[RFC][PATCH 1/4] Add a beancounter per tgid

[Balbir Singh <balbir@in.ibm.com>]

Create one beancounter per thread group. This is the base patch and serves
as the starting point for aggregating thread groups.

Signed-off-by: Balbir Singh <balbir@in.ibm.com>
---

 kernel/bc/misc.c |   11 +++++++----
 kernel/fork.c    |    4 ++--
 2 files changed, 9 insertions(+), 6 deletions(-)

diff -puN kernel/bc/misc.c~per-tgid-beancounters kernel/bc/misc.c
--- linux-2.6.18-rc5/kernel/bc/misc.c~per-tgid-beancounters	2006-09-12 22:27:02.000000000 +0530
+++ linux-2.6.18-rc5-balbir/kernel/bc/misc.c	2006-09-17 20:30:55.000000000 +0530
@@ -12,15 +12,18 @@
 
 void bc_task_charge(struct task_struct *parent, struct task_struct *new)
 {
-	struct task_beancounter *old_bc;
 	struct task_beancounter *new_bc;
 	struct beancounter *bc;
 
-	old_bc = &parent->task_bc;
 	new_bc = &new->task_bc;
+	bc = beancounter_findcreate(new->tgid, BC_ALLOC);
+	if (!bc) {
+		printk(KERN_WARNING "failed to create bc %d for tgid %d\n",
+			bc->bc_id, new->tgid);
+		return;
+	}
 
-	bc = old_bc->fork_bc;
-	new_bc->exec_bc = get_beancounter(bc);
+	new_bc->exec_bc = bc;
 	new_bc->fork_bc = get_beancounter(bc);
 }
 
diff -puN kernel/fork.c~per-tgid-beancounters kernel/fork.c
--- linux-2.6.18-rc5/kernel/fork.c~per-tgid-beancounters	2006-09-12 22:27:02.000000000 +0530
+++ linux-2.6.18-rc5-balbir/kernel/fork.c	2006-09-12 22:32:26.000000000 +0530
@@ -994,8 +994,6 @@ static struct task_struct *copy_process(
 	if (!p)
 		goto fork_out;
 
-	bc_task_charge(current, p);
-
 #ifdef CONFIG_TRACE_IRQFLAGS
 	DEBUG_LOCKS_WARN_ON(!p->hardirqs_enabled);
 	DEBUG_LOCKS_WARN_ON(!p->softirqs_enabled);
@@ -1106,6 +1104,8 @@ static struct task_struct *copy_process(
 	if (clone_flags & CLONE_THREAD)
 		p->tgid = current->tgid;
 
+	bc_task_charge(current, p);
+
 	if ((retval = security_task_alloc(p)))
 		goto bad_fork_cleanup_policy;
 	if ((retval = audit_alloc(p)))
_

-- 

	Balbir Singh,
	Linux Technology Center,
	IBM Software Labs