Use common code for enabling tracing via xenmon and xentrace, also fixing

the last two remaining xc_private.h users outside of libxc.

Signed-off-by: John Levon <john.levon@sun.com>

tools/libxc/xc_tbuf.c

@@ -16,7 +16,7 @@
 
 #include "xc_private.h"
 
-int xc_tbuf_enable(int xc_handle, int enable)
+static int tbuf_enable(int xc_handle, int enable)
 {
   DECLARE_DOM0_OP;
 
@@ -30,7 +30,7 @@ int xc_tbuf_enable(int xc_handle, int enable)
   return xc_dom0_op(xc_handle, &op);
 }
 
-int xc_tbuf_set_size(int xc_handle, uint32_t size)
+int xc_tbuf_set_size(int xc_handle, unsigned long size)
 {
   DECLARE_DOM0_OP;
 
@@ -42,7 +42,7 @@ int xc_tbuf_set_size(int xc_handle, uint32_t size)
   return xc_dom0_op(xc_handle, &op);
 }
 
-int xc_tbuf_get_size(int xc_handle, uint32_t *size)
+int xc_tbuf_get_size(int xc_handle, unsigned long *size)
 {
   int rc;
   DECLARE_DOM0_OP;
@@ -57,10 +57,17 @@ int xc_tbuf_get_size(int xc_handle, uint32_t *size)
   return rc;
 }
 
-int xc_tbuf_get_mfn(int xc_handle, unsigned long *mfn)
+int xc_tbuf_enable(int xc_handle, size_t cnt, unsigned long *mfn,
+    unsigned long *size)
 {
-    int rc;
     DECLARE_DOM0_OP;
+    int rc;
+
+    if ( xc_tbuf_set_size(xc_handle, cnt) != 0 )
+        return -1;
+
+    if ( tbuf_enable(xc_handle, 1) != 0 )
+        return -1;
 
     op.cmd = DOM0_TBUFCONTROL;
     op.interface_version = DOM0_INTERFACE_VERSION;
@@ -68,8 +75,17 @@ int xc_tbuf_get_mfn(int xc_handle, unsigned long *mfn)
 
     rc = xc_dom0_op(xc_handle, &op);
     if ( rc == 0 )
-      *mfn = op.u.tbufcontrol.buffer_mfn;
-    return rc;
+    {
+        *size = op.u.tbufcontrol.size;
+        *mfn = op.u.tbufcontrol.buffer_mfn;
+    }
+
+    return 0;
+}
+
+int xc_tbuf_disable(int xc_handle)
+{
+    return tbuf_enable(xc_handle, 0);
 }
 
 int xc_tbuf_set_cpu_mask(int xc_handle, uint32_t mask)
@@ -95,3 +111,4 @@ int xc_tbuf_set_evt_mask(int xc_handle, uint32_t mask)
 
     return do_dom0_op(xc_handle, &op);
 }
+

tools/libxc/xenctrl.h

@@ -529,15 +529,23 @@ long xc_get_tot_pages(int xc_handle, uint32_t domid);
  */
 
 /**
- * This function enables or disables tracing. Trace buffer memory must
- * be already allocated by setting the size to a non-zero value, otherwise
- * tracing cannot be enabled.
+ * xc_tbuf_enable - enable tracing buffers
  *
  * @parm xc_handle a handle to an open hypervisor interface
- * @parm enable the desired action, 1 for enable, 0 for disable
- * @return 0 on success, -1 on failure.
+ * @parm cnt size of tracing buffers to create (in pages)
+ * @parm mfn location to store mfn of the trace buffers to
+ * @parm size location to store the size (in bytes) of a trace buffer to
+ *
+ * Gets the machine address of the trace pointer area and the size of the
+ * per CPU buffers.
  */
-int xc_tbuf_enable(int xc_handle, int enable);
+int xc_tbuf_enable(int xc_handle, size_t cnt, unsigned long *mfn,
+    unsigned long *size);
+
+/*
+ * Disable tracing buffers.
+ */
+int xc_tbuf_disable(int xc_handle);
 
 /**
  * This function sets the size of the trace buffers. Setting the size
@@ -549,7 +557,7 @@ int xc_tbuf_enable(int xc_handle, int enable);
  * @parm size the size in pages per cpu for the trace buffers
  * @return 0 on success, -1 on failure.
  */
-int xc_tbuf_set_size(int xc_handle, uint32_t size);
+int xc_tbuf_set_size(int xc_handle, unsigned long size);
 
 /**
  * This function retrieves the current size of the trace buffers.
@@ -559,16 +567,7 @@ int xc_tbuf_set_size(int xc_handle, uint32_t size);
  * @parm size will contain the size in bytes for the trace buffers
  * @return 0 on success, -1 on failure.
  */
-int xc_tbuf_get_size(int xc_handle, uint32_t *size);
-
-/**
- * This function retrieves the machine frame of the trace buffer.
-
- * @parm xc_handle a handle to an open hypervisor interface
- * @parm mfn will contain the machine frame of the buffer.
- * @return 0 on success, -1 on failure.
- */
-int xc_tbuf_get_mfn(int xc_handle, unsigned long *mfn);
+int xc_tbuf_get_size(int xc_handle, unsigned long *size);
 
 int xc_tbuf_set_cpu_mask(int xc_handle, uint32_t mask);
 

tools/xenmon/xenbaked.c

@@ -35,6 +35,7 @@
 #include <sys/mman.h>
 #include <sys/stat.h>
 #include <sys/types.h>
+#include <sys/ioctl.h>
 #include <fcntl.h>
 #include <unistd.h>
 #include <errno.h>
@@ -46,7 +47,14 @@
 #include <sys/select.h>
 #include <xen/linux/evtchn.h>
 
-#include "xc_private.h"
+#define PERROR(_m, _a...)                                       \
+do {                                                            \
+    int __saved_errno = errno;                                  \
+    fprintf(stderr, "ERROR: " _m " (%d = %s)\n" , ## _a ,       \
+            __saved_errno, strerror(__saved_errno));            \
+    errno = __saved_errno;                                      \
+} while (0)
+
 typedef struct { int counter; } atomic_t;
 #define _atomic_read(v)		((v).counter)
 
@@ -326,79 +334,34 @@ void wait_for_event(void)
   }
 }
 
-void enable_tracing_or_die(int xc_handle) 
+static void get_tbufs(unsigned long *mfn, unsigned long *size)
 {
-  int enable = 1;
-  int tbsize = DEFAULT_TBUF_SIZE;
-  
-  if (xc_tbuf_enable(xc_handle, enable) != 0) {
-    if (xc_tbuf_set_size(xc_handle, tbsize) != 0) {
-      perror("set_size Hypercall failure");
-      exit(1);
+    int xc_handle = xc_interface_open();
+    int ret;
+
+    if ( xc_handle < 0 ) 
+    {
+        exit(EXIT_FAILURE);
     }
-    printf("Set default trace buffer allocation (%d pages)\n", tbsize);
-    if (xc_tbuf_enable(xc_handle, enable) != 0) {
-      perror("Could not enable trace buffers\n");
-      exit(1);
+
+    ret = xc_tbuf_enable(xc_handle, DEFAULT_TBUF_SIZE, mfn, size);
+
+    if ( ret != 0 )
+    {
+        perror("Couldn't enable trace buffers");
+        exit(1);
     }
-  }
-  else
-    printf("Tracing enabled\n");
+
+    xc_interface_close(xc_handle);
 }
 
 void disable_tracing(void)
 {
-  int enable = 0;
   int xc_handle = xc_interface_open();
-    
-  xc_tbuf_enable(xc_handle, enable);
+  xc_tbuf_disable(xc_handle);  
   xc_interface_close(xc_handle);
 }
 
-
-/**
- * get_tbufs - get pointer to and size of the trace buffers
- * @mfn:  location to store mfn of the trace buffers to
- * @size: location to store the size of a trace buffer to
- *
- * Gets the machine address of the trace pointer area and the size of the
- * per CPU buffers.
- */
-void get_tbufs(unsigned long *mfn, unsigned long *size)
-{
-    int ret;
-    dom0_op_t op;                        /* dom0 op we'll build             */
-    int xc_handle = xc_interface_open(); /* for accessing control interface */
-    unsigned int tbsize;
-
-    enable_tracing_or_die(xc_handle);
-
-    if (xc_tbuf_get_size(xc_handle, &tbsize) != 0) {
-      perror("Failure to get tbuf info from Xen. Guess size is 0?");
-      exit(1);
-    }
-    else
-      printf("Current tbuf size: 0x%x\n", tbsize);
-    
-
-    op.cmd = DOM0_TBUFCONTROL;
-    op.interface_version = DOM0_INTERFACE_VERSION;
-    op.u.tbufcontrol.op  = DOM0_TBUF_GET_INFO;
-
-    ret = do_dom0_op(xc_handle, &op);
-
-    xc_interface_close(xc_handle);
-
-    if ( ret != 0 )
-    {
-        PERROR("Failure to get trace buffer pointer from Xen");
-        exit(EXIT_FAILURE);
-    }
-
-    *mfn  = op.u.tbufcontrol.buffer_mfn;
-    *size = op.u.tbufcontrol.size;
-}
-
 /**
  * map_tbufs - memory map Xen trace buffers into user space
  * @tbufs_mfn: mfn of the trace buffers

tools/xentrace/xentrace.c

@@ -28,8 +28,6 @@
 
 #include <xenctrl.h>
 
-#include "xc_private.h"
-
 #define PERROR(_m, _a...)                                       \
 do {                                                            \
     int __saved_errno = errno;                                  \
@@ -103,67 +101,25 @@ void write_rec(unsigned int cpu, struct t_rec *rec, FILE *out)
     }
 }
 
-void enable_tracing_or_die(int xc_handle) 
-{
-  int enable = 1;
-  int tbsize = DEFAULT_TBUF_SIZE;
-  
-  if (xc_tbuf_enable(xc_handle, enable) != 0) {
-    if (xc_tbuf_set_size(xc_handle, tbsize) != 0) {
-      perror("set_size Hypercall failure");
-      exit(1);
-    }
-    printf("Set default trace buffer allocation (%d pages)\n", tbsize);
-    if (xc_tbuf_enable(xc_handle, enable) != 0) {
-      perror("Could not enable trace buffers\n");
-      exit(1);
-    }
-  }
-  else
-    printf("Tracing enabled\n");
-}
-
-/**
- * get_tbufs - get pointer to and size of the trace buffers
- * @mfn:  location to store mfn of the trace buffers to
- * @size: location to store the size of a trace buffer to
- *
- * Gets the machine address of the trace pointer area and the size of the
- * per CPU buffers.
- */
-void get_tbufs(unsigned long *mfn, unsigned long *size)
+static void get_tbufs(unsigned long *mfn, unsigned long *size)
 {
+    int xc_handle = xc_interface_open();
     int ret;
-    dom0_op_t op;                        /* dom0 op we'll build             */
-    int xc_handle = xc_interface_open(); /* for accessing control interface */
-    unsigned int tbsize;
 
-    enable_tracing_or_die(xc_handle);
-
-    if (xc_tbuf_get_size(xc_handle, &tbsize) != 0) {
-      perror("Failure to get tbuf info from Xen. Guess size is 0?");
-      exit(1);
-    }
-    else
-      printf("Current tbuf size: 0x%x\n", tbsize);
-    
-
-    op.cmd = DOM0_TBUFCONTROL;
-    op.interface_version = DOM0_INTERFACE_VERSION;
-    op.u.tbufcontrol.op  = DOM0_TBUF_GET_INFO;
-
-    ret = do_dom0_op(xc_handle, &op);
-
-    xc_interface_close(xc_handle);
-
-    if ( ret != 0 )
+    if ( xc_handle < 0 ) 
     {
-        PERROR("Failure to get trace buffer pointer from Xen");
         exit(EXIT_FAILURE);
     }
 
-    *mfn  = op.u.tbufcontrol.buffer_mfn;
-    *size = op.u.tbufcontrol.size;
+    ret = xc_tbuf_enable(xc_handle, DEFAULT_TBUF_SIZE, mfn, size);
+
+    if ( ret != 0 )
+    {
+        perror("Couldn't enable trace buffers");
+        exit(1);
+    }
+
+    xc_interface_close(xc_handle);
 }
 
 /**