On 11/06/2018 09:49, Song, HaiyanX wrote: > Hi Laurent, > > Regression test for v11 patch serials have been run, some regression is found by LKP-tools (linux kernel performance) > tested on Intel 4s skylake platform. This time only test the cases which have been run and found regressions on > V9 patch serials. > > The regression result is sorted by the metric will-it-scale.per_thread_ops. > branch: Laurent-Dufour/Speculative-page-faults/20180520-045126 > commit id: > head commit : a7a8993bfe3ccb54ad468b9f1799649e4ad1ff12 > base commit : ba98a1cdad71d259a194461b3a61471b49b14df1 > Benchmark: will-it-scale > Download link: https://github.com/antonblanchard/will-it-scale/tree/master > > Metrics: > will-it-scale.per_process_ops=processes/nr_cpu > will-it-scale.per_thread_ops=threads/nr_cpu > test box: lkp-skl-4sp1(nr_cpu=192,memory=768G) > THP: enable / disable > nr_task:100% > > 1. Regressions: > > a). Enable THP > testcase base change head metric > page_fault3/enable THP 10519 -20.5% 836 will-it-scale.per_thread_ops > page_fault2/enalbe THP 8281 -18.8% 6728 will-it-scale.per_thread_ops > brk1/eanble THP 998475 -2.2% 976893 will-it-scale.per_process_ops > context_switch1/enable THP 223910 -1.3% 220930 will-it-scale.per_process_ops > context_switch1/enable THP 233722 -1.0% 231288 will-it-scale.per_thread_ops > > b). Disable THP > page_fault3/disable THP 10856 -23.1% 8344 will-it-scale.per_thread_ops > page_fault2/disable THP 8147 -18.8% 6613 will-it-scale.per_thread_ops > brk1/disable THP 957 -7.9% 881 will-it-scale.per_thread_ops > context_switch1/disable THP 237006 -2.2% 231907 will-it-scale.per_thread_ops > brk1/disable THP 997317 -2.0% 977778 will-it-scale.per_process_ops > page_fault3/disable THP 467454 -1.8% 459251 will-it-scale.per_process_ops > context_switch1/disable THP 224431 -1.3% 221567 will-it-scale.per_process_ops > > Notes: for the above values of test result, the higher is better. I tried the same tests on my PowerPC victim VM (1024 CPUs, 11TB) and I can't get reproducible results. The results have huge variation, even on the vanilla kernel, and I can't state on any changes due to that. I tried on smaller node (80 CPUs, 32G), and the tests ran better, but I didn't measure any changes between the vanilla and the SPF patched ones: test THP enabled 4.17.0-rc4-mm1 spf delta page_fault3_threads 2697.7 2683.5 -0.53% page_fault2_threads 170660.6 169574.1 -0.64% context_switch1_threads 6915269.2 6877507.3 -0.55% context_switch1_processes 6478076.2 6529493.5 0.79% brk1 243391.2 238527.5 -2.00% Tests were run 10 times, no high variation detected. Did you see high variation on your side ? How many times the test were run to compute the average values ? Thanks, Laurent. > > 2. Improvement: not found improvement based on the selected test cases. > > > Best regards > Haiyan Song > ________________________________________ > From: owner-linux-mm@xxxxxxxxx [owner-linux-mm@xxxxxxxxx] on behalf of Laurent Dufour [ldufour@xxxxxxxxxxxxxxxxxx] > Sent: Monday, May 28, 2018 4:54 PM > To: Song, HaiyanX > Cc: akpm@xxxxxxxxxxxxxxxxxxxx; mhocko@xxxxxxxxxx; peterz@xxxxxxxxxxxxx; kirill@xxxxxxxxxxxxx; ak@xxxxxxxxxxxxxxx; dave@xxxxxxxxxxxx; jack@xxxxxxx; Matthew Wilcox; khandual@xxxxxxxxxxxxxxxxxx; aneesh.kumar@xxxxxxxxxxxxxxxxxx; benh@xxxxxxxxxxxxxxxxxxx; mpe@xxxxxxxxxxxxxx; paulus@xxxxxxxxx; Thomas Gleixner; Ingo Molnar; hpa@xxxxxxxxx; Will Deacon; Sergey Senozhatsky; sergey.senozhatsky.work@xxxxxxxxx; Andrea Arcangeli; Alexei Starovoitov; Wang, Kemi; Daniel Jordan; David Rientjes; Jerome Glisse; Ganesh Mahendran; Minchan Kim; Punit Agrawal; vinayak menon; Yang Shi; linux-kernel@xxxxxxxxxxxxxxx; linux-mm@xxxxxxxxx; haren@xxxxxxxxxxxxxxxxxx; npiggin@xxxxxxxxx; bsingharora@xxxxxxxxx; paulmck@xxxxxxxxxxxxxxxxxx; Tim Chen; linuxppc-dev@xxxxxxxxxxxxxxxx; x86@xxxxxxxxxx > Subject: Re: [PATCH v11 00/26] Speculative page faults > > On 28/05/2018 10:22, Haiyan Song wrote: >> Hi Laurent, >> >> Yes, these tests are done on V9 patch. > > Do you plan to give this V11 a run ? > >> >> >> Best regards, >> Haiyan Song >> >> On Mon, May 28, 2018 at 09:51:34AM +0200, Laurent Dufour wrote: >>> On 28/05/2018 07:23, Song, HaiyanX wrote: >>>> >>>> Some regression and improvements is found by LKP-tools(linux kernel performance) on V9 patch series >>>> tested on Intel 4s Skylake platform. >>> >>> Hi, >>> >>> Thanks for reporting this benchmark results, but you mentioned the "V9 patch >>> series" while responding to the v11 header series... >>> Were these tests done on v9 or v11 ? >>> >>> Cheers, >>> Laurent. >>> >>>> >>>> The regression result is sorted by the metric will-it-scale.per_thread_ops. >>>> Branch: Laurent-Dufour/Speculative-page-faults/20180316-151833 (V9 patch series) >>>> Commit id: >>>> base commit: d55f34411b1b126429a823d06c3124c16283231f >>>> head commit: 0355322b3577eeab7669066df42c550a56801110 >>>> Benchmark suite: will-it-scale >>>> Download link: >>>> https://github.com/antonblanchard/will-it-scale/tree/master/tests >>>> Metrics: >>>> will-it-scale.per_process_ops=processes/nr_cpu >>>> will-it-scale.per_thread_ops=threads/nr_cpu >>>> test box: lkp-skl-4sp1(nr_cpu=192,memory=768G) >>>> THP: enable / disable >>>> nr_task: 100% >>>> >>>> 1. Regressions: >>>> a) THP enabled: >>>> testcase base change head metric >>>> page_fault3/ enable THP 10092 -17.5% 8323 will-it-scale.per_thread_ops >>>> page_fault2/ enable THP 8300 -17.2% 6869 will-it-scale.per_thread_ops >>>> brk1/ enable THP 957.67 -7.6% 885 will-it-scale.per_thread_ops >>>> page_fault3/ enable THP 172821 -5.3% 163692 will-it-scale.per_process_ops >>>> signal1/ enable THP 9125 -3.2% 8834 will-it-scale.per_process_ops >>>> >>>> b) THP disabled: >>>> testcase base change head metric >>>> page_fault3/ disable THP 10107 -19.1% 8180 will-it-scale.per_thread_ops >>>> page_fault2/ disable THP 8432 -17.8% 6931 will-it-scale.per_thread_ops >>>> context_switch1/ disable THP 215389 -6.8% 200776 will-it-scale.per_thread_ops >>>> brk1/ disable THP 939.67 -6.6% 877.33 will-it-scale.per_thread_ops >>>> page_fault3/ disable THP 173145 -4.7% 165064 will-it-scale.per_process_ops >>>> signal1/ disable THP 9162 -3.9% 8802 will-it-scale.per_process_ops >>>> >>>> 2. Improvements: >>>> a) THP enabled: >>>> testcase base change head metric >>>> malloc1/ enable THP 66.33 +469.8% 383.67 will-it-scale.per_thread_ops >>>> writeseek3/ enable THP 2531 +4.5% 2646 will-it-scale.per_thread_ops >>>> signal1/ enable THP 989.33 +2.8% 1016 will-it-scale.per_thread_ops >>>> >>>> b) THP disabled: >>>> testcase base change head metric >>>> malloc1/ disable THP 90.33 +417.3% 467.33 will-it-scale.per_thread_ops >>>> read2/ disable THP 58934 +39.2% 82060 will-it-scale.per_thread_ops >>>> page_fault1/ disable THP 8607 +36.4% 11736 will-it-scale.per_thread_ops >>>> read1/ disable THP 314063 +12.7% 353934 will-it-scale.per_thread_ops >>>> writeseek3/ disable THP 2452 +12.5% 2759 will-it-scale.per_thread_ops >>>> signal1/ disable THP 971.33 +5.5% 1024 will-it-scale.per_thread_ops >>>> >>>> Notes: for above values in column "change", the higher value means that the related testcase result >>>> on head commit is better than that on base commit for this benchmark. >>>> >>>> >>>> Best regards >>>> Haiyan Song >>>> >>>> ________________________________________ >>>> From: owner-linux-mm@xxxxxxxxx [owner-linux-mm@xxxxxxxxx] on behalf of Laurent Dufour [ldufour@xxxxxxxxxxxxxxxxxx] >>>> Sent: Thursday, May 17, 2018 7:06 PM >>>> To: akpm@xxxxxxxxxxxxxxxxxxxx; mhocko@xxxxxxxxxx; peterz@xxxxxxxxxxxxx; kirill@xxxxxxxxxxxxx; ak@xxxxxxxxxxxxxxx; dave@xxxxxxxxxxxx; jack@xxxxxxx; Matthew Wilcox; khandual@xxxxxxxxxxxxxxxxxx; aneesh.kumar@xxxxxxxxxxxxxxxxxx; benh@xxxxxxxxxxxxxxxxxxx; mpe@xxxxxxxxxxxxxx; paulus@xxxxxxxxx; Thomas Gleixner; Ingo Molnar; hpa@xxxxxxxxx; Will Deacon; Sergey Senozhatsky; sergey.senozhatsky.work@xxxxxxxxx; Andrea Arcangeli; Alexei Starovoitov; Wang, Kemi; Daniel Jordan; David Rientjes; Jerome Glisse; Ganesh Mahendran; Minchan Kim; Punit Agrawal; vinayak menon; Yang Shi >>>> Cc: linux-kernel@xxxxxxxxxxxxxxx; linux-mm@xxxxxxxxx; haren@xxxxxxxxxxxxxxxxxx; npiggin@xxxxxxxxx; bsingharora@xxxxxxxxx; paulmck@xxxxxxxxxxxxxxxxxx; Tim Chen; linuxppc-dev@xxxxxxxxxxxxxxxx; x86@xxxxxxxxxx >>>> Subject: [PATCH v11 00/26] Speculative page faults >>>> >>>> This is a port on kernel 4.17 of the work done by Peter Zijlstra to handle >>>> page fault without holding the mm semaphore [1]. >>>> >>>> The idea is to try to handle user space page faults without holding the >>>> mmap_sem. This should allow better concurrency for massively threaded >>>> process since the page fault handler will not wait for other threads memory >>>> layout change to be done, assuming that this change is done in another part >>>> of the process's memory space. This type page fault is named speculative >>>> page fault. If the speculative page fault fails because of a concurrency is >>>> detected or because underlying PMD or PTE tables are not yet allocating, it >>>> is failing its processing and a classic page fault is then tried. >>>> >>>> The speculative page fault (SPF) has to look for the VMA matching the fault >>>> address without holding the mmap_sem, this is done by introducing a rwlock >>>> which protects the access to the mm_rb tree. Previously this was done using >>>> SRCU but it was introducing a lot of scheduling to process the VMA's >>>> freeing operation which was hitting the performance by 20% as reported by >>>> Kemi Wang [2]. Using a rwlock to protect access to the mm_rb tree is >>>> limiting the locking contention to these operations which are expected to >>>> be in a O(log n) order. In addition to ensure that the VMA is not freed in >>>> our back a reference count is added and 2 services (get_vma() and >>>> put_vma()) are introduced to handle the reference count. Once a VMA is >>>> fetched from the RB tree using get_vma(), it must be later freed using >>>> put_vma(). I can't see anymore the overhead I got while will-it-scale >>>> benchmark anymore. >>>> >>>> The VMA's attributes checked during the speculative page fault processing >>>> have to be protected against parallel changes. This is done by using a per >>>> VMA sequence lock. This sequence lock allows the speculative page fault >>>> handler to fast check for parallel changes in progress and to abort the >>>> speculative page fault in that case. >>>> >>>> Once the VMA has been found, the speculative page fault handler would check >>>> for the VMA's attributes to verify that the page fault has to be handled >>>> correctly or not. Thus, the VMA is protected through a sequence lock which >>>> allows fast detection of concurrent VMA changes. If such a change is >>>> detected, the speculative page fault is aborted and a *classic* page fault >>>> is tried. VMA sequence lockings are added when VMA attributes which are >>>> checked during the page fault are modified. >>>> >>>> When the PTE is fetched, the VMA is checked to see if it has been changed, >>>> so once the page table is locked, the VMA is valid, so any other changes >>>> leading to touching this PTE will need to lock the page table, so no >>>> parallel change is possible at this time. >>>> >>>> The locking of the PTE is done with interrupts disabled, this allows >>>> checking for the PMD to ensure that there is not an ongoing collapsing >>>> operation. Since khugepaged is firstly set the PMD to pmd_none and then is >>>> waiting for the other CPU to have caught the IPI interrupt, if the pmd is >>>> valid at the time the PTE is locked, we have the guarantee that the >>>> collapsing operation will have to wait on the PTE lock to move forward. >>>> This allows the SPF handler to map the PTE safely. If the PMD value is >>>> different from the one recorded at the beginning of the SPF operation, the >>>> classic page fault handler will be called to handle the operation while >>>> holding the mmap_sem. As the PTE lock is done with the interrupts disabled, >>>> the lock is done using spin_trylock() to avoid dead lock when handling a >>>> page fault while a TLB invalidate is requested by another CPU holding the >>>> PTE. >>>> >>>> In pseudo code, this could be seen as: >>>> speculative_page_fault() >>>> { >>>> vma = get_vma() >>>> check vma sequence count >>>> check vma's support >>>> disable interrupt >>>> check pgd,p4d,...,pte >>>> save pmd and pte in vmf >>>> save vma sequence counter in vmf >>>> enable interrupt >>>> check vma sequence count >>>> handle_pte_fault(vma) >>>> .. >>>> page = alloc_page() >>>> pte_map_lock() >>>> disable interrupt >>>> abort if sequence counter has changed >>>> abort if pmd or pte has changed >>>> pte map and lock >>>> enable interrupt >>>> if abort >>>> free page >>>> abort >>>> ... >>>> } >>>> >>>> arch_fault_handler() >>>> { >>>> if (speculative_page_fault(&vma)) >>>> goto done >>>> again: >>>> lock(mmap_sem) >>>> vma = find_vma(); >>>> handle_pte_fault(vma); >>>> if retry >>>> unlock(mmap_sem) >>>> goto again; >>>> done: >>>> handle fault error >>>> } >>>> >>>> Support for THP is not done because when checking for the PMD, we can be >>>> confused by an in progress collapsing operation done by khugepaged. The >>>> issue is that pmd_none() could be true either if the PMD is not already >>>> populated or if the underlying PTE are in the way to be collapsed. So we >>>> cannot safely allocate a PMD if pmd_none() is true. >>>> >>>> This series add a new software performance event named 'speculative-faults' >>>> or 'spf'. It counts the number of successful page fault event handled >>>> speculatively. When recording 'faults,spf' events, the faults one is >>>> counting the total number of page fault events while 'spf' is only counting >>>> the part of the faults processed speculatively. >>>> >>>> There are some trace events introduced by this series. They allow >>>> identifying why the page faults were not processed speculatively. This >>>> doesn't take in account the faults generated by a monothreaded process >>>> which directly processed while holding the mmap_sem. This trace events are >>>> grouped in a system named 'pagefault', they are: >>>> - pagefault:spf_vma_changed : if the VMA has been changed in our back >>>> - pagefault:spf_vma_noanon : the vma->anon_vma field was not yet set. >>>> - pagefault:spf_vma_notsup : the VMA's type is not supported >>>> - pagefault:spf_vma_access : the VMA's access right are not respected >>>> - pagefault:spf_pmd_changed : the upper PMD pointer has changed in our >>>> back. >>>> >>>> To record all the related events, the easier is to run perf with the >>>> following arguments : >>>> $ perf stat -e 'faults,spf,pagefault:*' <command> >>>> >>>> There is also a dedicated vmstat counter showing the number of successful >>>> page fault handled speculatively. I can be seen this way: >>>> $ grep speculative_pgfault /proc/vmstat >>>> >>>> This series builds on top of v4.16-mmotm-2018-04-13-17-28 and is functional >>>> on x86, PowerPC and arm64. >>>> >>>> --------------------- >>>> Real Workload results >>>> >>>> As mentioned in previous email, we did non official runs using a "popular >>>> in memory multithreaded database product" on 176 cores SMT8 Power system >>>> which showed a 30% improvements in the number of transaction processed per >>>> second. This run has been done on the v6 series, but changes introduced in >>>> this new version should not impact the performance boost seen. >>>> >>>> Here are the perf data captured during 2 of these runs on top of the v8 >>>> series: >>>> vanilla spf >>>> faults 89.418 101.364 +13% >>>> spf n/a 97.989 >>>> >>>> With the SPF kernel, most of the page fault were processed in a speculative >>>> way. >>>> >>>> Ganesh Mahendran had backported the series on top of a 4.9 kernel and gave >>>> it a try on an android device. He reported that the application launch time >>>> was improved in average by 6%, and for large applications (~100 threads) by >>>> 20%. >>>> >>>> Here are the launch time Ganesh mesured on Android 8.0 on top of a Qcom >>>> MSM845 (8 cores) with 6GB (the less is better): >>>> >>>> Application 4.9 4.9+spf delta >>>> com.tencent.mm 416 389 -7% >>>> com.eg.android.AlipayGphone 1135 986 -13% >>>> com.tencent.mtt 455 454 0% >>>> com.qqgame.hlddz 1497 1409 -6% >>>> com.autonavi.minimap 711 701 -1% >>>> com.tencent.tmgp.sgame 788 748 -5% >>>> com.immomo.momo 501 487 -3% >>>> com.tencent.peng 2145 2112 -2% >>>> com.smile.gifmaker 491 461 -6% >>>> com.baidu.BaiduMap 479 366 -23% >>>> com.taobao.taobao 1341 1198 -11% >>>> com.baidu.searchbox 333 314 -6% >>>> com.tencent.mobileqq 394 384 -3% >>>> com.sina.weibo 907 906 0% >>>> com.youku.phone 816 731 -11% >>>> com.happyelements.AndroidAnimal.qq 763 717 -6% >>>> com.UCMobile 415 411 -1% >>>> com.tencent.tmgp.ak 1464 1431 -2% >>>> com.tencent.qqmusic 336 329 -2% >>>> com.sankuai.meituan 1661 1302 -22% >>>> com.netease.cloudmusic 1193 1200 1% >>>> air.tv.douyu.android 4257 4152 -2% >>>> >>>> ------------------ >>>> Benchmarks results >>>> >>>> Base kernel is v4.17.0-rc4-mm1 >>>> SPF is BASE + this series >>>> >>>> Kernbench: >>>> ---------- >>>> Here are the results on a 16 CPUs X86 guest using kernbench on a 4.15 >>>> kernel (kernel is build 5 times): >>>> >>>> Average Half load -j 8 >>>> Run (std deviation) >>>> BASE SPF >>>> Elapsed Time 1448.65 (5.72312) 1455.84 (4.84951) 0.50% >>>> User Time 10135.4 (30.3699) 10148.8 (31.1252) 0.13% >>>> System Time 900.47 (2.81131) 923.28 (7.52779) 2.53% >>>> Percent CPU 761.4 (1.14018) 760.2 (0.447214) -0.16% >>>> Context Switches 85380 (3419.52) 84748 (1904.44) -0.74% >>>> Sleeps 105064 (1240.96) 105074 (337.612) 0.01% >>>> >>>> Average Optimal load -j 16 >>>> Run (std deviation) >>>> BASE SPF >>>> Elapsed Time 920.528 (10.1212) 927.404 (8.91789) 0.75% >>>> User Time 11064.8 (981.142) 11085 (990.897) 0.18% >>>> System Time 979.904 (84.0615) 1001.14 (82.5523) 2.17% >>>> Percent CPU 1089.5 (345.894) 1086.1 (343.545) -0.31% >>>> Context Switches 159488 (78156.4) 158223 (77472.1) -0.79% >>>> Sleeps 110566 (5877.49) 110388 (5617.75) -0.16% >>>> >>>> >>>> During a run on the SPF, perf events were captured: >>>> Performance counter stats for '../kernbench -M': >>>> 526743764 faults >>>> 210 spf >>>> 3 pagefault:spf_vma_changed >>>> 0 pagefault:spf_vma_noanon >>>> 2278 pagefault:spf_vma_notsup >>>> 0 pagefault:spf_vma_access >>>> 0 pagefault:spf_pmd_changed >>>> >>>> Very few speculative page faults were recorded as most of the processes >>>> involved are monothreaded (sounds that on this architecture some threads >>>> were created during the kernel build processing). >>>> >>>> Here are the kerbench results on a 80 CPUs Power8 system: >>>> >>>> Average Half load -j 40 >>>> Run (std deviation) >>>> BASE SPF >>>> Elapsed Time 117.152 (0.774642) 117.166 (0.476057) 0.01% >>>> User Time 4478.52 (24.7688) 4479.76 (9.08555) 0.03% >>>> System Time 131.104 (0.720056) 134.04 (0.708414) 2.24% >>>> Percent CPU 3934 (19.7104) 3937.2 (19.0184) 0.08% >>>> Context Switches 92125.4 (576.787) 92581.6 (198.622) 0.50% >>>> Sleeps 317923 (652.499) 318469 (1255.59) 0.17% >>>> >>>> Average Optimal load -j 80 >>>> Run (std deviation) >>>> BASE SPF >>>> Elapsed Time 107.73 (0.632416) 107.31 (0.584936) -0.39% >>>> User Time 5869.86 (1466.72) 5871.71 (1467.27) 0.03% >>>> System Time 153.728 (23.8573) 157.153 (24.3704) 2.23% >>>> Percent CPU 5418.6 (1565.17) 5436.7 (1580.91) 0.33% >>>> Context Switches 223861 (138865) 225032 (139632) 0.52% >>>> Sleeps 330529 (13495.1) 332001 (14746.2) 0.45% >>>> >>>> During a run on the SPF, perf events were captured: >>>> Performance counter stats for '../kernbench -M': >>>> 116730856 faults >>>> 0 spf >>>> 3 pagefault:spf_vma_changed >>>> 0 pagefault:spf_vma_noanon >>>> 476 pagefault:spf_vma_notsup >>>> 0 pagefault:spf_vma_access >>>> 0 pagefault:spf_pmd_changed >>>> >>>> Most of the processes involved are monothreaded so SPF is not activated but >>>> there is no impact on the performance. >>>> >>>> Ebizzy: >>>> ------- >>>> The test is counting the number of records per second it can manage, the >>>> higher is the best. I run it like this 'ebizzy -mTt <nrcpus>'. To get >>>> consistent result I repeated the test 100 times and measure the average >>>> result. The number is the record processes per second, the higher is the >>>> best. >>>> >>>> BASE SPF delta >>>> 16 CPUs x86 VM 742.57 1490.24 100.69% >>>> 80 CPUs P8 node 13105.4 24174.23 84.46% >>>> >>>> Here are the performance counter read during a run on a 16 CPUs x86 VM: >>>> Performance counter stats for './ebizzy -mTt 16': >>>> 1706379 faults >>>> 1674599 spf >>>> 30588 pagefault:spf_vma_changed >>>> 0 pagefault:spf_vma_noanon >>>> 363 pagefault:spf_vma_notsup >>>> 0 pagefault:spf_vma_access >>>> 0 pagefault:spf_pmd_changed >>>> >>>> And the ones captured during a run on a 80 CPUs Power node: >>>> Performance counter stats for './ebizzy -mTt 80': >>>> 1874773 faults >>>> 1461153 spf >>>> 413293 pagefault:spf_vma_changed >>>> 0 pagefault:spf_vma_noanon >>>> 200 pagefault:spf_vma_notsup >>>> 0 pagefault:spf_vma_access >>>> 0 pagefault:spf_pmd_changed >>>> >>>> In ebizzy's case most of the page fault were handled in a speculative way, >>>> leading the ebizzy performance boost. >>>> >>>> ------------------ >>>> Changes since v10 (https://lkml.org/lkml/2018/4/17/572): >>>> - Accounted for all review feedbacks from Punit Agrawal, Ganesh Mahendran >>>> and Minchan Kim, hopefully. >>>> - Remove unneeded check on CONFIG_SPECULATIVE_PAGE_FAULT in >>>> __do_page_fault(). >>>> - Loop in pte_spinlock() and pte_map_lock() when pte try lock fails >>>> instead >>>> of aborting the speculative page fault handling. Dropping the now >>>> useless >>>> trace event pagefault:spf_pte_lock. >>>> - No more try to reuse the fetched VMA during the speculative page fault >>>> handling when retrying is needed. This adds a lot of complexity and >>>> additional tests done didn't show a significant performance improvement. >>>> - Convert IS_ENABLED(CONFIG_NUMA) back to #ifdef due to build error. >>>> >>>> [1] http://linux-kernel.2935.n7.nabble.com/RFC-PATCH-0-6-Another-go-at-speculative-page-faults-tt965642.html#none >>>> [2] https://patchwork.kernel.org/patch/9999687/ >>>> >>>> >>>> Laurent Dufour (20): >>>> mm: introduce CONFIG_SPECULATIVE_PAGE_FAULT >>>> x86/mm: define ARCH_SUPPORTS_SPECULATIVE_PAGE_FAULT >>>> powerpc/mm: set ARCH_SUPPORTS_SPECULATIVE_PAGE_FAULT >>>> mm: introduce pte_spinlock for FAULT_FLAG_SPECULATIVE >>>> mm: make pte_unmap_same compatible with SPF >>>> mm: introduce INIT_VMA() >>>> mm: protect VMA modifications using VMA sequence count >>>> mm: protect mremap() against SPF hanlder >>>> mm: protect SPF handler against anon_vma changes >>>> mm: cache some VMA fields in the vm_fault structure >>>> mm/migrate: Pass vm_fault pointer to migrate_misplaced_page() >>>> mm: introduce __lru_cache_add_active_or_unevictable >>>> mm: introduce __vm_normal_page() >>>> mm: introduce __page_add_new_anon_rmap() >>>> mm: protect mm_rb tree with a rwlock >>>> mm: adding speculative page fault failure trace events >>>> perf: add a speculative page fault sw event >>>> perf tools: add support for the SPF perf event >>>> mm: add speculative page fault vmstats >>>> powerpc/mm: add speculative page fault >>>> >>>> Mahendran Ganesh (2): >>>> arm64/mm: define ARCH_SUPPORTS_SPECULATIVE_PAGE_FAULT >>>> arm64/mm: add speculative page fault >>>> >>>> Peter Zijlstra (4): >>>> mm: prepare for FAULT_FLAG_SPECULATIVE >>>> mm: VMA sequence count >>>> mm: provide speculative fault infrastructure >>>> x86/mm: add speculative pagefault handling >>>> >>>> arch/arm64/Kconfig | 1 + >>>> arch/arm64/mm/fault.c | 12 + >>>> arch/powerpc/Kconfig | 1 + >>>> arch/powerpc/mm/fault.c | 16 + >>>> arch/x86/Kconfig | 1 + >>>> arch/x86/mm/fault.c | 27 +- >>>> fs/exec.c | 2 +- >>>> fs/proc/task_mmu.c | 5 +- >>>> fs/userfaultfd.c | 17 +- >>>> include/linux/hugetlb_inline.h | 2 +- >>>> include/linux/migrate.h | 4 +- >>>> include/linux/mm.h | 136 +++++++- >>>> include/linux/mm_types.h | 7 + >>>> include/linux/pagemap.h | 4 +- >>>> include/linux/rmap.h | 12 +- >>>> include/linux/swap.h | 10 +- >>>> include/linux/vm_event_item.h | 3 + >>>> include/trace/events/pagefault.h | 80 +++++ >>>> include/uapi/linux/perf_event.h | 1 + >>>> kernel/fork.c | 5 +- >>>> mm/Kconfig | 22 ++ >>>> mm/huge_memory.c | 6 +- >>>> mm/hugetlb.c | 2 + >>>> mm/init-mm.c | 3 + >>>> mm/internal.h | 20 ++ >>>> mm/khugepaged.c | 5 + >>>> mm/madvise.c | 6 +- >>>> mm/memory.c | 612 +++++++++++++++++++++++++++++----- >>>> mm/mempolicy.c | 51 ++- >>>> mm/migrate.c | 6 +- >>>> mm/mlock.c | 13 +- >>>> mm/mmap.c | 229 ++++++++++--- >>>> mm/mprotect.c | 4 +- >>>> mm/mremap.c | 13 + >>>> mm/nommu.c | 2 +- >>>> mm/rmap.c | 5 +- >>>> mm/swap.c | 6 +- >>>> mm/swap_state.c | 8 +- >>>> mm/vmstat.c | 5 +- >>>> tools/include/uapi/linux/perf_event.h | 1 + >>>> tools/perf/util/evsel.c | 1 + >>>> tools/perf/util/parse-events.c | 4 + >>>> tools/perf/util/parse-events.l | 1 + >>>> tools/perf/util/python.c | 1 + >>>> 44 files changed, 1161 insertions(+), 211 deletions(-) >>>> create mode 100644 include/trace/events/pagefault.h >>>> >>>> -- >>>> 2.7.4 >>>> >>>> >>> >> >
