[v2 01/11] vmx: add new boot parameter to control PML enabling

[Kai Huang <kai.huang@linux.intel.com>]

A top level EPT parameter "ept=<options>" and a sub boolean "opt_pml_enabled"
are added to control PML. Other booleans can be further added for any other EPT
related features.

Signed-off-by: Kai Huang <kai.huang@linux.intel.com>
---
 xen/arch/x86/hvm/vmx/vmcs.c | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/xen/arch/x86/hvm/vmx/vmcs.c b/xen/arch/x86/hvm/vmx/vmcs.c
index d614638..4fff46d 100644
--- a/xen/arch/x86/hvm/vmx/vmcs.c
+++ b/xen/arch/x86/hvm/vmx/vmcs.c
@@ -64,6 +64,37 @@ integer_param("ple_gap", ple_gap);
 static unsigned int __read_mostly ple_window = 4096;
 integer_param("ple_window", ple_window);
 
+static bool_t __read_mostly opt_pml_enabled = 0;
+
+/*
+ * The 'ept' parameter controls functionalities that depend on, or impact the
+ * EPT mechanism. Optional comma separated value may contain:
+ *
+ *  pml                 Enable PML
+ */
+static void __init parse_ept_param(char *s)
+{
+    char *ss;
+    int val;
+
+    do {
+        val = !!strncmp(s, "no-", 3);
+        if ( !val )
+            s += 3;
+
+        ss = strchr(s, ',');
+        if ( ss )
+            *ss = '\0';
+
+        if ( !strcmp(s, "pml") )
+            opt_pml_enabled = val;
+
+        s = ss + 1;
+    } while ( ss );
+}
+
+custom_param("ept", parse_ept_param);
+
 /* Dynamic (run-time adjusted) execution control flags. */
 u32 vmx_pin_based_exec_control __read_mostly;
 u32 vmx_cpu_based_exec_control __read_mostly;
-- 
2.1.0