libxc: simplify performance counters API

Current function has heavily overloaded semantics for the various
arguments. Separate out into more specific functions.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>

diff --git a/tools/libxc/xc_misc.c b/tools/libxc/xc_misc.c
index 47acdb2fb8e5643d60feb2c1a4e7860aaa5bc75a..a64a633e291a40545d6db2907085837b724dddf7 100644 (file)
--- a/tools/libxc/xc_misc.c
+++ b/tools/libxc/xc_misc.c
@@ -167,20 +167,29 @@ int xc_mca_op(xc_interface *xch, struct xen_mc *mc)
 }
 #endif
 
-int xc_perfc_control(xc_interface *xch,
-                     uint32_t opcode,
-                     xc_perfc_desc_t *desc,
-                     xc_perfc_val_t *val,
-                     int *nbr_desc,
-                     int *nbr_val)
+int xc_perfc_reset(xc_interface *xch)
+{
+    DECLARE_SYSCTL;
+
+    sysctl.cmd = XEN_SYSCTL_perfc_op;
+    sysctl.u.perfc_op.cmd = XEN_SYSCTL_PERFCOP_reset;
+    set_xen_guest_handle(sysctl.u.perfc_op.desc, NULL);
+    set_xen_guest_handle(sysctl.u.perfc_op.val, NULL);
+
+    return do_sysctl(xch, &sysctl);
+}
+
+int xc_perfc_query_number(xc_interface *xch,
+                          int *nbr_desc,
+                          int *nbr_val)
 {
     int rc;
     DECLARE_SYSCTL;
 
     sysctl.cmd = XEN_SYSCTL_perfc_op;
-    sysctl.u.perfc_op.cmd = opcode;
-    set_xen_guest_handle(sysctl.u.perfc_op.desc, desc);
-    set_xen_guest_handle(sysctl.u.perfc_op.val, val);
+    sysctl.u.perfc_op.cmd = XEN_SYSCTL_PERFCOP_query;
+    set_xen_guest_handle(sysctl.u.perfc_op.desc, NULL);
+    set_xen_guest_handle(sysctl.u.perfc_op.val, NULL);
 
     rc = do_sysctl(xch, &sysctl);
 
@@ -192,6 +201,20 @@ int xc_perfc_control(xc_interface *xch,
     return rc;
 }
 
+int xc_perfc_query(xc_interface *xch,
+                   xc_perfc_desc_t *desc,
+                   xc_perfc_val_t *val)
+{
+    DECLARE_SYSCTL;
+
+    sysctl.cmd = XEN_SYSCTL_perfc_op;
+    sysctl.u.perfc_op.cmd = XEN_SYSCTL_PERFCOP_query;
+    set_xen_guest_handle(sysctl.u.perfc_op.desc, desc);
+    set_xen_guest_handle(sysctl.u.perfc_op.val, val);
+
+    return do_sysctl(xch, &sysctl);
+}
+
 int xc_lockprof_control(xc_interface *xch,
                         uint32_t opcode,
                         uint32_t *n_elems,

diff --git a/tools/libxc/xenctrl.h b/tools/libxc/xenctrl.h
index e45861f2b31a259ac8b4355fef4ddcea1b006dbc..c004cbc66071635a7309c629a954ef3bfd15b897 100644 (file)
--- a/tools/libxc/xenctrl.h
+++ b/tools/libxc/xenctrl.h
@@ -887,14 +887,15 @@ unsigned long xc_make_page_below_4G(xc_interface *xch, uint32_t domid,
 
 typedef xen_sysctl_perfc_desc_t xc_perfc_desc_t;
 typedef xen_sysctl_perfc_val_t xc_perfc_val_t;
+int xc_perfc_reset(xc_interface *xch);
+int xc_perfc_query_number(xc_interface *xch,
+                          int *nbr_desc,
+                          int *nbr_val);
 /* IMPORTANT: The caller is responsible for mlock()'ing the @desc and @val
    arrays. */
-int xc_perfc_control(xc_interface *xch,
-                     uint32_t op,
-                     xc_perfc_desc_t *desc,
-                     xc_perfc_val_t *val,
-                     int *nbr_desc,
-                     int *nbr_val);
+int xc_perfc_query(xc_interface *xch,
+                   xc_perfc_desc_t *desc,
+                   xc_perfc_val_t *val);
 
 typedef xen_sysctl_lockprof_data_t xc_lockprof_data_t;
 /* IMPORTANT: The caller is responsible for mlock()'ing the @data array. */

diff --git a/tools/misc/xenperf.c b/tools/misc/xenperf.c
index 3730efdbb77621971ed296a3c420452f088ee32e..583abc1f829911a045a8b801182bb1405bd3cec3 100644 (file)
--- a/tools/misc/xenperf.c
+++ b/tools/misc/xenperf.c
@@ -137,8 +137,7 @@ int main(int argc, char *argv[])
     
     if ( reset )
     {
-        if ( xc_perfc_control(xc_handle, XEN_SYSCTL_PERFCOP_reset,
-                              NULL, NULL, NULL, NULL) != 0 )
+        if ( xc_perfc_reset(xc_handle) != 0 )
         {
             fprintf(stderr, "Error reseting performance counters: %d (%s)\n",
                     errno, strerror(errno));
@@ -148,8 +147,7 @@ int main(int argc, char *argv[])
         return 0;
     }
 
-    if ( xc_perfc_control(xc_handle, XEN_SYSCTL_PERFCOP_query,
-                          NULL, NULL, &num_desc, &num_val) != 0 )
+    if ( xc_perfc_query_number(xc_handle, &num_desc, &num_val) != 0 )
     {
         fprintf(stderr, "Error getting number of perf counters: %d (%s)\n",
                 errno, strerror(errno));
@@ -169,8 +167,7 @@ int main(int argc, char *argv[])
         exit(-1);
     }
 
-    if ( xc_perfc_control(xc_handle, XEN_SYSCTL_PERFCOP_query,
-                          pcd, pcv, NULL, NULL) != 0 )
+    if ( xc_perfc_query(xc_handle, pcd, pcv) != 0 )
     {
         fprintf(stderr, "Error getting perf counter: %d (%s)\n",
                 errno, strerror(errno));