Improve user-space page allocator.

    * Allow page allocation system call to force coalesce if a
      contiguous block is unavailable.  [long-term enhancement]

    * Workaround lack of large contiguous memory for PageTable
      test-cases, which require 256K, by allocating a VMM block.
      This should be removed when story 43401 is implemented.
      [short-term workaround]

Change-Id: Idddb30eaa3aeac52d56b82a70355095f31d4a0cd
Reviewed-on: http://gfw160.austin.ibm.com:8080/gerrit/1369
Tested-by: Jenkins Server
Reviewed-by: Daniel M. Crowell <dcrowell@us.ibm.com>
Reviewed-by: Douglas R. Gilbert <dgilbert@us.ibm.com>
Reviewed-by: A. Patrick Williams III <iawillia@us.ibm.com>

1 files changed, 8 insertions, 1 deletions

diff --git a/src/kernel/syscall.C b/src/kernel/syscall.C
index b6fa46f8a..b061a4877 100644
--- a/src/kernel/syscall.C
+++ b/src/kernel/syscall.C
@@ -677,8 +677,10 @@ namespace Systemcalls
      */
     void MmAllocPages(task_t* t)
     {
+        ssize_t pages = TASK_GETARG0(t);
+
         // Attempt to allocate the page(s).
-        void* page = PageManager::allocatePage(TASK_GETARG0(t), true);
+        void* page = PageManager::allocatePage(pages, true);
         TASK_SETRTN(t, reinterpret_cast<uint64_t>(page));
 
         // If we are low on memory, call into the VMM to free some up.
@@ -696,6 +698,11 @@ namespace Systemcalls
                 __sync_lock_release(&one_at_a_time);
             }
         }
+        else if ((page == NULL) && (pages > 1))
+        {
+            CpuManager::forceMemoryPeriodic();
+        }
+
     }
 };