Fixes for granule allocator

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5131 42af7a65-404d-4744-a932-0658087f49c3

include/nuttx/gran.h

@@ -106,8 +106,8 @@ extern "C" {
  ****************************************************************************/
 
 #ifdef CONFIG_GRAN_SINGLE
-EXTERN void gran_initialize(FAR void *heapstart, size_t heapsize,
-                            uint8_t log2gran);
+EXTERN int gran_initialize(FAR void *heapstart, size_t heapsize,
+                           uint8_t log2gran);
 #else
 EXTERN GRAN_HANDLE gran_initialize(FAR void *heapstart, size_t heapsize,
                                    uint8_t log2gran);

mm/Makefile

@@ -41,7 +41,7 @@ CSRCS	= mm_initialize.c mm_sem.c  mm_addfreechunk.c mm_size2ndx.c mm_shrinkchunk
 	  mm_memalign.c mm_free.c mm_mallinfo.c
 
 ifeq ($(CONFIG_GRAN),y)
-CSRCS	= mm_graninit.c mm_granalloc.c mm_granfree.c
+CSRCS	+= mm_graninit.c mm_granalloc.c mm_granfree.c
 endif
 
 AOBJS	= $(ASRCS:.S=$(OBJEXT))

mm/mm_gran.h

@@ -43,6 +43,7 @@
 #include <nuttx/config.h>
 
 #include <stdint.h>
+#include <semaphore.h>
 
 #include <nuttx/gran.h>
 
@@ -87,6 +88,7 @@ struct gran_s
 {
   uint8_t    log2gran;  /* Log base 2 of the size of one granule */
   uint16_t   ngranules; /* The total number of (aligned) granules in the heap */
+  sem_t      exclsem;   /* For exclusive access to the GAT */
   uintptr_t  heapstart; /* The aligned start of the granule heap */
   uint32_t   gat[1];    /* Start of the granule allocation table */
 };
@@ -105,4 +107,22 @@ extern FAR struct gran_s *g_graninfo;
  * Public Function Prototypes
  ****************************************************************************/
 
+/****************************************************************************
+ * Name: gran_semtake and gran_semgive
+ *
+ * Description:
+ *   Managed semaphore for the granule allocator.  gran_semgive is
+ *   implemented as a macro.
+ *
+ * Input Parameters:
+ *   priv - Pointer to the gran state
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
+void gran_semtake(FAR struct gran_s *priv);
+#define gran_semgive(p) sem_post(&(p)->exclsem);
+
 #endif /* __MM_MM_GRAN_H */

mm/mm_granalloc.c

@@ -93,7 +93,7 @@ static inline void gran_mark_allocated(FAR struct gran_s *priv, uintptr_t alloc,
       ngranules -= avail;
     }
 
-  /* Handle the cae where where all of the granules come from one entry */
+  /* Handle the case where where all of the granules come from one entry */
 
   else
     {
@@ -135,8 +135,13 @@ static inline FAR void *gran_common_alloc(FAR struct gran_s *priv, size_t size)
   int           j;
 
   DEBUGASSERT(priv && size <= 32 * (1 << priv->log2gran));
+
   if (priv && size > 0)
     {
+      /* Get exclusive access to the GAT */
+
+      gran_semtake(priv);
+
       /* How many contiguous granules we we need to find? */
 
       tmpmask   = (1 << priv->log2gran) - 1;
@@ -186,6 +191,7 @@ static inline FAR void *gran_common_alloc(FAR struct gran_s *priv, size_t size)
 
                   /* And return the allocation address */
 
+                  gran_semgive(priv);
                   return (FAR void *)alloc;
                 }
 
@@ -207,6 +213,7 @@ static inline FAR void *gran_common_alloc(FAR struct gran_s *priv, size_t size)
         }
     }
 
+  gran_semgive(priv);
   return NULL;
 }
 

mm/mm_granfree.c

@@ -79,6 +79,10 @@ static inline void gran_common_free(FAR struct gran_s *priv,
 
   DEBUGASSERT(priv && memory && size <= 32 * (1 << priv->log2gran));
 
+  /* Get exclusive access to the GAT */
+
+  gran_semtake(priv);
+
   /* Determine the granule number of the first granule in the allocation */
 
   granno = ((uintptr_t)memory - priv->heapstart) >> priv->log2gran;
@@ -102,21 +106,22 @@ static inline void gran_common_free(FAR struct gran_s *priv,
     {
       priv->gat[gatidx] &= ~(0xffffffff << gatbit);
       ngranules -= avail;
+
+      /* Clear bits in the second GAT entry */
+
+      gatmask = 0xffffffff >> (32 - ngranules);
+      priv->gat[gatidx+1] &= ~(gatmask << gatbit);
     }
 
-  /* Handle the cae where where all of the granules came from one entry */
+  /* Handle the case where where all of the granules came from one entry */
 
   else
     {
       gatmask = 0xffffffff >> (32 - ngranules);
       priv->gat[gatidx] &= ~(gatmask << gatbit);
-      return;
     }
 
-  /* Clear bits in the second GAT entry */
-
-  gatmask = 0xffffffff >> (32 - ngranules);
-  priv->gat[gatidx+1] &= ~(gatmask << gatbit);
+  gran_semgive(priv);
 }
 
 /****************************************************************************

mm/mm_graninit.c

@@ -40,6 +40,8 @@
 #include <nuttx/config.h>
 
 #include <stdlib.h>
+#include <assert.h>
+#include <errno.h>
 
 #include <nuttx/gran.h>
 
@@ -95,6 +97,8 @@ static inline FAR struct gran_s *gran_common_initialize(FAR void *heapstart,
   unsigned int       alignedsize;
   unsigned int       ngranules;
 
+  DEBUGASSERT(heapstart && heapsize > 0 && log2gran > 0 && log2gran < 32);
+
   /* Determine the number of granules */
 
   mask         = (1 << log2gran) - 1;
@@ -115,6 +119,7 @@ static inline FAR struct gran_s *gran_common_initialize(FAR void *heapstart,
       priv->log2gran  = log2gran;
       priv->ngranules = ngranules;
       priv->heapstart = alignedstart;
+      sem_init(&priv->exclsem, 0, 1);
     }
 
   return priv;
@@ -153,7 +158,7 @@ static inline FAR struct gran_s *gran_common_initialize(FAR void *heapstart,
 int gran_initialize(FAR void *heapstart, size_t heapsize, uint8_t log2gran)
 {
   g_graninfo = gran_common_initialize(heapstart, heapsize, log2gran);
-  if (!g_granifo)
+  if (!g_graninfo)
     {
       return -ENOMEM;
     }
@@ -167,6 +172,38 @@ GRAN_HANDLE gran_initialize(FAR void *heapstart, size_t heapsize, uint8_t log2gr
 }
 #endif
 
+/****************************************************************************
+ * Name: gran_semtake and gran_semgive
+ *
+ * Description:
+ *   Managed semaphore for the granule allocator.  gran_semgive is
+ *   implemented as a macro.
+ *
+ * Input Parameters:
+ *   priv - Pointer to the gran state
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
+void gran_semtake(FAR struct gran_s *priv)
+{
+  int ret;
+
+  /* Continue waiting if we are awakened by a signal */
+
+  do
+    {
+      ret = sem_wait(&priv->exclsem);
+      if (ret < 0)
+        {
+          DEBUGASSERT(errno == EINTR);
+        }
+    }
+  while (ret < 0);
+}
+
 #endif /* CONFIG_GRAN */