Re: [PATCH v1 1/1] mm/vmalloc.c: Fix percpu free VM area search criteria

2019-07-31 Thread Uladzislau Rezki
Hello, Sathyanarayanan. > > Just to clarify, does it mean that on your setup you have only one area > > with the > > 60 size and 0x00 offset? > No, its 2 areas. with offset (0, 00) and size (a0, 60). > > Thank you for clarification, that makes sense to me. I also can

Re: [PATCH v1 1/1] mm/vmalloc.c: Fix percpu free VM area search criteria

2019-07-30 Thread sathyanarayanan kuppuswamy
On 7/30/19 3:34 PM, Uladzislau Rezki wrote: Hello, Sathyanarayanan. I agree with Dave. I don't think this issue is related to NUMA. The problem here is about the logic we use to find appropriate vm_area that satisfies the offset and size requirements of pcpu memory allocator. In my test case

Re: [PATCH v1 1/1] mm/vmalloc.c: Fix percpu free VM area search criteria

2019-07-30 Thread Uladzislau Rezki
Hello, Sathyanarayanan. > > I agree with Dave. I don't think this issue is related to NUMA. The problem > here is about the logic we use to find appropriate vm_area that satisfies > the offset and size requirements of pcpu memory allocator. > > In my test case, I can reproduce this issue if we m

Re: [PATCH v1 1/1] mm/vmalloc.c: Fix percpu free VM area search criteria

2019-07-30 Thread sathyanarayanan kuppuswamy
On 7/30/19 2:55 PM, Dennis Zhou wrote: On Tue, Jul 30, 2019 at 02:13:25PM -0700, sathyanarayanan kuppuswamy wrote: On 7/30/19 1:54 PM, Dave Hansen wrote: On 7/30/19 1:46 PM, Uladzislau Rezki wrote: + /* +* If required width exeeds current VA block, move +

Re: [PATCH v1 1/1] mm/vmalloc.c: Fix percpu free VM area search criteria

2019-07-30 Thread Dennis Zhou
On Tue, Jul 30, 2019 at 02:13:25PM -0700, sathyanarayanan kuppuswamy wrote: > > On 7/30/19 1:54 PM, Dave Hansen wrote: > > On 7/30/19 1:46 PM, Uladzislau Rezki wrote: > > > > + /* > > > > +* If required width exeeds current VA block, move > > > > +* ba

Re: [PATCH v1 1/1] mm/vmalloc.c: Fix percpu free VM area search criteria

2019-07-30 Thread sathyanarayanan kuppuswamy
On 7/30/19 1:54 PM, Dave Hansen wrote: On 7/30/19 1:46 PM, Uladzislau Rezki wrote: + /* +* If required width exeeds current VA block, move +* base downwards and then recheck. +*/ + if (base + end > va->va_end) { +

Re: [PATCH v1 1/1] mm/vmalloc.c: Fix percpu free VM area search criteria

2019-07-30 Thread Dennis Zhou
On Tue, Jul 30, 2019 at 01:54:06PM -0700, Dave Hansen wrote: > On 7/30/19 1:46 PM, Uladzislau Rezki wrote: > >> + /* > >> + * If required width exeeds current VA block, move > >> + * base downwards and then recheck. > >> + */ > >> + if (base + end > v

Re: [PATCH v1 1/1] mm/vmalloc.c: Fix percpu free VM area search criteria

2019-07-30 Thread Dave Hansen
On 7/30/19 1:46 PM, Uladzislau Rezki wrote: >> +/* >> + * If required width exeeds current VA block, move >> + * base downwards and then recheck. >> + */ >> +if (base + end > va->va_end) { >> +base = pvm_determine_end_f

Re: [PATCH v1 1/1] mm/vmalloc.c: Fix percpu free VM area search criteria

2019-07-30 Thread Uladzislau Rezki
On Mon, Jul 29, 2019 at 04:21:39PM -0700, sathyanarayanan.kuppusw...@linux.intel.com wrote: > From: Kuppuswamy Sathyanarayanan > > Recent changes to the vmalloc code by Commit 68ad4a330433 > ("mm/vmalloc.c: keep track of free blocks for vmap allocation") can > cause spurious percpu allocation fa