fs/procfs: Supports any number of thread displays

After the number of threads exceeds the array size, it will not be displayed.
Any number of threads can be displayed using dynamic adaptation

Signed-off-by: yinshengkai <[email protected]>

Author: Gary-Hobson

boards/arm/stm32f7/nucleo-144/configs/f746-pysim/defconfig

@@ -34,7 +34,6 @@ CONFIG_DEV_GPIO=y
 CONFIG_ETH0_PHY_LAN8742A=y
 CONFIG_FS_PROCFS=y
 CONFIG_FS_PROCFS_EXCLUDE_ENVIRON=y
-CONFIG_FS_PROCFS_MAX_TASKS=16
 CONFIG_FS_PROCFS_REGISTER=y
 CONFIG_HAVE_CXX=y
 CONFIG_HAVE_CXXINITIALIZE=y

fs/procfs/Kconfig

@@ -21,12 +21,6 @@ config FS_PROCFS_REGISTER
 		Support run-time registration of the new entries in the procfs file
 		system.
 
-config FS_PROCFS_MAX_TASKS
-	int "The maximum number of active tasks for procfs snapshot"
-	default 128
-	---help---
-		The maximum number of active tasks for procfs snapshot.
-
 menu "Exclude individual procfs entries"
 
 config FS_PROCFS_EXCLUDE_BLOCKS

fs/procfs/fs_procfs.c

@@ -47,6 +47,7 @@
 #include <nuttx/fs/procfs.h>
 
 #include "mount/mount.h"
+#include "sched/sched.h"
 
 /****************************************************************************
  * External Definitions
@@ -315,8 +316,8 @@ struct procfs_level0_s
   /* Our private data */
 
   uint8_t lastlen;                       /* length of last reported static dir */
-  pid_t pid[CONFIG_FS_PROCFS_MAX_TASKS]; /* Snapshot of all active task IDs */
   FAR const char *lastread;              /* Pointer to last static dir read */
+  pid_t pid[1];                          /* Snapshot of all active task IDs */
 };
 
 /* Level 1 is an internal virtual directory (such as /proc/fs) which
@@ -355,14 +356,14 @@ static void procfs_enum(FAR struct tcb_s *tcb, FAR void *arg)
 
   /* Add the PID to the list */
 
-  index = dir->base.nentries;
-  if (index >= CONFIG_FS_PROCFS_MAX_TASKS)
+  if (dir->base.index >= dir->base.nentries)
     {
       return;
     }
 
+  index = dir->base.index;
   dir->pid[index] = tcb->pid;
-  dir->base.nentries = index + 1;
+  dir->base.index = index + 1;
 }
 
 /****************************************************************************
@@ -633,12 +634,18 @@ static int procfs_opendir(FAR struct inode *mountpt, FAR const char *relpath,
 
   if (!relpath || relpath[0] == '\0')
     {
+      size_t num = 0;
+
       /* The path refers to the top level directory.  Allocate the level0
        * dirent structure.
        */
 
+#ifndef CONFIG_FS_PROCFS_EXCLUDE_PROCESS
+      num = g_npidhash;
+#endif
+
       level0 = (FAR struct procfs_level0_s *)
-         kmm_zalloc(sizeof(struct procfs_level0_s));
+         kmm_zalloc(sizeof(struct procfs_level0_s) + sizeof(pid_t) * num) ;
       if (!level0)
         {
           ferr("ERROR: Failed to allocate the level0 directory structure\n");
@@ -653,7 +660,11 @@ static int procfs_opendir(FAR struct inode *mountpt, FAR const char *relpath,
        */
 
 #ifndef CONFIG_FS_PROCFS_EXCLUDE_PROCESS
+      level0->base.index = 0;
+      level0->base.nentries = num;
       nxsched_foreach(procfs_enum, level0);
+      level0->base.nentries = level0->base.index;
+      level0->base.index = 0;
       procfs_sort_pid(level0);
 #else
       level0->base.index = 0;