[linus:master] [x86] 2865baf540: stress-ng.access.access_calls_per_sec 6.8% improvement

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

Hello,

kernel test robot noticed a 6.8% improvement of stress-ng.access.access_calls_per_sec on:


commit: 2865baf54077aa98fcdb478cefe6a42c417b9374 ("x86: support user address masking instead of non-speculative conditional")
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master

testcase: stress-ng
config: x86_64-rhel-8.3
compiler: gcc-12
test machine: 64 threads 2 sockets Intel(R) Xeon(R) Gold 6346 CPU @ 3.10GHz (Ice Lake) with 256G memory
parameters:

	nr_threads: 100%
	disk: 1HDD
	testtime: 60s
	fs: btrfs
	test: access
	cpufreq_governor: performance






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


The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20241016/202410161557.5b87225e-oliver.sang@intel.com

=========================================================================================
compiler/cpufreq_governor/disk/fs/kconfig/nr_threads/rootfs/tbox_group/test/testcase/testtime:
  gcc-12/performance/1HDD/btrfs/x86_64-rhel-8.3/100%/debian-12-x86_64-20240206.cgz/lkp-icl-2sp8/access/stress-ng/60s

commit: 
  v6.10
  2865baf540 ("x86: support user address masking instead of non-speculative conditional")

           v6.10 2865baf54077aa98fcdb478cefe 
---------------- --------------------------- 
         %stddev     %change         %stddev
             \          |                \  
      1008 ± 35%     -45.4%     550.53 ± 74%  numa-meminfo.node0.Inactive(file)
    100.41 ± 55%     -63.1%      37.01 ± 70%  perf-sched.wait_and_delay.max.ms.__cond_resched.generic_perform_write.shmem_file_write_iter.vfs_write.ksys_write
   3373715            +6.8%    3603928        stress-ng.access.access_calls_per_sec
    252.58 ± 35%     -45.5%     137.68 ± 74%  numa-vmstat.node0.nr_inactive_file
    252.58 ± 35%     -45.5%     137.68 ± 74%  numa-vmstat.node0.nr_zone_inactive_file
      4.08            +3.5%       4.23        perf-stat.i.cpi
      4.10            +3.2%       4.24        perf-stat.overall.cpi
      0.24            -3.1%       0.24        perf-stat.overall.ipc
 3.326e+12            -3.2%   3.22e+12        perf-stat.total.instructions
      2.33 ±  5%      -0.2        2.10 ±  4%  perf-profile.calltrace.cycles-pp.syscall
      1.85 ±  5%      -0.2        1.63 ±  4%  perf-profile.calltrace.cycles-pp.do_syscall_64.entry_SYSCALL_64_after_hwframe.faccessat
      1.86 ±  5%      -0.2        1.65 ±  4%  perf-profile.calltrace.cycles-pp.entry_SYSCALL_64_after_hwframe.syscall
      1.76 ±  5%      -0.2        1.55 ±  4%  perf-profile.calltrace.cycles-pp.do_faccessat.do_syscall_64.entry_SYSCALL_64_after_hwframe.faccessat
      1.83 ±  5%      -0.2        1.62 ±  4%  perf-profile.calltrace.cycles-pp.do_syscall_64.entry_SYSCALL_64_after_hwframe.syscall
      1.87 ±  5%      -0.2        1.66 ±  4%  perf-profile.calltrace.cycles-pp.entry_SYSCALL_64_after_hwframe.faccessat
      1.73 ±  5%      -0.2        1.52 ±  4%  perf-profile.calltrace.cycles-pp.do_faccessat.do_syscall_64.entry_SYSCALL_64_after_hwframe.syscall
      1.48 ±  5%      -0.2        1.27 ±  4%  perf-profile.calltrace.cycles-pp.user_path_at_empty.do_faccessat.do_syscall_64.entry_SYSCALL_64_after_hwframe.syscall
      1.49 ±  5%      -0.2        1.29 ±  4%  perf-profile.calltrace.cycles-pp.user_path_at_empty.do_faccessat.do_syscall_64.entry_SYSCALL_64_after_hwframe.faccessat
      2.19 ±  2%      -0.2        2.02 ±  3%  perf-profile.calltrace.cycles-pp.access
      1.84 ±  2%      -0.2        1.67 ±  3%  perf-profile.calltrace.cycles-pp.do_syscall_64.entry_SYSCALL_64_after_hwframe.access
      1.86 ±  2%      -0.2        1.69 ±  3%  perf-profile.calltrace.cycles-pp.entry_SYSCALL_64_after_hwframe.access
      1.76 ±  2%      -0.2        1.59 ±  3%  perf-profile.calltrace.cycles-pp.do_faccessat.do_syscall_64.entry_SYSCALL_64_after_hwframe.access
      1.40 ±  2%      -0.2        1.24 ±  3%  perf-profile.calltrace.cycles-pp.user_path_at_empty.do_faccessat.do_syscall_64.entry_SYSCALL_64_after_hwframe.access
      4.91 ±  4%      -0.6        4.28 ±  3%  perf-profile.children.cycles-pp.user_path_at_empty
      5.28 ±  4%      -0.6        4.70 ±  3%  perf-profile.children.cycles-pp.do_faccessat
      1.39 ±  4%      -0.5        0.84 ±  3%  perf-profile.children.cycles-pp.getname_flags
      0.95 ±  4%      -0.5        0.41 ±  3%  perf-profile.children.cycles-pp.strncpy_from_user
      2.41 ±  5%      -0.2        2.19 ±  4%  perf-profile.children.cycles-pp.syscall
      2.25 ±  2%      -0.2        2.08 ±  3%  perf-profile.children.cycles-pp.access
      0.12 ±  6%      -0.0        0.09 ±  5%  perf-profile.children.cycles-pp.btrfs_init_metadata_block_rsv
      0.08 ±  8%      -0.0        0.05 ±  8%  perf-profile.children.cycles-pp.btrfs_find_space_info
      0.10 ±  4%      -0.0        0.08 ±  5%  perf-profile.children.cycles-pp.fill_stack_inode_item
      0.48 ±  3%      -0.1        0.40 ±  3%  perf-profile.self.cycles-pp.strncpy_from_user
      0.08 ±  8%      -0.0        0.05 ±  7%  perf-profile.self.cycles-pp.btrfs_find_space_info




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