user/sven/linux.git/include/linux/rcutiny.h, branch v4.19.290

rcu: Improve RCU-tasks naming and comments

2018-07-12T22:39:15Z

The naming and comments associated with some RCU-tasks code make the faulty assumption that context switches due to cond_resched() are voluntary. As several people pointed out, this is not the case. This commit therefore updates function names and comments to better reflect current reality. Reported-by: Byungchul Park Reported-by: Joel Fernandes Reported-by: Steven Rostedt Signed-off-by: Paul E. McKenney

rcu/x86: Provide early rcu_cpu_starting() callback

2018-05-22T23:12:26Z

The x86/mtrr code does horrific things because hardware. It uses stop_machine_from_inactive_cpu(), which does a wakeup (of the stopper thread on another CPU), which uses RCU, all before the CPU is onlined. RCU complains about this, because wakeups use RCU and RCU does (rightfully) not consider offline CPUs for grace-periods. Fix this by initializing RCU way early in the MTRR case. Tested-by: Mike Galbraith Signed-off-by: Peter Zijlstra Signed-off-by: Paul E. McKenney [ paulmck: Add !SMP support, per 0day Test Robot report. ]

rcu: Eliminate rcu_irq_enter_disabled()

2017-11-27T16:42:03Z

Now that the irq path uses the rcu_nmi_{enter,exit}() algorithm, rcu_irq_enter() and rcu_irq_exit() may be used from any context. There is thus no need for rcu_irq_enter_disabled() and for the checks using it. This commit therefore eliminates rcu_irq_enter_disabled(). Signed-off-by: Paul E. McKenney

srcu: Move rcu_scheduler_starting() from Tiny RCU to Tiny SRCU

2017-07-24T23:03:22Z

Other than lockdep support, Tiny RCU has no need for the scheduler status. However, Tiny SRCU will need this to control boot-time behavior independent of lockdep. Therefore, this commit moves rcu_scheduler_starting() from kernel/rcu/tiny_plugin.h to kernel/rcu/srcutiny.c. This in turn allows the complete removal of kernel/rcu/tiny_plugin.h. Signed-off-by: Paul E. McKenney

rcu: Remove #ifdef moving rcu_end_inkernel_boot from rcupdate.h

2017-06-09T01:52:40Z

This commit removes a #ifdef and saves a few lines of code by moving the rcu_end_inkernel_boot() function from include/linux/rcupdate.h to include/linux/rcutiny.h (for TINY_RCU) and to include/linux/rcutree.h (for TREE_RCU). Signed-off-by: Paul E. McKenney

rcu: Refactor #includes from include/linux/rcupdate.h

2017-06-09T01:52:37Z

The list of #includes from include/linux/rcupdate.h has grown quite a bit, so it is time to trim it. This commit moves the #include of include/linux/ktime.h to include/linux/rcutiny.h, along with the Tiny-RCU-only function that was the only thing needing ktimem.h. It then reconstructs the files included into include/linux/ktime.h based on what is actually needed, with significant help from the 0day Test Robot. This single change reduces the .i file footprint from rcupdate.h from 9018 lines to 7101 lines. Reported-by: Ingo Molnar Signed-off-by: Paul E. McKenney

rcu: Move rcutiny.h to new empty/true/false-function style

2017-06-09T01:52:34Z

This commit saves a few lines in include/linux/rcutiny.h by moving to single-line definitions for empty functions, instead of the old style where the two curly braces each get their own line. Reported-by: Ingo Molnar Signed-off-by: Paul E. McKenney

rcu: Move rcu_request_urgent_qs_task() out of rcutiny.h and rcutree.h

2017-06-09T01:52:33Z

The rcu_request_urgent_qs_task() function is used only within RCU, so there is no point in exporting it to the rest of the kernel from nclude/linux/rcutiny.h and include/linux/rcutree.h. This commit therefore moves this function to kernel/rcu/rcu.h. Reported-by: Ingo Molnar Signed-off-by: Paul E. McKenney

rcu: Move torture-related functions out of rcutiny.h and rcutree.h

2017-06-09T01:52:33Z

The various functions similar to rcu_batches_started(), the function show_rcu_gp_kthreads(), the various functions similar to rcu_force_quiescent_state(), and the variables rcutorture_testseq and rcutorture_vernum are used only within RCU. There is therefore no point in exporting them to the kernel at large from include/linux/rcutiny.h and include/linux/rcutree.h. This commit therefore moves all of these to kernel/rcu/rcu.h. Reported-by: Ingo Molnar Signed-off-by: Paul E. McKenney

rcu: Eliminate the unused __rcu_is_watching() function

2017-06-09T01:52:30Z

The __rcu_is_watching() function is currently not used, aside from to implement the rcu_is_watching() function. This commit therefore eliminates __rcu_is_watching(), which has the beneficial side-effect of shrinking include/linux/rcupdate.h a bit. Reported-by: Ingo Molnar Signed-off-by: Paul E. McKenney