Re: [PATCH] efifb: allow user to disable write combined mapping.

On 07/18/17 13:44, Dave Airlie wrote: > > In normal operation the console is faster with _wc. It's the side effects > on other cores that is the problem. > I'm guessing leaving these as UC- rate-limits them so it doesn't interfere with the I/O operations on the other cores... -hpa

Re: [PATCH] efifb: allow user to disable write combined mapping.

On 07/18/17 13:44, Dave Airlie wrote: > > In normal operation the console is faster with _wc. It's the side effects > on other cores that is the problem. > I'm guessing leaving these as UC- rate-limits them so it doesn't interfere with the I/O operations on the other cores... -hpa

Re: [PATCH] efifb: allow user to disable write combined mapping.

On Tuesday, July 25, 2017 10:56:15 AM Bartlomiej Zolnierkiewicz wrote: > On Tuesday, July 25, 2017 02:00:00 PM Dave Airlie wrote: > > On 19 July 2017 at 00:34, Peter Jones wrote: > > > On Tue, Jul 18, 2017 at 04:09:09PM +1000, Dave Airlie wrote: > > >> This patch allows the

Re: [PATCH] efifb: allow user to disable write combined mapping.

On Tuesday, July 25, 2017 10:56:15 AM Bartlomiej Zolnierkiewicz wrote: > On Tuesday, July 25, 2017 02:00:00 PM Dave Airlie wrote: > > On 19 July 2017 at 00:34, Peter Jones wrote: > > > On Tue, Jul 18, 2017 at 04:09:09PM +1000, Dave Airlie wrote: > > >> This patch allows the user to disable write

Re: [PATCH] efifb: allow user to disable write combined mapping.

On Tuesday, July 25, 2017 02:00:00 PM Dave Airlie wrote: > On 19 July 2017 at 00:34, Peter Jones wrote: > > On Tue, Jul 18, 2017 at 04:09:09PM +1000, Dave Airlie wrote: > >> This patch allows the user to disable write combined mapping > >> of the efifb framebuffer console using

Re: [PATCH] efifb: allow user to disable write combined mapping.

On Tuesday, July 25, 2017 02:00:00 PM Dave Airlie wrote: > On 19 July 2017 at 00:34, Peter Jones wrote: > > On Tue, Jul 18, 2017 at 04:09:09PM +1000, Dave Airlie wrote: > >> This patch allows the user to disable write combined mapping > >> of the efifb framebuffer console using an nowc option. >

Re: [PATCH] efifb: allow user to disable write combined mapping.

On 19 July 2017 at 00:34, Peter Jones wrote: > On Tue, Jul 18, 2017 at 04:09:09PM +1000, Dave Airlie wrote: >> This patch allows the user to disable write combined mapping >> of the efifb framebuffer console using an nowc option. >> >> A customer noticed major slowdowns while

Re: [PATCH] efifb: allow user to disable write combined mapping.

On 19 July 2017 at 00:34, Peter Jones wrote: > On Tue, Jul 18, 2017 at 04:09:09PM +1000, Dave Airlie wrote: >> This patch allows the user to disable write combined mapping >> of the efifb framebuffer console using an nowc option. >> >> A customer noticed major slowdowns while logging to the

Re: [PATCH] efifb: allow user to disable write combined mapping.

On 20 July 2017 at 14:44, Linus Torvalds wrote: > On Wed, Jul 19, 2017 at 9:28 PM, Andy Lutomirski wrote: >> >> It shouldn't be that hard to hack up efifb to allocate some actual RAM >> as "framebuffer", unmap it from the direct map, and

Re: [PATCH] efifb: allow user to disable write combined mapping.

On 20 July 2017 at 14:44, Linus Torvalds wrote: > On Wed, Jul 19, 2017 at 9:28 PM, Andy Lutomirski wrote: >> >> It shouldn't be that hard to hack up efifb to allocate some actual RAM >> as "framebuffer", unmap it from the direct map, and ioremap_wc() it as >> usual. Then you could see if PCIe

Re: [PATCH] efifb: allow user to disable write combined mapping.

* Linus Torvalds wrote: > On Tue, Jul 18, 2017 at 2:21 PM, Dave Airlie wrote: > > > > Oh and just FYI, the machine I've tested this on has an mgag200 server > > graphics card backing the framebuffer, but with just efifb loaded. > > Yeah, it

Re: [PATCH] efifb: allow user to disable write combined mapping.

* Linus Torvalds wrote: > On Tue, Jul 18, 2017 at 2:21 PM, Dave Airlie wrote: > > > > Oh and just FYI, the machine I've tested this on has an mgag200 server > > graphics card backing the framebuffer, but with just efifb loaded. > > Yeah, it looks like it needs special hardware - and

Re: [PATCH] efifb: allow user to disable write combined mapping.

On Wed, Jul 19, 2017 at 9:28 PM, Andy Lutomirski wrote: > > It shouldn't be that hard to hack up efifb to allocate some actual RAM > as "framebuffer", unmap it from the direct map, and ioremap_wc() it as > usual. Then you could see if PCIe is important for it. The thing is, the

Re: [PATCH] efifb: allow user to disable write combined mapping.

On Wed, Jul 19, 2017 at 9:28 PM, Andy Lutomirski wrote: > > It shouldn't be that hard to hack up efifb to allocate some actual RAM > as "framebuffer", unmap it from the direct map, and ioremap_wc() it as > usual. Then you could see if PCIe is important for it. The thing is, the "actual RAM"

Re: [PATCH] efifb: allow user to disable write combined mapping.

On Wed, Jul 19, 2017 at 9:07 PM, Dave Airlie wrote: > > Yes hoping someone can give some insight. > > Scrap the multi-socket it's been seen on a single-socket, but not as > drastic, 2x rather than 10x slowdowns. > > It's starting to seem like the commonality might be the Matrox

Re: [PATCH] efifb: allow user to disable write combined mapping.

On Wed, Jul 19, 2017 at 9:07 PM, Dave Airlie wrote: > > Yes hoping someone can give some insight. > > Scrap the multi-socket it's been seen on a single-socket, but not as > drastic, 2x rather than 10x slowdowns. > > It's starting to seem like the commonality might be the Matrox G200EH > which is

Re: [PATCH] efifb: allow user to disable write combined mapping.

On 19 July 2017 at 11:15, Linus Torvalds wrote: > On Tue, Jul 18, 2017 at 5:00 PM, Dave Airlie wrote: >> >> More digging: >> Single CPU system: >> Intel(R) Xeon(R) CPU E5-2620 v2 @ 2.10GHz >> 01:00.1 VGA compatible controller: Matrox Electronics

Re: [PATCH] efifb: allow user to disable write combined mapping.

On 19 July 2017 at 11:15, Linus Torvalds wrote: > On Tue, Jul 18, 2017 at 5:00 PM, Dave Airlie wrote: >> >> More digging: >> Single CPU system: >> Intel(R) Xeon(R) CPU E5-2620 v2 @ 2.10GHz >> 01:00.1 VGA compatible controller: Matrox Electronics Systems Ltd. MGA G200EH >> >> Now I can't get

Re: [PATCH] efifb: allow user to disable write combined mapping.

On Tue, Jul 18, 2017 at 5:00 PM, Dave Airlie wrote: > > More digging: > Single CPU system: > Intel(R) Xeon(R) CPU E5-2620 v2 @ 2.10GHz > 01:00.1 VGA compatible controller: Matrox Electronics Systems Ltd. MGA G200EH > > Now I can't get efifb to load on this (due to it being

Re: [PATCH] efifb: allow user to disable write combined mapping.

On Tue, Jul 18, 2017 at 5:00 PM, Dave Airlie wrote: > > More digging: > Single CPU system: > Intel(R) Xeon(R) CPU E5-2620 v2 @ 2.10GHz > 01:00.1 VGA compatible controller: Matrox Electronics Systems Ltd. MGA G200EH > > Now I can't get efifb to load on this (due to it being remote and I've > no

Re: [PATCH] efifb: allow user to disable write combined mapping.

On 19 July 2017 at 09:16, Dave Airlie wrote: > On 19 July 2017 at 09:16, Dave Airlie wrote: >> On 19 July 2017 at 08:22, Linus Torvalds >> wrote: >>> On Tue, Jul 18, 2017 at 2:21 PM, Dave Airlie wrote:

Re: [PATCH] efifb: allow user to disable write combined mapping.

On 19 July 2017 at 09:16, Dave Airlie wrote: > On 19 July 2017 at 09:16, Dave Airlie wrote: >> On 19 July 2017 at 08:22, Linus Torvalds >> wrote: >>> On Tue, Jul 18, 2017 at 2:21 PM, Dave Airlie wrote: Oh and just FYI, the machine I've tested this on has an mgag200 server

Re: [PATCH] efifb: allow user to disable write combined mapping.

On 19 July 2017 at 09:16, Dave Airlie wrote: > On 19 July 2017 at 08:22, Linus Torvalds > wrote: >> On Tue, Jul 18, 2017 at 2:21 PM, Dave Airlie wrote: >>> >>> Oh and just FYI, the machine I've tested this on has an mgag200

Re: [PATCH] efifb: allow user to disable write combined mapping.

On 19 July 2017 at 09:16, Dave Airlie wrote: > On 19 July 2017 at 08:22, Linus Torvalds > wrote: >> On Tue, Jul 18, 2017 at 2:21 PM, Dave Airlie wrote: >>> >>> Oh and just FYI, the machine I've tested this on has an mgag200 server >>> graphics card backing the framebuffer, but with just efifb

Re: [PATCH] efifb: allow user to disable write combined mapping.

On 19 July 2017 at 08:22, Linus Torvalds wrote: > On Tue, Jul 18, 2017 at 2:21 PM, Dave Airlie wrote: >> >> Oh and just FYI, the machine I've tested this on has an mgag200 server >> graphics card backing the framebuffer, but with just efifb

Re: [PATCH] efifb: allow user to disable write combined mapping.

On 19 July 2017 at 08:22, Linus Torvalds wrote: > On Tue, Jul 18, 2017 at 2:21 PM, Dave Airlie wrote: >> >> Oh and just FYI, the machine I've tested this on has an mgag200 server >> graphics card backing the framebuffer, but with just efifb loaded. > > Yeah, it looks like it needs special

Re: [PATCH] efifb: allow user to disable write combined mapping.

On Tue, Jul 18, 2017 at 2:21 PM, Dave Airlie wrote: > > Oh and just FYI, the machine I've tested this on has an mgag200 server > graphics card backing the framebuffer, but with just efifb loaded. Yeah, it looks like it needs special hardware - and particularly the kind of

Re: [PATCH] efifb: allow user to disable write combined mapping.

On Tue, Jul 18, 2017 at 2:21 PM, Dave Airlie wrote: > > Oh and just FYI, the machine I've tested this on has an mgag200 server > graphics card backing the framebuffer, but with just efifb loaded. Yeah, it looks like it needs special hardware - and particularly the kind of garbage hardware that

Re: [PATCH] efifb: allow user to disable write combined mapping.

On 19 July 2017 at 06:44, Dave Airlie wrote: > On 19 July 2017 at 05:57, Linus Torvalds > wrote: >> On Tue, Jul 18, 2017 at 7:34 AM, Peter Jones wrote: >>> >>> Well, that's kind of amazing, given 3c004b4f7eab239e switched us

Re: [PATCH] efifb: allow user to disable write combined mapping.

On 19 July 2017 at 06:44, Dave Airlie wrote: > On 19 July 2017 at 05:57, Linus Torvalds > wrote: >> On Tue, Jul 18, 2017 at 7:34 AM, Peter Jones wrote: >>> >>> Well, that's kind of amazing, given 3c004b4f7eab239e switched us /to/ >>> using ioremap_wc() for the exact same reason. I'm not

Re: [PATCH] efifb: allow user to disable write combined mapping.

On 19 July 2017 at 05:57, Linus Torvalds wrote: > On Tue, Jul 18, 2017 at 7:34 AM, Peter Jones wrote: >> >> Well, that's kind of amazing, given 3c004b4f7eab239e switched us /to/ >> using ioremap_wc() for the exact same reason. I'm not against

Re: [PATCH] efifb: allow user to disable write combined mapping.

On 19 July 2017 at 05:57, Linus Torvalds wrote: > On Tue, Jul 18, 2017 at 7:34 AM, Peter Jones wrote: >> >> Well, that's kind of amazing, given 3c004b4f7eab239e switched us /to/ >> using ioremap_wc() for the exact same reason. I'm not against letting >> the user force one way or the other if it

Re: [PATCH] efifb: allow user to disable write combined mapping.

On Tue, Jul 18, 2017 at 7:34 AM, Peter Jones wrote: > > Well, that's kind of amazing, given 3c004b4f7eab239e switched us /to/ > using ioremap_wc() for the exact same reason. I'm not against letting > the user force one way or the other if it helps, though it sure would be >

Re: [PATCH] efifb: allow user to disable write combined mapping.

On Tue, Jul 18, 2017 at 7:34 AM, Peter Jones wrote: > > Well, that's kind of amazing, given 3c004b4f7eab239e switched us /to/ > using ioremap_wc() for the exact same reason. I'm not against letting > the user force one way or the other if it helps, though it sure would be > nice to know why.

Re: [PATCH] efifb: allow user to disable write combined mapping.

On Tue, Jul 18, 2017 at 04:09:09PM +1000, Dave Airlie wrote: > This patch allows the user to disable write combined mapping > of the efifb framebuffer console using an nowc option. > > A customer noticed major slowdowns while logging to the console > with write combining enabled, on other tasks

Re: [PATCH] efifb: allow user to disable write combined mapping.

On Tue, Jul 18, 2017 at 04:09:09PM +1000, Dave Airlie wrote: > This patch allows the user to disable write combined mapping > of the efifb framebuffer console using an nowc option. > > A customer noticed major slowdowns while logging to the console > with write combining enabled, on other tasks

[PATCH] efifb: allow user to disable write combined mapping.

This patch allows the user to disable write combined mapping of the efifb framebuffer console using an nowc option. A customer noticed major slowdowns while logging to the console with write combining enabled, on other tasks running on the same CPU. (10x or greater slow down on all other cores on

[PATCH] efifb: allow user to disable write combined mapping.

This patch allows the user to disable write combined mapping of the efifb framebuffer console using an nowc option. A customer noticed major slowdowns while logging to the console with write combining enabled, on other tasks running on the same CPU. (10x or greater slow down on all other cores on