aboutsummaryrefslogtreecommitdiff
path: root/drivers
diff options
context:
space:
mode:
authorWaiman Long <longman@redhat.com>2019-05-24 15:42:22 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2019-05-24 14:17:18 -0700
commit51816e9e113934281b44f1a352852ef7631e75ea (patch)
tree2f2d6cc2f33a22e3a0603d844396bf3f5d5b6592 /drivers
parent0a72ef89901409847036664c23ba6eee7cf08e0e (diff)
locking/lock_events: Use this_cpu_add() when necessary
The kernel test robot has reported that the use of __this_cpu_add() causes bug messages like: BUG: using __this_cpu_add() in preemptible [00000000] code: ... Given the imprecise nature of the count and the possibility of resetting the count and doing the measurement again, this is not really a big problem to use the unprotected __this_cpu_*() functions. To make the preemption checking code happy, the this_cpu_*() functions will be used if CONFIG_DEBUG_PREEMPT is defined. The imprecise nature of the locking counts are also documented with the suggestion that we should run the measurement a few times with the counts reset in between to get a better picture of what is going on under the hood. Fixes: a8654596f0371 ("locking/rwsem: Enable lock event counting") Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers')
0 files changed, 0 insertions, 0 deletions