* Re: [RFC] The meaning of local_cpulist and local_cpus [not found] <CAG82n_ni9ZAThGbMfqqObnz7QyQpH18G4hYBLt+BdeRHPE6EBg@mail.gmail.com> @ 2013-04-24 16:48 ` Bjorn Helgaas 2013-04-24 16:56 ` Mike Travis 0 siblings, 1 reply; 4+ messages in thread From: Bjorn Helgaas @ 2013-04-24 16:48 UTC (permalink / raw) To: Bian LuLu Cc: linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, Mike Travis [+cc linux-pci, Mike] On Wed, Apr 24, 2013 at 4:06 AM, Bian LuLu <helianthus.lu@gmail.com> wrote: > Hi all, > > Recently, i read some codes of PCI portions. I think > local_cpulist is a list about one kind of CPU and > local_cpus is a mask of CPU. But i am not sure when > and how i should use these two parameters. > > See http://lxr.linux.no/linux+v3.5.4/drivers/pci/pci-sysfs.c#L390 for > details. > > Would anyone please give me some suggestions? > Thanks in advance ;-) I don't know off-hand, but maybe Mike or somebody on linux-pci does. It looks like Mike added local_cpulist with 39106dcf85. ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [RFC] The meaning of local_cpulist and local_cpus 2013-04-24 16:48 ` [RFC] The meaning of local_cpulist and local_cpus Bjorn Helgaas @ 2013-04-24 16:56 ` Mike Travis 2013-04-25 13:57 ` Bian LuLu 0 siblings, 1 reply; 4+ messages in thread From: Mike Travis @ 2013-04-24 16:56 UTC (permalink / raw) To: Bjorn Helgaas Cc: Bian LuLu, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org On 4/24/2013 9:48 AM, Bjorn Helgaas wrote: > [+cc linux-pci, Mike] > > On Wed, Apr 24, 2013 at 4:06 AM, Bian LuLu <helianthus.lu@gmail.com> wrote: >> Hi all, >> >> Recently, i read some codes of PCI portions. I think >> local_cpulist is a list about one kind of CPU and >> local_cpus is a mask of CPU. But i am not sure when >> and how i should use these two parameters. >> >> See http://lxr.linux.no/linux+v3.5.4/drivers/pci/pci-sysfs.c#L390 for >> details. >> >> Would anyone please give me some suggestions? >> Thanks in advance ;-) > > I don't know off-hand, but maybe Mike or somebody on linux-pci does. > It looks like Mike added local_cpulist with 39106dcf85. > It primarily comes into play when you have a large # of cpus. Here's the difference on a system that has 1024 cpu threads: harp31-sys:/sys/devices/system/node/node20 # cat cpulist 160-167,672-679 harp31-sys:/sys/devices/system/node/node20 # cat cpumap 00000000,00000000,00000000,00000000,00000000,00000000,00000000, 00000000,00000000,00000000,000000ff,00000000,00000000,00000000, 00000000,00000000,00000000,00000000,00000000,00000000,00000000, 00000000,00000000,00000000,00000000,00000000,000000ff,00000000, 00000000,00000000,00000000,00000000 Which is easier to interpret? :) But there are some older user side utilities that still use the mask format. ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [RFC] The meaning of local_cpulist and local_cpus 2013-04-24 16:56 ` Mike Travis @ 2013-04-25 13:57 ` Bian LuLu 2013-04-25 14:17 ` Mike Travis 0 siblings, 1 reply; 4+ messages in thread From: Bian LuLu @ 2013-04-25 13:57 UTC (permalink / raw) To: Mike Travis Cc: Bjorn Helgaas, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org Thankyou . But I still can not understand what is the meaning of cuplist. my linux version is ubuntu 12.04, and my system:/$ cat /sys/devices/pci0000:00/0000:00:1a.0/local_cpulist the result is '0-7', I just don't konw what are they represent .Could you give me more detailed information about local_cpulist and local_cpus,and their relations. thanks in advance :) On Thu, Apr 25, 2013 at 12:56 AM, Mike Travis <travis@sgi.com> wrote: > > > On 4/24/2013 9:48 AM, Bjorn Helgaas wrote: >> [+cc linux-pci, Mike] >> >> On Wed, Apr 24, 2013 at 4:06 AM, Bian LuLu <helianthus.lu@gmail.com> wrote: >>> Hi all, >>> >>> Recently, i read some codes of PCI portions. I think >>> local_cpulist is a list about one kind of CPU and >>> local_cpus is a mask of CPU. But i am not sure when >>> and how i should use these two parameters. >>> >>> See http://lxr.linux.no/linux+v3.5.4/drivers/pci/pci-sysfs.c#L390 for >>> details. >>> >>> Would anyone please give me some suggestions? >>> Thanks in advance ;-) >> >> I don't know off-hand, but maybe Mike or somebody on linux-pci does. >> It looks like Mike added local_cpulist with 39106dcf85. >> > > It primarily comes into play when you have a large # of cpus. I can not understand the symbol of '#' ,what is the meaning of it? > Here's the difference on a system that has 1024 cpu threads: > > harp31-sys:/sys/devices/system/node/node20 # cat cpulist > 160-167,672-679 > harp31-sys:/sys/devices/system/node/node20 # cat cpumap > 00000000,00000000,00000000,00000000,00000000,00000000,00000000, > 00000000,00000000,00000000,000000ff,00000000,00000000,00000000, > 00000000,00000000,00000000,00000000,00000000,00000000,00000000, > 00000000,00000000,00000000,00000000,00000000,000000ff,00000000, > 00000000,00000000,00000000,00000000 > > Which is easier to interpret? :) > > But there are some older user side utilities that still > use the mask format. ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [RFC] The meaning of local_cpulist and local_cpus 2013-04-25 13:57 ` Bian LuLu @ 2013-04-25 14:17 ` Mike Travis 0 siblings, 0 replies; 4+ messages in thread From: Mike Travis @ 2013-04-25 14:17 UTC (permalink / raw) To: Bian LuLu Cc: Bjorn Helgaas, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org On 4/25/2013 6:57 AM, Bian LuLu wrote: > Thankyou . > But I still can not understand what is the meaning of cuplist. > my linux version is ubuntu 12.04, and > my system:/$ cat /sys/devices/pci0000:00/0000:00:1a.0/local_cpulist > the result is '0-7', Ahh, sorry, I misinterpreted what you are asking. On NUMA systems, I/O can be spread over many nodes and DMA/interrupts are faster from the device to memory and cpus local to that node. The numa_node shows which node the device is on, and the cpulist shows which cpus are local to that same node. In general you also want the IRQ affinity to be the local cpus as well. > > I just don't konw what are they represent .Could you give me more > detailed information about local_cpulist and local_cpus,and their > relations. > thanks in advance :) > > On Thu, Apr 25, 2013 at 12:56 AM, Mike Travis <travis@sgi.com> wrote: >> >> >> On 4/24/2013 9:48 AM, Bjorn Helgaas wrote: >>> [+cc linux-pci, Mike] >>> >>> On Wed, Apr 24, 2013 at 4:06 AM, Bian LuLu <helianthus.lu@gmail.com> wrote: >>>> Hi all, >>>> >>>> Recently, i read some codes of PCI portions. I think >>>> local_cpulist is a list about one kind of CPU and >>>> local_cpus is a mask of CPU. But i am not sure when >>>> and how i should use these two parameters. >>>> >>>> See http://lxr.linux.no/linux+v3.5.4/drivers/pci/pci-sysfs.c#L390 for >>>> details. >>>> >>>> Would anyone please give me some suggestions? >>>> Thanks in advance ;-) >>> >>> I don't know off-hand, but maybe Mike or somebody on linux-pci does. >>> It looks like Mike added local_cpulist with 39106dcf85. >>> >> >> It primarily comes into play when you have a large # of cpus. > I can not understand the symbol of '#' ,what is the meaning of it? >> Here's the difference on a system that has 1024 cpu threads: >> >> harp31-sys:/sys/devices/system/node/node20 # cat cpulist >> 160-167,672-679 >> harp31-sys:/sys/devices/system/node/node20 # cat cpumap >> 00000000,00000000,00000000,00000000,00000000,00000000,00000000, >> 00000000,00000000,00000000,000000ff,00000000,00000000,00000000, >> 00000000,00000000,00000000,00000000,00000000,00000000,00000000, >> 00000000,00000000,00000000,00000000,00000000,000000ff,00000000, >> 00000000,00000000,00000000,00000000 >> >> Which is easier to interpret? :) >> >> But there are some older user side utilities that still >> use the mask format. ^ permalink raw reply [flat|nested] 4+ messages in thread
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[not found] <CAG82n_ni9ZAThGbMfqqObnz7QyQpH18G4hYBLt+BdeRHPE6EBg@mail.gmail.com>
2013-04-24 16:48 ` [RFC] The meaning of local_cpulist and local_cpus Bjorn Helgaas
2013-04-24 16:56 ` Mike Travis
2013-04-25 13:57 ` Bian LuLu
2013-04-25 14:17 ` Mike Travis
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