[PATCH] Doc: admin-guide: Add entry for kvm_cma_resv_ratio kernel param

[sathnaga@linux.vnet.ibm.com]

From: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>

Add document entry for kvm_cma_resv_ratio kernel param which
is used to alter the KVM contiguous memory allocation percentage
for hash pagetable allocation used by hash mode PowerPC KVM guests.

Cc: linux-kernel@vger.kernel.org
Cc: kvm-ppc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Jonathan Corbet <corbet@lwn.net>  
Signed-off-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
---
 Documentation/admin-guide/kernel-parameters.txt | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index a1068742a6df..9cb126573c71 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -599,6 +599,15 @@
 			altogether. For more information, see
 			include/linux/dma-contiguous.h
 
+        kvm_cma_resv_ratio=n
+                        [PPC]
+                        Reserves given percentage from system memory area for
+                        contiguous memory allocation for KVM hash pagetable
+                        allocation.
+                        Bydefault it reserves 5% of total system memory.
+                        Format: <integer>
+                        Default: 5
+
 	cmo_free_hint=	[PPC] Format: { yes | no }
 			Specify whether pages are marked as being inactive
 			when they are freed.  This is used in CMO environments
-- 
2.26.2