[linus:master] [x86/signal] 9da9f342a8: stress-ng.timer.ops_per_sec 2.8% improvement

[linus:master] [x86/signal] 9da9f342a8: stress-ng.timer.ops_per_sec 2.8% improvement

[kernel test robot]

Hello,

kernel test robot noticed a 2.8% improvement of stress-ng.timer.ops_per_sec on:


commit: 9da9f342a897a2d43ad947d4073b1912800ab436 ("x86/signal: Use scoped user access in the sigreturn system calls") https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master

testcase: stress-ng
config: x86_64-rhel-9.4
compiler: gcc-14
test machine: 192 threads 2 sockets Intel(R) Xeon(R) 6740E  CPU @ 2.4GHz (Sierra Forest) with 256G memory
parameters:

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


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


The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20261108/202611080951.256d230a-lkp@intel.com

=========================================================================================
compiler/cpufreq_governor/kconfig/nr_threads/rootfs/tbox_group/test/testcase/testtime:
  gcc-14/performance/x86_64-rhel-9.4/100%/debian-13-x86_64-20250902.cgz/lkp-srf-2sp3/timer/stress-ng/60s

commit: 
  2806617c9c ("x86/entry: Use get_user() for the fast 32-bit syscall EBP fetch")
  9da9f342a8 ("x86/signal: Use scoped user access in the sigreturn system calls")

2806617c9c02fe16 9da9f342a897a2d43ad947d4073
---------------- --------------------------- 
         %stddev     %change         %stddev
             \          |                \  
      9031            +1.9%       9207        stress-ng.time.system_time
      1344           -11.8%       1184 ±  2%  stress-ng.time.user_time
 5.442e+09            +2.8%  5.593e+09        stress-ng.timer.ops
  90751049            +2.8%   93261655        stress-ng.timer.ops_per_sec


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