xserver: Branch 'master'

[GitLab Mirror]

 dix/resource.c |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

New commits:
commit c73116540205c20162befe935ef608f4bed3af0a
Author: Olivier Fourdan <ofourdan at redhat.com>
Date:   Fri Nov 30 13:09:53 2018 +0100

    dix: cache ResourceClientBits() value
    
    The `LimitClient` is set once and for all at startup, whereas the
    function `ResourceClientBits()` which returns the client field offset
    within the XID based on the value of `LimitClient` can be called
    repeatedly.
    
    Small optimization, cache the result of `ilog2()`, that saves running
    the same loop over and over each time `ResourceClientBits()` is called.
    
    Signed-off-by: Olivier Fourdan <ofourdan at redhat.com>

diff --git a/dix/resource.c b/dix/resource.c
index b6ef99f10..a42cd007f 100644
--- a/dix/resource.c
+++ b/dix/resource.c
@@ -620,7 +620,12 @@ ilog2(int val)
 unsigned int
 ResourceClientBits(void)
 {
-    return (ilog2(LimitClients));
+    static unsigned int cached = 0;
+
+    if (cached == 0)
+      cached = ilog2(LimitClients);
+
+    return cached;
 }
 
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