From: Tomas Hruby <tom@minix3.org>
Date: Tue, 13 Apr 2010 10:45:08 +0000 (+0000)
Subject: PM remembers what it should schedule
X-Git-Tag: v3.1.7~150
X-Git-Url: http://zhaoyanbai.com/repos/?a=commitdiff_plain;h=86378ff645f2ca1fec97764e1adda649ad7fcba2;p=minix.git

PM remembers what it should schedule

- while PM implements fork also for RS it needs to remember what to
  schedule and what not. PM_SCHEDULED flag serves this purpose.

- PM only schedules processes that are descendaints of init, i.e. normal
  user processes

- after a process is forked PM schedules for the first time only
  processes that have PM_SCHEDULED set. The others are handled iether
  by kernel or some other scheduler
---

diff --git a/servers/pm/forkexit.c b/servers/pm/forkexit.c
index 3406296c2..17a8c9f8d 100644
--- a/servers/pm/forkexit.c
+++ b/servers/pm/forkexit.c
@@ -92,7 +92,7 @@ PUBLIC int do_fork()
 	sigemptyset(&rmc->mp_sigtrace);
   }
   /* Inherit only these flags. In normal fork(), PRIV_PROC is not inherited. */
-  rmc->mp_flags &= (IN_USE|DELAY_CALL);
+  rmc->mp_flags &= (IN_USE|DELAY_CALL|PM_SCHEDULED);
   rmc->mp_child_utime = 0;		/* reset administration */
   rmc->mp_child_stime = 0;		/* reset administration */
   rmc->mp_exitstatus = 0;
diff --git a/servers/pm/main.c b/servers/pm/main.c
index 2fdafbb93..41d3c4106 100644
--- a/servers/pm/main.c
+++ b/servers/pm/main.c
@@ -505,7 +505,8 @@ PRIVATE void handle_fs_reply()
 
   case PM_FORK_REPLY:
 	/* Schedule the newly created process ... */
-	schedule_process(rmp);
+	if (rmp->mp_flags & PM_SCHEDULED)
+		schedule_process(rmp);
 	/* ... and wake it up */
 	setreply(proc_n, OK);
 
diff --git a/servers/pm/mproc.h b/servers/pm/mproc.h
index 358e93e50..bb4cbf7bb 100644
--- a/servers/pm/mproc.h
+++ b/servers/pm/mproc.h
@@ -82,6 +82,7 @@ EXTERN struct mproc {
 #define TRACE_EXIT	0x08000	/* tracer is forcing this process to exit */
 #define TRACE_ZOMBIE	0x10000	/* waiting for tracer to issue WAIT call */
 #define DELAY_CALL	0x20000	/* waiting for call before sending signal */
+#define PM_SCHEDULED	0x40000 /* this process is scheduled by PM */
 
 #define NIL_MPROC ((struct mproc *) 0)
 
diff --git a/servers/pm/schedule.c b/servers/pm/schedule.c
index 590ce45d2..2f6ee3d24 100644
--- a/servers/pm/schedule.c
+++ b/servers/pm/schedule.c
@@ -69,6 +69,7 @@ PUBLIC void overtake_scheduling(void)
 			if (sys_schedctl(trmp->mp_endpoint))
 				printf("PM: Error while overtaking scheduling for %s\n",
 					trmp->mp_name);
+			trmp->mp_flags |= PM_SCHEDULED;
 		}
 	}