On 12/26/18 7:50 PM, Matthew Wilcox wrote: > On Wed, Dec 26, 2018 at 01:42:56PM -0600, Aditya Pakki wrote: >> In sysctl_extfrag_handler(), proc_dointvec_minmax() can return an >> error. The fix propagates the error upstream in case of failure. > > Why not just ... Yes, this change (below) makes sense to me. > Mel, Randy? You seem to have been the prime instigators on this. I expect that all I did was move the location of the source code lines of the sysctl, but that is just a guess, based on this commit message: [randy.dunlap@xxxxxxxxxx: Fix build errors when proc fs is not configured] > diff --git a/include/linux/compaction.h b/include/linux/compaction.h > index 68250a57aace..70d0256edd31 100644 > --- a/include/linux/compaction.h > +++ b/include/linux/compaction.h > @@ -88,8 +88,6 @@ extern int sysctl_compact_memory; > extern int sysctl_compaction_handler(struct ctl_table *table, int write, > void __user *buffer, size_t *length, loff_t *ppos); > extern int sysctl_extfrag_threshold; > -extern int sysctl_extfrag_handler(struct ctl_table *table, int write, > - void __user *buffer, size_t *length, loff_t *ppos); > extern int sysctl_compact_unevictable_allowed; > > extern int fragmentation_index(struct zone *zone, unsigned int order); > diff --git a/kernel/sysctl.c b/kernel/sysctl.c > index 5fc724e4e454..e9c69247fc29 100644 > --- a/kernel/sysctl.c > +++ b/kernel/sysctl.c > @@ -1439,7 +1439,7 @@ static struct ctl_table vm_table[] = { > .data = &sysctl_extfrag_threshold, > .maxlen = sizeof(int), > .mode = 0644, > - .proc_handler = sysctl_extfrag_handler, > + .proc_handler = proc_dointvec_minmax, > .extra1 = &min_extfrag_threshold, > .extra2 = &max_extfrag_threshold, > }, > diff --git a/mm/compaction.c b/mm/compaction.c > index 7c607479de4a..80b941d9b6e7 100644 > --- a/mm/compaction.c > +++ b/mm/compaction.c > @@ -1876,14 +1876,6 @@ int sysctl_compaction_handler(struct ctl_table *table, int write, > return 0; > } > > -int sysctl_extfrag_handler(struct ctl_table *table, int write, > - void __user *buffer, size_t *length, loff_t *ppos) > -{ > - proc_dointvec_minmax(table, write, buffer, length, ppos); > - > - return 0; > -} > - > #if defined(CONFIG_SYSFS) && defined(CONFIG_NUMA) > static ssize_t sysfs_compact_node(struct device *dev, > struct device_attribute *attr, > -- ~Randy