xen-devel.lists.xenproject.org archive mirror
 help / color / mirror / Atom feed
From: Julien Grall <julien.grall@arm.com>
To: xen-devel@lists.xen.org
Cc: George Dunlap <george.dunlap@eu.citrix.com>,
	Andrew Cooper <andrew.cooper3@citrix.com>,
	Julien Grall <julien.grall@arm.com>,
	Jan Beulich <jbeulich@suse.com>
Subject: [PATCH 05/15] xen/x86: p2m-pod: Avoid redundant assignments in p2m_pod_demand_populate
Date: Wed, 13 Sep 2017 18:59:43 +0100	[thread overview]
Message-ID: <20170913175953.16942-6-julien.grall@arm.com> (raw)
In-Reply-To: <20170913175953.16942-1-julien.grall@arm.com>

gfn_aligned is assigned 3 times with the exact same formula. All the
variables used are not modified, so consolidate in a single assignment
at the beginning of the function.

Signed-off-by: Julien Grall <julien.grall@arm.com>

---

Cc: George Dunlap <george.dunlap@eu.citrix.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
---
 xen/arch/x86/mm/p2m-pod.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/xen/arch/x86/mm/p2m-pod.c b/xen/arch/x86/mm/p2m-pod.c
index f04d6e03e2..bcc87aee03 100644
--- a/xen/arch/x86/mm/p2m-pod.c
+++ b/xen/arch/x86/mm/p2m-pod.c
@@ -1079,7 +1079,7 @@ p2m_pod_demand_populate(struct p2m_domain *p2m, unsigned long gfn,
 {
     struct domain *d = p2m->domain;
     struct page_info *p = NULL; /* Compiler warnings */
-    unsigned long gfn_aligned;
+    unsigned long gfn_aligned = (gfn >> order) << order;
     mfn_t mfn;
     unsigned long i;
 
@@ -1102,7 +1102,6 @@ p2m_pod_demand_populate(struct p2m_domain *p2m, unsigned long gfn,
     if ( order == PAGE_ORDER_1G )
     {
         pod_unlock(p2m);
-        gfn_aligned = (gfn >> order) << order;
         /*
          * Note that we are supposed to call p2m_set_entry() 512 times to
          * split 1GB into 512 2MB pages here. But We only do once here because
@@ -1147,8 +1146,6 @@ p2m_pod_demand_populate(struct p2m_domain *p2m, unsigned long gfn,
 
     BUG_ON((mfn_x(mfn) & ((1UL << order) - 1)) != 0);
 
-    gfn_aligned = (gfn >> order) << order;
-
     p2m_set_entry(p2m, gfn_aligned, mfn, order, p2m_ram_rw,
                   p2m->default_access);
 
@@ -1200,7 +1197,6 @@ remap_and_retry:
      * NOTE: In a p2m fine-grained lock scenario this might
      * need promoting the gfn lock from gfn->2M superpage.
      */
-    gfn_aligned = (gfn >> order) << order;
     for ( i = 0; i < (1UL << order); i++ )
         p2m_set_entry(p2m, gfn_aligned + i, INVALID_MFN, PAGE_ORDER_4K,
                       p2m_populate_on_demand, p2m->default_access);
-- 
2.11.0


_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel

  parent reply	other threads:[~2017-09-13 17:59 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-09-13 17:59 [PATCH 00/15] xen/x86: Clean-up the PoD code Julien Grall
2017-09-13 17:59 ` [PATCH 01/15] xen/x86: p2m-pod: Clean-up includes Julien Grall
2017-09-13 17:59 ` [PATCH 02/15] xen/x86: p2m-pod: Remove trailing whitespaces Julien Grall
2017-09-13 17:59 ` [PATCH 03/15] xen/x86: p2m-pod: Fix coding style for comments Julien Grall
2017-09-13 17:59 ` [PATCH 04/15] xen/x86: p2m-pod: Fix coding style Julien Grall
2017-09-13 17:59 ` Julien Grall [this message]
2017-09-13 17:59 ` [PATCH 06/15] xen/x86: p2m-pod: Clean-up use of typesafe MFN Julien Grall
2017-09-13 17:59 ` [PATCH 07/15] xen/x86: p2m-pod: Use typesafe gfn in p2m_pod_decrease_reservation Julien Grall
2017-09-13 17:59 ` [PATCH 08/15] xen/x86: p2m: Use typesafe gfn for the P2M callbacks get_entry and set_entry Julien Grall
2017-09-13 18:22   ` Andrew Cooper
2017-09-13 18:27     ` Julien Grall
2017-09-13 19:10       ` Razvan Cojocaru
2017-09-13 19:08   ` Razvan Cojocaru
2017-09-13 19:32     ` Julien Grall
2017-09-20  6:57   ` Tian, Kevin
2017-09-13 17:59 ` [PATCH 09/15] xen/x86: p2m: Use typesafe GFN in p2m_set_entry Julien Grall
2017-09-13 20:16   ` Tamas K Lengyel
2017-09-13 17:59 ` [PATCH 10/15] xen/x86: p2m-pod: Use typesafe GFN in pod_eager_record Julien Grall
2017-09-13 17:59 ` [PATCH 11/15] xen/x86: p2m-pod: Clean-up p2m_pod_zero_check Julien Grall
2017-09-13 17:59 ` [PATCH 12/15] xen/x86: p2m-pod: Use typesafe gfn in p2m_pod_zero_check Julien Grall
2017-09-13 17:59 ` [PATCH 13/15] xen/x86: p2m-pod: Use typesafe gfn in p2m_pod_demand_populate Julien Grall
2017-09-13 17:59 ` [PATCH 14/15] xen/x86: p2m-pod: Use typesafe gfn for the fields reclaim_single and max_guest Julien Grall
2017-09-13 17:59 ` [PATCH 15/15] xen/x86: p2m-pod: Rework prototype of p2m_pod_demand_populate Julien Grall
2017-09-13 18:30 ` [PATCH 00/15] xen/x86: Clean-up the PoD code Andrew Cooper

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20170913175953.16942-6-julien.grall@arm.com \
    --to=julien.grall@arm.com \
    --cc=andrew.cooper3@citrix.com \
    --cc=george.dunlap@eu.citrix.com \
    --cc=jbeulich@suse.com \
    --cc=xen-devel@lists.xen.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).