[linux-next:master] [mm] 7b6218ae12: stress-ng.forkheavy.ops_per_sec 5.0% improvement

[kernel test robot <oliver.sang@intel.com>]

Hello,

kernel test robot noticed a 5.0% improvement of stress-ng.forkheavy.ops_per_sec on:


commit: 7b6218ae1253491d56f21f4b1f3609f3dd873600 ("mm: move per-vma lock into vm_area_struct")
https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git master


testcase: stress-ng
config: x86_64-rhel-9.4
compiler: gcc-12
test machine: 192 threads 2 sockets Intel(R) Xeon(R) Platinum 8468V  CPU @ 2.4GHz (Sapphire Rapids) with 384G memory
parameters:

	nr_threads: 100%
	testtime: 60s
	test: forkheavy
	cpufreq_governor: performance



Details are as below:
-------------------------------------------------------------------------------------------------->


The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20250331/202503311656.e3596aaf-lkp@intel.com

=========================================================================================
compiler/cpufreq_governor/kconfig/nr_threads/rootfs/tbox_group/test/testcase/testtime:
  gcc-12/performance/x86_64-rhel-9.4/100%/debian-12-x86_64-20240206.cgz/igk-spr-2sp1/forkheavy/stress-ng/60s

commit: 
  b2ae5fccb8 ("mm: introduce vma_start_read_locked{_nested} helpers")
  7b6218ae12 ("mm: move per-vma lock into vm_area_struct")

b2ae5fccb8c0ec21 7b6218ae1253491d56f21f4b1f3 
---------------- --------------------------- 
         %stddev     %change         %stddev
             \          |                \  
    382800 ±  4%     +10.2%     421797 ±  5%  numa-meminfo.node1.AnonHugePages
     32850            +5.0%      34492        stress-ng.forkheavy.ops
    493.66            +5.0%     518.50        stress-ng.forkheavy.ops_per_sec
     40.74 ± 30%     +68.2%      68.53 ± 23%  sched_debug.cfs_rq:/.removed.runnable_avg.stddev
     73.19 ± 42%     +52.2%     111.39 ± 16%  sched_debug.cfs_rq:/.util_est.avg
    222.12 ± 29%     +34.4%     298.62 ± 10%  sched_debug.cfs_rq:/.util_est.stddev
      4555 ± 10%     -45.3%       2491 ± 27%  perf-c2c.DRAM.local
     11750 ±  4%     -22.7%       9082 ± 22%  perf-c2c.HITM.local
      2592 ±  6%     -45.4%       1414 ± 23%  perf-c2c.HITM.remote
     14342 ±  4%     -26.8%      10497 ± 22%  perf-c2c.HITM.total
  41336771            -4.4%   39526485        proc-vmstat.numa_hit
  41134683            -4.4%   39326465        proc-vmstat.numa_local
  71479761            +1.8%   72742225        proc-vmstat.pgalloc_normal
   3480841            +2.4%    3564757        proc-vmstat.pgfault
  71044889            +1.7%   72274310        proc-vmstat.pgfree
      1.47 ± 86%     -73.5%       0.39 ±138%  perf-sched.sch_delay.avg.ms.__cond_resched.do_ftruncate.do_sys_ftruncate.do_syscall_64.entry_SYSCALL_64_after_hwframe
      0.33 ±108%    +205.7%       1.00 ± 83%  perf-sched.sch_delay.avg.ms.__cond_resched.down_write.do_mq_open.__x64_sys_mq_open.do_syscall_64
      0.77 ± 25%     +43.6%       1.10 ± 21%  perf-sched.sch_delay.avg.ms.__cond_resched.dput.vfs_tmpfile.path_openat.do_filp_open
      0.16 ± 17%     +44.7%       0.23 ± 26%  perf-sched.sch_delay.avg.ms.do_wait.kernel_wait4.do_syscall_64.entry_SYSCALL_64_after_hwframe
      0.58 ± 85%     -85.8%       0.08 ±130%  perf-sched.sch_delay.avg.ms.irqentry_exit_to_user_mode.asm_sysvec_reschedule_ipi.[unknown]
      3.92 ± 72%     -80.6%       0.76 ±198%  perf-sched.sch_delay.max.ms.irqentry_exit_to_user_mode.asm_sysvec_reschedule_ipi.[unknown]
      6.96 ± 55%    +113.7%      14.88 ± 28%  perf-sched.sch_delay.max.ms.smpboot_thread_fn.kthread.ret_from_fork.ret_from_fork_asm
     62.68 ± 72%    +129.9%     144.11 ±  9%  perf-sched.wait_and_delay.avg.ms.__cond_resched.smpboot_thread_fn.kthread.ret_from_fork.ret_from_fork_asm
    334.97 ± 57%     -66.4%     112.42 ± 70%  perf-sched.wait_and_delay.avg.ms.do_nanosleep.hrtimer_nanosleep.common_nsleep.__x64_sys_clock_nanosleep
     82.80 ± 23%     +73.9%     143.96 ±  9%  perf-sched.wait_time.avg.ms.__cond_resched.smpboot_thread_fn.kthread.ret_from_fork.ret_from_fork_asm
      2.15 ± 43%     -72.2%       0.60 ± 94%  perf-sched.wait_time.avg.ms.__cond_resched.unmap_vmas.unmap_region.__mmap_new_vma.__mmap_region
     68.44 ±135%    +288.8%     266.12 ±121%  perf-sched.wait_time.max.ms.__cond_resched.ww_mutex_lock.drm_gem_vunmap_unlocked.drm_gem_fb_vunmap.drm_atomic_helper_commit_planes
     15.31            +8.9%      16.67 ±  2%  perf-stat.i.MPKI
 1.684e+10            -3.9%  1.618e+10        perf-stat.i.branch-instructions
  75533943            -4.7%   72015903        perf-stat.i.branch-misses
      6.71            +5.6%       7.09        perf-stat.i.cpi
  8.19e+10            -5.7%  7.726e+10        perf-stat.i.instructions
      0.16            -4.9%       0.15        perf-stat.i.ipc
     16.72            +7.0%      17.90        perf-stat.overall.MPKI
      6.53            +6.2%       6.94        perf-stat.overall.cpi
      0.15            -5.9%       0.14        perf-stat.overall.ipc
  1.66e+10            -4.2%   1.59e+10        perf-stat.ps.branch-instructions
  73765712            -5.4%   69811938        perf-stat.ps.branch-misses
 8.092e+10            -5.9%  7.612e+10        perf-stat.ps.instructions
  5.53e+12            -5.5%  5.227e+12        perf-stat.total.instructions




Disclaimer:
Results have been estimated based on internal Intel analysis and are provided
for informational purposes only. Any difference in system hardware or software
design or configuration may affect actual performance.


-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki