Stop treating system processes as special. This fixes panics

like the one triggered by this:

# kldload geom_vinum
# pwait `pgrep -S gv_worker` &
# kldunload geom_vinum

or this:

GEOM_JOURNAL: Shutting down geom gjournal 3464572051.
panic: destroying non-empty racct: 1 allocated for resource 6

which were tracked by jh@ to be caused by checking p->p_flag,
while it wasn't initialised yet.  Basically, during fork, the code
checked p_flag, concluded the process isn't marked as P_SYSTEM,
incremented the counter, and later on, when exiting, checked that
the process was marked as P_SYSTEM, and thus didn't decrement it.

Also, I believe there wasn't any good reason for checking P_SYSTEM
in the first place.

Tested by:	jh

1 files changed, 0 insertions, 23 deletions

diff --git a/sys/kern/kern_racct.c b/sys/kern/kern_racct.c
index 5ba6773..081b312 100644
--- a/sys/kern/kern_racct.c
+++ b/sys/kern/kern_racct.c
@@ -267,9 +267,6 @@ racct_add_locked(struct proc *p, int resource, uint64_t amount)
 	int error;
 #endif
 
-	if (p->p_flag & P_SYSTEM)
-		return (0);
-
 	SDT_PROBE(racct, kernel, rusage, add, p, resource, amount, 0, 0);
 
 	/*
@@ -344,9 +341,6 @@ void
 racct_add_force(struct proc *p, int resource, uint64_t amount)
 {
 
-	if (p->p_flag & P_SYSTEM)
-		return;
-
 	SDT_PROBE(racct, kernel, rusage, add_force, p, resource, amount, 0, 0);
 
 	/*
@@ -368,9 +362,6 @@ racct_set_locked(struct proc *p, int resource, uint64_t amount)
 	int error;
 #endif
 
-	if (p->p_flag & P_SYSTEM)
-		return (0);
-
 	SDT_PROBE(racct, kernel, rusage, set, p, resource, amount, 0, 0);
 
 	/*
@@ -426,9 +417,6 @@ racct_set_force(struct proc *p, int resource, uint64_t amount)
 {
 	int64_t diff;
 
-	if (p->p_flag & P_SYSTEM)
-		return;
-
 	SDT_PROBE(racct, kernel, rusage, set, p, resource, amount, 0, 0);
 
 	/*
@@ -487,9 +475,6 @@ void
 racct_sub(struct proc *p, int resource, uint64_t amount)
 {
 
-	if (p->p_flag & P_SYSTEM)
-		return;
-
 	SDT_PROBE(racct, kernel, rusage, sub, p, resource, amount, 0, 0);
 
 	/*
@@ -556,12 +541,6 @@ racct_proc_fork(struct proc *parent, struct proc *child)
 	 */
 	racct_create(&child->p_racct);
 
-	/*
-	 * No resource accounting for kernel processes.
-	 */
-	if (child->p_flag & P_SYSTEM)
-		return (0);
-
 	PROC_LOCK(parent);
 	PROC_LOCK(child);
 	mtx_lock(&racct_lock);
@@ -723,8 +702,6 @@ racctd(void)
 		FOREACH_PROC_IN_SYSTEM(p) {
 			if (p->p_state != PRS_NORMAL)
 				continue;
-			if (p->p_flag & P_SYSTEM)
-				continue;
 
 			microuptime(&wallclock);
 			timevalsub(&wallclock, &p->p_stats->p_start);