Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-28 Thread Christoph Hellwig
On Thu, Jun 28, 2018 at 08:38:34AM +0800, Ye Xiaolong wrote: > Update the result: > > testcase/path_params/tbox_group/run: will-it-scale/poll2-performance/lkp-sb03 So this looks like a huge improvement in the per process ops, but not as large as the original regression, and no change in the

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-28 Thread Christoph Hellwig
On Thu, Jun 28, 2018 at 08:38:34AM +0800, Ye Xiaolong wrote: > Update the result: > > testcase/path_params/tbox_group/run: will-it-scale/poll2-performance/lkp-sb03 So this looks like a huge improvement in the per process ops, but not as large as the original regression, and no change in the

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-27 Thread Ye Xiaolong
On 06/27, Christoph Hellwig wrote: >On Tue, Jun 26, 2018 at 02:03:38PM +0800, Ye Xiaolong wrote: >> Hi, >> >> On 06/22, Christoph Hellwig wrote: >> >Hi Xiaolong, >> > >> >can you retest this workload on the following branch: >> > >> >git://git.infradead.org/users/hch/vfs.git

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-27 Thread Ye Xiaolong
On 06/27, Christoph Hellwig wrote: >On Tue, Jun 26, 2018 at 02:03:38PM +0800, Ye Xiaolong wrote: >> Hi, >> >> On 06/22, Christoph Hellwig wrote: >> >Hi Xiaolong, >> > >> >can you retest this workload on the following branch: >> > >> >git://git.infradead.org/users/hch/vfs.git

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-27 Thread Christoph Hellwig
On Tue, Jun 26, 2018 at 02:03:38PM +0800, Ye Xiaolong wrote: > Hi, > > On 06/22, Christoph Hellwig wrote: > >Hi Xiaolong, > > > >can you retest this workload on the following branch: > > > >git://git.infradead.org/users/hch/vfs.git remove-get-poll-head > > > >Gitweb: > > > > > >

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-27 Thread Christoph Hellwig
On Tue, Jun 26, 2018 at 02:03:38PM +0800, Ye Xiaolong wrote: > Hi, > > On 06/22, Christoph Hellwig wrote: > >Hi Xiaolong, > > > >can you retest this workload on the following branch: > > > >git://git.infradead.org/users/hch/vfs.git remove-get-poll-head > > > >Gitweb: > > > > > >

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-26 Thread Ye Xiaolong
Hi, On 06/22, Christoph Hellwig wrote: >Hi Xiaolong, > >can you retest this workload on the following branch: > >git://git.infradead.org/users/hch/vfs.git remove-get-poll-head > >Gitweb: > > > http://git.infradead.org/users/hch/vfs.git/shortlog/refs/heads/remove-get-poll-head Here is the

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-26 Thread Ye Xiaolong
Hi, On 06/22, Christoph Hellwig wrote: >Hi Xiaolong, > >can you retest this workload on the following branch: > >git://git.infradead.org/users/hch/vfs.git remove-get-poll-head > >Gitweb: > > > http://git.infradead.org/users/hch/vfs.git/shortlog/refs/heads/remove-get-poll-head Here is the

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-23 Thread Christoph Hellwig
On Fri, Jun 22, 2018 at 09:02:55PM +0100, Al Viro wrote: > > While at the same time corect poll code already checks net_busy_loop_on > > to set POLL_BUSY_LOOP. So except for sockets where people set the > > timeout to 0 the code already does the right thing as-is. IMHO not > > really worth

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-23 Thread Christoph Hellwig
On Fri, Jun 22, 2018 at 09:02:55PM +0100, Al Viro wrote: > > While at the same time corect poll code already checks net_busy_loop_on > > to set POLL_BUSY_LOOP. So except for sockets where people set the > > timeout to 0 the code already does the right thing as-is. IMHO not > > really worth

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Al Viro
On Fri, Jun 22, 2018 at 06:18:02PM +0200, Christoph Hellwig wrote: > On Fri, Jun 22, 2018 at 05:28:50PM +0200, Christoph Hellwig wrote: > > On Fri, Jun 22, 2018 at 04:14:09PM +0100, Al Viro wrote: > > > > > > > >

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Al Viro
On Fri, Jun 22, 2018 at 06:18:02PM +0200, Christoph Hellwig wrote: > On Fri, Jun 22, 2018 at 05:28:50PM +0200, Christoph Hellwig wrote: > > On Fri, Jun 22, 2018 at 04:14:09PM +0100, Al Viro wrote: > > > > > > > >

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Sean Paul
On Fri, Jun 22, 2018 at 7:01 AM Al Viro wrote: > > On Fri, Jun 22, 2018 at 12:00:14PM +0200, Christoph Hellwig wrote: > > And a version with select() also covered: > > For fuck sake, if you want vfs_poll() inlined, *make* *it* *inlined*. > Is there any reason for not doing that other than

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Sean Paul
On Fri, Jun 22, 2018 at 7:01 AM Al Viro wrote: > > On Fri, Jun 22, 2018 at 12:00:14PM +0200, Christoph Hellwig wrote: > > And a version with select() also covered: > > For fuck sake, if you want vfs_poll() inlined, *make* *it* *inlined*. > Is there any reason for not doing that other than

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Christoph Hellwig
On Fri, Jun 22, 2018 at 05:28:50PM +0200, Christoph Hellwig wrote: > On Fri, Jun 22, 2018 at 04:14:09PM +0100, Al Viro wrote: > > > > > > http://git.infradead.org/users/hch/vfs.git/shortlog/refs/heads/remove-get-poll-head > > > > See objections upthread re "fs,net: move poll busy loop

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Christoph Hellwig
On Fri, Jun 22, 2018 at 05:28:50PM +0200, Christoph Hellwig wrote: > On Fri, Jun 22, 2018 at 04:14:09PM +0100, Al Viro wrote: > > > > > > http://git.infradead.org/users/hch/vfs.git/shortlog/refs/heads/remove-get-poll-head > > > > See objections upthread re "fs,net: move poll busy loop

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Christoph Hellwig
On Fri, Jun 22, 2018 at 04:14:09PM +0100, Al Viro wrote: > > > > http://git.infradead.org/users/hch/vfs.git/shortlog/refs/heads/remove-get-poll-head > > See objections upthread re "fs,net: move poll busy loop handling into a > separate method"; as for the next one... I'd like an ACK from

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Christoph Hellwig
On Fri, Jun 22, 2018 at 04:14:09PM +0100, Al Viro wrote: > > > > http://git.infradead.org/users/hch/vfs.git/shortlog/refs/heads/remove-get-poll-head > > See objections upthread re "fs,net: move poll busy loop handling into a > separate method"; as for the next one... I'd like an ACK from

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Al Viro
On Fri, Jun 22, 2018 at 05:02:51PM +0200, Christoph Hellwig wrote: > Hi Xiaolong, > > can you retest this workload on the following branch: > > git://git.infradead.org/users/hch/vfs.git remove-get-poll-head > > Gitweb: > > >

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Al Viro
On Fri, Jun 22, 2018 at 05:02:51PM +0200, Christoph Hellwig wrote: > Hi Xiaolong, > > can you retest this workload on the following branch: > > git://git.infradead.org/users/hch/vfs.git remove-get-poll-head > > Gitweb: > > >

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Christoph Hellwig
Hi Xiaolong, can you retest this workload on the following branch: git://git.infradead.org/users/hch/vfs.git remove-get-poll-head Gitweb: http://git.infradead.org/users/hch/vfs.git/shortlog/refs/heads/remove-get-poll-head

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Christoph Hellwig
Hi Xiaolong, can you retest this workload on the following branch: git://git.infradead.org/users/hch/vfs.git remove-get-poll-head Gitweb: http://git.infradead.org/users/hch/vfs.git/shortlog/refs/heads/remove-get-poll-head

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Al Viro
On Fri, Jun 22, 2018 at 02:33:07PM +0200, Christoph Hellwig wrote: > On Fri, Jun 22, 2018 at 01:17:22PM +0100, Al Viro wrote: > > > The problem is that call to sk_busy_loop(), which is going to be indirect > > > no matter what. > > > > if ->f_poll_head is NULL { > > use ->poll > >

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Al Viro
On Fri, Jun 22, 2018 at 02:33:07PM +0200, Christoph Hellwig wrote: > On Fri, Jun 22, 2018 at 01:17:22PM +0100, Al Viro wrote: > > > The problem is that call to sk_busy_loop(), which is going to be indirect > > > no matter what. > > > > if ->f_poll_head is NULL { > > use ->poll > >

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Christoph Hellwig
On Fri, Jun 22, 2018 at 01:17:22PM +0100, Al Viro wrote: > > The problem is that call to sk_busy_loop(), which is going to be indirect > > no matter what. > > if ->f_poll_head is NULL { > use ->poll > } else { > if can ll_poll (checked in ->f_mode) >

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Christoph Hellwig
On Fri, Jun 22, 2018 at 01:17:22PM +0100, Al Viro wrote: > > The problem is that call to sk_busy_loop(), which is going to be indirect > > no matter what. > > if ->f_poll_head is NULL { > use ->poll > } else { > if can ll_poll (checked in ->f_mode) >

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Al Viro
On Fri, Jun 22, 2018 at 02:07:39PM +0200, Christoph Hellwig wrote: > On Fri, Jun 22, 2018 at 12:56:13PM +0100, Al Viro wrote: > > So mark that in ->f_mode - I strongly suspect that > > sk_can_busy_loop(sock->sk) can't change while an opened file is there. > > And lift that (conditional on new

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Al Viro
On Fri, Jun 22, 2018 at 02:07:39PM +0200, Christoph Hellwig wrote: > On Fri, Jun 22, 2018 at 12:56:13PM +0100, Al Viro wrote: > > So mark that in ->f_mode - I strongly suspect that > > sk_can_busy_loop(sock->sk) can't change while an opened file is there. > > And lift that (conditional on new

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Christoph Hellwig
On Fri, Jun 22, 2018 at 12:56:13PM +0100, Al Viro wrote: > So mark that in ->f_mode - I strongly suspect that > sk_can_busy_loop(sock->sk) can't change while an opened file is there. > And lift that (conditional on new FMODE_BUSY_LOOP) into do_poll() > and do_select() - we *already* have

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Christoph Hellwig
On Fri, Jun 22, 2018 at 12:56:13PM +0100, Al Viro wrote: > So mark that in ->f_mode - I strongly suspect that > sk_can_busy_loop(sock->sk) can't change while an opened file is there. > And lift that (conditional on new FMODE_BUSY_LOOP) into do_poll() > and do_select() - we *already* have

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Al Viro
On Fri, Jun 22, 2018 at 01:53:00PM +0200, Christoph Hellwig wrote: > > Now, ->sk_wq is modified only in sock_init_data() and sock_graft(); > > the latter, IIRC, is ->accept() helper. Do we ever call either of > > those on a sock of already opened file? IOW, is there any real > > reason for

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Al Viro
On Fri, Jun 22, 2018 at 01:53:00PM +0200, Christoph Hellwig wrote: > > Now, ->sk_wq is modified only in sock_init_data() and sock_graft(); > > the latter, IIRC, is ->accept() helper. Do we ever call either of > > those on a sock of already opened file? IOW, is there any real > > reason for

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Christoph Hellwig
On Fri, Jun 22, 2018 at 12:01:17PM +0100, Al Viro wrote: > For fuck sake, if you want vfs_poll() inlined, *make* *it* *inlined*. That is not going to help with de-virtualizing _qproc, which was the whole idea of that change. At least not without a compiler way smarter than gcc. But if you want

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Christoph Hellwig
On Fri, Jun 22, 2018 at 12:01:17PM +0100, Al Viro wrote: > For fuck sake, if you want vfs_poll() inlined, *make* *it* *inlined*. That is not going to help with de-virtualizing _qproc, which was the whole idea of that change. At least not without a compiler way smarter than gcc. But if you want

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Al Viro
On Fri, Jun 22, 2018 at 12:00:14PM +0200, Christoph Hellwig wrote: > And a version with select() also covered: For fuck sake, if you want vfs_poll() inlined, *make* *it* *inlined*. Is there any reason for not doing that other than EXPORT_SYMBOL_GPL fetish? Because if there isn't, I would like to

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Al Viro
On Fri, Jun 22, 2018 at 12:00:14PM +0200, Christoph Hellwig wrote: > And a version with select() also covered: For fuck sake, if you want vfs_poll() inlined, *make* *it* *inlined*. Is there any reason for not doing that other than EXPORT_SYMBOL_GPL fetish? Because if there isn't, I would like to

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Linus Torvalds
On Fri, Jun 22, 2018 at 7:02 PM Linus Torvalds wrote: > > Get your act together. Don't uglify and slow down everything else just > because you're concentrating only on aio. .. and seriously, poll and select are timing-critical. There are many real loads where they show up as *the* thing in

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Linus Torvalds
On Fri, Jun 22, 2018 at 7:02 PM Linus Torvalds wrote: > > Get your act together. Don't uglify and slow down everything else just > because you're concentrating only on aio. .. and seriously, poll and select are timing-critical. There are many real loads where they show up as *the* thing in

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Linus Torvalds
On Fri, Jun 22, 2018 at 6:46 PM Christoph Hellwig wrote: > > > The disadvantages are obvious: every poll event now causes *two* > > indirect branches to the low-level filesystem or driver - one to get > > he poll head, and one to get the mask. Add to that all the new "do we > > have the new-style

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Linus Torvalds
On Fri, Jun 22, 2018 at 6:46 PM Christoph Hellwig wrote: > > > The disadvantages are obvious: every poll event now causes *two* > > indirect branches to the low-level filesystem or driver - one to get > > he poll head, and one to get the mask. Add to that all the new "do we > > have the new-style

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Christoph Hellwig
And a version with select() also covered: --- >From 317159003ae28113cf759c632b161fb39192fe3c Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 22 Jun 2018 11:36:26 +0200 Subject: fs: optimize away ->_qproc indirection for poll_mask based polling Signed-off-by: Christoph Hellwig ---

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Christoph Hellwig
And a version with select() also covered: --- >From 317159003ae28113cf759c632b161fb39192fe3c Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 22 Jun 2018 11:36:26 +0200 Subject: fs: optimize away ->_qproc indirection for poll_mask based polling Signed-off-by: Christoph Hellwig ---

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Christoph Hellwig
On Fri, Jun 22, 2018 at 06:25:45PM +0900, Linus Torvalds wrote: > What was the alleged advantage of the new poll methods again? Because > it sure isn't obvious - not from the numbers, and not from the commit > messages. The primary goal is that we can implement a race-free aio poll, the primary

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Christoph Hellwig
On Fri, Jun 22, 2018 at 06:25:45PM +0900, Linus Torvalds wrote: > What was the alleged advantage of the new poll methods again? Because > it sure isn't obvious - not from the numbers, and not from the commit > messages. The primary goal is that we can implement a race-free aio poll, the primary

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Linus Torvalds
[ Added Al, since this all came in through his trees. The guilty authors were already added by the robot ] On Fri, Jun 22, 2018 at 5:31 PM kernel test robot wrote: > > FYI, we noticed a -8.8% regression of will-it-scale.per_process_ops due to > commit: Guys, this seems pretty big. What was

Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression

2018-06-22 Thread Linus Torvalds
[ Added Al, since this all came in through his trees. The guilty authors were already added by the robot ] On Fri, Jun 22, 2018 at 5:31 PM kernel test robot wrote: > > FYI, we noticed a -8.8% regression of will-it-scale.per_process_ops due to > commit: Guys, this seems pretty big. What was