tools/xenpaging changes

diff -r 335e8273a3f3 -r b80e53a0d6f0 tools/xenpaging/file_ops.c
@@ -1,5 +1,4 @@
 /******************************************************************************
- * tools/xenpaging/file_ops.c
  *
  * Common file operations.
  *

diff -r 335e8273a3f3 -r b80e53a0d6f0 tools/xenpaging/policy_default.c
@@ -1,5 +1,4 @@
 /******************************************************************************
- * tools/xenpaging/policy.c
  *
  * Xen domain paging default policy.
  *

diff -r 335e8273a3f3 -r b80e53a0d6f0 tools/xenpaging/xenpaging.c
@@ -1,5 +1,4 @@
 /******************************************************************************
- * tools/xenpaging/xenpaging.c
  *
  * Domain paging. 
  * Copyright (c) 2009 by Citrix Systems, Inc. (Patrick Colp)

diff -r b80e53a0d6f0 -r 00f6e1294ae2 tools/xenpaging/xenpaging.c
@@ -744,7 +744,6 @@ int main(int argc, char *argv[])
                         !!(req.flags & MEM_EVENT_FLAG_EVICT_FAIL) );
 
                 /* Tell Xen to resume the vcpu */
-                /* XXX: Maybe just check if the vcpu was paused? */
                 if ( req.flags & MEM_EVENT_FLAG_VCPU_PAUSED )
                 {
                     /* Prepare the response */

diff -r 00f6e1294ae2 -r b6c4a6f4f1f7 tools/xenpaging/xenpaging.c
@@ -90,7 +90,7 @@ static int xenpaging_wait_for_event_or_t
         if (errno == EINTR)
             return 0;
 
-        ERROR("Poll exited with an error");
+        PERROR("Poll exited with an error");
         return -errno;
     }
 

@@ -121,7 +121,7 @@ static int xenpaging_wait_for_event_or_t
         port = xc_evtchn_pending(xce);
         if ( port == -1 )
         {
-            ERROR("Failed to read port from event channel");
+            PERROR("Failed to read port from event channel");
             rc = -1;
             goto err;
         }

@@ -129,7 +129,7 @@ static int xenpaging_wait_for_event_or_t
         rc = xc_evtchn_unmask(xce, port);
         if ( rc < 0 )
         {
-            ERROR("Failed to unmask event channel port");
+            PERROR("Failed to unmask event channel port");
         }
     }
 err:

@@ -185,7 +185,7 @@ static xenpaging_t *xenpaging_init(domid
     paging->xs_handle = xs_open(0);
     if ( paging->xs_handle == NULL )
     {
-        ERROR("Error initialising xenstore connection");
+        PERROR("Error initialising xenstore connection");
         goto err;
     }
 

@@ -193,7 +193,7 @@ static xenpaging_t *xenpaging_init(domid
     snprintf(watch_token, sizeof(watch_token), "%u", domain_id);
     if ( xs_watch(paging->xs_handle, "@releaseDomain", watch_token) == false )
     {
-        ERROR("Could not bind to shutdown watch\n");
+        PERROR("Could not bind to shutdown watch\n");
         goto err;
     }
 

@@ -214,7 +214,7 @@ static xenpaging_t *xenpaging_init(domid
     paging->mem_event.shared_page = init_page();
     if ( paging->mem_event.shared_page == NULL )
     {
-        ERROR("Error initialising shared page");
+        PERROR("Error initialising shared page");
         goto err;
     }
 

@@ -222,7 +222,7 @@ static xenpaging_t *xenpaging_init(domid
     paging->mem_event.ring_page = init_page();
     if ( paging->mem_event.ring_page == NULL )
     {
-        ERROR("Error initialising ring page");
+        PERROR("Error initialising ring page");
         goto err;
     }
 

@@ -249,7 +249,7 @@ static xenpaging_t *xenpaging_init(domid
                 ERROR("xenpaging not supported in a PoD guest");
                 break;
             default:
-                ERROR("Error initialising shared page: %s", strerror(errno));
+                PERROR("Error initialising shared page");
                 break;
         }
         goto err;

@@ -259,7 +259,7 @@ static xenpaging_t *xenpaging_init(domid
     paging->mem_event.xce_handle = xc_evtchn_open(NULL, 0);
     if ( paging->mem_event.xce_handle == NULL )
     {
-        ERROR("Failed to open event channel");
+        PERROR("Failed to open event channel");
         goto err;
     }
 

@@ -269,7 +269,7 @@ static xenpaging_t *xenpaging_init(domid
                                     paging->mem_event.shared_page->port);
     if ( rc < 0 )
     {
-        ERROR("Failed to bind event channel");
+        PERROR("Failed to bind event channel");
         goto err;
     }
 

@@ -279,7 +279,7 @@ static xenpaging_t *xenpaging_init(domid
     paging->domain_info = malloc(sizeof(xc_domaininfo_t));
     if ( paging->domain_info == NULL )
     {
-        ERROR("Error allocating memory for domain info");
+        PERROR("Error allocating memory for domain info");
         goto err;
     }
 

@@ -287,7 +287,7 @@ static xenpaging_t *xenpaging_init(domid
                                paging->domain_info);
     if ( rc != 1 )
     {
-        ERROR("Error getting domain info");
+        PERROR("Error getting domain info");
         goto err;
     }
 

@@ -295,7 +295,7 @@ static xenpaging_t *xenpaging_init(domid
     paging->bitmap = bitmap_alloc(paging->domain_info->max_pages);
     if ( !paging->bitmap )
     {
-        ERROR("Error allocating bitmap");
+        PERROR("Error allocating bitmap");
         goto err;
     }
     DPRINTF("max_pages = %"PRIx64"\n", paging->domain_info->max_pages);

@@ -311,7 +311,7 @@ static xenpaging_t *xenpaging_init(domid
     rc = policy_init(paging);
     if ( rc != 0 )
     {
-        ERROR("Error initialising policy");
+        PERROR("Error initialising policy");
         goto err;
     }
 

@@ -358,14 +358,14 @@ static int xenpaging_teardown(xenpaging_
     rc = xc_mem_paging_disable(xch, paging->mem_event.domain_id);
     if ( rc != 0 )
     {
-        ERROR("Error tearing down domain paging in xen");
+        PERROR("Error tearing down domain paging in xen");
     }
 
     /* Unbind VIRQ */
     rc = xc_evtchn_unbind(paging->mem_event.xce_handle, paging->mem_event.port);
     if ( rc != 0 )
     {
-        ERROR("Error unbinding event port");
+        PERROR("Error unbinding event port");
     }
     paging->mem_event.port = -1;
 

@@ -373,7 +373,7 @@ static int xenpaging_teardown(xenpaging_
     rc = xc_evtchn_close(paging->mem_event.xce_handle);
     if ( rc != 0 )
     {
-        ERROR("Error closing event channel");
+        PERROR("Error closing event channel");
     }
     paging->mem_event.xce_handle = NULL;
     

@@ -384,7 +384,7 @@ static int xenpaging_teardown(xenpaging_
     rc = xc_interface_close(xch);
     if ( rc != 0 )
     {
-        ERROR("Error closing connection to xen");
+        PERROR("Error closing connection to xen");
     }
 
     return 0;

@@ -444,7 +444,7 @@ static int xenpaging_evict_page(xenpagin
                                 PROT_READ | PROT_WRITE, &gfn, 1);
     if ( page == NULL )
     {
-        ERROR("Error mapping page");
+        PERROR("Error mapping page");
         goto out;
     }
 

@@ -452,8 +452,8 @@ static int xenpaging_evict_page(xenpagin
     ret = write_page(fd, page, i);
     if ( ret != 0 )
     {
+        PERROR("Error copying page");
         munmap(page, PAGE_SIZE);
-        ERROR("Error copying page");
         goto out;
     }
 

@@ -464,7 +464,7 @@ static int xenpaging_evict_page(xenpagin
                               victim->gfn);
     if ( ret != 0 )
     {
-        ERROR("Error evicting page");
+        PERROR("Error evicting page");
         goto out;
     }
 

@@ -520,7 +520,7 @@ static int xenpaging_populate_page(xenpa
                 sleep(1);
                 continue;
             }
-            ERROR("Error preparing for page in");
+            PERROR("Error preparing for page in");
             goto out_map;
         }
     }

@@ -532,7 +532,7 @@ static int xenpaging_populate_page(xenpa
                                 PROT_READ | PROT_WRITE, &gfn, 1);
     if ( page == NULL )
     {
-        ERROR("Error mapping page: page is null");
+        PERROR("Error mapping page: page is null");
         goto out_map;
     }
 

@@ -540,7 +540,7 @@ static int xenpaging_populate_page(xenpa
     ret = read_page(fd, page, i);
     if ( ret != 0 )
     {
-        ERROR("Error reading page");
+        PERROR("Error reading page");
         goto out;
     }
 

@@ -579,7 +579,7 @@ static int evict_victim(xenpaging_t *pag
         {
             if ( j++ % 1000 == 0 )
                 if ( xenpaging_mem_paging_flush_ioemu_cache(paging) )
-                    ERROR("Error flushing ioemu cache");
+                    PERROR("Error flushing ioemu cache");
         }
     }
     while ( ret );

@@ -670,7 +670,7 @@ int main(int argc, char *argv[])
         rc = xenpaging_wait_for_event_or_timeout(paging);
         if ( rc < 0 )
         {
-            ERROR("Error getting event");
+            PERROR("Error getting event");
             goto out;
         }
         else if ( rc != 0 )

@@ -710,7 +710,7 @@ int main(int argc, char *argv[])
                     rc = xenpaging_populate_page(paging, req.gfn, fd, i);
                     if ( rc != 0 )
                     {
-                        ERROR("Error populating page");
+                        PERROR("Error populating page");
                         goto out;
                     }
                 }

@@ -723,7 +723,7 @@ int main(int argc, char *argv[])
                 rc = xenpaging_resume_page(paging, &rsp, 1);
                 if ( rc != 0 )
                 {
-                    ERROR("Error resuming page");
+                    PERROR("Error resuming page");
                     goto out;
                 }
 

@@ -754,7 +754,7 @@ int main(int argc, char *argv[])
                     rc = xenpaging_resume_page(paging, &rsp, 0);
                     if ( rc != 0 )
                     {
-                        ERROR("Error resuming");
+                        PERROR("Error resuming");
                         goto out;
                     }
                 }

diff -r b6c4a6f4f1f7 -r 0bc6eb35c8bf tools/xenpaging/file_ops.c
@@ -21,55 +21,44 @@
 
 
 #include <unistd.h>
-#include <stdarg.h>
 #include <xc_private.h>
 
-
-#define page_offset(_pfn)     (((off_t)(_pfn)) << PAGE_SHIFT)
-
-
 static int file_op(int fd, void *page, int i,
-                   ssize_t (*fn)(int, const void *, size_t))
+                   ssize_t (*fn)(int, void *, size_t))
 {
     off_t seek_ret;
-    int total;
+    int total = 0;
     int bytes;
-    int ret;
 
     seek_ret = lseek(fd, i << PAGE_SHIFT, SEEK_SET);
+    if ( seek_ret == (off_t)-1 )
+        return -1;
 
-    total = 0;
     while ( total < PAGE_SIZE )
     {
         bytes = fn(fd, page + total, PAGE_SIZE - total);
         if ( bytes <= 0 )
-        {
-            ret = -errno;
-            goto err;
-        }
+            return -1;
 
         total += bytes;
     }
 
     return 0;
-
- err:
-    return ret;
 }
 
-static ssize_t my_read(int fd, const void *buf, size_t count)
+static ssize_t my_write(int fd, void *buf, size_t count)
 {
-    return read(fd, (void *)buf, count);
+    return write(fd, buf, count);
 }
 
 int read_page(int fd, void *page, int i)
 {
-    return file_op(fd, page, i, &my_read);
+    return file_op(fd, page, i, &read);
 }
 
 int write_page(int fd, void *page, int i)
 {
-    return file_op(fd, page, i, &write);
+    return file_op(fd, page, i, &my_write);
 }

diff -r 0bc6eb35c8bf -r c0c01de70558 tools/xenpaging/xenpaging.c
@@ -444,7 +444,7 @@ static int xenpaging_evict_page(xenpagin
                                 PROT_READ | PROT_WRITE, &gfn, 1);
     if ( page == NULL )
     {
-        PERROR("Error mapping page");
+        PERROR("Error mapping page %lx", victim->gfn);
         goto out;
     }
 

@@ -452,7 +452,7 @@ static int xenpaging_evict_page(xenpagin
     ret = write_page(fd, page, i);
     if ( ret != 0 )
     {
-        PERROR("Error copying page");
+        PERROR("Error copying page %lx", victim->gfn);
         munmap(page, PAGE_SIZE);
         goto out;
     }

@@ -464,7 +464,7 @@ static int xenpaging_evict_page(xenpagin
                               victim->gfn);
     if ( ret != 0 )
     {
-        PERROR("Error evicting page");
+        PERROR("Error evicting page %lx", victim->gfn);
         goto out;
     }
 

@@ -520,7 +520,7 @@ static int xenpaging_populate_page(xenpa
                 sleep(1);
                 continue;
             }
-            PERROR("Error preparing for page in");
+            PERROR("Error preparing %"PRI_xen_pfn" for page-in", gfn);
             goto out_map;
         }
     }

@@ -532,7 +532,7 @@ static int xenpaging_populate_page(xenpa
                                 PROT_READ | PROT_WRITE, &gfn, 1);
     if ( page == NULL )
     {
-        PERROR("Error mapping page: page is null");
+        PERROR("Error mapping page %"PRI_xen_pfn": page is null", gfn);
         goto out_map;
     }
 

@@ -540,7 +540,7 @@ static int xenpaging_populate_page(xenpa
     ret = read_page(fd, page, i);
     if ( ret != 0 )
     {
-        PERROR("Error reading page");
+        PERROR("Error reading page %"PRI_xen_pfn"", gfn);
         goto out;
     }
 

@@ -710,7 +710,7 @@ int main(int argc, char *argv[])
                     rc = xenpaging_populate_page(paging, req.gfn, fd, i);
                     if ( rc != 0 )
                     {
-                        PERROR("Error populating page");
+                        PERROR("Error populating page %"PRIx64"", req.gfn);
                         goto out;
                     }
                 }

@@ -723,7 +723,7 @@ int main(int argc, char *argv[])
                 rc = xenpaging_resume_page(paging, &rsp, 1);
                 if ( rc != 0 )
                 {
-                    PERROR("Error resuming page");
+                    PERROR("Error resuming page %"PRIx64"", req.gfn);
                     goto out;
                 }
 

@@ -754,7 +754,7 @@ int main(int argc, char *argv[])
                     rc = xenpaging_resume_page(paging, &rsp, 0);
                     if ( rc != 0 )
                     {
-                        PERROR("Error resuming");
+                        PERROR("Error resuming page %"PRIx64"", req.gfn);
                         goto out;
                     }
                 }

diff -r c0c01de70558 -r 3c4e8b05da8b tools/xenpaging/xenpaging.c
@@ -169,18 +169,21 @@ static xenpaging_t *xenpaging_init(domid
     char *p;
     int rc;
 
+    /* Allocate memory */
+    paging = calloc(1, sizeof(xenpaging_t));
+    if ( !paging )
+        goto err;
+
     if ( getenv("XENPAGING_DEBUG") )
         dbg = (xentoollog_logger *)xtl_createlogger_stdiostream(stderr, XTL_DEBUG, 0);
-    xch = xc_interface_open(dbg, NULL, 0);
+
+    /* Open connection to xen */
+    paging->xc_handle = xch = xc_interface_open(dbg, NULL, 0);
     if ( !xch )
-        goto err_iface;
+        goto err;
 
     DPRINTF("xenpaging init\n");
 
-    /* Allocate memory */
-    paging = malloc(sizeof(xenpaging_t));
-    memset(paging, 0, sizeof(xenpaging_t));
-
     /* Open connection to xenstore */
     paging->xs_handle = xs_open(0);
     if ( paging->xs_handle == NULL )

@@ -204,9 +207,6 @@ static xenpaging_t *xenpaging_init(domid
          DPRINTF("Setting policy mru_size to %d\n", paging->policy_mru_size);
     }
 
-    /* Open connection to xen */
-    paging->xc_handle = xch;
-
     /* Set domain id */
     paging->mem_event.domain_id = domain_id;
 

@@ -322,7 +322,8 @@ static xenpaging_t *xenpaging_init(domid
     {
         if ( paging->xs_handle )
             xs_close(paging->xs_handle);
-        xc_interface_close(xch);
+        if ( xch )
+            xc_interface_close(xch);
         if ( paging->mem_event.shared_page )
         {
             munlock(paging->mem_event.shared_page, PAGE_SIZE);

@@ -340,7 +341,6 @@ static xenpaging_t *xenpaging_init(domid
         free(paging);
     }
 
- err_iface: 
     return NULL;
 }

diff -r 3c4e8b05da8b -r 98c0a058f056 tools/xenpaging/policy_default.c
@@ -41,17 +41,17 @@ int policy_init(xenpaging_t *paging)
     int i;
     int rc = -ENOMEM;
 
+    max_pages = paging->max_pages;
+
     /* Allocate bitmap for pages not to page out */
-    bitmap = bitmap_alloc(paging->domain_info->max_pages);
+    bitmap = bitmap_alloc(max_pages);
     if ( !bitmap )
         goto out;
     /* Allocate bitmap to track unusable pages */
-    unconsumed = bitmap_alloc(paging->domain_info->max_pages);
+    unconsumed = bitmap_alloc(max_pages);
     if ( !unconsumed )
         goto out;
 
-    max_pages = paging->domain_info->max_pages;
-
     /* Initialise MRU list of paged in pages */
     if ( paging->policy_mru_size > 0 )
         mru_size = paging->policy_mru_size;

diff -r 3c4e8b05da8b -r 98c0a058f056 tools/xenpaging/xenpaging.c
@@ -164,6 +164,7 @@ static void *init_page(void)
 static xenpaging_t *xenpaging_init(domid_t domain_id, int num_pages)
 {
     xenpaging_t *paging;
+    xc_domaininfo_t domain_info;
     xc_interface *xch;
     xentoollog_logger *dbg = NULL;
     char *p;

@@ -275,34 +276,29 @@ static xenpaging_t *xenpaging_init(domid
 
     paging->mem_event.port = rc;
 
-    /* Get domaininfo */
-    paging->domain_info = malloc(sizeof(xc_domaininfo_t));
-    if ( paging->domain_info == NULL )
-    {
-        PERROR("Error allocating memory for domain info");
-        goto err;
-    }
-
     rc = xc_domain_getinfolist(xch, paging->mem_event.domain_id, 1,
-                               paging->domain_info);
+                               &domain_info);
     if ( rc != 1 )
     {
         PERROR("Error getting domain info");
         goto err;
     }
 
+    /* Record number of max_pages */
+    paging->max_pages = domain_info.max_pages;
+
     /* Allocate bitmap for tracking pages that have been paged out */
-    paging->bitmap = bitmap_alloc(paging->domain_info->max_pages);
+    paging->bitmap = bitmap_alloc(paging->max_pages);
     if ( !paging->bitmap )
     {
         PERROR("Error allocating bitmap");
         goto err;
     }
-    DPRINTF("max_pages = %"PRIx64"\n", paging->domain_info->max_pages);
+    DPRINTF("max_pages = %d\n", paging->max_pages);
 
-    if ( num_pages < 0 || num_pages > paging->domain_info->max_pages )
+    if ( num_pages < 0 || num_pages > paging->max_pages )
     {
-        num_pages = paging->domain_info->max_pages;
+        num_pages = paging->max_pages;
         DPRINTF("setting num_pages to %d\n", num_pages);
     }
     paging->num_pages = num_pages;

@@ -337,7 +333,6 @@ static xenpaging_t *xenpaging_init(domid
         }
 
         free(paging->bitmap);
-        free(paging->domain_info);
         free(paging);
     }
 

@@ -765,7 +760,7 @@ int main(int argc, char *argv[])
         if ( interrupted == SIGTERM || interrupted == SIGINT )
         {
             int num = 0;
-            for ( i = 0; i < paging->domain_info->max_pages; i++ )
+            for ( i = 0; i < paging->max_pages; i++ )
             {
                 if ( test_bit(i, paging->bitmap) )
                 {

@@ -781,7 +776,7 @@ int main(int argc, char *argv[])
              */
             if ( num )
                 page_in_trigger();
-            else if ( i == paging->domain_info->max_pages )
+            else if ( i == paging->max_pages )
                 break;
         }
         else

diff -r 3c4e8b05da8b -r 98c0a058f056 tools/xenpaging/xenpaging.h
@@ -44,11 +44,11 @@ typedef struct xenpaging {
     xc_interface *xc_handle;
     struct xs_handle *xs_handle;
 
-    xc_domaininfo_t    *domain_info;
-
     unsigned long *bitmap;
 
     mem_event_t mem_event;
+    /* number of pages for which data structures were allocated */
+    int max_pages;
     int num_pages;
     int policy_mru_size;
     unsigned long pagein_queue[XENPAGING_PAGEIN_QUEUE_SIZE];

diff -r 98c0a058f056 -r 927af61e2c89 tools/xenpaging/xenpaging.c
@@ -467,6 +467,9 @@ static int xenpaging_evict_page(xenpagin
     /* Notify policy of page being paged out */
     policy_notify_paged_out(victim->gfn);
 
+    /* Record number of evicted pages */
+    paging->num_paged_out++;
+
  out:
     return ret;
 }

@@ -480,8 +483,13 @@ static int xenpaging_resume_page(xenpagi
 
     /* Notify policy of page being paged in */
     if ( notify_policy )
+    {
         policy_notify_paged_in(rsp->gfn);
 
+       /* Record number of resumed pages */
+       paging->num_paged_out--;
+    }
+
     /* Tell Xen page is ready */
     ret = xc_mem_paging_resume(paging->xc_handle, paging->mem_event.domain_id,
                                rsp->gfn);

diff -r 98c0a058f056 -r 927af61e2c89 tools/xenpaging/xenpaging.h
@@ -49,6 +49,7 @@ typedef struct xenpaging {
     mem_event_t mem_event;
     /* number of pages for which data structures were allocated */
     int max_pages;
+    int num_paged_out;
     int num_pages;
     int policy_mru_size;
     unsigned long pagein_queue[XENPAGING_PAGEIN_QUEUE_SIZE];

diff -r 927af61e2c89 -r 35a65cd961e7 tools/xenpaging/xenpaging.c
@@ -553,6 +553,27 @@ static int xenpaging_populate_page(xenpa
     return ret;
 }
 
+/* Trigger a page-in for a batch of pages */
+static void resume_pages(xenpaging_t *paging, int num_pages)
+{
+    xc_interface *xch = paging->xc_handle;
+    int i, num = 0;
+
+    for ( i = 0; i < paging->max_pages && num < num_pages; i++ )
+    {
+        if ( test_bit(i, paging->bitmap) )
+        {
+            paging->pagein_queue[num] = i;
+            num++;
+            if ( num == XENPAGING_PAGEIN_QUEUE_SIZE )
+                break;
+        }
+    }
+    /* num may be less than num_pages, caller has to try again */
+    if ( num )
+        page_in_trigger();
+}
+
 static int evict_victim(xenpaging_t *paging,
                         xenpaging_victim_t *victim, int fd, int i)
 {

@@ -596,6 +617,30 @@ static int evict_victim(xenpaging_t *pag
     return ret;
 }
 
+/* Evict a batch of pages and write them to a free slot in the paging file */
+static int evict_pages(xenpaging_t *paging, int fd, xenpaging_victim_t *victims, int num_pages)
+{
+    xc_interface *xch = paging->xc_handle;
+    int rc, slot, num = 0;
+
+    for ( slot = 0; slot < paging->max_pages && num < num_pages; slot++ )
+    {
+        /* Slot is allocated */
+        if ( victims[slot].gfn != INVALID_MFN )
+            continue;
+
+        rc = evict_victim(paging, &victims[slot], fd, slot);
+        if ( rc == -ENOSPC )
+            break;
+        if ( rc == -EINTR )
+            break;
+        if ( num && num % 100 == 0 )
+            DPRINTF("%d pages evicted\n", num);
+        num++;
+    }
+    return num;
+}
+
 int main(int argc, char *argv[])
 {
     struct sigaction act;

@@ -638,7 +683,14 @@ int main(int argc, char *argv[])
         return 2;
     }
 
-    victims = calloc(paging->num_pages, sizeof(xenpaging_victim_t));
+    /* Allocate upper limit of pages to allow growing and shrinking */
+    victims = calloc(paging->max_pages, sizeof(xenpaging_victim_t));
+    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;

@@ -652,18 +704,7 @@ int main(int argc, char *argv[])
     /* listen for page-in events to stop pager */
     create_page_in_thread(paging);
 
-    /* Evict pages */
-    for ( i = 0; i < paging->num_pages; i++ )
-    {
-        rc = evict_victim(paging, &victims[i], fd, i);
-        if ( rc == -ENOSPC )
-            break;
-        if ( rc == -EINTR )
-            break;
-        if ( i % 100 == 0 )
-            DPRINTF("%d pages evicted\n", i);
-    }
-
+    i = evict_pages(paging, fd, victims, paging->num_pages);
     DPRINTF("%d pages evicted. Done.\n", i);
 
     /* Swap pages in and out */

@@ -689,13 +730,13 @@ int main(int argc, char *argv[])
             if ( test_and_clear_bit(req.gfn, paging->bitmap) )
             {
                 /* Find where in the paging file to read from */
-                for ( i = 0; i < paging->num_pages; i++ )
+                for ( i = 0; i < paging->max_pages; i++ )
                 {
                     if ( victims[i].gfn == req.gfn )
                         break;
                 }
     
-                if ( i >= paging->num_pages )
+                if ( i >= paging->max_pages )
                 {
                     DPRINTF("Couldn't find page %"PRIx64"\n", req.gfn);
                     goto out;

@@ -767,25 +808,12 @@ int main(int argc, char *argv[])
         /* Write all pages back into the guest */
         if ( interrupted == SIGTERM || interrupted == SIGINT )
         {
-            int num = 0;
-            for ( i = 0; i < paging->max_pages; i++ )
-            {
-                if ( test_bit(i, paging->bitmap) )
-                {
-                    paging->pagein_queue[num] = i;
-                    num++;
-                    if ( num == XENPAGING_PAGEIN_QUEUE_SIZE )
-                        break;
-                }
-            }
-            /*
-             * One more round if there are still pages to process.
-             * If no more pages to process, exit loop.
-             */
-            if ( num )
-                page_in_trigger();
-            else if ( i == paging->max_pages )
+            /* If no more pages to process, exit loop. */
+            if ( !paging->num_paged_out )
                 break;
+            
+            /* One more round if there are still pages to process. */
+            resume_pages(paging, paging->num_paged_out);
         }
         else
         {

diff -r 35a65cd961e7 -r cc72e36fa9c3 tools/xenpaging/xenpaging.c
@@ -805,7 +805,7 @@ int main(int argc, char *argv[])
             }
         }
 
-        /* Write all pages back into the guest */
+        /* If interrupted, write all pages back into the guest */
         if ( interrupted == SIGTERM || interrupted == SIGINT )
         {
             /* If no more pages to process, exit loop. */

@@ -814,13 +814,15 @@ int main(int argc, char *argv[])
             
             /* One more round if there are still pages to process. */
             resume_pages(paging, paging->num_paged_out);
+
+            /* Resume main loop */
+            continue;
         }
-        else
-        {
-            /* Exit on any other signal */
-            if ( interrupted )
-                break;
-        }
+
+        /* Exit main loop on any other signal */
+        if ( interrupted )
+            break;
+
     }
     DPRINTF("xenpaging got signal %d\n", interrupted);

diff -r cc72e36fa9c3 -r e74c938d3851 tools/libxc/xc_bitops.h
@@ -4,6 +4,7 @@
 /* bitmap operations for single threaded access */
 
 #include <stdlib.h>
+#include <string.h>
 
 #define BITS_PER_LONG (sizeof(unsigned long) * 8)
 #define ORDER_LONG (sizeof(unsigned long) == 4 ? 5 : 6)

@@ -25,6 +26,11 @@ static inline unsigned long *bitmap_allo
     return calloc(1, bitmap_size(nr_bits));
 }
 
+static inline void bitmap_clear(unsigned long *addr, int nr_bits)
+{
+    memset(addr, 0, bitmap_size(nr_bits));
+}
+
 static inline int test_bit(int nr, volatile unsigned long *addr)
 {
     return (BITMAP_ENTRY(nr, addr) >> BITMAP_SHIFT(nr)) & 1;

diff -r e74c938d3851 -r 1e343a57860e tools/xenpaging/policy_default.c
@@ -32,6 +32,7 @@ static unsigned int i_mru;
 static unsigned int mru_size;
 static unsigned long *bitmap;
 static unsigned long *unconsumed;
+static unsigned int unconsumed_cleared;
 static unsigned long current_gfn;
 static unsigned long max_pages;
 

@@ -87,8 +88,21 @@ int policy_choose_victim(xenpaging_t *pa
         current_gfn++;
         if ( current_gfn >= max_pages )
             current_gfn = 0;
+        /* Could not nominate any gfn */
         if ( wrap == current_gfn )
         {
+            /* Count wrap arounds */
+            unconsumed_cleared++;
+            /* Force retry every few seconds (depends on poll() timeout) */
+            if ( unconsumed_cleared > 123)
+            {
+                /* Force retry of unconsumed gfns */
+                bitmap_clear(unconsumed, max_pages);
+                unconsumed_cleared = 0;
+                DPRINTF("clearing unconsumed, wrap %lx", wrap);
+                /* One more round before returning ENOSPC */
+                continue;
+            }
             victim->gfn = INVALID_MFN;
             return -ENOSPC;
         }

diff -r 3fe020b22882 -r 303d1521463b tools/libxl/libxl.h
@@ -633,6 +633,7 @@ const char *libxl_xen_config_dir_path(vo
 const char *libxl_xen_script_dir_path(void);
 const char *libxl_lock_dir_path(void);
 const char *libxl_run_dir_path(void);
+const char *libxl_xenpaging_dir_path(void);
 
 #endif /* LIBXL_H */
 

diff -r 3fe020b22882 -r 303d1521463b tools/libxl/libxl_paths.c
@@ -70,6 +70,11 @@ const char *libxl_run_dir_path(void)
     return XEN_RUN_DIR;
 }
 
+const char *libxl_xenpaging_dir_path(void)
+{
+    return XEN_PAGING_DIR;
+}
+
 /*
  * Local variables:
  * mode: C

diff -r 303d1521463b -r 827fcaf0d610 tools/xenpaging/policy_default.c
@@ -71,7 +71,6 @@ int policy_init(xenpaging_t *paging)
 
     /* Start in the middle to avoid paging during BIOS startup */
     current_gfn = max_pages / 2;
-    current_gfn -= paging->num_pages / 2;
 
     rc = 0;
  out:

133 lines not on this page · raw message

diff -r 303d1521463b -r 827fcaf0d610 tools/xenpaging/xenpaging.h
@@ -50,7 +50,7 @@ typedef struct xenpaging {
     /* number of pages for which data structures were allocated */
     int max_pages;
     int num_paged_out;
-    int num_pages;
+    int target_tot_pages;
     int policy_mru_size;
     unsigned long pagein_queue[XENPAGING_PAGEIN_QUEUE_SIZE];
 } xenpaging_t;

diff -r 827fcaf0d610 -r bbe679f21208 tools/xenpaging/xenpaging.c
@@ -19,8 +19,10 @@
  */
 
 #define _XOPEN_SOURCE	600
+#define _GNU_SOURCE
 
 #include <inttypes.h>
+#include <stdio.h>
 #include <stdlib.h>
 #include <stdarg.h>
 #include <time.h>

@@ -35,6 +37,10 @@
 #include "policy.h"
 #include "xenpaging.h"
 
+/* Defines number of mfns a guest should use at a time, in KiB */
+#define WATCH_TARGETPAGES "memory/target-tot_pages"
+static char *watch_target_tot_pages;
+static char *dom_path;
 static char watch_token[16];
 static char filename[80];
 static int interrupted;

@@ -72,7 +78,7 @@ static int xenpaging_wait_for_event_or_t
 {
     xc_interface *xch = paging->xc_handle;
     xc_evtchn *xce = paging->mem_event.xce_handle;
-    char **vec;
+    char **vec, *val;
     unsigned int num;
     struct pollfd fd[2];
     int port;

@@ -111,6 +117,25 @@ static int xenpaging_wait_for_event_or_t
                     rc = 0;
                 }
             }
+            else if ( strcmp(vec[XS_WATCH_PATH], watch_target_tot_pages) == 0 )
+            {
+                int ret, target_tot_pages;
+                val = xs_read(paging->xs_handle, XBT_NULL, vec[XS_WATCH_PATH], NULL);
+                if ( val )
+                {
+                    ret = sscanf(val, "%d", &target_tot_pages);
+                    if ( ret > 0 )
+                    {
+                        /* KiB to pages */
+                        target_tot_pages >>= 2;
+                        if ( target_tot_pages < 0 || target_tot_pages > paging->max_pages )
+                            target_tot_pages = paging->max_pages;
+                        paging->target_tot_pages = target_tot_pages;
+                        DPRINTF("new target_tot_pages %d\n", target_tot_pages);
+                    }
+                    free(val);
+                }
+            }
             free(vec);
         }
     }

@@ -216,6 +241,25 @@ static xenpaging_t *xenpaging_init(domid
         goto err;
     }
 
+    /* Watch xenpagings working target */
+    dom_path = xs_get_domain_path(paging->xs_handle, domain_id);
+    if ( !dom_path )
+    {
+        PERROR("Could not find domain path\n");
+        goto err;
+    }
+    if ( asprintf(&watch_target_tot_pages, "%s/%s", dom_path, WATCH_TARGETPAGES) < 0 )
+    {
+        PERROR("Could not alloc watch path\n");
+        goto err;
+    }
+    DPRINTF("watching '%s'\n", watch_target_tot_pages);
+    if ( xs_watch(paging->xs_handle, watch_target_tot_pages, "") == false )
+    {
+        PERROR("Could not bind to xenpaging watch\n");
+        goto err;
+    }
+
     p = getenv("XENPAGING_POLICY_MRU_SIZE");
     if ( p && *p )
     {

@@ -342,6 +386,8 @@ static xenpaging_t *xenpaging_init(domid
             free(paging->mem_event.ring_page);
         }
 
+        free(dom_path);
+        free(watch_target_tot_pages);
         free(paging->bitmap);
         free(paging);
     }

@@ -357,6 +403,9 @@ static int xenpaging_teardown(xenpaging_
     if ( paging == NULL )
         return 0;
 
+    xs_unwatch(paging->xs_handle, watch_target_tot_pages, "");
+    xs_unwatch(paging->xs_handle, "@releaseDomain", watch_token);
+
     xch = paging->xc_handle;
     paging->xc_handle = NULL;
     /* Tear down domain paging in Xen */

diff -r bbe679f21208 -r deb016f351e5 tools/xenpaging/xenpaging.c
@@ -31,6 +31,7 @@
 #include <poll.h>
 #include <xc_private.h>
 #include <xs.h>
+#include <getopt.h>
 
 #include "xc_bitops.h"
 #include "file_ops.h"

@@ -42,12 +43,12 @@
 static char *watch_target_tot_pages;
 static char *dom_path;
 static char watch_token[16];
-static char filename[80];
+static char *filename;
 static int interrupted;
 
 static void unlink_pagefile(void)
 {
-    if ( filename[0] )
+    if ( filename && filename[0] )
     {
         unlink(filename);
         filename[0] = '\0';

@@ -201,11 +202,85 @@ static void *init_page(void)
     return NULL;
 }
 
-static xenpaging_t *xenpaging_init(domid_t domain_id, int target_tot_pages)
+static void usage(void)
+{
+    printf("usage:\n\n");
+
+    printf("  xenpaging [options] -f <pagefile> -d <domain_id>\n\n");
+
+    printf("options:\n");
+    printf(" -d <domid>     --domain=<domid>         numerical domain_id of guest. This option is required.\n");
+    printf(" -f <file>      --pagefile=<file>        pagefile to use. This option is required.\n");
+    printf(" -m <max_memkb> --max_memkb=<max_memkb>  maximum amount of memory to handle.\n");
+    printf(" -r <num>       --mru_size=<num>         number of paged-in pages to keep in memory.\n");
+    printf(" -v             --verbose                enable debug output.\n");
+    printf(" -h             --help                   this output.\n");
+}
+
+static int xenpaging_getopts(xenpaging_t *paging, int argc, char *argv[])
+{
+    int ch;
+    static const char sopts[] = "hvd:f:m:r:";
+    static const struct option lopts[] = {
+        {"help", 0, NULL, 'h'},
+        {"verbose", 0, NULL, 'v'},
+        {"domain", 1, NULL, 'd'},
+        {"pagefile", 1, NULL, 'f'},
+        {"mru_size", 1, NULL, 'm'},
+        { }
+    };
+
+    while ((ch = getopt_long(argc, argv, sopts, lopts, NULL)) != -1)
+    {
+        switch(ch) {
+        case 'd':
+            paging->mem_event.domain_id = atoi(optarg);
+            break;
+        case 'f':
+            filename = strdup(optarg);
+            break;
+        case 'm':
+            /* KiB to pages */
+            paging->max_pages = atoi(optarg) >> 2;
+            break;
+        case 'r':
+            paging->policy_mru_size = atoi(optarg);
+            break;
+        case 'v':
+            paging->debug = 1;
+            break;
+        case 'h':
+        case '?':
+            usage();
+            return 1;
+        }
+    }
+
+    argv += optind; argc -= optind;
+    
+    /* Path to pagefile is required */
+    if ( !filename )
+    {
+        printf("Filename for pagefile missing!\n");
+        usage();
+        return 1;
+    }
+
+    /* Set domain id */
+    if ( !paging->mem_event.domain_id )
+    {
+        printf("Numerical <domain_id> missing!\n");
+        return 1;
+    }
+
+    return 0;
+}
+
+static xenpaging_t *xenpaging_init(int argc, char *argv[])
 {
     xenpaging_t *paging;
     xc_domaininfo_t domain_info;
-    xc_interface *xch;
+    xc_interface *xch = NULL;
     xentoollog_logger *dbg = NULL;
     char *p;
     int rc;

@@ -215,7 +290,12 @@ static xenpaging_t *xenpaging_init(domid
     if ( !paging )
         goto err;
 
-    if ( getenv("XENPAGING_DEBUG") )
+    /* Get cmdline options and domain_id */
+    if ( xenpaging_getopts(paging, argc, argv) )
+        goto err;
+
+    /* Enable debug output */
+    if ( paging->debug )
         dbg = (xentoollog_logger *)xtl_createlogger_stdiostream(stderr, XTL_DEBUG, 0);
 
     /* Open connection to xen */

@@ -234,7 +314,7 @@ static xenpaging_t *xenpaging_init(domid
     }
 
     /* write domain ID to watch so we can ignore other domain shutdowns */
-    snprintf(watch_token, sizeof(watch_token), "%u", domain_id);
+    snprintf(watch_token, sizeof(watch_token), "%u", paging->mem_event.domain_id);
     if ( xs_watch(paging->xs_handle, "@releaseDomain", watch_token) == false )
     {
         PERROR("Could not bind to shutdown watch\n");

@@ -242,7 +322,7 @@ static xenpaging_t *xenpaging_init(domid
     }
 
     /* Watch xenpagings working target */
-    dom_path = xs_get_domain_path(paging->xs_handle, domain_id);
+    dom_path = xs_get_domain_path(paging->xs_handle, paging->mem_event.domain_id);
     if ( !dom_path )
     {
         PERROR("Could not find domain path\n");

@@ -260,16 +340,6 @@ static xenpaging_t *xenpaging_init(domid
         goto err;
     }
 
-    p = getenv("XENPAGING_POLICY_MRU_SIZE");
-    if ( p && *p )
-    {
-         paging->policy_mru_size = atoi(p);
-         DPRINTF("Setting policy mru_size to %d\n", paging->policy_mru_size);
-    }
-
-    /* Set domain id */
-    paging->mem_event.domain_id = domain_id;
-
     /* Initialise shared page */
     paging->mem_event.shared_page = init_page();
     if ( paging->mem_event.shared_page == NULL )

@@ -335,17 +405,21 @@ static xenpaging_t *xenpaging_init(domid
 
     paging->mem_event.port = rc;
 
-    rc = xc_domain_getinfolist(xch, paging->mem_event.domain_id, 1,
-                               &domain_info);
-    if ( rc != 1 )
+    /* Get max_pages from guest if not provided via cmdline */
+    if ( !paging->max_pages )
     {
-        PERROR("Error getting domain info");
-        goto err;
+        rc = xc_domain_getinfolist(xch, paging->mem_event.domain_id, 1,
+                                   &domain_info);
+        if ( rc != 1 )
+        {
+            PERROR("Error getting domain info");
+            goto err;
+        }
+
+        /* Record number of max_pages */
+        paging->max_pages = domain_info.max_pages;
     }
 
-    /* Record number of max_pages */
-    paging->max_pages = domain_info.max_pages;
-
     /* Allocate bitmap for tracking pages that have been paged out */
     paging->bitmap = bitmap_alloc(paging->max_pages);
     if ( !paging->bitmap )

@@ -355,8 +429,6 @@ static xenpaging_t *xenpaging_init(domid
     }
     DPRINTF("max_pages = %d\n", paging->max_pages);
 
-    paging->target_tot_pages = target_tot_pages;
-
     /* Initialise policy */
     rc = policy_init(paging);
     if ( rc != 0 )

@@ -718,25 +790,18 @@ int main(int argc, char *argv[])
     mode_t open_mode = S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR | S_IWGRP | S_IWOTH;
     int fd;
 
-    if ( argc != 3 )
-    {
-        fprintf(stderr, "Usage: %s <domain_id> <tot_pages>\n", argv[0]);
-        return -1;
-    }
-
     /* Initialise domain paging */
-    paging = xenpaging_init(atoi(argv[1]), atoi(argv[2]));
+    paging = xenpaging_init(argc, argv);
     if ( paging == NULL )
     {
-        fprintf(stderr, "Error initialising paging");
+        fprintf(stderr, "Error initialising paging\n");
         return 1;
     }
     xch = paging->xc_handle;
 
-    DPRINTF("starting %s %u %d\n", argv[0], paging->mem_event.domain_id, paging->target_tot_pages);
+    DPRINTF("starting %s for domain_id %u with pagefile %s\n", argv[0], paging->mem_event.domain_id, filename);
 
     /* Open file */
-    sprintf(filename, "page_cache_%u", paging->mem_event.domain_id);
     fd = open(filename, open_flags, open_mode);
     if ( fd < 0 )
     {

diff -r bbe679f21208 -r deb016f351e5 tools/xenpaging/xenpaging.h
@@ -52,6 +52,7 @@ typedef struct xenpaging {
     int num_paged_out;
     int target_tot_pages;
     int policy_mru_size;
+    int debug;
     unsigned long pagein_queue[XENPAGING_PAGEIN_QUEUE_SIZE];
 } xenpaging_t;

diff -r deb016f351e5 -r ba84a323f2df tools/xenpaging/policy.h
@@ -32,6 +32,8 @@ int policy_init(xenpaging_t *paging);
 int policy_choose_victim(xenpaging_t *paging, xenpaging_victim_t *victim);
 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);
+void policy_notify_dropped(unsigned long gfn);
 
 #endif // __XEN_PAGING_POLICY_H__
 

diff -r deb016f351e5 -r ba84a323f2df tools/xenpaging/policy_default.c
@@ -57,7 +57,7 @@ int policy_init(xenpaging_t *paging)
     if ( paging->policy_mru_size > 0 )
         mru_size = paging->policy_mru_size;
     else
-        mru_size = DEFAULT_MRU_SIZE;
+        mru_size = paging->policy_mru_size = DEFAULT_MRU_SIZE;
 
     mru = malloc(sizeof(*mru) * mru_size);
     if ( mru == NULL )

@@ -120,17 +120,38 @@ void policy_notify_paged_out(unsigned lo
     clear_bit(gfn, unconsumed);
 }
 
-void policy_notify_paged_in(unsigned long gfn)
+static void policy_handle_paged_in(unsigned long gfn, int do_mru)
 {
     unsigned long old_gfn = mru[i_mru & (mru_size - 1)];
 
     if ( old_gfn != INVALID_MFN )
         clear_bit(old_gfn, bitmap);
     
-    mru[i_mru & (mru_size - 1)] = gfn;
+    if (do_mru) {
+        mru[i_mru & (mru_size - 1)] = gfn;
+    } else {
+        clear_bit(gfn, bitmap);
+        mru[i_mru & (mru_size - 1)] = INVALID_MFN;
+    }
+
     i_mru++;
 }
 
+void policy_notify_paged_in(unsigned long gfn)
+{
+    policy_handle_paged_in(gfn, 1);
+}
+
+void policy_notify_paged_in_nomru(unsigned long gfn)
+{
+    policy_handle_paged_in(gfn, 0);
+}
+
+void policy_notify_dropped(unsigned long gfn)
+{
+    clear_bit(gfn, bitmap);
+}
+
 
 /*
  * Local variables:

diff -r deb016f351e5 -r ba84a323f2df tools/xenpaging/xenpaging.c
@@ -615,7 +615,14 @@ static int xenpaging_resume_page(xenpagi
     /* Notify policy of page being paged in */
     if ( notify_policy )
     {
-        policy_notify_paged_in(rsp->gfn);
+        /*
+         * Do not add gfn to mru list if the target is lower than mru size.
+         * This allows page-out of these gfns if the target grows again.
+         */
+        if (paging->num_paged_out > paging->policy_mru_size)
+            policy_notify_paged_in(rsp->gfn);
+        else
+            policy_notify_paged_in_nomru(rsp->gfn);
 
        /* Record number of resumed pages */
        paging->num_paged_out--;

@@ -869,7 +876,7 @@ int main(int argc, char *argv[])
                 {
                     DPRINTF("drop_page ^ gfn %"PRIx64" pageslot %d\n", req.gfn, i);
                     /* Notify policy of page being dropped */
-                    policy_notify_paged_in(req.gfn);
+                    policy_notify_dropped(req.gfn);
                 }
                 else
                 {

diff -r ba84a323f2df -r 47fd37efc373 tools/xenpaging/xenpaging.c
@@ -108,6 +108,7 @@ static int xenpaging_wait_for_event_or_t
         vec = xs_read_watch(paging->xs_handle, &num);
         if ( vec )
         {
+            DPRINTF("path '%s' token '%s'\n", vec[XS_WATCH_PATH], vec[XS_WATCH_TOKEN]);
             if ( strcmp(vec[XS_WATCH_TOKEN], watch_token) == 0 )
             {
                 /* If our guest disappeared, set interrupt flag and fall through */

diff -r 47fd37efc373 -r 9f0156c72538 tools/xenpaging/xenpaging.c
@@ -795,7 +795,7 @@ int main(int argc, char *argv[])
     xc_interface *xch;
 
     int open_flags = O_CREAT | O_TRUNC | O_RDWR;
-    mode_t open_mode = S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR | S_IWGRP | S_IWOTH;
+    mode_t open_mode = S_IRUSR | S_IWUSR;
     int fd;
 
     /* Initialise domain paging */