x86/vmx: enable PML by default

Since PML series were merged (but disabled by default) we have conducted lots of
PML tests (live migration, GUI display) and PML has been working fine, therefore
turn it on by default.

Document of PML command line is adjusted accordingly as well.

Signed-off-by: Kai Huang <kai.huang@linux.intel.com>
Tested-by: Robert Hu <robert.hu@intel.com>
Tested-by: Xudong Hao <xudong.hao@intel.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Tested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>

diff --git a/docs/misc/xen-command-line.markdown b/docs/misc/xen-command-line.markdown
index c103894e486082678123067edad1044edd3b617f..47d148a2b7f6943194b298093a663139ee32b4bc 100644 (file)
--- a/docs/misc/xen-command-line.markdown
+++ b/docs/misc/xen-command-line.markdown
@@ -715,7 +715,7 @@ Controls EPT related features.
 
 > `pml`
 
-> Default: `false`
+> Default: `true`
 
 >> PML is a new hardware feature in Intel's Broadwell Server and further
 >> platforms which reduces hypervisor overhead of log-dirty mechanism by

diff --git a/xen/arch/x86/hvm/vmx/vmcs.c b/xen/arch/x86/hvm/vmx/vmcs.c
index 7a7896e716a55f9ee21410fc8f72d7b24afb353e..dbf284d9e270edfb0249ab0202ad88ba8f9f677d 100644 (file)
--- a/xen/arch/x86/hvm/vmx/vmcs.c
+++ b/xen/arch/x86/hvm/vmx/vmcs.c
@@ -64,7 +64,7 @@ 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;
+static bool_t __read_mostly opt_pml_enabled = 1;
 static s8 __read_mostly opt_ept_ad = -1;
 
 /*