[libcvd-members] libcvd configure.in cvd/image.h

[Ethan Eade]

CVSROOT:        /cvsroot/libcvd
Module name:    libcvd
Changes by:     Ethan Eade <ethaneade>  06/11/28 15:32:56

Modified files:
        .              : configure.in 
        cvd            : image.h 

Log message:
        Use posix_memalign for allocating aligned image blocks, when available.
        The configure script now checks for posix_memalign, and image.h uses it
        instead of aligned_mem, if available.  This eliminates the locking 
problem
        on POSIX systems.

CVSWeb URLs:
http://cvs.savannah.gnu.org/viewcvs/libcvd/configure.in?cvsroot=libcvd&r1=1.74&r2=1.75
http://cvs.savannah.gnu.org/viewcvs/libcvd/cvd/image.h?cvsroot=libcvd&r1=1.30&r2=1.31

Patches:
Index: configure.in
===================================================================
RCS file: /cvsroot/libcvd/libcvd/configure.in,v
retrieving revision 1.74
retrieving revision 1.75
diff -u -b -r1.74 -r1.75
--- configure.in        24 Oct 2006 13:02:29 -0000      1.74
+++ configure.in        28 Nov 2006 15:32:55 -0000      1.75
@@ -662,6 +662,19 @@
                        fi
                fi
 
+               AC_MSG_CHECKING(for posix_memalign)
+               a=0
+               AC_COMPILE_IFELSE([#include <stdlib.h>
+                                               int main(){void* mem; 
posix_memalign(&mem,16,100); return 0;}],[a=1])
+               if test $a == 1
+               then
+                       AC_MSG_RESULT(yes)
+                       AC_DEFINE(CVD_HAVE_MEMALIGN, 1)
+                       AC_SUBST(have_memalign,yes)
+               else
+                       AC_MSG_RESULT(no)
+                       AC_SUBST(have_memalign,no)
+               fi              
                
                AC_MSG_CHECKING([kernel major number])
                kernel_major=[`uname -r | $AWK -F'[.-]' '{print $1}'`]

Index: cvd/image.h
===================================================================
RCS file: /cvsroot/libcvd/libcvd/cvd/image.h,v
retrieving revision 1.30
retrieving revision 1.31
diff -u -b -r1.30 -r1.31
--- cvd/image.h 18 Nov 2006 10:12:33 -0000      1.30
+++ cvd/image.h 28 Nov 2006 15:32:55 -0000      1.31
@@ -40,6 +40,7 @@
 #include <utility>
 #include <iterator>
 #include <cvd/internal/aligned_mem.h>
+#include <stdlib.h>
 
 namespace CVD {
 
@@ -740,7 +741,14 @@
                        *num_copies = 1;
                        this->my_size = size;
                        this->my_stride = size.x;
+#if CVD_HAVE_MEMALIGN
+                       void* mem=0;
+                       const int alloc_err = posix_memalign(&mem, 16, 
this->totalsize()*sizeof(T));
+                       assert(alloc_err == 0);
+                       this->my_data = new (mem) T[this->totalsize()];
+#else
                        this->my_data = 
Internal::aligned_mem<T,16>::alloc(this->totalsize());
+#endif
                }
 
                ///Create a filled image of a given size
@@ -797,7 +805,12 @@
                {
                        if(this->my_data && *num_copies && --(*num_copies) == 0)
                        {
+#if CVD_HAVE_MEMALIGN
+                           Internal::placement_delete<T>::free(this->my_data, 
this->totalsize());
+                           free(this->my_data);
+#else
                          Internal::aligned_mem<T,16>::release(this->my_data);
+#endif
                          this->my_data = 0;
                          delete   num_copies;
                          num_copies = 0;