github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-23 14:42:08 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

x86/resctrl: Allow overflow/limbo handlers to be scheduled on any-but CPU

Browse Source 
When a CPU is taken offline resctrl may need to move the overflow or limbo
handlers to run on a different CPU.

Once the offline callbacks have been split, cqm_setup_limbo_handler() will be
called while the CPU that is going offline is still present in the CPU mask.

Pass the CPU to exclude to cqm_setup_limbo_handler() and
mbm_setup_overflow_handler(). These functions can use a variant of
cpumask_any_but() when selecting the CPU. -1 is used to indicate no CPUs need
excluding.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Link: https://lore.kernel.org/r/20240213184438.16675-22-james.morse@arm.com
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
This commit is contained in:
James Morse 2024-02-13 18:44:35 +00:00 committed by Borislav Petkov (AMD)
parent 1b3e50ce7f
commit 978fcca954
6 changed files with 72 additions and 21 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
arch/x86/kernel/cpu/resctrl/core.c
View File

@ -584,12 +584,16 @@ static void domain_remove_cpu(int cpu, struct rdt_resource *r)
if (r == &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl) {
if (is_mbm_enabled() && cpu == d->mbm_work_cpu) {
cancel_delayed_work(&d->mbm_over);
mbm_setup_overflow_handler(d, 0);
/*
* temporary: exclude_cpu=-1 as this CPU has already
* been removed by cpumask_clear_cpu()d
*/
mbm_setup_overflow_handler(d, 0, RESCTRL_PICK_ANY_CPU);
}
if (is_llc_occupancy_enabled() && cpu == d->cqm_work_cpu &&
has_busy_rmid(d)) {
cancel_delayed_work(&d->cqm_limbo);
cqm_setup_limbo_handler(d, 0);
cqm_setup_limbo_handler(d, 0, RESCTRL_PICK_ANY_CPU);
}
}
}

2
arch/x86/kernel/cpu/resctrl/ctrlmondata.c
View File

@ -552,7 +552,7 @@ void mon_event_read(struct rmid_read *rr, struct rdt_resource *r,
return;
}
cpu = cpumask_any_housekeeping(&d->cpu_mask);
cpu = cpumask_any_housekeeping(&d->cpu_mask, RESCTRL_PICK_ANY_CPU);
/*
* cpumask_any_housekeeping() prefers housekeeping CPUs, but

33
arch/x86/kernel/cpu/resctrl/internal.h
View File

@ -60,19 +60,36 @@
* cpumask_any_housekeeping() - Choose any CPU in @mask, preferring those that
* aren't marked nohz_full
* @mask: The mask to pick a CPU from.
* @exclude_cpu:The CPU to avoid picking.
*
* Returns a CPU in @mask. If there are housekeeping CPUs that don't use
* nohz_full, these are preferred.
* Returns a CPU from @mask, but not @exclude_cpu. If there are housekeeping
* CPUs that don't use nohz_full, these are preferred. Pass
* RESCTRL_PICK_ANY_CPU to avoid excluding any CPUs.
*
* When a CPU is excluded, returns >= nr_cpu_ids if no CPUs are available.
*/
static inline unsigned int cpumask_any_housekeeping(const struct cpumask *mask)
static inline unsigned int
cpumask_any_housekeeping(const struct cpumask *mask, int exclude_cpu)
{
unsigned int cpu, hk_cpu;
cpu = cpumask_any(mask);
if (!tick_nohz_full_cpu(cpu))
if (exclude_cpu == RESCTRL_PICK_ANY_CPU)
cpu = cpumask_any(mask);
else
cpu = cpumask_any_but(mask, exclude_cpu);
if (!IS_ENABLED(CONFIG_NO_HZ_FULL))
return cpu;
/* If the CPU picked isn't marked nohz_full nothing more needs doing. */
if (cpu < nr_cpu_ids && !tick_nohz_full_cpu(cpu))
return cpu;
/* Try to find a CPU that isn't nohz_full to use in preference */
hk_cpu = cpumask_nth_andnot(0, mask, tick_nohz_full_mask);
if (hk_cpu == exclude_cpu)
hk_cpu = cpumask_nth_andnot(1, mask, tick_nohz_full_mask);
if (hk_cpu < nr_cpu_ids)
cpu = hk_cpu;
@ -573,11 +590,13 @@ void mon_event_read(struct rmid_read *rr, struct rdt_resource *r,
struct rdt_domain *d, struct rdtgroup *rdtgrp,
int evtid, int first);
void mbm_setup_overflow_handler(struct rdt_domain *dom,
unsigned long delay_ms);
unsigned long delay_ms,
int exclude_cpu);
void mbm_handle_overflow(struct work_struct *work);
void __init intel_rdt_mbm_apply_quirk(void);
bool is_mba_sc(struct rdt_resource *r);
void cqm_setup_limbo_handler(struct rdt_domain *dom, unsigned long delay_ms);
void cqm_setup_limbo_handler(struct rdt_domain *dom, unsigned long delay_ms,
int exclude_cpu);
void cqm_handle_limbo(struct work_struct *work);
bool has_busy_rmid(struct rdt_domain *d);
void __check_limbo(struct rdt_domain *d, bool force_free);

42
arch/x86/kernel/cpu/resctrl/monitor.c
View File

@ -481,7 +481,8 @@ static void add_rmid_to_limbo(struct rmid_entry *entry)
* setup up the limbo worker.
*/
if (!has_busy_rmid(d))
cqm_setup_limbo_handler(d, CQM_LIMBOCHECK_INTERVAL);
cqm_setup_limbo_handler(d, CQM_LIMBOCHECK_INTERVAL,
RESCTRL_PICK_ANY_CPU);
set_bit(idx, d->rmid_busy_llc);
entry->busy++;
}
@ -784,7 +785,8 @@ void cqm_handle_limbo(struct work_struct *work)
__check_limbo(d, false);
if (has_busy_rmid(d)) {
d->cqm_work_cpu = cpumask_any_housekeeping(&d->cpu_mask);
d->cqm_work_cpu = cpumask_any_housekeeping(&d->cpu_mask,
RESCTRL_PICK_ANY_CPU);
schedule_delayed_work_on(d->cqm_work_cpu, &d->cqm_limbo,
delay);
}
@ -792,15 +794,25 @@ void cqm_handle_limbo(struct work_struct *work)
mutex_unlock(&rdtgroup_mutex);
}
void cqm_setup_limbo_handler(struct rdt_domain *dom, unsigned long delay_ms)
/**
* cqm_setup_limbo_handler() - Schedule the limbo handler to run for this
* domain.
* @dom: The domain the limbo handler should run for.
* @delay_ms: How far in the future the handler should run.
* @exclude_cpu: Which CPU the handler should not run on,
* RESCTRL_PICK_ANY_CPU to pick any CPU.
*/
void cqm_setup_limbo_handler(struct rdt_domain *dom, unsigned long delay_ms,
int exclude_cpu)
{
unsigned long delay = msecs_to_jiffies(delay_ms);
int cpu;
cpu = cpumask_any_housekeeping(&dom->cpu_mask);
cpu = cpumask_any_housekeeping(&dom->cpu_mask, exclude_cpu);
dom->cqm_work_cpu = cpu;
schedule_delayed_work_on(cpu, &dom->cqm_limbo, delay);
if (cpu < nr_cpu_ids)
schedule_delayed_work_on(cpu, &dom->cqm_limbo, delay);
}
void mbm_handle_overflow(struct work_struct *work)
@ -838,14 +850,24 @@ void mbm_handle_overflow(struct work_struct *work)
* Re-check for housekeeping CPUs. This allows the overflow handler to
* move off a nohz_full CPU quickly.
*/
d->mbm_work_cpu = cpumask_any_housekeeping(&d->cpu_mask);
d->mbm_work_cpu = cpumask_any_housekeeping(&d->cpu_mask,
RESCTRL_PICK_ANY_CPU);
schedule_delayed_work_on(d->mbm_work_cpu, &d->mbm_over, delay);
out_unlock:
mutex_unlock(&rdtgroup_mutex);
}
void mbm_setup_overflow_handler(struct rdt_domain *dom, unsigned long delay_ms)
/**
* mbm_setup_overflow_handler() - Schedule the overflow handler to run for this
* domain.
* @dom: The domain the overflow handler should run for.
* @delay_ms: How far in the future the handler should run.
* @exclude_cpu: Which CPU the handler should not run on,
* RESCTRL_PICK_ANY_CPU to pick any CPU.
*/
void mbm_setup_overflow_handler(struct rdt_domain *dom, unsigned long delay_ms,
int exclude_cpu)
{
unsigned long delay = msecs_to_jiffies(delay_ms);
int cpu;
@ -856,9 +878,11 @@ void mbm_setup_overflow_handler(struct rdt_domain *dom, unsigned long delay_ms)
*/
if (!resctrl_mounted || !resctrl_arch_mon_capable())
return;
cpu = cpumask_any_housekeeping(&dom->cpu_mask);
cpu = cpumask_any_housekeeping(&dom->cpu_mask, exclude_cpu);
dom->mbm_work_cpu = cpu;
schedule_delayed_work_on(cpu, &dom->mbm_over, delay);
if (cpu < nr_cpu_ids)
schedule_delayed_work_on(cpu, &dom->mbm_over, delay);
}
static int dom_data_init(struct rdt_resource *r)

6
arch/x86/kernel/cpu/resctrl/rdtgroup.c
View File

@ -2678,7 +2678,8 @@ static int rdt_get_tree(struct fs_context *fc)
if (is_mbm_enabled()) {
r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
list_for_each_entry(dom, &r->domains, list)
mbm_setup_overflow_handler(dom, MBM_OVERFLOW_INTERVAL);
mbm_setup_overflow_handler(dom, MBM_OVERFLOW_INTERVAL,
RESCTRL_PICK_ANY_CPU);
}
goto out;
@ -3989,7 +3990,8 @@ int resctrl_online_domain(struct rdt_resource *r, struct rdt_domain *d)
if (is_mbm_enabled()) {
INIT_DELAYED_WORK(&d->mbm_over, mbm_handle_overflow);
mbm_setup_overflow_handler(d, MBM_OVERFLOW_INTERVAL);
mbm_setup_overflow_handler(d, MBM_OVERFLOW_INTERVAL,
RESCTRL_PICK_ANY_CPU);
}
if (is_llc_occupancy_enabled())

2
include/linux/resctrl.h
View File

@ -10,6 +10,8 @@
#define RESCTRL_RESERVED_CLOSID 0
#define RESCTRL_RESERVED_RMID 0
#define RESCTRL_PICK_ANY_CPU -1
#ifdef CONFIG_PROC_CPU_RESCTRL
int proc_resctrl_show(struct seq_file *m,