diff options
| -rw-r--r-- | tools/xenpaging/policy.h | 2 | ||||
| -rw-r--r-- | tools/xenpaging/policy_default.c | 9 | ||||
| -rw-r--r-- | tools/xenpaging/xenpaging.c | 99 | ||||
| -rw-r--r-- | tools/xenpaging/xenpaging.h | 10 |
4 files changed, 57 insertions, 63 deletions
diff --git a/tools/xenpaging/policy.h b/tools/xenpaging/policy.h index 905ee7b209..9bb5558c8f 100644 --- a/tools/xenpaging/policy.h +++ b/tools/xenpaging/policy.h @@ -29,7 +29,7 @@ int policy_init(struct xenpaging *paging); -int policy_choose_victim(struct xenpaging *paging, struct victim *victim); +unsigned long policy_choose_victim(struct xenpaging *paging); void policy_notify_paged_out(unsigned long gfn); void policy_notify_paged_in(unsigned long gfn); void policy_notify_paged_in_nomru(unsigned long gfn); diff --git a/tools/xenpaging/policy_default.c b/tools/xenpaging/policy_default.c index c5c71f1b37..596afc7d9a 100644 --- a/tools/xenpaging/policy_default.c +++ b/tools/xenpaging/policy_default.c @@ -77,7 +77,7 @@ int policy_init(struct xenpaging *paging) return rc; } -int policy_choose_victim(struct xenpaging *paging, struct victim *victim) +unsigned long policy_choose_victim(struct xenpaging *paging) { xc_interface *xch = paging->xc_handle; unsigned long wrap = current_gfn; @@ -102,16 +102,13 @@ int policy_choose_victim(struct xenpaging *paging, struct victim *victim) /* One more round before returning ENOSPC */ continue; } - victim->gfn = INVALID_MFN; - return -ENOSPC; + return INVALID_MFN; } } while ( test_bit(current_gfn, bitmap) || test_bit(current_gfn, unconsumed) ); set_bit(current_gfn, unconsumed); - victim->gfn = current_gfn; - - return 0; + return current_gfn; } void policy_notify_paged_out(unsigned long gfn) diff --git a/tools/xenpaging/xenpaging.c b/tools/xenpaging/xenpaging.c index 6f18376b4b..8d07ef0463 100644 --- a/tools/xenpaging/xenpaging.c +++ b/tools/xenpaging/xenpaging.c @@ -430,6 +430,12 @@ static struct xenpaging *xenpaging_init(int argc, char *argv[]) } DPRINTF("max_pages = %d\n", paging->max_pages); + /* Allocate indicies for pagefile slots */ + paging->slot_to_gfn = calloc(paging->max_pages, sizeof(*paging->slot_to_gfn)); + paging->gfn_to_slot = calloc(paging->max_pages, sizeof(*paging->gfn_to_slot)); + if ( !paging->slot_to_gfn || !paging->gfn_to_slot ) + goto err; + /* Initialise policy */ rc = policy_init(paging); if ( rc != 0 ) @@ -468,6 +474,8 @@ static struct xenpaging *xenpaging_init(int argc, char *argv[]) free(dom_path); free(watch_target_tot_pages); + free(paging->slot_to_gfn); + free(paging->gfn_to_slot); free(paging->bitmap); free(paging); } @@ -561,31 +569,29 @@ static void put_response(struct mem_event *mem_event, mem_event_response_t *rsp) RING_PUSH_RESPONSES(back_ring); } -static int xenpaging_evict_page(struct xenpaging *paging, struct victim *victim, int fd, int i) +static int xenpaging_evict_page(struct xenpaging *paging, unsigned long gfn, int fd, int slot) { xc_interface *xch = paging->xc_handle; void *page; - unsigned long gfn; + xen_pfn_t victim = gfn; int ret; DECLARE_DOMCTL; /* Map page */ - gfn = victim->gfn; ret = -EFAULT; - page = xc_map_foreign_pages(xch, paging->mem_event.domain_id, - PROT_READ, &gfn, 1); + page = xc_map_foreign_pages(xch, paging->mem_event.domain_id, PROT_READ, &victim, 1); if ( page == NULL ) { - PERROR("Error mapping page %lx", victim->gfn); + PERROR("Error mapping page %lx", gfn); goto out; } /* Copy page */ - ret = write_page(fd, page, i); + ret = write_page(fd, page, slot); if ( ret != 0 ) { - PERROR("Error copying page %lx", victim->gfn); + PERROR("Error copying page %lx", gfn); munmap(page, PAGE_SIZE); goto out; } @@ -593,17 +599,20 @@ static int xenpaging_evict_page(struct xenpaging *paging, struct victim *victim, munmap(page, PAGE_SIZE); /* Tell Xen to evict page */ - ret = xc_mem_paging_evict(xch, paging->mem_event.domain_id, - victim->gfn); + ret = xc_mem_paging_evict(xch, paging->mem_event.domain_id, gfn); if ( ret != 0 ) { - PERROR("Error evicting page %lx", victim->gfn); + PERROR("Error evicting page %lx", gfn); goto out; } - DPRINTF("evict_page > gfn %lx pageslot %d\n", victim->gfn, i); + DPRINTF("evict_page > gfn %lx pageslot %d\n", gfn, slot); /* Notify policy of page being paged out */ - policy_notify_paged_out(victim->gfn); + policy_notify_paged_out(gfn); + + /* Update index */ + paging->slot_to_gfn[slot] = gfn; + paging->gfn_to_slot[gfn] = slot; /* Record number of evicted pages */ paging->num_paged_out++; @@ -710,19 +719,19 @@ static void resume_pages(struct xenpaging *paging, int num_pages) page_in_trigger(); } -static int evict_victim(struct xenpaging *paging, struct victim *victim, int fd, int i) +static int evict_victim(struct xenpaging *paging, int fd, int slot) { xc_interface *xch = paging->xc_handle; + unsigned long gfn; int j = 0; int ret; do { - ret = policy_choose_victim(paging, victim); - if ( ret != 0 ) + gfn = policy_choose_victim(paging); + if ( gfn == INVALID_MFN ) { - if ( ret != -ENOSPC ) - ERROR("Error choosing victim"); + ret = -ENOSPC; goto out; } @@ -731,9 +740,9 @@ static int evict_victim(struct xenpaging *paging, struct victim *victim, int fd, ret = -EINTR; goto out; } - ret = xc_mem_paging_nominate(xch, paging->mem_event.domain_id, victim->gfn); + ret = xc_mem_paging_nominate(xch, paging->mem_event.domain_id, gfn); if ( ret == 0 ) - ret = xenpaging_evict_page(paging, victim, fd, i); + ret = xenpaging_evict_page(paging, gfn, fd, slot); else { if ( j++ % 1000 == 0 ) @@ -743,7 +752,7 @@ static int evict_victim(struct xenpaging *paging, struct victim *victim, int fd, } while ( ret ); - if ( test_and_set_bit(victim->gfn, paging->bitmap) ) + if ( test_and_set_bit(gfn, paging->bitmap) ) ERROR("Page has been evicted before"); ret = 0; @@ -753,7 +762,7 @@ static int evict_victim(struct xenpaging *paging, struct victim *victim, int fd, } /* Evict a batch of pages and write them to a free slot in the paging file */ -static int evict_pages(struct xenpaging *paging, int fd, struct victim *victims, int num_pages) +static int evict_pages(struct xenpaging *paging, int fd, int num_pages) { xc_interface *xch = paging->xc_handle; int rc, slot, num = 0; @@ -761,10 +770,10 @@ static int evict_pages(struct xenpaging *paging, int fd, struct victim *victims, for ( slot = 0; slot < paging->max_pages && num < num_pages; slot++ ) { /* Slot is allocated */ - if ( victims[slot].gfn != INVALID_MFN ) + if ( paging->slot_to_gfn[slot] ) continue; - rc = evict_victim(paging, &victims[slot], fd, slot); + rc = evict_victim(paging, fd, slot); if ( rc == -ENOSPC ) break; if ( rc == -EINTR ) @@ -780,11 +789,10 @@ int main(int argc, char *argv[]) { struct sigaction act; struct xenpaging *paging; - struct victim *victims; mem_event_request_t req; mem_event_response_t rsp; int num, prev_num = 0; - int i; + int slot; int tot_pages; int rc = -1; int rc1; @@ -813,15 +821,6 @@ int main(int argc, char *argv[]) return 2; } - /* Allocate upper limit of pages to allow growing and shrinking */ - victims = calloc(paging->max_pages, sizeof(struct victim)); - if ( !victims ) - goto out; - - /* Mark all slots as unallocated */ - for ( i = 0; i < paging->max_pages; i++ ) - victims[i].gfn = INVALID_MFN; - /* ensure that if we get a signal, we'll do cleanup, then exit */ act.sa_handler = close_handler; act.sa_flags = 0; @@ -853,32 +852,35 @@ int main(int argc, char *argv[]) { get_request(&paging->mem_event, &req); + if ( req.gfn > paging->max_pages ) + { + ERROR("Requested gfn %"PRIx64" higher than max_pages %lx\n", req.gfn, paging->max_pages); + goto out; + } + /* Check if the page has already been paged in */ if ( test_and_clear_bit(req.gfn, paging->bitmap) ) { /* Find where in the paging file to read from */ - for ( i = 0; i < paging->max_pages; i++ ) - { - if ( victims[i].gfn == req.gfn ) - break; - } - - if ( i >= paging->max_pages ) + slot = paging->gfn_to_slot[req.gfn]; + + /* Sanity check */ + if ( paging->slot_to_gfn[slot] != req.gfn ) { - DPRINTF("Couldn't find page %"PRIx64"\n", req.gfn); + ERROR("Expected gfn %"PRIx64" in slot %d, but found gfn %lx\n", req.gfn, slot, paging->slot_to_gfn[slot]); goto out; } - + if ( req.flags & MEM_EVENT_FLAG_DROP_PAGE ) { - DPRINTF("drop_page ^ gfn %"PRIx64" pageslot %d\n", req.gfn, i); + DPRINTF("drop_page ^ gfn %"PRIx64" pageslot %d\n", req.gfn, slot); /* Notify policy of page being dropped */ policy_notify_dropped(req.gfn); } else { /* Populate the page */ - rc = xenpaging_populate_page(paging, req.gfn, fd, i); + rc = xenpaging_populate_page(paging, req.gfn, fd, slot); if ( rc != 0 ) { PERROR("Error populating page %"PRIx64"", req.gfn); @@ -899,7 +901,7 @@ int main(int argc, char *argv[]) } /* Clear this pagefile slot */ - victims[i].gfn = INVALID_MFN; + paging->slot_to_gfn[slot] = 0; } else { @@ -969,7 +971,7 @@ int main(int argc, char *argv[]) /* Limit the number of evicts to be able to process page-in requests */ if ( num > 42 ) num = 42; - evict_pages(paging, fd, victims, num); + evict_pages(paging, fd, num); } /* Resume some pages if target not reached */ else if ( tot_pages < paging->target_tot_pages && paging->num_paged_out ) @@ -989,7 +991,6 @@ int main(int argc, char *argv[]) out: close(fd); unlink_pagefile(); - free(victims); /* Tear down domain paging */ rc1 = xenpaging_teardown(paging); diff --git a/tools/xenpaging/xenpaging.h b/tools/xenpaging/xenpaging.h index 160fc1d1c5..545f2d3626 100644 --- a/tools/xenpaging/xenpaging.h +++ b/tools/xenpaging/xenpaging.h @@ -46,6 +46,9 @@ struct xenpaging { unsigned long *bitmap; + unsigned long *slot_to_gfn; + int *gfn_to_slot; + struct mem_event mem_event; /* number of pages for which data structures were allocated */ int max_pages; @@ -56,13 +59,6 @@ struct xenpaging { unsigned long pagein_queue[XENPAGING_PAGEIN_QUEUE_SIZE]; }; - -struct victim { - /* the gfn of the page to evict */ - unsigned long gfn; -}; - - extern void create_page_in_thread(struct xenpaging *paging); extern void page_in_trigger(void); |