self cleaning nfsiod's

Mike Castle (mcastle@umr.edu)
Fri, 19 Apr 1996 01:50:21 -0500 (CDT)

Is there anything obviously wrong with the following? It seems
fairly stable for me, under 1.3.91. Been sitting here mounting
and unmounting nfs and watching all those happy little nfsiod's
die by themselves.

--- linux/fs/nfs/inode.c.orig Fri Apr 19 00:58:31 1996
+++ linux/fs/nfs/inode.c Fri Apr 19 01:32:07 1996
@@ -322,6 +322,8 @@
nfs_read_super, "nfs", 0, NULL
};

+static pid_t nfsiod_pid[4];
+
/*
* Start up an nfsiod process. This is an awful hack, because when running
* as a module, we will keep insmod's memory. Besides, the current->comm
@@ -330,7 +332,7 @@
* other things) forks biod's.
* Alternatively, we might want to have the idle task spawn biod's on demand.
*/
-static int run_nfsiod(void *dummy)
+static int run_nfsiod(void *my_pid)
{
int ret;

@@ -339,22 +341,21 @@
syscall_count++;
#endif

- MOD_INC_USE_COUNT;
current->session = 1;
current->pgrp = 1;
sprintf(current->comm, "nfsiod");
ret = nfsiod();
- MOD_DEC_USE_COUNT;
+ *(pid_t*)my_pid = -1;
return ret;
}

int init_nfs_fs(void)
{
/* Fork four biod's */
- kernel_thread(run_nfsiod, NULL, 0);
- kernel_thread(run_nfsiod, NULL, 0);
- kernel_thread(run_nfsiod, NULL, 0);
- kernel_thread(run_nfsiod, NULL, 0);
+ nfsiod_pid[0] = kernel_thread(run_nfsiod, &nfsiod_pid[0], 0);
+ nfsiod_pid[1] = kernel_thread(run_nfsiod, &nfsiod_pid[1], 0);
+ nfsiod_pid[2] = kernel_thread(run_nfsiod, &nfsiod_pid[2], 0);
+ nfsiod_pid[3] = kernel_thread(run_nfsiod, &nfsiod_pid[3], 0);
return register_filesystem(&nfs_fs_type);
}

@@ -370,6 +371,23 @@

void cleanup_module(void)
{
+ int i;
+ int done;
+
+ for (i = 0; i < 4; i++) {
+ if (nfsiod_pid[i] != -1) {
+ kill_proc(nfsiod_pid[i], SIGKILL, 1);
+ }
+ }
+
+ do {
+ done = 1;
+ for (i = 0; i < 4; i++) {
+ done &= (nfsiod_pid[i] == -1);
+ }
+ schedule();
+ } while (!done);
+
unregister_filesystem(&nfs_fs_type);
nfs_kfree_cache();
}

-- 
Mike Castle .-=NEXUS=-.  Life is like a clock:  You can work constantly
  mcastle@cs.umr.edu     and be right all the time, or not work at all
   mcastle@umr.edu       and be right at least twice a day.  -- mrc
    We are all of us living in the shadow of Manhattan.  -- Watchmen