[PATCH 5/7] tools: Modify single-domid callers of xc_domain_getinfolist

[Alejandro Vallejo <alejandro.vallejo@xxxxxxxxx>]

xc_domain_getinfolist() internally relies on a sysctl that performs
a linear search for the domids. Many callers of xc_domain_getinfolist()
who require information about a precise domid are much better off calling
xc_domain_getinfo_single() instead, that will use the getdomaininfo domctl
instead and ensure the returned domid matches the requested one. The domtctl
will find the domid faster too, because that uses hashed lists.

Signed-off-by: Alejandro Vallejo <alejandro.vallejo@xxxxxxxxx>
---
Cc: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
Cc: Wei Liu <wl@xxxxxxx>
Cc: Anthony PERARD <anthony.perard@xxxxxxxxxx>
Cc: Juergen Gross <jgross@xxxxxxxx>
---
 tools/libs/light/libxl_dom.c         | 15 +++++----------
 tools/libs/light/libxl_dom_suspend.c |  7 +------
 tools/libs/light/libxl_domain.c      | 12 ++++--------
 tools/libs/light/libxl_mem.c         |  4 ++--
 tools/libs/light/libxl_sched.c       | 12 ++++--------
 tools/xenpaging/xenpaging.c          | 14 +++++++-------
 6 files changed, 23 insertions(+), 41 deletions(-)

diff --git a/tools/libs/light/libxl_dom.c b/tools/libs/light/libxl_dom.c
index 25fb716084..482e04b38c 100644
--- a/tools/libs/light/libxl_dom.c
+++ b/tools/libs/light/libxl_dom.c
@@ -32,8 +32,8 @@ libxl_domain_type libxl__domain_type(libxl__gc *gc, uint32_t 
domid)
     xc_domaininfo_t info;
     int ret;
 
-    ret = xc_domain_getinfolist(ctx->xch, domid, 1, &info);
-    if (ret != 1 || info.domain != domid) {
+    ret = xc_domain_getinfo_single(ctx->xch, domid, &info);
+    if (ret < 0) {
         LOG(ERROR, "unable to get domain type for domid=%"PRIu32, domid);
         return LIBXL_DOMAIN_TYPE_INVALID;
     }
@@ -70,15 +70,10 @@ int libxl__domain_cpupool(libxl__gc *gc, uint32_t domid)
     xc_domaininfo_t info;
     int ret;
 
-    ret = xc_domain_getinfolist(CTX->xch, domid, 1, &info);
-    if (ret != 1)
+    ret = xc_domain_getinfo_single(CTX->xch, domid, &info);
+    if (ret < 0)
     {
-        LOGE(ERROR, "getinfolist failed %d", ret);
-        return ERROR_FAIL;
-    }
-    if (info.domain != domid)
-    {
-        LOGE(ERROR, "got info for dom%d, wanted dom%d\n", info.domain, domid);
+        LOGE(ERROR, "getinfo_single failed %d", ret);
         return ERROR_FAIL;
     }
     return info.cpupool;
diff --git a/tools/libs/light/libxl_dom_suspend.c 
b/tools/libs/light/libxl_dom_suspend.c
index 4fa22bb739..6091a5f3f6 100644
--- a/tools/libs/light/libxl_dom_suspend.c
+++ b/tools/libs/light/libxl_dom_suspend.c
@@ -332,13 +332,8 @@ static void suspend_common_wait_guest_check(libxl__egc 
*egc,
     /* Convenience aliases */
     const uint32_t domid = dsps->domid;
 
-    ret = xc_domain_getinfolist(CTX->xch, domid, 1, &info);
+    ret = xc_domain_getinfo_single(CTX->xch, domid, &info);
     if (ret < 0) {
-        LOGED(ERROR, domid, "unable to check for status of guest");
-        goto err;
-    }
-
-    if (!(ret == 1 && info.domain == domid)) {
         LOGED(ERROR, domid, "guest we were suspending has been destroyed");
         goto err;
     }
diff --git a/tools/libs/light/libxl_domain.c b/tools/libs/light/libxl_domain.c
index 7f0986c185..33ac8e9ce8 100644
--- a/tools/libs/light/libxl_domain.c
+++ b/tools/libs/light/libxl_domain.c
@@ -349,16 +349,12 @@ int libxl_domain_info(libxl_ctx *ctx, libxl_dominfo 
*info_r,
     int ret;
     GC_INIT(ctx);
 
-    ret = xc_domain_getinfolist(ctx->xch, domid, 1, &xcinfo);
+    ret = xc_domain_getinfo_single(ctx->xch, domid, &xcinfo);
     if (ret<0) {
-        LOGED(ERROR, domid, "Getting domain info list");
+        LOGED(ERROR, domid, "Getting domain info single");
         GC_FREE;
         return ERROR_FAIL;
     }
-    if (ret==0 || xcinfo.domain != domid) {
-        GC_FREE;
-        return ERROR_DOMAIN_NOTFOUND;
-    }
 
     if (info_r)
         libxl__xcinfo2xlinfo(ctx, &xcinfo, info_r);
@@ -1663,8 +1659,8 @@ libxl_vcpuinfo *libxl_list_vcpu(libxl_ctx *ctx, uint32_t 
domid,
     xc_vcpuinfo_t vcpuinfo;
     unsigned int nr_vcpus;
 
-    if (xc_domain_getinfolist(ctx->xch, domid, 1, &domaininfo) != 1) {
-        LOGED(ERROR, domid, "Getting infolist");
+    if (xc_domain_getinfo_single(ctx->xch, domid, &domaininfo) < 0) {
+        LOGED(ERROR, domid, "Getting info single");
         GC_FREE;
         return NULL;
     }
diff --git a/tools/libs/light/libxl_mem.c b/tools/libs/light/libxl_mem.c
index 92ec09f4cf..44e554adba 100644
--- a/tools/libs/light/libxl_mem.c
+++ b/tools/libs/light/libxl_mem.c
@@ -323,8 +323,8 @@ retry_transaction:
     libxl__xs_printf(gc, t, GCSPRINTF("%s/memory/target", dompath),
                      "%"PRIu64, new_target_memkb);
 
-    r = xc_domain_getinfolist(ctx->xch, domid, 1, &info);
-    if (r != 1 || info.domain != domid) {
+    r = xc_domain_getinfo_single(ctx->xch, domid, &info);
+    if (r < 0) {
         abort_transaction = 1;
         rc = ERROR_FAIL;
         goto out;
diff --git a/tools/libs/light/libxl_sched.c b/tools/libs/light/libxl_sched.c
index 7c53dc60e6..19da7c49ea 100644
--- a/tools/libs/light/libxl_sched.c
+++ b/tools/libs/light/libxl_sched.c
@@ -219,13 +219,11 @@ static int sched_credit_domain_set(libxl__gc *gc, 
uint32_t domid,
     xc_domaininfo_t domaininfo;
     int rc;
 
-    rc = xc_domain_getinfolist(CTX->xch, domid, 1, &domaininfo);
+    rc = xc_domain_getinfo_single(CTX->xch, domid, &domaininfo);
     if (rc < 0) {
-        LOGED(ERROR, domid, "Getting domain info list");
+        LOGED(ERROR, domid, "Getting domain info single");
         return ERROR_FAIL;
     }
-    if (rc != 1 || domaininfo.domain != domid)
-        return ERROR_INVAL;
 
     rc = xc_sched_credit_domain_get(CTX->xch, domid, &sdom);
     if (rc != 0) {
@@ -426,13 +424,11 @@ static int sched_credit2_domain_set(libxl__gc *gc, 
uint32_t domid,
     xc_domaininfo_t info;
     int rc;
 
-    rc = xc_domain_getinfolist(CTX->xch, domid, 1, &info);
+    rc = xc_domain_getinfo_single(CTX->xch, domid, &info);
     if (rc < 0) {
-        LOGED(ERROR, domid, "Getting domain info");
+        LOGED(ERROR, domid, "Getting domain info single");
         return ERROR_FAIL;
     }
-    if (rc != 1 || info.domain != domid)
-        return ERROR_INVAL;
 
     rc = xc_sched_credit2_domain_get(CTX->xch, domid, &sdom);
     if (rc != 0) {
diff --git a/tools/xenpaging/xenpaging.c b/tools/xenpaging/xenpaging.c
index 6e5490315d..023f2bf295 100644
--- a/tools/xenpaging/xenpaging.c
+++ b/tools/xenpaging/xenpaging.c
@@ -169,10 +169,10 @@ static int xenpaging_get_tot_pages(struct xenpaging 
*paging)
     xc_domaininfo_t domain_info;
     int rc;
 
-    rc = xc_domain_getinfolist(xch, paging->vm_event.domain_id, 1, 
&domain_info);
-    if ( rc != 1 )
+    rc = xc_domain_getinfo_single(xch, paging->vm_event.domain_id, 
&domain_info);
+    if ( rc < 0 )
     {
-        PERROR("Error getting domain info");
+        PERROR("Error getting domain info single");
         return -1;
     }
     return domain_info.tot_pages;
@@ -424,11 +424,11 @@ static struct xenpaging *xenpaging_init(int argc, char 
*argv[])
     /* Get max_pages from guest if not provided via cmdline */
     if ( !paging->max_pages )
     {
-        rc = xc_domain_getinfolist(xch, paging->vm_event.domain_id, 1,
-                                   &domain_info);
-        if ( rc != 1 )
+        rc = xc_domain_getinfo_single(xch, paging->vm_event.domain_id,
+                                      &domain_info);
+        if ( rc < 0 )
         {
-            PERROR("Error getting domain info");
+            PERROR("Error getting domain info single");
             goto err;
         }
 
-- 
2.34.1