search for: __get_user_pages_fast

...) > - goto err; > - > - err = -ENOMEM; > - map = kmalloc(sizeof(*map), GFP_ATOMIC); > - if (!map) > - goto err; > - > - pages = kmalloc_array(npages, sizeof(struct page *), GFP_ATOMIC); > - if (!pages) > - goto err_pages; > - > - err = EFAULT; > - npinned = __get_user_pages_fast(uaddr->uaddr, npages, > - uaddr->write, pages); > - if (npinned > 0) > - release_pages(pages, npinned); > - if (npinned != npages) > - goto err_gup; > - > - for (i = 0; i < npinned; i++) > - if (PageHighMem(pages[i])) > - goto err_gup; > - > - v...

Hi: Per request from Michael and Jason, the metadata accelreation is reverted in this version and rework in next version. Please review. Thanks Jason Wang (2): Revert "vhost: access vq metadata through kernel virtual address" vhost: re-introducing metadata acceleration through kernel virtual address drivers/vhost/vhost.c | 202 +++++++++++++++++++++++++-----------------

Hi: Per request from Michael and Jason, the metadata accelreation is reverted in this version and rework in next version. Please review. Thanks Jason Wang (2): Revert "vhost: access vq metadata through kernel virtual address" vhost: re-introducing metadata acceleration through kernel virtual address drivers/vhost/vhost.c | 202 +++++++++++++++++++++++++-----------------

...) > + goto err; > + > + err = -ENOMEM; > + map = kmalloc(sizeof(*map), GFP_ATOMIC); > + if (!map) > + goto err; > + > + pages = kmalloc_array(npages, sizeof(struct page *), GFP_ATOMIC); > + if (!pages) > + goto err_pages; > + > + err = EFAULT; > + npinned = __get_user_pages_fast(uaddr->uaddr, npages, > + uaddr->write, pages); > + if (npinned > 0) > + release_pages(pages, npinned); > + if (npinned != npages) > + goto err_gup; > + > + for (i = 0; i < npinned; i++) > + if (PageHighMem(pages[i])) > + goto err_gup; > + > + v...

...) > + goto err; > + > + err = -ENOMEM; > + map = kmalloc(sizeof(*map), GFP_ATOMIC); > + if (!map) > + goto err; > + > + pages = kmalloc_array(npages, sizeof(struct page *), GFP_ATOMIC); > + if (!pages) > + goto err_pages; > + > + err = EFAULT; > + npinned = __get_user_pages_fast(uaddr->uaddr, npages, > + uaddr->write, pages); > + if (npinned > 0) > + release_pages(pages, npinned); > + if (npinned != npages) > + goto err_gup; > + > + for (i = 0; i < npinned; i++) > + if (PageHighMem(pages[i])) > + goto err_gup; > + > + v...

...q->mmu_lock); - - err = -EFAULT; - if (vq->invalidate_count) - goto err; - - err = -ENOMEM; - map = kmalloc(sizeof(*map), GFP_ATOMIC); - if (!map) - goto err; - - pages = kmalloc_array(npages, sizeof(struct page *), GFP_ATOMIC); - if (!pages) - goto err_pages; - - err = EFAULT; - npinned = __get_user_pages_fast(uaddr->uaddr, npages, - uaddr->write, pages); - if (npinned > 0) - release_pages(pages, npinned); - if (npinned != npages) - goto err_gup; - - for (i = 0; i < npinned; i++) - if (PageHighMem(pages[i])) - goto err_gup; - - vaddr = v = page_address(pages[0]); - - /* For simplicit...

...-ENOMEM; >> + map = kmalloc(sizeof(*map), GFP_ATOMIC); >> + if (!map) >> + goto err; >> + >> + pages = kmalloc_array(npages, sizeof(struct page *), GFP_ATOMIC); >> + if (!pages) >> + goto err_pages; >> + >> + err = EFAULT; >> + npinned = __get_user_pages_fast(uaddr->uaddr, npages, >> + uaddr->write, pages); >> + if (npinned > 0) >> + release_pages(pages, npinned); >> + if (npinned != npages) >> + goto err_gup; >> + >> + for (i = 0; i < npinned; i++) >> + if (PageHighMem(pages[i])) >&g...

...OMIC); > > > + if (!map) > > > + goto err; > > > + > > > + pages = kmalloc_array(npages, sizeof(struct page *), GFP_ATOMIC); > > > + if (!pages) > > > + goto err_pages; > > > + > > > + err = EFAULT; > > > + npinned = __get_user_pages_fast(uaddr->uaddr, npages, > > > + uaddr->write, pages); > > > + if (npinned > 0) > > > + release_pages(pages, npinned); > > > + if (npinned != npages) > > > + goto err_gup; > > > + > > > + for (i = 0; i < npinned; i++) &gt...

...q->mmu_lock); + + err = -EFAULT; + if (vq->invalidate_count) + goto err; + + err = -ENOMEM; + map = kmalloc(sizeof(*map), GFP_ATOMIC); + if (!map) + goto err; + + pages = kmalloc_array(npages, sizeof(struct page *), GFP_ATOMIC); + if (!pages) + goto err_pages; + + err = EFAULT; + npinned = __get_user_pages_fast(uaddr->uaddr, npages, + uaddr->write, pages); + if (npinned > 0) + release_pages(pages, npinned); + if (npinned != npages) + goto err_gup; + + for (i = 0; i < npinned; i++) + if (PageHighMem(pages[i])) + goto err_gup; + + vaddr = v = page_address(pages[0]); + + /* For simplicit...

This series tries to access virtqueue metadata through kernel virtual address instead of copy_user() friends since they had too much overheads like checks, spec barriers or even hardware feature toggling. This is done through setup kernel address through direct mapping and co-opreate VM management with MMU notifiers. Test shows about 23% improvement on TX PPS. TCP_STREAM doesn't see obvious

Hi: This series tries to access virtqueue metadata through kernel virtual address instead of copy_user() friends since they had too much overheads like checks, spec barriers or even hardware feature toggling like SMAP. This is done through setup kernel address through direct mapping and co-opreate VM management with MMU notifiers. Test shows about 23% improvement on TX PPS. TCP_STREAM

Hi: This series tries to access virtqueue metadata through kernel virtual address instead of copy_user() friends since they had too much overheads like checks, spec barriers or even hardware feature toggling like SMAP. This is done through setup kernel address through direct mapping and co-opreate VM management with MMU notifiers. Test shows about 23% improvement on TX PPS. TCP_STREAM

...+ spin_unlock(&tdb->lock); + + target_db_put(tdb); + + return result; +} + +/* Last resort call if memory of client got unmapped before ioctl(REM_UNMAP) */ +static bool not_mapped_in_client(struct page_db *pdb) +{ + int numpages; + struct page *req_page; + bool result = false; + + numpages = __get_user_pages_fast(pdb->map_hva, 1, 0, &req_page); + if (numpages == 0) + return true; + + /* page was munmapped & replaced by a normal page */ + if (!PageRemote(req_page)) + result = true; + + put_page(req_page); + return result; +} + +/* + * Clear all the links to a target at once. + */ +static void mm...

The KVM introspection subsystem provides a facility for applications running on the host or in a separate VM, to control the execution of other VM-s (pause, resume, shutdown), query the state of the vCPUs (GPRs, MSRs etc.), alter the page access bits in the shadow page tables (only for the hardware backed ones, eg. Intel's EPT) and receive notifications when events of interest have taken place

The KVM introspection subsystem provides a facility for applications running on the host or in a separate VM, to control the execution of other VM-s (pause, resume, shutdown), query the state of the vCPUs (GPRs, MSRs etc.), alter the page access bits in the shadow page tables (only for the hardware backed ones, eg. Intel's EPT) and receive notifications when events of interest have taken place