2007-10-23 00:49:45

by Paul Menage

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Subject: [PATCH 1/2] CFS CGroup: Code cleanup

Clean up some CFS CGroup code

- replace "cont" with "cgrp" in a few places in the CFS cgroup code,
- use write_uint rather than write for cpu.shares write function

Signed-off-by: Paul Menage <[email protected]>

---
kernel/sched.c | 51 +++++++++++++++++----------------------------------
1 file changed, 17 insertions(+), 34 deletions(-)

Index: container-2.6.23-mm1/kernel/sched.c
===================================================================
--- container-2.6.23-mm1.orig/kernel/sched.c
+++ container-2.6.23-mm1/kernel/sched.c
@@ -6936,25 +6936,25 @@ unsigned long sched_group_shares(struct
#ifdef CONFIG_FAIR_CGROUP_SCHED

/* return corresponding task_group object of a cgroup */
-static inline struct task_group *cgroup_tg(struct cgroup *cont)
+static inline struct task_group *cgroup_tg(struct cgroup *cgrp)
{
- return container_of(cgroup_subsys_state(cont, cpu_cgroup_subsys_id),
- struct task_group, css);
+ return container_of(cgroup_subsys_state(cgrp, cpu_cgroup_subsys_id),
+ struct task_group, css);
}

static struct cgroup_subsys_state *
-cpu_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont)
+cpu_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cgrp)
{
struct task_group *tg;

- if (!cont->parent) {
+ if (!cgrp->parent) {
/* This is early initialization for the top cgroup */
- init_task_group.css.cgroup = cont;
+ init_task_group.css.cgroup = cgrp;
return &init_task_group.css;
}

/* we support only 1-level deep hierarchical scheduler atm */
- if (cont->parent->parent)
+ if (cgrp->parent->parent)
return ERR_PTR(-EINVAL);

tg = sched_create_group();
@@ -6962,21 +6962,21 @@ cpu_cgroup_create(struct cgroup_subsys *
return ERR_PTR(-ENOMEM);

/* Bind the cgroup to task_group object we just created */
- tg->css.cgroup = cont;
+ tg->css.cgroup = cgrp;

return &tg->css;
}

static void cpu_cgroup_destroy(struct cgroup_subsys *ss,
- struct cgroup *cont)
+ struct cgroup *cgrp)
{
- struct task_group *tg = cgroup_tg(cont);
+ struct task_group *tg = cgroup_tg(cgrp);

sched_destroy_group(tg);
}

static int cpu_cgroup_can_attach(struct cgroup_subsys *ss,
- struct cgroup *cont, struct task_struct *tsk)
+ struct cgroup *cgrp, struct task_struct *tsk)
{
/* We don't support RT-tasks being in separate groups */
if (tsk->sched_class != &fair_sched_class)
@@ -6986,38 +6986,21 @@ static int cpu_cgroup_can_attach(struct
}

static void
-cpu_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cont,
+cpu_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
struct cgroup *old_cont, struct task_struct *tsk)
{
sched_move_task(tsk);
}

-static ssize_t cpu_shares_write(struct cgroup *cont, struct cftype *cftype,
- struct file *file, const char __user *userbuf,
- size_t nbytes, loff_t *ppos)
+static int cpu_shares_write_uint(struct cgroup *cgrp, struct cftype *cftype,
+ u64 shareval)
{
- unsigned long shareval;
- struct task_group *tg = cgroup_tg(cont);
- char buffer[2*sizeof(unsigned long) + 1];
- int rc;
-
- if (nbytes > 2*sizeof(unsigned long)) /* safety check */
- return -E2BIG;
-
- if (copy_from_user(buffer, userbuf, nbytes))
- return -EFAULT;
-
- buffer[nbytes] = 0; /* nul-terminate */
- shareval = simple_strtoul(buffer, NULL, 10);
-
- rc = sched_group_set_shares(tg, shareval);
-
- return (rc < 0 ? rc : nbytes);
+ return sched_group_set_shares(cgroup_tg(cgrp), shareval);
}

-static u64 cpu_shares_read_uint(struct cgroup *cont, struct cftype *cft)
+static u64 cpu_shares_read_uint(struct cgroup *cgrp, struct cftype *cft)
{
- struct task_group *tg = cgroup_tg(cont);
+ struct task_group *tg = cgroup_tg(cgrp);

return (u64) tg->shares;
}


2007-10-23 02:34:38

by Srivatsa Vaddagiri

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Subject: Re: [PATCH 1/2] CFS CGroup: Code cleanup

On Mon, Oct 22, 2007 at 05:49:20PM -0700, Paul Menage wrote:
> Clean up some CFS CGroup code
>
> - replace "cont" with "cgrp" in a few places in the CFS cgroup code,

This change looks good to me. Thanks for doing it.

> - use write_uint rather than write for cpu.shares write function

Minor nit: From pov of making this patch series git bisect safe, shouldn't we
be registering a write_uint() handler in this patch as well?

--
Regards,
vatsa

2007-10-23 06:16:54

by Paul Menage

[permalink] [raw]
Subject: Re: [PATCH 1/2] CFS CGroup: Code cleanup

On 10/22/07, Srivatsa Vaddagiri <[email protected]> wrote:
>
> Minor nit: From pov of making this patch series git bisect safe, shouldn't we
> be registering a write_uint() handler in this patch as well?
>

Yes, we should. Sigh. I originally had the cleanup and the new
reporting interface in the same patch, and decided to split them apart
into a cleanup patch and a new feature patch, but clearly goofed. I'll
resend tomorrow with the write_uint registration in the right place.

Paul

2007-10-23 07:42:50

by Paul Menage

[permalink] [raw]
Subject: Re: [PATCH 1/2] CFS CGroup: Code cleanup

On 10/22/07, Paul Menage <[email protected]> wrote:
> On 10/22/07, Srivatsa Vaddagiri <[email protected]> wrote:
> >
> > Minor nit: From pov of making this patch series git bisect safe, shouldn't we
> > be registering a write_uint() handler in this patch as well?
> >
>
> Yes, we should. Sigh. I originally had the cleanup and the new
> reporting interface in the same patch, and decided to split them apart
> into a cleanup patch and a new feature patch, but clearly goofed. I'll
> resend tomorrow with the write_uint registration in the right place.

OK, this wasn't a patch goof - the original patch in my tree does have
the addition of write_uint in the cftype definition. I guess the last
hunk got lost as I transferred it to the email.

Paul