5:23 a.m.
Hi Nicholas,
I love your patch! Yet something to improve:
[auto build test ERROR on powerpc/next]
[also build test ERROR on v5.10 next-20201217]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url:
https://github.com/0day-ci/linux/commits/Nicholas-Piggin/powerpc-64s-TLB-...
base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-randconfig-m031-20201217 (attached as .config)
compiler: powerpc64le-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O
~/bin/make.cross
chmod +x ~/bin/make.cross
#
https://github.com/0day-ci/linux/commit/5bd02bea3da4e21fa00729e7687fc93a5...
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review
Nicholas-Piggin/powerpc-64s-TLB-flushing-improvements/20201217-220230
git checkout 5bd02bea3da4e21fa00729e7687fc93a5c653e2b
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=powerpc
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp(a)intel.com>
All errors (new ones prefixed by >>):
> arch/powerpc/mm/book3s64/radix_tlb.c:646:6: error: no previous
prototype for 'exit_lazy_flush_tlb' [-Werror=missing-prototypes]
646 |
void exit_lazy_flush_tlb(struct mm_struct *mm, bool always_flush)
| ^~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
vim +/exit_lazy_flush_tlb +646 arch/powerpc/mm/book3s64/radix_tlb.c
641
642 /*
643 * If always_flush is true, then flush even if this CPU can't be removed
644 * from mm_cpumask.
645 */
646 void exit_lazy_flush_tlb(struct mm_struct *mm, bool always_flush)
647 {
648 unsigned long pid = mm->context.id;
649 int cpu = smp_processor_id();
650
651 /*
652 * A kthread could have done a mmget_not_zero() after the flushing CPU
653 * checked mm_cpumask, and be in the process of kthread_use_mm when
654 * interrupted here. In that case, current->mm will be set to mm,
655 * because kthread_use_mm() setting ->mm and switching to the mm is
656 * done with interrupts off.
657 */
658 if (current->mm == mm)
659 goto out;
660
661 if (current->active_mm == mm) {
662 WARN_ON_ONCE(current->mm != NULL);
663 /* Is a kernel thread and is using mm as the lazy tlb */
664 mmgrab(&init_mm);
665 current->active_mm = &init_mm;
666 switch_mm_irqs_off(mm, &init_mm, current);
667 mmdrop(mm);
668 }
669
670 /*
671 * This IPI may be initiated from any source including those not
672 * running the mm, so there may be a racing IPI that comes after
673 * this one which finds the cpumask already clear. Check and avoid
674 * underflowing the active_cpus count in that case. The race should
675 * not otherwise be a problem, but the TLB must be flushed because
676 * that's what the caller expects.
677 */
678 if (cpumask_test_cpu(cpu, mm_cpumask(mm))) {
679 atomic_dec(&mm->context.active_cpus);
680 cpumask_clear_cpu(cpu, mm_cpumask(mm));
681 always_flush = true;
682 }
683
684 out:
685 if (always_flush)
686 _tlbiel_pid(pid, RIC_FLUSH_ALL);
687 }
688
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org