Re: [PATCH v2] packet: track ring entry use using a shadow ring to prevent RX ring overrun

i.ro...@intel.com>; Reshetova, Elena <elena.reshet...@intel.com>; >> Mike Maloney >> <malo...@google.com>; Benjamin Poirier <bpoir...@suse.com>; Thomas Gleixner >> <t...@linutronix.de>; Greg >> Kroah-Hartman <gre...@linuxfoundation.org>; open

RE: [PATCH v2] packet: track ring entry use using a shadow ring to prevent RX ring overrun

amin Poirier <bpoir...@suse.com>; Thomas Gleixner > <t...@linutronix.de>; Greg > Kroah-Hartman <gre...@linuxfoundation.org>; open list:NETWORKING [GENERAL] > <netdev@vger.kernel.org>; > open list <linux-ker...@vger.kernel.org> > Subject: Re: [PATCH v2] pa

Re: [PATCH v2] packet: track ring entry use using a shadow ring to prevent RX ring overrun

On Wed, May 23, 2018 at 7:54 AM, Jon Rosen (jrosen) wrote: >> > For the ring, there is no requirement to allocate exactly the amount >> > specified by the user request. Safer than relying on shared memory >> > and simpler than the extra allocation in this patch would be to

RE: [PATCH v2] packet: track ring entry use using a shadow ring to prevent RX ring overrun

> > For the ring, there is no requirement to allocate exactly the amount > > specified by the user request. Safer than relying on shared memory > > and simpler than the extra allocation in this patch would be to allocate > > extra shadow memory at the end of the ring (and not mmap that). > > > >

RE: [PATCH v2] packet: track ring entry use using a shadow ring to prevent RX ring overrun

> >>> I think the bigger issues as you've pointed out are the cost of > >>> the additional spin lock and should the additional state be > >>> stored in-band (fewer cache lines) or out-of band (less risk of > >>> breaking due to unpredictable application behavior). > >> > >> We don't need the

Re: [PATCH v2] packet: track ring entry use using a shadow ring to prevent RX ring overrun

On Tue, May 22, 2018 at 10:12 AM, Jon Rosen (jrosen) wrote: > On Monday, May 21, 2018 2:17 PM, Jon Rosen (jrosen) wrote: >> On Monday, May 21, 2018 1:07 PM, Willem de Bruijn >> wrote: >>> On Mon, May 21, 2018 at 8:57 AM, Jon

Re: [PATCH v2] packet: track ring entry use using a shadow ring to prevent RX ring overrun

>>> I think the bigger issues as you've pointed out are the cost of >>> the additional spin lock and should the additional state be >>> stored in-band (fewer cache lines) or out-of band (less risk of >>> breaking due to unpredictable application behavior). >> >> We don't need the spinlock if

RE: [PATCH v2] packet: track ring entry use using a shadow ring to prevent RX ring overrun

On Monday, May 21, 2018 2:17 PM, Jon Rosen (jrosen) wrote: > On Monday, May 21, 2018 1:07 PM, Willem de Bruijn > wrote: >> On Mon, May 21, 2018 at 8:57 AM, Jon Rosen (jrosen) wrote: ...snip... >> >> A setsockopt for

RE: [PATCH v2] packet: track ring entry use using a shadow ring to prevent RX ring overrun

On Monday, May 21, 2018 1:07 PM, Willem de Bruijn wrote: >On Mon, May 21, 2018 at 8:57 AM, Jon Rosen (jrosen) wrote: >> On Sunday, May 20, 2018 7:22 PM, Willem de Bruijn >> wrote: >>> On Sun, May 20, 2018 at

Re: [PATCH v2] packet: track ring entry use using a shadow ring to prevent RX ring overrun

On Mon, May 21, 2018 at 8:57 AM, Jon Rosen (jrosen) wrote: > On Sunday, May 20, 2018 7:22 PM, Willem de Bruijn > wrote: >> On Sun, May 20, 2018 at 6:51 PM, Willem de Bruijn >> wrote: >>> On Sat, May 19, 2018 at

RE: [PATCH v2] packet: track ring entry use using a shadow ring to prevent RX ring overrun

On Sunday, May 20, 2018 7:22 PM, Willem de Bruijn wrote: > On Sun, May 20, 2018 at 6:51 PM, Willem de Bruijn > wrote: >> On Sat, May 19, 2018 at 8:07 AM, Jon Rosen wrote: >>> Fix PACKET_RX_RING bug for versions

Re: [PATCH v2] packet: track ring entry use using a shadow ring to prevent RX ring overrun

On Sun, May 20, 2018 at 6:51 PM, Willem de Bruijn wrote: > On Sat, May 19, 2018 at 8:07 AM, Jon Rosen wrote: >> Fix PACKET_RX_RING bug for versions TPACKET_V1 and TPACKET_V2 which >> casues the ring to get corrupted by allowing multiple kernel

Re: [PATCH v2] packet: track ring entry use using a shadow ring to prevent RX ring overrun

On Sat, May 19, 2018 at 8:07 AM, Jon Rosen wrote: > Fix PACKET_RX_RING bug for versions TPACKET_V1 and TPACKET_V2 which > casues the ring to get corrupted by allowing multiple kernel threads > to claim ownership of the same ring entry. Track ownership in a shadow > ring

[PATCH v2] packet: track ring entry use using a shadow ring to prevent RX ring overrun

Fix PACKET_RX_RING bug for versions TPACKET_V1 and TPACKET_V2 which casues the ring to get corrupted by allowing multiple kernel threads to claim ownership of the same ring entry. Track ownership in a shadow ring structure to prevent other kernel threads from reusing the same entry before it's