On Sat, Sep 26, 2020 at 3:30 AM zhuguangqing83 <zhuguangqin...@gmail.com> wrote: > > > > On Thu, Sep 24, 2020 at 10:01 AM <zhuguangqin...@gmail.com> wrote: > > > > > > From: zhuguangqing <zhuguangq...@xiaomi.com> > > > > > > Currently, if CONFIG_SUSPEND=n and CONFIG_CPU_IDLE=y, the function > > > cpuidle_enter_s2idle() is declared but not defined, it may cause error > > > when cpuidle_enter_s2idle() is called. > > > > > > If CONFIG_SUSPEND=y and CONFIG_CPU_IDLE=n, the function > > > cpuidle_enter_s2idle() is defined as "return -ENODEV;" which is not > > > supposed to be. > > > > > > Change #ifdef CONFIG_CPU_IDLE to #ifdef CONFIG_SUSPEND for > > > cpuidle_enter_s2idle() in cpuidle.h, which is consistent with its > > > defination in cpuidle.c. > > > > Well, what about the case when CONFIG_SUSPEND is set, but CONFIG_CPU_IDLE > > isn't? > > > > When CONFIG_SUSPEND is set, but CONFIG_CPU_IDLE isn't, the function > cpuidle_enter_s2idle() is defined in cpuidle.c, but the defination in > cpuidle.c is not used actually because CONFIG_CPU_IDLE isn't set, we > only use its defination as "return -ENODEV;" in cpuidle.h.
Actually, if CONFIG_CPU_IDLE is not set, cpuidle.c is not compiled at all AFAICS, but after the $subject patch the compiler will be looking for cpuidle_enter_s2idle() in that case, won't it? [The static inline stub is only present for CONFIG_SUSPEND unset.] > > > Signed-off-by: zhuguangqing <zhuguangq...@xiaomi.com> > > > --- > > > include/linux/cpuidle.h | 14 +++++++++----- > > > 1 file changed, 9 insertions(+), 5 deletions(-) > > > > > > diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h > > > index 6175c77bf25e..2aa8cead1727 100644 > > > --- a/include/linux/cpuidle.h > > > +++ b/include/linux/cpuidle.h > > > @@ -216,22 +216,26 @@ static inline struct cpuidle_device > > *cpuidle_get_device(void) {return NULL; } > > > extern int cpuidle_find_deepest_state(struct cpuidle_driver *drv, > > > struct cpuidle_device *dev, > > > u64 latency_limit_ns); > > > -extern int cpuidle_enter_s2idle(struct cpuidle_driver *drv, > > > - struct cpuidle_device *dev); > > > extern void cpuidle_use_deepest_state(u64 latency_limit_ns); > > > #else > > > static inline int cpuidle_find_deepest_state(struct cpuidle_driver *drv, > > > struct cpuidle_device *dev, > > > u64 latency_limit_ns) > > > {return -ENODEV; } > > > -static inline int cpuidle_enter_s2idle(struct cpuidle_driver *drv, > > > - struct cpuidle_device *dev) > > > -{return -ENODEV; } > > > static inline void cpuidle_use_deepest_state(u64 latency_limit_ns) > > > { > > > } > > > #endif > > > > > > +#ifdef CONFIG_SUSPEND > > > +extern int cpuidle_enter_s2idle(struct cpuidle_driver *drv, > > > + struct cpuidle_device *dev); > > > +#else > > > +static inline int cpuidle_enter_s2idle(struct cpuidle_driver *drv, > > > + struct cpuidle_device *dev) > > > +{return -ENODEV; } > > > +#endif > > > + > > > /* kernel/sched/idle.c */ > > > extern void sched_idle_set_state(struct cpuidle_state *idle_state); > > > extern void default_idle_call(void); > > > -- > > > 2.17.1 > > > >