On Sat 03-11-12 01:38:31, Tejun Heo wrote: > * Make freezer_change_state() take bool @freeze instead of enum > freezer_state. > > * Separate out freezer_apply_state() out of freezer_change_state(). > This makes freezer_change_state() a rather silly thin wrapper. It > will be filled with hierarchy handling later on. > > This patch doesn't introduce any behavior change. > > Signed-off-by: Tejun Heo <[email protected]>
Makes sense Reviewed-by: Michal Hocko <[email protected]> > --- > kernel/cgroup_freezer.c | 48 ++++++++++++++++++++++++++++++------------------ > 1 file changed, 30 insertions(+), 18 deletions(-) > > diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c > index 975b3d8..2690830 100644 > --- a/kernel/cgroup_freezer.c > +++ b/kernel/cgroup_freezer.c > @@ -247,45 +247,57 @@ static void unfreeze_cgroup(struct freezer *freezer) > cgroup_iter_end(cgroup, &it); > } > > -static void freezer_change_state(struct freezer *freezer, > - enum freezer_state goal_state) > +/** > + * freezer_apply_state - apply state change to a single cgroup_freezer > + * @freezer: freezer to apply state change to > + * @freeze: whether to freeze or unfreeze > + */ > +static void freezer_apply_state(struct freezer *freezer, bool freeze) > { > /* also synchronizes against task migration, see freezer_attach() */ > - spin_lock_irq(&freezer->lock); > + lockdep_assert_held(&freezer->lock); > > - switch (goal_state) { > - case CGROUP_THAWED: > - if (freezer->state != CGROUP_THAWED) > - atomic_dec(&system_freezing_cnt); > - freezer->state = CGROUP_THAWED; > - unfreeze_cgroup(freezer); > - break; > - case CGROUP_FROZEN: > + if (freeze) { > if (freezer->state == CGROUP_THAWED) > atomic_inc(&system_freezing_cnt); > freezer->state = CGROUP_FREEZING; > freeze_cgroup(freezer); > - break; > - default: > - BUG(); > + } else { > + if (freezer->state != CGROUP_THAWED) > + atomic_dec(&system_freezing_cnt); > + freezer->state = CGROUP_THAWED; > + unfreeze_cgroup(freezer); > } > +} > > +/** > + * freezer_change_state - change the freezing state of a cgroup_freezer > + * @freezer: freezer of interest > + * @freeze: whether to freeze or thaw > + * > + * Freeze or thaw @cgroup according to @freeze. > + */ > +static void freezer_change_state(struct freezer *freezer, bool freeze) > +{ > + /* update @freezer */ > + spin_lock_irq(&freezer->lock); > + freezer_apply_state(freezer, freeze); > spin_unlock_irq(&freezer->lock); > } > > static int freezer_write(struct cgroup *cgroup, struct cftype *cft, > const char *buffer) > { > - enum freezer_state goal_state; > + bool freeze; > > if (strcmp(buffer, freezer_state_strs[CGROUP_THAWED]) == 0) > - goal_state = CGROUP_THAWED; > + freeze = false; > else if (strcmp(buffer, freezer_state_strs[CGROUP_FROZEN]) == 0) > - goal_state = CGROUP_FROZEN; > + freeze = true; > else > return -EINVAL; > > - freezer_change_state(cgroup_freezer(cgroup), goal_state); > + freezer_change_state(cgroup_freezer(cgroup), freeze); > return 0; > } > > -- > 1.7.11.7 > -- Michal Hocko SUSE Labs -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
