Add procfs/kmm to show the state of the kernel heap

ChangeLog

@@ -11459,3 +11459,7 @@
 	* libc/syslog/lib_syslog.c: If syslog timestamping is enabled, don't try to
 	  get the time if the timer hardware has not yet been initialized
 	  (2016-02-05).
+	* fs/procfs/fs_procfskmm.c:  Add /proc/kmm entry that shows that state of
+	  the kernel heap.  Only useful in PROTECTED and KERNEL build modes where
+	  there is a kernel heap (2016-02-06).
+

TODO

@@ -1,4 +1,4 @@
-NuttX TODO List (Last updated February 2, 2016)
+NuttX TODO List (Last updated February 6, 2016)
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 This file summarizes known NuttX bugs, limitations, inconsistencies with
@@ -14,8 +14,8 @@ nuttx/
   (3)  Signals (sched/signal, arch/)
   (2)  pthreads (sched/pthread)
   (0)  Message Queues (sched/mqueue)
-  (7)  Kernel/Protected Build
+  (6)  Kernel/Protected Build
-  (4)  C++ Support
+  (3)  C++ Support
   (6)  Binary loaders (binfmt/)
  (12)  Network (net/, drivers/net)
   (4)  USB (drivers/usbdev, drivers/usbhost)
@@ -463,14 +463,6 @@ o Kernel/Protected Build
   Priority:    Medium/High -- the kernel build configuration is not fully fielded
                yet.
 
-  Title:       NSH free COMMAND LIMITATION
-  Description: The NSH 'free' command only shows memory usage in the user
-               heap only, not usage in the kernel heap.  I am thinking that
-               kernel heap memory usage should be available in /proc/memory.
-               Better /proc/kmm
-  Status:      Open
-  Priority:    Medium/High
-
   Title:       NxTERM PARTITIONING.
   Description: NxTerm is implemented (correctly) as a driver that resides
                in the nuttx/ directory.  However, the user interfaces must be
@@ -590,20 +582,6 @@ o C++ Support
                would be to get a hold of the compilers definition of size_t.
   Priority:    Low.
 
-  Title:       STATIC CONSTRUCTORS
-  Description: Need to call static constructors
-               Update:  Static constructors are implemented for the STM32 F4 and
-               this will provide the model for all solutions.  Basically, if
-               CONFIG_HAVE_CXXINITIALIZE=y is defined in the configuration, then
-               board-specific code must provide the interface up_cxxinitialize().
-               up_cxxinitialize() is called from application logic to initialize
-               all static class instances.  This TODO item probably has to stay
-               open because this solution is only available on STM32 F4.
-  Status:      Open
-  Priority:    Low, depends on toolchain.  Call to gcc's built-in static
-               constructor logic will probably have to be performed by
-               user logic in the application.
-
   Title:       STATIC CONSTRUCTORS AND MULTITASKING
   Description: The logic that calls static constructors operates on the main
                thread of the initial user application task.  Any static

fs/procfs/Kconfig

@@ -48,6 +48,11 @@ config FS_PROCFS_EXCLUDE_CPULOAD
 	default n
 	depends on SCHED_CPULOAD
 
+config FS_PROCFS_EXCLUDE_KMM
+	bool "Exclude kmm"
+	default n
+	depends on MM_KERNEL_HEAP
+
 config FS_PROCFS_EXCLUDE_MOUNTS
 	bool "Exclude mounts"
 	default n

fs/procfs/Make.defs

@@ -1,7 +1,7 @@
 ############################################################################
 # fs/procfs/Make.defs
 #
-#   Copyright (C) 2013 Gregory Nutt. All rights reserved.
+#   Copyright (C) 2013, 2016 Gregory Nutt. All rights reserved.
 #   Author: Gregory Nutt <gnutt@nuttx.org>
 #
 # Redistribution and use in source and binary forms, with or without
@@ -38,7 +38,7 @@ ifeq ($(CONFIG_FS_PROCFS),y)
 
 ASRCS +=
 CSRCS += fs_procfs.c fs_procfsutil.c fs_procfsproc.c fs_procfsuptime.c
-CSRCS += fs_procfscpuload.c
+CSRCS += fs_procfscpuload.c fs_procfskmm.c
 
 # Include procfs build support
 

fs/procfs/fs_procfs.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * fs/procfs/fs_procfs.c
  *
- *   Copyright (C) 2013-2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2013-2016 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -77,6 +77,7 @@
 
 extern const struct procfs_operations proc_operations;
 extern const struct procfs_operations cpuload_operations;
+extern const struct procfs_operations kmm_operations;
 extern const struct procfs_operations module_operations;
 extern const struct procfs_operations uptime_operations;
 
@@ -120,6 +121,10 @@ static const struct procfs_entry_s g_procfs_entries[] =
   { "cpuload",          &cpuload_operations },
 #endif
 
+#if defined(CONFIG_MM_KERNEL_HEAP) && !defined(CONFIG_FS_PROCFS_EXCLUDE_KMM)
+  { "kmm",              &kmm_operations },
+#endif
+
 #if defined(CONFIG_MODULE) && !defined(CONFIG_FS_PROCFS_EXCLUDE_MODULE)
   { "modules",          &module_operations },
 #endif

fs/procfs/fs_procfskmm.c

@@ -0,0 +1,326 @@
+/****************************************************************************
+ * fs/procfs/fs_procfskmm.c
+ *
+ *   Copyright (C) 2016 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <assert.h>
+#include <errno.h>
+#include <debug.h>
+
+#include <nuttx/kmalloc.h>
+#include <nuttx/mm/mm.h>
+#include <nuttx/fs/fs.h>
+#include <nuttx/fs/procfs.h>
+
+#if defined(CONFIG_MM_KERNEL_HEAP) && defined(CONFIG_FS_PROCFS) && \
+   !defined(CONFIG_FS_PROCFS_EXCLUDE_KMM)
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+/* Determines the size of an intermediate buffer that must be large enough
+ * to handle the longest line generated by this logic.
+ */
+
+#define KMM_LINELEN 54
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/* This structure describes one open "file" */
+
+struct kmm_file_s
+{
+  struct procfs_file_s base;      /* Base open file structure */
+  unsigned int linesize;          /* Number of valid characters in line[] */
+  char line[KMM_LINELEN];         /* Pre-allocated buffer for formatted lines */
+};
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/* File system methods */
+
+static int     kmm_open(FAR struct file *filep, FAR const char *relpath,
+                 int oflags, mode_t mode);
+static int     kmm_close(FAR struct file *filep);
+static ssize_t kmm_read(FAR struct file *filep, FAR char *buffer,
+                 size_t buflen);
+static int     kmm_dup(FAR const struct file *oldp,
+                 FAR struct file *newp);
+static int     kmm_stat(FAR const char *relpath, FAR struct stat *buf);
+
+/****************************************************************************
+ * Private Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/* See fs_mount.c -- this structure is explicitly externed there.
+ * We use the old-fashioned kind of initializers so that this will compile
+ * with any compiler.
+ */
+
+const struct procfs_operations kmm_operations =
+{
+  kmm_open,       /* open */
+  kmm_close,      /* close */
+  kmm_read,       /* read */
+  NULL,           /* write */
+  kmm_dup,        /* dup */
+  NULL,           /* opendir */
+  NULL,           /* closedir */
+  NULL,           /* readdir */
+  NULL,           /* rewinddir */
+  kmm_stat        /* stat */
+};
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: kmm_open
+ ****************************************************************************/
+
+static int kmm_open(FAR struct file *filep, FAR const char *relpath,
+                      int oflags, mode_t mode)
+{
+  FAR struct kmm_file_s *procfile;
+
+  fvdbg("Open '%s'\n", relpath);
+
+  /* PROCFS is read-only.  Any attempt to open with any kind of write
+   * access is not permitted.
+   *
+   * REVISIT:  Write-able proc files could be quite useful.
+   */
+
+  if ((oflags & O_WRONLY) != 0 || (oflags & O_RDONLY) == 0)
+    {
+      fdbg("ERROR: Only O_RDONLY supported\n");
+      return -EACCES;
+    }
+
+  /* "kmm" is the only acceptable value for the relpath */
+
+  if (strcmp(relpath, "kmm") != 0)
+    {
+      fdbg("ERROR: relpath is '%s'\n", relpath);
+      return -ENOENT;
+    }
+
+  /* Allocate a container to hold the file attributes */
+
+  procfile = (FAR struct kmm_file_s *)kmm_zalloc(sizeof(struct kmm_file_s));
+  if (!procfile)
+    {
+      fdbg("ERROR: Failed to allocate file attributes\n");
+      return -ENOMEM;
+    }
+
+  /* Save the attributes as the open-specific state in filep->f_priv */
+
+  filep->f_priv = (FAR void *)procfile;
+  return OK;
+}
+
+/****************************************************************************
+ * Name: kmm_close
+ ****************************************************************************/
+
+static int kmm_close(FAR struct file *filep)
+{
+  FAR struct kmm_file_s *procfile;
+
+  /* Recover our private data from the struct file instance */
+
+  procfile = (FAR struct kmm_file_s *)filep->f_priv;
+  DEBUGASSERT(procfile);
+
+  /* Release the file attributes structure */
+
+  kmm_free(procfile);
+  filep->f_priv = NULL;
+  return OK;
+}
+
+/****************************************************************************
+ * Name: kmm_read
+ ****************************************************************************/
+
+static ssize_t kmm_read(FAR struct file *filep, FAR char *buffer,
+                           size_t buflen)
+{
+  FAR struct kmm_file_s *procfile;
+  struct mallinfo mem;
+  size_t linesize;
+  size_t copysize;
+  size_t totalsize;
+  off_t offset;
+
+  fvdbg("buffer=%p buflen=%d\n", buffer, (int)buflen);
+
+  DEBUGASSERT(filep != NULL && buffer != NULL && buflen > 0);
+  offset = filep->f_pos;
+
+  /* Recover our private data from the struct file instance */
+
+  procfile = (FAR struct kmm_file_s *)filep->f_priv;
+  DEBUGASSERT(procfile);
+
+  /* The first line is the headers */
+
+  linesize  = snprintf(procfile->line, KMM_LINELEN,
+                       "             total       used       free    largest\n");
+  copysize  = procfs_memcpy(procfile->line, linesize, buffer, buflen,
+                            &offset);
+  totalsize = copysize;
+
+  if (totalsize < buflen)
+    {
+      buffer += copysize;
+      buflen -= copysize;
+
+      /* The second line is the memory data */
+
+#ifdef CONFIG_CAN_PASS_STRUCTS
+      mem = kmm_mallinfo();
+#else
+      (void)kmm_mallinfo(&mem);
+#endif
+
+      linesize   = snprintf(procfile->line, KMM_LINELEN,
+                            "Mem:   %11d%11d%11d%11d\n",
+                            mem.arena, mem.uordblks, mem.fordblks,
+                            mem.mxordblk);
+      copysize   = procfs_memcpy(procfile->line, linesize, buffer, buflen,
+                                 &offset);
+      totalsize += copysize;
+    }
+
+  /* Update the file offset */
+
+  filep->f_pos += totalsize;
+  return totalsize;
+}
+
+/****************************************************************************
+ * Name: kmm_dup
+ *
+ * Description:
+ *   Duplicate open file data in the new file structure.
+ *
+ ****************************************************************************/
+
+static int kmm_dup(FAR const struct file *oldp, FAR struct file *newp)
+{
+  FAR struct kmm_file_s *oldattr;
+  FAR struct kmm_file_s *newattr;
+
+  fvdbg("Dup %p->%p\n", oldp, newp);
+
+  /* Recover our private data from the old struct file instance */
+
+  oldattr = (FAR struct kmm_file_s *)oldp->f_priv;
+  DEBUGASSERT(oldattr);
+
+  /* Allocate a new container to hold the task and attribute selection */
+
+  newattr = (FAR struct kmm_file_s *)kmm_malloc(sizeof(struct kmm_file_s));
+  if (!newattr)
+    {
+      fdbg("ERROR: Failed to allocate file attributes\n");
+      return -ENOMEM;
+    }
+
+  /* The copy the file attributes from the old attributes to the new */
+
+  memcpy(newattr, oldattr, sizeof(struct kmm_file_s));
+
+  /* Save the new attributes in the new file structure */
+
+  newp->f_priv = (FAR void *)newattr;
+  return OK;
+}
+
+/****************************************************************************
+ * Name: kmm_stat
+ *
+ * Description: Return information about a file or directory
+ *
+ ****************************************************************************/
+
+static int kmm_stat(FAR const char *relpath, FAR struct stat *buf)
+{
+  /* "kmm" is the only acceptable value for the relpath */
+
+  if (strcmp(relpath, "kmm") != 0)
+    {
+      fdbg("ERROR: relpath is '%s'\n", relpath);
+      return -ENOENT;
+    }
+
+  /* "kmm" is the name for a read-only file */
+
+  buf->st_mode    = S_IFREG | S_IROTH | S_IRGRP | S_IRUSR;
+  buf->st_size    = 0;
+  buf->st_blksize = 0;
+  buf->st_blocks  = 0;
+  return OK;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+#endif /* CONFIG_MM_KERNEL_HEAP && CONFIG_FS_PROCFS && !CONFIG_FS_PROCFS_EXCLUDE_KMM */

include/nuttx/mm/mm.h

@@ -491,8 +491,8 @@ int mm_mallinfo(FAR struct mm_heap_s *heap, FAR struct mallinfo *info);
 struct mallinfo kmm_mallinfo(void);
 #else
 int kmm_mallinfo(struct mallinfo *info);
-#endif
 #endif /* CONFIG_CAN_PASS_STRUCTS */
+#endif /* CONFIG_MM_KERNEL_HEAP */
 
 /* Functions contained in mm_shrinkchunk.c **********************************/