Re: [PATCH 01/12] housekeeping: Move housekeeping related code to its own file

From: Paul E. McKenney
Date: Tue Oct 24 2017 - 09:36:03 EST

Next message: Frederic Weisbecker: "[PATCH 01/12] housekeeping: Move housekeeping related code to its own file"
Previous message: Will Deacon: "Re: [RFC 1/3] perf tool: Introduce arch-specific supplemental perf open strerror capability"
In reply to: Frederic Weisbecker: "[PATCH 01/12] housekeeping: Move housekeeping related code to its own file"
Next in thread: tip-bot for Frederic Weisbecker: "[tip:sched/core] housekeeping: Move housekeeping related code to its own file"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

On Tue, Oct 24, 2017 at 03:06:50PM +0200, Frederic Weisbecker wrote:
> The housekeeping code is currently tied to the nohz code. As we are
> planning to make housekeeping independant from it, start with moving
> the relevant code to its own file.
>
> Signed-off-by: Frederic Weisbecker <frederic@xxxxxxxxxx>
> Cc: Chris Metcalf <cmetcalf@xxxxxxxxxxxx>
> Cc: Rik van Riel <riel@xxxxxxxxxx>
> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Cc: Mike Galbraith <efault@xxxxxx>
> Cc: Ingo Molnar <mingo@xxxxxxxxxx>
> Cc: Christoph Lameter <cl@xxxxxxxxx>
> Cc: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>

>From an RCU perspective:

Acked-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>

> Cc: Wanpeng Li <kernellwp@xxxxxxxxx>
> Cc: Luiz Capitulino <lcapitulino@xxxxxxxxxx>
> ---
> drivers/net/ethernet/tile/tilegx.c | 2 +-
> include/linux/housekeeping.h | 56 ++++++++++++++++++++++++++++++++++++++
> include/linux/tick.h | 37 -------------------------
> init/main.c | 2 ++
> kernel/Makefile | 1 +
> kernel/housekeeping.c | 33 ++++++++++++++++++++++
> kernel/rcu/tree_plugin.h | 1 +
> kernel/rcu/update.c | 1 +
> kernel/sched/core.c | 1 +
> kernel/sched/fair.c | 1 +
> kernel/time/tick-sched.c | 18 ------------
> kernel/watchdog.c | 1 +
> 12 files changed, 98 insertions(+), 56 deletions(-)
> create mode 100644 include/linux/housekeeping.h
> create mode 100644 kernel/housekeeping.c
>
> diff --git a/drivers/net/ethernet/tile/tilegx.c b/drivers/net/ethernet/tile/tilegx.c
> index c00102b..8c7ef12 100644
> --- a/drivers/net/ethernet/tile/tilegx.c
> +++ b/drivers/net/ethernet/tile/tilegx.c
> @@ -40,7 +40,7 @@
> #include <linux/tcp.h>
> #include <linux/net_tstamp.h>
> #include <linux/ptp_clock_kernel.h>
> -#include <linux/tick.h>
> +#include <linux/housekeeping.h>
>
> #include <asm/checksum.h>
> #include <asm/homecache.h>
> diff --git a/include/linux/housekeeping.h b/include/linux/housekeeping.h
> new file mode 100644
> index 0000000..3d6a8e6
> --- /dev/null
> +++ b/include/linux/housekeeping.h
> @@ -0,0 +1,56 @@
> +#ifndef _LINUX_HOUSEKEEPING_H
> +#define _LINUX_HOUSEKEEPING_H
> +
> +#include <linux/cpumask.h>
> +#include <linux/init.h>
> +#include <linux/tick.h>
> +
> +#ifdef CONFIG_NO_HZ_FULL
> +extern cpumask_var_t housekeeping_mask;
> +
> +static inline int housekeeping_any_cpu(void)
> +{
> + return cpumask_any_and(housekeeping_mask, cpu_online_mask);
> +}
> +
> +extern void __init housekeeping_init(void);
> +
> +#else
> +
> +static inline int housekeeping_any_cpu(void)
> +{
> + return smp_processor_id();
> +}
> +
> +static inline void housekeeping_init(void) { }
> +#endif /* CONFIG_NO_HZ_FULL */
> +
> +
> +static inline const struct cpumask *housekeeping_cpumask(void)
> +{
> +#ifdef CONFIG_NO_HZ_FULL
> + if (tick_nohz_full_enabled())
> + return housekeeping_mask;
> +#endif
> + return cpu_possible_mask;
> +}
> +
> +static inline bool is_housekeeping_cpu(int cpu)
> +{
> +#ifdef CONFIG_NO_HZ_FULL
> + if (tick_nohz_full_enabled())
> + return cpumask_test_cpu(cpu, housekeeping_mask);
> +#endif
> + return true;
> +}
> +
> +static inline void housekeeping_affine(struct task_struct *t)
> +{
> +#ifdef CONFIG_NO_HZ_FULL
> + if (tick_nohz_full_enabled())
> + set_cpus_allowed_ptr(t, housekeeping_mask);
> +
> +#endif
> +}
> +
> +#endif /* _LINUX_HOUSEKEEPING_H */
> diff --git a/include/linux/tick.h b/include/linux/tick.h
> index fe01e68..68afc09 100644
> --- a/include/linux/tick.h
> +++ b/include/linux/tick.h
> @@ -137,7 +137,6 @@ static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
> #ifdef CONFIG_NO_HZ_FULL
> extern bool tick_nohz_full_running;
> extern cpumask_var_t tick_nohz_full_mask;
> -extern cpumask_var_t housekeeping_mask;
>
> static inline bool tick_nohz_full_enabled(void)
> {
> @@ -161,11 +160,6 @@ static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
> cpumask_or(mask, mask, tick_nohz_full_mask);
> }
>
> -static inline int housekeeping_any_cpu(void)
> -{
> - return cpumask_any_and(housekeeping_mask, cpu_online_mask);
> -}
> -
> extern void tick_nohz_dep_set(enum tick_dep_bits bit);
> extern void tick_nohz_dep_clear(enum tick_dep_bits bit);
> extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit);
> @@ -235,10 +229,6 @@ static inline void tick_dep_clear_signal(struct signal_struct *signal,
> extern void tick_nohz_full_kick_cpu(int cpu);
> extern void __tick_nohz_task_switch(void);
> #else
> -static inline int housekeeping_any_cpu(void)
> -{
> - return smp_processor_id();
> -}
> static inline bool tick_nohz_full_enabled(void) { return false; }
> static inline bool tick_nohz_full_cpu(int cpu) { return false; }
> static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
> @@ -260,33 +250,6 @@ static inline void tick_nohz_full_kick_cpu(int cpu) { }
> static inline void __tick_nohz_task_switch(void) { }
> #endif
>
> -static inline const struct cpumask *housekeeping_cpumask(void)
> -{
> -#ifdef CONFIG_NO_HZ_FULL
> - if (tick_nohz_full_enabled())
> - return housekeeping_mask;
> -#endif
> - return cpu_possible_mask;
> -}
> -
> -static inline bool is_housekeeping_cpu(int cpu)
> -{
> -#ifdef CONFIG_NO_HZ_FULL
> - if (tick_nohz_full_enabled())
> - return cpumask_test_cpu(cpu, housekeeping_mask);
> -#endif
> - return true;
> -}
> -
> -static inline void housekeeping_affine(struct task_struct *t)
> -{
> -#ifdef CONFIG_NO_HZ_FULL
> - if (tick_nohz_full_enabled())
> - set_cpus_allowed_ptr(t, housekeeping_mask);
> -
> -#endif
> -}
> -
> static inline void tick_nohz_task_switch(void)
> {
> if (tick_nohz_full_enabled())
> diff --git a/init/main.c b/init/main.c
> index 0ee9c686..bf138b9 100644
> --- a/init/main.c
> +++ b/init/main.c
> @@ -46,6 +46,7 @@
> #include <linux/cgroup.h>
> #include <linux/efi.h>
> #include <linux/tick.h>
> +#include <linux/housekeeping.h>
> #include <linux/interrupt.h>
> #include <linux/taskstats_kern.h>
> #include <linux/delayacct.h>
> @@ -606,6 +607,7 @@ asmlinkage __visible void __init start_kernel(void)
> early_irq_init();
> init_IRQ();
> tick_init();
> + housekeeping_init();
> rcu_init_nohz();
> init_timers();
> hrtimers_init();
> diff --git a/kernel/Makefile b/kernel/Makefile
> index ed470aa..c63f893 100644
> --- a/kernel/Makefile
> +++ b/kernel/Makefile
> @@ -109,6 +109,7 @@ obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
> obj-$(CONFIG_JUMP_LABEL) += jump_label.o
> obj-$(CONFIG_CONTEXT_TRACKING) += context_tracking.o
> obj-$(CONFIG_TORTURE_TEST) += torture.o
> +obj-$(CONFIG_NO_HZ_FULL) += housekeeping.o
>
> obj-$(CONFIG_HAS_IOMEM) += memremap.o
>
> diff --git a/kernel/housekeeping.c b/kernel/housekeeping.c
> new file mode 100644
> index 0000000..b41c52e
> --- /dev/null
> +++ b/kernel/housekeeping.c
> @@ -0,0 +1,33 @@
> +/*
> + * Housekeeping management. Manage the targets for routine code that can run on
> + * any CPU: unbound workqueues, timers, kthreads and any offloadable work.
> + *
> + * Copyright (C) 2017 Red Hat, Inc., Frederic Weisbecker
> + *
> + */
> +
> +#include <linux/housekeeping.h>
> +#include <linux/tick.h>
> +#include <linux/init.h>
> +#include <linux/kernel.h>
> +
> +cpumask_var_t housekeeping_mask;
> +
> +void __init housekeeping_init(void)
> +{
> + if (!tick_nohz_full_enabled())
> + return;
> +
> + if (!alloc_cpumask_var(&housekeeping_mask, GFP_KERNEL)) {
> + WARN(1, "NO_HZ: Can't allocate not-full dynticks cpumask\n");
> + cpumask_clear(tick_nohz_full_mask);
> + tick_nohz_full_running = false;
> + return;
> + }
> +
> + cpumask_andnot(housekeeping_mask,
> + cpu_possible_mask, tick_nohz_full_mask);
> +
> + /* We need at least one CPU to handle housekeeping work */
> + WARN_ON_ONCE(cpumask_empty(housekeeping_mask));
> +}
> diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
> index e012b9b..387e0a2 100644
> --- a/kernel/rcu/tree_plugin.h
> +++ b/kernel/rcu/tree_plugin.h
> @@ -29,6 +29,7 @@
> #include <linux/oom.h>
> #include <linux/sched/debug.h>
> #include <linux/smpboot.h>
> +#include <linux/housekeeping.h>
> #include <uapi/linux/sched/types.h>
> #include "../time/tick-internal.h"
>
> diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
> index 5033b66..1c003e2 100644
> --- a/kernel/rcu/update.c
> +++ b/kernel/rcu/update.c
> @@ -51,6 +51,7 @@
> #include <linux/kthread.h>
> #include <linux/tick.h>
> #include <linux/rcupdate_wait.h>
> +#include <linux/housekeeping.h>
>
> #define CREATE_TRACE_POINTS
>
> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index d17c5da..4cc01a7 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -26,6 +26,7 @@
> #include <linux/profile.h>
> #include <linux/security.h>
> #include <linux/syscalls.h>
> +#include <linux/housekeeping.h>
>
> #include <asm/switch_to.h>
> #include <asm/tlb.h>
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index d3f3094..c76fab6 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -32,6 +32,7 @@
> #include <linux/mempolicy.h>
> #include <linux/migrate.h>
> #include <linux/task_work.h>
> +#include <linux/housekeeping.h>
>
> #include <trace/events/sched.h>
>
> diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
> index c7a899c..9d29dee 100644
> --- a/kernel/time/tick-sched.c
> +++ b/kernel/time/tick-sched.c
> @@ -165,7 +165,6 @@ static void tick_sched_handle(struct tick_sched *ts, struct pt_regs *regs)
>
> #ifdef CONFIG_NO_HZ_FULL
> cpumask_var_t tick_nohz_full_mask;
> -cpumask_var_t housekeeping_mask;
> bool tick_nohz_full_running;
> static atomic_t tick_dep_mask;
>
> @@ -437,13 +436,6 @@ void __init tick_nohz_init(void)
> return;
> }
>
> - if (!alloc_cpumask_var(&housekeeping_mask, GFP_KERNEL)) {
> - WARN(1, "NO_HZ: Can't allocate not-full dynticks cpumask\n");
> - cpumask_clear(tick_nohz_full_mask);
> - tick_nohz_full_running = false;
> - return;
> - }
> -
> /*
> * Full dynticks uses irq work to drive the tick rescheduling on safe
> * locking contexts. But then we need irq work to raise its own
> @@ -452,7 +444,6 @@ void __init tick_nohz_init(void)
> if (!arch_irq_work_has_interrupt()) {
> pr_warn("NO_HZ: Can't run full dynticks because arch doesn't support irq work self-IPIs\n");
> cpumask_clear(tick_nohz_full_mask);
> - cpumask_copy(housekeeping_mask, cpu_possible_mask);
> tick_nohz_full_running = false;
> return;
> }
> @@ -465,9 +456,6 @@ void __init tick_nohz_init(void)
> cpumask_clear_cpu(cpu, tick_nohz_full_mask);
> }
>
> - cpumask_andnot(housekeeping_mask,
> - cpu_possible_mask, tick_nohz_full_mask);
> -
> for_each_cpu(cpu, tick_nohz_full_mask)
> context_tracking_cpu_set(cpu);
>
> @@ -477,12 +465,6 @@ void __init tick_nohz_init(void)
> WARN_ON(ret < 0);
> pr_info("NO_HZ: Full dynticks CPUs: %*pbl.\n",
> cpumask_pr_args(tick_nohz_full_mask));
> -
> - /*
> - * We need at least one CPU to handle housekeeping work such
> - * as timekeeping, unbound timers, workqueues, ...
> - */
> - WARN_ON_ONCE(cpumask_empty(housekeeping_mask));
> }
> #endif
>
> diff --git a/kernel/watchdog.c b/kernel/watchdog.c
> index 6bcb854..d71eee0 100644
> --- a/kernel/watchdog.c
> +++ b/kernel/watchdog.c
> @@ -24,6 +24,7 @@
> #include <linux/workqueue.h>
> #include <linux/sched/clock.h>
> #include <linux/sched/debug.h>
> +#include <linux/housekeeping.h>
>
> #include <asm/irq_regs.h>
> #include <linux/kvm_para.h>
> --
> 2.7.4
>

Next message: Frederic Weisbecker: "[PATCH 01/12] housekeeping: Move housekeeping related code to its own file"
Previous message: Will Deacon: "Re: [RFC 1/3] perf tool: Introduce arch-specific supplemental perf open strerror capability"
In reply to: Frederic Weisbecker: "[PATCH 01/12] housekeeping: Move housekeeping related code to its own file"
Next in thread: tip-bot for Frederic Weisbecker: "[tip:sched/core] housekeeping: Move housekeeping related code to its own file"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]