On Tue, Feb 21, 2023 at 02:57:15PM +0530, Srinivasarao Pathipati wrote: > > On 2/21/2023 12:24 AM, Greg KH wrote: > > On Mon, Feb 20, 2023 at 11:43:59PM +0530, Srinivasarao Pathipati wrote: > > > Making show_rcu_tasks_rude_gp_kthread() function as 'inline' to > > > fix below compilation error. > > > This is applicable to only 5.10 kernels as code got modified > > > in latest kernels. > > > > > > In file included from kernel/rcu/update.c:579:0: > > > kernel/rcu/tasks.h:710:13: error: ‘show_rcu_tasks_rude_gp_kthread’ defined but not used [-Werror=unused-function] > > > static void show_rcu_tasks_rude_gp_kthread(void) {} > > > > > > Signed-off-by: Srinivasarao Pathipati <quic_c_spathi@xxxxxxxxxxx> > > > --- > > > kernel/rcu/tasks.h | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h > > > index 8b51e6a..53ddb4e 100644 > > > --- a/kernel/rcu/tasks.h > > > +++ b/kernel/rcu/tasks.h > > > @@ -707,7 +707,7 @@ static void show_rcu_tasks_rude_gp_kthread(void) > > > #endif /* #ifndef CONFIG_TINY_RCU */ > > > #else /* #ifdef CONFIG_TASKS_RUDE_RCU */ > > > -static void show_rcu_tasks_rude_gp_kthread(void) {} > > > +static inline void show_rcu_tasks_rude_gp_kthread(void) {} > > > #endif /* #else #ifdef CONFIG_TASKS_RUDE_RCU */ > > > //////////////////////////////////////////////////////////////////////// > > > -- > > > 2.7.4 > > > > > What commit id caused this problem? > > commit (8344496e8b49c4122c1808d6cd3f8dc71bccb595 rcu-tasks: Conditionally > compile show_rcu_tasks_gp_kthreads()) introduced this issue So this has been around for a very very long time. Why is this suddenly an issue now, almost 3 years later? What changed to cause this to become an issue? And please put this information in the changelog text. > This patch added conditional macros for definition of > show_rcu_tasks_rude_gp_kthread() but not for dummy definition. > > > And why isn't it an issue in newer kernels, what commit id fixed it and > > why can't we just take that instead? > > Later code got modified with patch (27c0f1448389 rcutorture: Make > grace-period kthread report match RCU flavor being tested) , with this > there won't be compilation issue. > > This patch is part of below series, Not sure all these can be picked to this > 5.10 stable branch so fixed issue by simply making function inline. > > if you think it is better to pick this series, please merge to 5.10 branch. > > https://lore.kernel.org/lkml/20201105233900.GA20676@paulmck-ThinkPad-P72/ > > [1/4] e1eb075ccf37 rcutorture: Make preemptible TRACE02 enable lockdep > [2/4] 77dc174103fd rcu-tasks: Convert rcu_tasks_wait_gp() for-loop to > while-loop > [3/4] 27c0f1448389 rcutorture: Make grace-period kthread report match RCU > flavor being tested > [4/4] 75dc2da5ecd6 rcu-tasks: Make the units of ->init_fract be jiffies I would need you to test and verify that these actually work properly and do not cause any regressions and sign off on them before I could take them. thanks, greg k-h