user_time >> 69882822 . 2% -24.3% 52926191 . 5% cpuidle.C1-IVT.time >> 340.08 . 0% +19.7% 406.99 . 0% time.user_time >> 491.25 . 6% -17.7% 404.25 . 7% >> numa-vmstat.node0.nr_alloc_batch >> 2799 . 20% -36.6% 1776 . 0% numa-vmstat.node0.nr_mapped >> 630.00 .140% +244.4% 2169 . 1% >> numa-vmstat.node1.nr_inactive_anon > > Hmm... this is odd. I did review all callers of mod_zone_page_state() and > couldn't find anything obvious that would go wrong after the int -> long > change. > > I also tried the "pread1_threads" test case from > https://github.com/antonblanchard/will-it-scale.git > > However the results seem to vary a lot after a reboot(!), at least on s390. > > So I'm not sure if this is really a regression.
Most part of the regression is restored for v4.4. But because the changes are like "V", it is hard to bisect. ========================================================================================= compiler/cpufreq_governor/kconfig/mode/nr_task/rootfs/tbox_group/test/testcase: gcc-4.9/performance/x86_64-rhel/thread/24/debian-x86_64-2015-02-07.cgz/ivb42/pread1/will-it-scale commit: cc28d6d80f6ab494b10f0e2ec949eacd610f66e3 6cdb18ad98a49f7e9b95d538a0614cde827404b8 v4.4 cc28d6d80f6ab494 6cdb18ad98a49f7e9b95d538a0 v4.4 ---------------- -------------------------- -------------------------- %stddev %change %stddev %change %stddev \ | \ | \ 3083436 ± 0% -9.6% 2788374 ± 0% -3.7% 2970130 ± 0% will-it-scale.per_thread_ops 6447 ± 0% -2.2% 6308 ± 0% -0.3% 6425 ± 0% will-it-scale.time.system_time 776.90 ± 0% +17.9% 915.71 ± 0% +2.9% 799.12 ± 0% will-it-scale.time.user_time 316177 ± 4% -4.6% 301616 ± 3% -10.3% 283563 ± 3% softirqs.RCU 776.90 ± 0% +17.9% 915.71 ± 0% +2.9% 799.12 ± 0% time.user_time 777.33 ± 7% +20.8% 938.67 ± 7% +7.5% 836.00 ± 8% slabinfo.blkdev_requests.active_objs 777.33 ± 7% +20.8% 938.67 ± 7% +7.5% 836.00 ± 8% slabinfo.blkdev_requests.num_objs 74313962 ± 44% -16.5% 62053062 ± 41% -49.9% 37246967 ± 8% cpuidle.C1-IVT.time 43381614 ± 79% +24.4% 53966568 ±111% +123.9% 97135791 ± 33% cpuidle.C1E-IVT.time 97.67 ± 36% +95.2% 190.67 ± 63% +122.5% 217.33 ± 41% cpuidle.C3-IVT.usage 3679437 ± 69% -100.0% 0.00 ± -1% -100.0% 0.00 ± -1% latency_stats.avg.nfs_wait_on_request.nfs_updatepage.nfs_write_end.generic_perform_write.__generic_file_write_iter.generic_file_write_iter.nfs_file_write.__vfs_write.vfs_write.SyS_write.entry_SYSCALL_64_fastpath 5177475 ± 82% -100.0% 0.00 ± -1% -100.0% 0.00 ± -1% latency_stats.max.nfs_wait_on_request.nfs_updatepage.nfs_write_end.generic_perform_write.__generic_file_write_iter.generic_file_write_iter.nfs_file_write.__vfs_write.vfs_write.SyS_write.entry_SYSCALL_64_fastpath 11726393 ±112% -100.0% 0.00 ± -1% -100.0% 0.00 ± -1% latency_stats.sum.nfs_wait_on_request.nfs_updatepage.nfs_write_end.generic_perform_write.__generic_file_write_iter.generic_file_write_iter.nfs_file_write.__vfs_write.vfs_write.SyS_write.entry_SYSCALL_64_fastpath 178.07 ± 0% -1.3% 175.79 ± 0% -0.8% 176.62 ± 0% turbostat.CorWatt 0.20 ± 2% -16.9% 0.16 ± 18% -11.9% 0.17 ± 17% turbostat.Pkg%pc6 207.38 ± 0% -1.1% 205.13 ± 0% -0.7% 205.99 ± 0% turbostat.PkgWatt 6889 ± 33% -49.2% 3497 ± 86% -19.4% 5552 ± 27% numa-vmstat.node0.nr_active_anon 483.33 ± 29% -32.3% 327.00 ± 48% +0.1% 483.67 ± 29% numa-vmstat.node0.nr_page_table_pages 27536 ± 96% +10.9% 30535 ± 78% +148.5% 68418 ± 2% numa-vmstat.node0.numa_other 214.00 ± 11% +18.1% 252.67 ± 4% +2.8% 220.00 ± 9% numa-vmstat.node1.nr_kernel_stack 370.67 ± 38% +42.0% 526.33 ± 30% -0.2% 370.00 ± 39% numa-vmstat.node1.nr_page_table_pages 61177 ± 43% -5.2% 57976 ± 41% -66.3% 20644 ± 10% numa-vmstat.node1.numa_other 78172 ± 13% -16.1% 65573 ± 18% -5.8% 73626 ± 9% numa-meminfo.node0.Active 27560 ± 33% -49.2% 14006 ± 86% -19.4% 22203 ± 27% numa-meminfo.node0.Active(anon) 3891 ± 58% -38.1% 2407 ±100% -58.8% 1604 ±110% numa-meminfo.node0.AnonHugePages 1934 ± 29% -32.3% 1309 ± 48% +0.1% 1936 ± 29% numa-meminfo.node0.PageTables 63139 ± 17% +19.8% 75670 ± 16% +6.0% 66937 ± 10% numa-meminfo.node1.Active 3432 ± 11% +18.0% 4049 ± 4% +2.8% 3527 ± 9% numa-meminfo.node1.KernelStack 1483 ± 38% +42.0% 2106 ± 30% -0.2% 1481 ± 39% numa-meminfo.node1.PageTables 1.47 ± 1% -11.8% 1.30 ± 2% -7.0% 1.37 ± 3% perf-profile.cycles-pp.___might_sleep.__might_sleep.find_lock_entry.shmem_getpage_gfp.shmem_file_read_iter 2.00 ± 2% -11.3% 1.78 ± 2% -7.2% 1.86 ± 2% perf-profile.cycles-pp.__might_sleep.find_lock_entry.shmem_getpage_gfp.shmem_file_read_iter.__vfs_read 2.30 ± 4% +33.6% 3.07 ± 0% -1.9% 2.26 ± 1% perf-profile.cycles-pp.atime_needs_update.touch_atime.shmem_file_read_iter.__vfs_read.vfs_read 1.05 ± 1% -27.7% 0.76 ± 1% -8.0% 0.96 ± 0% perf-profile.cycles-pp.current_fs_time.atime_needs_update.touch_atime.shmem_file_read_iter.__vfs_read 2.21 ± 3% -11.9% 1.94 ± 2% -9.4% 2.00 ± 0% perf-profile.cycles-pp.fput.entry_SYSCALL_64_fastpath 0.78 ± 2% +38.5% 1.08 ± 2% +23.1% 0.96 ± 3% perf-profile.cycles-pp.fsnotify.vfs_read.sys_pread64.entry_SYSCALL_64_fastpath 2.87 ± 7% +42.6% 4.09 ± 1% -0.3% 2.86 ± 2% perf-profile.cycles-pp.touch_atime.shmem_file_read_iter.__vfs_read.vfs_read.sys_pread64 6.68 ± 2% -7.3% 6.19 ± 1% -6.7% 6.23 ± 1% perf-profile.cycles-pp.unlock_page.shmem_file_read_iter.__vfs_read.vfs_read.sys_pread64 Best Regards, Huang, Ying