On 1/26/24 15:23, Andrew Jones wrote:
> Now that the previous patches have cleaned up Arm's on_cpus
> implementation we can move it to the common lib where riscv
> will share it.
>
> Signed-off-by: Andrew Jones <andrew.jones@xxxxxxxxx>
> Acked-by: Thomas Huth <thuth@xxxxxxxxxx>
Reviewed-by: Eric Auger <eric.auger@xxxxxxxxxx>
Eric
> ---
> arm/Makefile.common | 1 +
> lib/arm/asm/smp.h | 8 +--
> lib/arm/smp.c | 144 -----------------------------------------
> lib/on-cpus.c | 154 ++++++++++++++++++++++++++++++++++++++++++++
> lib/on-cpus.h | 14 ++++
> 5 files changed, 170 insertions(+), 151 deletions(-)
> create mode 100644 lib/on-cpus.c
> create mode 100644 lib/on-cpus.h
>
> diff --git a/arm/Makefile.common b/arm/Makefile.common
> index 5214c8acdab3..dc92a7433350 100644
> --- a/arm/Makefile.common
> +++ b/arm/Makefile.common
> @@ -43,6 +43,7 @@ cflatobjs += lib/vmalloc.o
> cflatobjs += lib/alloc.o
> cflatobjs += lib/devicetree.o
> cflatobjs += lib/migrate.o
> +cflatobjs += lib/on-cpus.o
> cflatobjs += lib/pci.o
> cflatobjs += lib/pci-host-generic.o
> cflatobjs += lib/pci-testdev.o
> diff --git a/lib/arm/asm/smp.h b/lib/arm/asm/smp.h
> index f0c0f97a19f8..2e1dc27f7bd8 100644
> --- a/lib/arm/asm/smp.h
> +++ b/lib/arm/asm/smp.h
> @@ -6,6 +6,7 @@
> * This work is licensed under the terms of the GNU LGPL, version 2.
> */
> #include <cpumask.h>
> +#include <on-cpus.h>
> #include <asm/barrier.h>
> #include <asm/thread_info.h>
>
> @@ -22,14 +23,7 @@ extern struct secondary_data secondary_data;
> #define smp_wait_for_event() wfe()
> #define smp_send_event() sev()
>
> -extern bool cpu0_calls_idle;
> -
> extern void halt(void);
> -extern void do_idle(void);
> -
> -extern void on_cpu_async(int cpu, void (*func)(void *data), void *data);
> -extern void on_cpu(int cpu, void (*func)(void *data), void *data);
> -extern void on_cpus(void (*func)(void *data), void *data);
>
> extern void smp_boot_secondary(int cpu, secondary_entry_fn entry);
> extern void smp_boot_secondary_nofail(int cpu, secondary_entry_fn entry);
> diff --git a/lib/arm/smp.c b/lib/arm/smp.c
> index e0872a1a72c2..0207ca2a7d57 100644
> --- a/lib/arm/smp.c
> +++ b/lib/arm/smp.c
> @@ -10,13 +10,10 @@
> #include <cpumask.h>
> #include <asm/thread_info.h>
> #include <asm/spinlock.h>
> -#include <asm/barrier.h>
> #include <asm/mmu.h>
> #include <asm/psci.h>
> #include <asm/smp.h>
>
> -bool cpu0_calls_idle;
> -
> cpumask_t cpu_present_mask;
> cpumask_t cpu_online_mask;
> cpumask_t cpu_idle_mask;
> @@ -83,144 +80,3 @@ void smp_boot_secondary_nofail(int cpu, secondary_entry_fn entry)
> __smp_boot_secondary(cpu, entry);
> spin_unlock(&lock);
> }
> -
> -struct on_cpu_info {
> - void (*func)(void *data);
> - void *data;
> - cpumask_t waiters;
> -};
> -static struct on_cpu_info on_cpu_info[NR_CPUS];
> -static cpumask_t on_cpu_info_lock;
> -
> -static bool get_on_cpu_info(int cpu)
> -{
> - return !cpumask_test_and_set_cpu(cpu, &on_cpu_info_lock);
> -}
> -
> -static void put_on_cpu_info(int cpu)
> -{
> - int ret = cpumask_test_and_clear_cpu(cpu, &on_cpu_info_lock);
> - assert(ret);
> -}
> -
> -static void __deadlock_check(int cpu, const cpumask_t *waiters, bool *found)
> -{
> - int i;
> -
> - for_each_cpu(i, waiters) {
> - if (i == cpu) {
> - printf("CPU%d", cpu);
> - *found = true;
> - return;
> - }
> - __deadlock_check(cpu, &on_cpu_info[i].waiters, found);
> - if (*found) {
> - printf(" <=> CPU%d", i);
> - return;
> - }
> - }
> -}
> -
> -static void deadlock_check(int me, int cpu)
> -{
> - bool found = false;
> -
> - __deadlock_check(cpu, &on_cpu_info[me].waiters, &found);
> - if (found) {
> - printf(" <=> CPU%d deadlock detectd\n", me);
> - assert(0);
> - }
> -}
> -
> -static void cpu_wait(int cpu)
> -{
> - int me = smp_processor_id();
> -
> - if (cpu == me)
> - return;
> -
> - cpumask_set_cpu(me, &on_cpu_info[cpu].waiters);
> - deadlock_check(me, cpu);
> - while (!cpu_idle(cpu))
> - smp_wait_for_event();
> - cpumask_clear_cpu(me, &on_cpu_info[cpu].waiters);
> -}
> -
> -void do_idle(void)
> -{
> - int cpu = smp_processor_id();
> -
> - if (cpu == 0)
> - cpu0_calls_idle = true;
> -
> - set_cpu_idle(cpu, true);
> - smp_send_event();
> -
> - for (;;) {
> - while (cpu_idle(cpu))
> - smp_wait_for_event();
> - smp_rmb();
> - on_cpu_info[cpu].func(on_cpu_info[cpu].data);
> - on_cpu_info[cpu].func = NULL;
> - smp_wmb();
> - set_cpu_idle(cpu, true);
> - smp_send_event();
> - }
> -}
> -
> -void on_cpu_async(int cpu, void (*func)(void *data), void *data)
> -{
> - if (cpu == smp_processor_id()) {
> - func(data);
> - return;
> - }
> -
> - assert_msg(cpu != 0 || cpu0_calls_idle, "Waiting on CPU0, which is unlikely to idle. "
> - "If this is intended set cpu0_calls_idle=1");
> -
> - smp_boot_secondary_nofail(cpu, do_idle);
> -
> - for (;;) {
> - cpu_wait(cpu);
> - if (get_on_cpu_info(cpu)) {
> - if ((volatile void *)on_cpu_info[cpu].func == NULL)
> - break;
> - put_on_cpu_info(cpu);
> - }
> - }
> -
> - on_cpu_info[cpu].func = func;
> - on_cpu_info[cpu].data = data;
> - set_cpu_idle(cpu, false);
> - put_on_cpu_info(cpu);
> - smp_send_event();
> -}
> -
> -void on_cpu(int cpu, void (*func)(void *data), void *data)
> -{
> - on_cpu_async(cpu, func, data);
> - cpu_wait(cpu);
> -}
> -
> -void on_cpus(void (*func)(void *data), void *data)
> -{
> - int cpu, me = smp_processor_id();
> -
> - for_each_present_cpu(cpu) {
> - if (cpu == me)
> - continue;
> - on_cpu_async(cpu, func, data);
> - }
> - func(data);
> -
> - for_each_present_cpu(cpu) {
> - if (cpu == me)
> - continue;
> - cpumask_set_cpu(me, &on_cpu_info[cpu].waiters);
> - deadlock_check(me, cpu);
> - }
> - while (cpumask_weight(&cpu_idle_mask) < nr_cpus - 1)
> - smp_wait_for_event();
> - for_each_present_cpu(cpu)
> - cpumask_clear_cpu(me, &on_cpu_info[cpu].waiters);
> -}
> diff --git a/lib/on-cpus.c b/lib/on-cpus.c
> new file mode 100644
> index 000000000000..aed70f7b27b2
> --- /dev/null
> +++ b/lib/on-cpus.c
> @@ -0,0 +1,154 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * on_cpus() support based on cpumasks.
> + *
> + * Copyright (C) 2015, Red Hat Inc, Andrew Jones <drjones@xxxxxxxxxx>
> + */
> +#include <libcflat.h>
> +#include <cpumask.h>
> +#include <on-cpus.h>
> +#include <asm/barrier.h>
> +#include <asm/smp.h>
> +
> +bool cpu0_calls_idle;
> +
> +struct on_cpu_info {
> + void (*func)(void *data);
> + void *data;
> + cpumask_t waiters;
> +};
> +static struct on_cpu_info on_cpu_info[NR_CPUS];
> +static cpumask_t on_cpu_info_lock;
> +
> +static bool get_on_cpu_info(int cpu)
> +{
> + return !cpumask_test_and_set_cpu(cpu, &on_cpu_info_lock);
> +}
> +
> +static void put_on_cpu_info(int cpu)
> +{
> + int ret = cpumask_test_and_clear_cpu(cpu, &on_cpu_info_lock);
> + assert(ret);
> +}
> +
> +static void __deadlock_check(int cpu, const cpumask_t *waiters, bool *found)
> +{
> + int i;
> +
> + for_each_cpu(i, waiters) {
> + if (i == cpu) {
> + printf("CPU%d", cpu);
> + *found = true;
> + return;
> + }
> + __deadlock_check(cpu, &on_cpu_info[i].waiters, found);
> + if (*found) {
> + printf(" <=> CPU%d", i);
> + return;
> + }
> + }
> +}
> +
> +static void deadlock_check(int me, int cpu)
> +{
> + bool found = false;
> +
> + __deadlock_check(cpu, &on_cpu_info[me].waiters, &found);
> + if (found) {
> + printf(" <=> CPU%d deadlock detectd\n", me);
> + assert(0);
> + }
> +}
> +
> +static void cpu_wait(int cpu)
> +{
> + int me = smp_processor_id();
> +
> + if (cpu == me)
> + return;
> +
> + cpumask_set_cpu(me, &on_cpu_info[cpu].waiters);
> + deadlock_check(me, cpu);
> + while (!cpu_idle(cpu))
> + smp_wait_for_event();
> + cpumask_clear_cpu(me, &on_cpu_info[cpu].waiters);
> +}
> +
> +void do_idle(void)
> +{
> + int cpu = smp_processor_id();
> +
> + if (cpu == 0)
> + cpu0_calls_idle = true;
> +
> + set_cpu_idle(cpu, true);
> + smp_send_event();
> +
> + for (;;) {
> + while (cpu_idle(cpu))
> + smp_wait_for_event();
> + smp_rmb();
> + on_cpu_info[cpu].func(on_cpu_info[cpu].data);
> + on_cpu_info[cpu].func = NULL;
> + smp_wmb();
> + set_cpu_idle(cpu, true);
> + smp_send_event();
> + }
> +}
> +
> +void on_cpu_async(int cpu, void (*func)(void *data), void *data)
> +{
> + if (cpu == smp_processor_id()) {
> + func(data);
> + return;
> + }
> +
> + assert_msg(cpu != 0 || cpu0_calls_idle, "Waiting on CPU0, which is unlikely to idle. "
> + "If this is intended set cpu0_calls_idle=1");
> +
> + smp_boot_secondary_nofail(cpu, do_idle);
> +
> + for (;;) {
> + cpu_wait(cpu);
> + if (get_on_cpu_info(cpu)) {
> + if ((volatile void *)on_cpu_info[cpu].func == NULL)
> + break;
> + put_on_cpu_info(cpu);
> + }
> + }
> +
> + on_cpu_info[cpu].func = func;
> + on_cpu_info[cpu].data = data;
> + set_cpu_idle(cpu, false);
> + put_on_cpu_info(cpu);
> + smp_send_event();
> +}
> +
> +void on_cpu(int cpu, void (*func)(void *data), void *data)
> +{
> + on_cpu_async(cpu, func, data);
> + cpu_wait(cpu);
> +}
> +
> +void on_cpus(void (*func)(void *data), void *data)
> +{
> + int cpu, me = smp_processor_id();
> +
> + for_each_present_cpu(cpu) {
> + if (cpu == me)
> + continue;
> + on_cpu_async(cpu, func, data);
> + }
> + func(data);
> +
> + for_each_present_cpu(cpu) {
> + if (cpu == me)
> + continue;
> + cpumask_set_cpu(me, &on_cpu_info[cpu].waiters);
> + deadlock_check(me, cpu);
> + }
> + while (cpumask_weight(&cpu_idle_mask) < nr_cpus - 1)
> + smp_wait_for_event();
> + for_each_present_cpu(cpu)
> + cpumask_clear_cpu(me, &on_cpu_info[cpu].waiters);
> +}
> diff --git a/lib/on-cpus.h b/lib/on-cpus.h
> new file mode 100644
> index 000000000000..41103b0245c7
> --- /dev/null
> +++ b/lib/on-cpus.h
> @@ -0,0 +1,14 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +#ifndef _ON_CPUS_H_
> +#define _ON_CPUS_H_
> +#include <stdbool.h>
> +
> +extern bool cpu0_calls_idle;
> +
> +void do_idle(void);
> +
> +void on_cpu_async(int cpu, void (*func)(void *data), void *data);
> +void on_cpu(int cpu, void (*func)(void *data), void *data);
> +void on_cpus(void (*func)(void *data), void *data);
> +
> +#endif /* _ON_CPUS_H_ */
