[PATCH] doc: fix readability in lib vhost prog guide

[Herakliusz Lipiec <herakliusz.lipiec@intel.com>]

fix grammar issues and readbility in vhost library programmer guide

Fixes: 768274ebbd5e ("vhost: avoid populate guest memory")
Signed-off-by: Herakliusz Lipiec <herakliusz.lipiec@intel.com>
Cc: stable@dpdk.org
---
 doc/guides/prog_guide/vhost_lib.rst | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/doc/guides/prog_guide/vhost_lib.rst b/doc/guides/prog_guide/vhost_lib.rst
index f287b76ebf..70a0683d5b 100644
--- a/doc/guides/prog_guide/vhost_lib.rst
+++ b/doc/guides/prog_guide/vhost_lib.rst
@@ -310,7 +310,7 @@ vhost-user implementation has two options:
 
      * The vhost supported features must be exactly the same before and
        after the restart. For example, if TSO is disabled and then enabled,
-       nothing will work and issues undefined might happen.
+       nothing will work and undefined issues might happen.
 
 No matter which mode is used, once a connection is established, DPDK
 vhost-user will start receiving and processing vhost messages from QEMU.
@@ -341,21 +341,21 @@ Guest memory requirement
 
 * Memory pre-allocation
 
-  For non-async data path, guest memory pre-allocation is not a
-  must. This can help save of memory. If users really want the guest memory
-  to be pre-allocated (e.g., for performance reason), we can add option
-  ``-mem-prealloc`` when starting QEMU. Or, we can lock all memory at vhost
-  side which will force memory to be allocated when mmap at vhost side;
-  option --mlockall in ovs-dpdk is an example in hand.
+  For non-async data path guest memory pre-allocation is not a
+  must but can help save memory. To do this we can we can add option
+  ``-mem-prealloc`` when starting QEMU, or we can lock all memory at vhost
+  side which will force memory to be allocated when it calls mmap
+  (option --mlockall in ovs-dpdk is an example in hand).
 
+ 
   For async data path, we force the VM memory to be pre-allocated at vhost
   lib when mapping the guest memory; and also we need to lock the memory to
   prevent pages being swapped out to disk.
 
 * Memory sharing
 
-  Make sure ``share=on`` QEMU option is given. vhost-user will not work with
-  a QEMU version without shared memory mapping.
+  Make sure ``share=on`` QEMU option is given. The vhost-user will not work with
+  a QEMU instance without shared memory mapping.
 
 Vhost supported vSwitch reference
 ---------------------------------
-- 
2.17.2