diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2023-03-25 12:57:34 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2023-03-25 12:57:34 -0700 |
| commit | f768b35a2371ccf85255f608444d234062a1b5c9 (patch) | |
| tree | a22500f2422baceb3aa07ec46ee72f221c7f49a1 /include/linux/cpumask.h | |
| parent | d704426300f2e95275267a387ffc3b8e5f4ae8b7 (diff) | |
| parent | e9b60c7f97130795c7aa81a649ae4b93a172a277 (diff) | |
Merge tag 'xfs-6.3-fixes-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs percpu counter fixes from Darrick Wong:
"We discovered a filesystem summary counter corruption problem that was
traced to cpu hot-remove racing with the call to percpu_counter_sum
that sets the free block count in the superblock when writing it to
disk. The root cause is that percpu_counter_sum doesn't cull from
dying cpus and hence misses those counter values if the cpu shutdown
hooks have not yet run to merge the values.
I'm hoping this is a fairly painless fix to the problem, since the
dying cpu mask should generally be empty. It's been in for-next for a
week without any complaints from the bots.
- Fix a race in the percpu counters summation code where the
summation failed to add in the values for any CPUs that were dying
but not yet dead. This fixes some minor discrepancies and incorrect
assertions when running generic/650"
* tag 'xfs-6.3-fixes-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
pcpcntr: remove percpu_counter_sum_all()
fork: remove use of percpu_counter_sum_all
pcpcntrs: fix dying cpu summation race
cpumask: introduce for_each_cpu_or
Diffstat (limited to 'include/linux/cpumask.h')
| -rw-r--r-- | include/linux/cpumask.h | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h index d4901ca8883c..ca736b05ec7b 100644 --- a/include/linux/cpumask.h +++ b/include/linux/cpumask.h @@ -351,6 +351,23 @@ unsigned int __pure cpumask_next_wrap(int n, const struct cpumask *mask, int sta for_each_andnot_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), small_cpumask_bits) /** + * for_each_cpu_or - iterate over every cpu present in either mask + * @cpu: the (optionally unsigned) integer iterator + * @mask1: the first cpumask pointer + * @mask2: the second cpumask pointer + * + * This saves a temporary CPU mask in many places. It is equivalent to: + * struct cpumask tmp; + * cpumask_or(&tmp, &mask1, &mask2); + * for_each_cpu(cpu, &tmp) + * ... + * + * After the loop, cpu is >= nr_cpu_ids. + */ +#define for_each_cpu_or(cpu, mask1, mask2) \ + for_each_or_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), small_cpumask_bits) + +/** * cpumask_any_but - return a "random" in a cpumask, but not this one. * @mask: the cpumask to search * @cpu: the cpu to ignore. |