Messages in this thread | | | Date | Fri, 27 Jan 2023 20:57:55 +0530 | Subject | Re: [RFC PATCH V1 1/1] sched/numa: Enhance vma scanning logic | From | Raghavendra K T <> |
| |
On 1/27/2023 3:47 PM, Mel Gorman wrote: > On Wed, Jan 25, 2023 at 12:48:16AM +0530, Raghavendra K T wrote: >> looks like we have to additionally handle numab initialization in >> vm_area_dup() code path. something like below fixed it (copied pasted >> from tty): >> > > Yep, it wasn't even boot tested. Better approach is something like this, > still not actually tested > > include/linux/mm.h | 9 +++++++++ > include/linux/mm_types.h | 7 +++++++ > kernel/fork.c | 2 ++ > kernel/sched/fair.c | 17 +++++++++++++++++ > 4 files changed, 35 insertions(+) > > diff --git a/include/linux/mm.h b/include/linux/mm.h > index 8f857163ac89..481f90dc1983 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -612,6 +612,14 @@ struct vm_operations_struct { > unsigned long addr); > }; > > +#ifdef CONFIG_NUMA_BALANCING > +#define vma_numab_init(vma) do { (vma)->numab = NULL; } while (0) > +#define vma_numab_free(vma) do { kfree((vma)->numab); } while (0) > +#else > +static inline void vma_numab_init(struct vm_area_struct *vma) {} > +static inline void vma_numab_free(struct vm_area_struct *vma) {} > +#endif /* CONFIG_NUMA_BALANCING */ > + > static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm) > { > static const struct vm_operations_struct dummy_vm_ops = {}; > @@ -620,6 +628,7 @@ static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm) > vma->vm_mm = mm; > vma->vm_ops = &dummy_vm_ops; > INIT_LIST_HEAD(&vma->anon_vma_chain); > + vma_numab_init(vma); > } > > static inline void vma_set_anonymous(struct vm_area_struct *vma) > diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h > index 9757067c3053..43ce363d5124 100644 > --- a/include/linux/mm_types.h > +++ b/include/linux/mm_types.h > @@ -526,6 +526,10 @@ struct anon_vma_name { > char name[]; > }; > > +struct vma_numab { > + unsigned long next_scan; > +}; > + > /* > * This struct describes a virtual memory area. There is one of these > * per VM-area/task. A VM area is any part of the process virtual memory > @@ -593,6 +597,9 @@ struct vm_area_struct { > #endif > #ifdef CONFIG_NUMA > struct mempolicy *vm_policy; /* NUMA policy for the VMA */ > +#endif > +#ifdef CONFIG_NUMA_BALANCING > + struct vma_numab *numab; /* NUMA Balancing state */ > #endif > struct vm_userfaultfd_ctx vm_userfaultfd_ctx; > } __randomize_layout; > diff --git a/kernel/fork.c b/kernel/fork.c > index 9f7fe3541897..5a2e8c3cc410 100644 > --- a/kernel/fork.c > +++ b/kernel/fork.c > @@ -474,6 +474,7 @@ struct vm_area_struct *vm_area_dup(struct vm_area_struct *orig) > */ > *new = data_race(*orig); > INIT_LIST_HEAD(&new->anon_vma_chain); > + vma_numab_init(new); > dup_anon_vma_name(orig, new); > } > return new; > @@ -481,6 +482,7 @@ struct vm_area_struct *vm_area_dup(struct vm_area_struct *orig) > > void vm_area_free(struct vm_area_struct *vma) > { > + vma_numab_free(vma); > free_anon_vma_name(vma); > kmem_cache_free(vm_area_cachep, vma); > } > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index c36aa54ae071..6a1cffdfc76b 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -3027,6 +3027,23 @@ static void task_numa_work(struct callback_head *work) > if (!vma_is_accessible(vma)) > continue; > > + /* Initialise new per-VMA NUMAB state. */ > + if (!vma->numab) { > + vma->numab = kzalloc(sizeof(struct vma_numab), GFP_KERNEL); > + if (!vma->numab) > + continue; > + > + vma->numab->next_scan = now + > + msecs_to_jiffies(sysctl_numa_balancing_scan_delay); > + } > + > + /* > + * After the first scan is complete, delay the balancing scan > + * for new VMAs. > + */ > + if (mm->numa_scan_seq && time_before(jiffies, vma->numab->next_scan)) > + continue; > + > do { > start = max(start, vma->vm_start); > end = ALIGN(start + (pages << PAGE_SHIFT), HPAGE_SIZE);
Thank you Mel. This looks better now. Yes we would have moved to mm.h eventually to avoid #if clutter.
Also for PATCH2 function common to memory.c and huge_memory.c would need the same to handle hugetlb vma as suggested by you. Working on gathering numbers and PID clear logic now. will post V2 soon.
Thanks - Raghu
| |