[PATCH 05/10] sched/core: Remove the tsk_cpus_allowed() wrapper

From: Ingo Molnar
Date: Wed Feb 08 2017 - 13:37:54 EST


So the original intention of tsk_cpus_allowed() was to 'future-proof'
the field - but it's pretty ineffectual at that, because half of
the code uses ->cpus_allowed directly ...

Also, the wrapper makes the code longer than the original expression!

So just get rid of it. This also shrinks <linux/sched.h> a bit.

Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/powerpc/kernel/smp.c | 2 +-
arch/powerpc/platforms/cell/spufs/sched.c | 2 +-
arch/sparc/kernel/sysfs.c | 2 +-
drivers/cpufreq/sparc-us2e-cpufreq.c | 4 ++--
drivers/cpufreq/sparc-us3-cpufreq.c | 4 ++--
drivers/infiniband/hw/hfi1/affinity.c | 2 +-
drivers/infiniband/hw/hfi1/sdma.c | 2 +-
include/linux/sched.h | 3 ---
kernel/sched/core.c | 20 ++++++++++----------
kernel/sched/cpudeadline.c | 4 ++--
kernel/sched/cpupri.c | 4 ++--
kernel/sched/deadline.c | 7 +++----
kernel/sched/fair.c | 25 ++++++++++++-------------
kernel/sched/rt.c | 5 ++---
lib/smp_processor_id.c | 2 +-
samples/trace_events/trace-events-sample.c | 2 +-
16 files changed, 42 insertions(+), 48 deletions(-)

diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index 893bd7f79be6..b7d8f867742d 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -795,7 +795,7 @@ void __init smp_cpus_done(unsigned int max_cpus)
* se we pin us down to CPU 0 for a short while
*/
alloc_cpumask_var(&old_mask, GFP_NOWAIT);
- cpumask_copy(old_mask, tsk_cpus_allowed(current));
+ cpumask_copy(old_mask, &current->cpus_allowed);
set_cpus_allowed_ptr(current, cpumask_of(boot_cpuid));

if (smp_ops && smp_ops->setup_cpu)
diff --git a/arch/powerpc/platforms/cell/spufs/sched.c b/arch/powerpc/platforms/cell/spufs/sched.c
index 460f5f31d5cb..9b543df210fb 100644
--- a/arch/powerpc/platforms/cell/spufs/sched.c
+++ b/arch/powerpc/platforms/cell/spufs/sched.c
@@ -140,7 +140,7 @@ void __spu_update_sched_info(struct spu_context *ctx)
* runqueue. The context will be rescheduled on the proper node
* if it is timesliced or preempted.
*/
- cpumask_copy(&ctx->cpus_allowed, tsk_cpus_allowed(current));
+ cpumask_copy(&ctx->cpus_allowed, &current->cpus_allowed);

/* Save the current cpu id for spu interrupt routing. */
ctx->last_ran = raw_smp_processor_id();
diff --git a/arch/sparc/kernel/sysfs.c b/arch/sparc/kernel/sysfs.c
index 4808b6d23455..d63fc613e7a9 100644
--- a/arch/sparc/kernel/sysfs.c
+++ b/arch/sparc/kernel/sysfs.c
@@ -106,7 +106,7 @@ static unsigned long run_on_cpu(unsigned long cpu,
cpumask_t old_affinity;
unsigned long ret;

- cpumask_copy(&old_affinity, tsk_cpus_allowed(current));
+ cpumask_copy(&old_affinity, &current->cpus_allowed);
/* should return -EINVAL to userspace */
if (set_cpus_allowed_ptr(current, cpumask_of(cpu)))
return 0;
diff --git a/drivers/cpufreq/sparc-us2e-cpufreq.c b/drivers/cpufreq/sparc-us2e-cpufreq.c
index b73feeb666f9..35ddb6da93aa 100644
--- a/drivers/cpufreq/sparc-us2e-cpufreq.c
+++ b/drivers/cpufreq/sparc-us2e-cpufreq.c
@@ -234,7 +234,7 @@ static unsigned int us2e_freq_get(unsigned int cpu)
cpumask_t cpus_allowed;
unsigned long clock_tick, estar;

- cpumask_copy(&cpus_allowed, tsk_cpus_allowed(current));
+ cpumask_copy(&cpus_allowed, &current->cpus_allowed);
set_cpus_allowed_ptr(current, cpumask_of(cpu));

clock_tick = sparc64_get_clock_tick(cpu) / 1000;
@@ -252,7 +252,7 @@ static int us2e_freq_target(struct cpufreq_policy *policy, unsigned int index)
unsigned long clock_tick, divisor, old_divisor, estar;
cpumask_t cpus_allowed;

- cpumask_copy(&cpus_allowed, tsk_cpus_allowed(current));
+ cpumask_copy(&cpus_allowed, &current->cpus_allowed);
set_cpus_allowed_ptr(current, cpumask_of(cpu));

new_freq = clock_tick = sparc64_get_clock_tick(cpu) / 1000;
diff --git a/drivers/cpufreq/sparc-us3-cpufreq.c b/drivers/cpufreq/sparc-us3-cpufreq.c
index 9bb42ba50efa..a8d86a449ca1 100644
--- a/drivers/cpufreq/sparc-us3-cpufreq.c
+++ b/drivers/cpufreq/sparc-us3-cpufreq.c
@@ -82,7 +82,7 @@ static unsigned int us3_freq_get(unsigned int cpu)
unsigned long reg;
unsigned int ret;

- cpumask_copy(&cpus_allowed, tsk_cpus_allowed(current));
+ cpumask_copy(&cpus_allowed, &current->cpus_allowed);
set_cpus_allowed_ptr(current, cpumask_of(cpu));

reg = read_safari_cfg();
@@ -99,7 +99,7 @@ static int us3_freq_target(struct cpufreq_policy *policy, unsigned int index)
unsigned long new_bits, new_freq, reg;
cpumask_t cpus_allowed;

- cpumask_copy(&cpus_allowed, tsk_cpus_allowed(current));
+ cpumask_copy(&cpus_allowed, &current->cpus_allowed);
set_cpus_allowed_ptr(current, cpumask_of(cpu));

new_freq = sparc64_get_clock_tick(cpu) / 1000;
diff --git a/drivers/infiniband/hw/hfi1/affinity.c b/drivers/infiniband/hw/hfi1/affinity.c
index 7a3d906b3671..e2cd2cd3b28a 100644
--- a/drivers/infiniband/hw/hfi1/affinity.c
+++ b/drivers/infiniband/hw/hfi1/affinity.c
@@ -576,7 +576,7 @@ int hfi1_get_proc_affinity(int node)
struct hfi1_affinity_node *entry;
cpumask_var_t diff, hw_thread_mask, available_mask, intrs_mask;
const struct cpumask *node_mask,
- *proc_mask = tsk_cpus_allowed(current);
+ *proc_mask = &current->cpus_allowed;
struct hfi1_affinity_node_list *affinity = &node_affinity;
struct cpu_mask_set *set = &affinity->proc;

diff --git a/drivers/infiniband/hw/hfi1/sdma.c b/drivers/infiniband/hw/hfi1/sdma.c
index 1d81cac1fa6c..5cde1ecda0fe 100644
--- a/drivers/infiniband/hw/hfi1/sdma.c
+++ b/drivers/infiniband/hw/hfi1/sdma.c
@@ -856,7 +856,7 @@ struct sdma_engine *sdma_select_user_engine(struct hfi1_devdata *dd,
{
struct sdma_rht_node *rht_node;
struct sdma_engine *sde = NULL;
- const struct cpumask *current_mask = tsk_cpus_allowed(current);
+ const struct cpumask *current_mask = &current->cpus_allowed;
unsigned long cpu_id;

/*
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 7710d52ad0c3..38af022b351d 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1999,9 +1999,6 @@ static inline struct vm_struct *task_stack_vm_area(const struct task_struct *t)
}
#endif

-/* Future-safe accessor for struct task_struct's cpus_allowed. */
-#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
-
static inline int tsk_nr_cpus_allowed(struct task_struct *p)
{
return p->nr_cpus_allowed;
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 5c010ca5b126..0706863f83b5 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -978,7 +978,7 @@ static struct rq *__migrate_task(struct rq *rq, struct task_struct *p, int dest_
return rq;

/* Affinity changed (again). */
- if (!cpumask_test_cpu(dest_cpu, tsk_cpus_allowed(p)))
+ if (!cpumask_test_cpu(dest_cpu, &p->cpus_allowed))
return rq;

rq = move_queued_task(rq, p, dest_cpu);
@@ -1255,10 +1255,10 @@ static int migrate_swap_stop(void *data)
if (task_cpu(arg->src_task) != arg->src_cpu)
goto unlock;

- if (!cpumask_test_cpu(arg->dst_cpu, tsk_cpus_allowed(arg->src_task)))
+ if (!cpumask_test_cpu(arg->dst_cpu, &arg->src_task->cpus_allowed))
goto unlock;

- if (!cpumask_test_cpu(arg->src_cpu, tsk_cpus_allowed(arg->dst_task)))
+ if (!cpumask_test_cpu(arg->src_cpu, &arg->dst_task->cpus_allowed))
goto unlock;

__migrate_swap_task(arg->src_task, arg->dst_cpu);
@@ -1299,10 +1299,10 @@ int migrate_swap(struct task_struct *cur, struct task_struct *p)
if (!cpu_active(arg.src_cpu) || !cpu_active(arg.dst_cpu))
goto out;

- if (!cpumask_test_cpu(arg.dst_cpu, tsk_cpus_allowed(arg.src_task)))
+ if (!cpumask_test_cpu(arg.dst_cpu, &arg.src_task->cpus_allowed))
goto out;

- if (!cpumask_test_cpu(arg.src_cpu, tsk_cpus_allowed(arg.dst_task)))
+ if (!cpumask_test_cpu(arg.src_cpu, &arg.dst_task->cpus_allowed))
goto out;

trace_sched_swap_numa(cur, arg.src_cpu, p, arg.dst_cpu);
@@ -1486,14 +1486,14 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
for_each_cpu(dest_cpu, nodemask) {
if (!cpu_active(dest_cpu))
continue;
- if (cpumask_test_cpu(dest_cpu, tsk_cpus_allowed(p)))
+ if (cpumask_test_cpu(dest_cpu, &p->cpus_allowed))
return dest_cpu;
}
}

for (;;) {
/* Any allowed, online CPU? */
- for_each_cpu(dest_cpu, tsk_cpus_allowed(p)) {
+ for_each_cpu(dest_cpu, &p->cpus_allowed) {
if (!(p->flags & PF_KTHREAD) && !cpu_active(dest_cpu))
continue;
if (!cpu_online(dest_cpu))
@@ -1548,7 +1548,7 @@ int select_task_rq(struct task_struct *p, int cpu, int sd_flags, int wake_flags)
if (tsk_nr_cpus_allowed(p) > 1)
cpu = p->sched_class->select_task_rq(p, cpu, sd_flags, wake_flags);
else
- cpu = cpumask_any(tsk_cpus_allowed(p));
+ cpu = cpumask_any(&p->cpus_allowed);

/*
* In order not to call set_task_cpu() on a blocking task we need
@@ -1560,7 +1560,7 @@ int select_task_rq(struct task_struct *p, int cpu, int sd_flags, int wake_flags)
* [ this allows ->select_task() to simply return task_cpu(p) and
* not worry about this generic constraint ]
*/
- if (unlikely(!cpumask_test_cpu(cpu, tsk_cpus_allowed(p)) ||
+ if (unlikely(!cpumask_test_cpu(cpu, &p->cpus_allowed) ||
!cpu_online(cpu)))
cpu = select_fallback_rq(task_cpu(p), p);

@@ -5469,7 +5469,7 @@ int migrate_task_to(struct task_struct *p, int target_cpu)
if (curr_cpu == target_cpu)
return 0;

- if (!cpumask_test_cpu(target_cpu, tsk_cpus_allowed(p)))
+ if (!cpumask_test_cpu(target_cpu, &p->cpus_allowed))
return -EINVAL;

/* TODO: This is not properly updating schedstats */
diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c
index e73119013c53..fba235c7d026 100644
--- a/kernel/sched/cpudeadline.c
+++ b/kernel/sched/cpudeadline.c
@@ -128,10 +128,10 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p,
const struct sched_dl_entity *dl_se = &p->dl;

if (later_mask &&
- cpumask_and(later_mask, cp->free_cpus, tsk_cpus_allowed(p))) {
+ cpumask_and(later_mask, cp->free_cpus, &p->cpus_allowed)) {
best_cpu = cpumask_any(later_mask);
goto out;
- } else if (cpumask_test_cpu(cpudl_maximum(cp), tsk_cpus_allowed(p)) &&
+ } else if (cpumask_test_cpu(cpudl_maximum(cp), &p->cpus_allowed) &&
dl_time_before(dl_se->deadline, cp->elements[0].dl)) {
best_cpu = cpudl_maximum(cp);
if (later_mask)
diff --git a/kernel/sched/cpupri.c b/kernel/sched/cpupri.c
index 11e9705bf937..981fcd7dc394 100644
--- a/kernel/sched/cpupri.c
+++ b/kernel/sched/cpupri.c
@@ -103,11 +103,11 @@ int cpupri_find(struct cpupri *cp, struct task_struct *p,
if (skip)
continue;

- if (cpumask_any_and(tsk_cpus_allowed(p), vec->mask) >= nr_cpu_ids)
+ if (cpumask_any_and(&p->cpus_allowed, vec->mask) >= nr_cpu_ids)
continue;

if (lowest_mask) {
- cpumask_and(lowest_mask, tsk_cpus_allowed(p), vec->mask);
+ cpumask_and(lowest_mask, &p->cpus_allowed, vec->mask);

/*
* We have to ensure that we have at least one bit
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 27737f34757d..8e4d6e4e3ccc 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -252,7 +252,7 @@ static struct rq *dl_task_offline_migration(struct rq *rq, struct task_struct *p
* If we cannot preempt any rq, fall back to pick any
* online cpu.
*/
- cpu = cpumask_any_and(cpu_active_mask, tsk_cpus_allowed(p));
+ cpu = cpumask_any_and(cpu_active_mask, &p->cpus_allowed);
if (cpu >= nr_cpu_ids) {
/*
* Fail to find any suitable cpu.
@@ -1235,7 +1235,7 @@ static void set_curr_task_dl(struct rq *rq)
static int pick_dl_task(struct rq *rq, struct task_struct *p, int cpu)
{
if (!task_running(rq, p) &&
- cpumask_test_cpu(cpu, tsk_cpus_allowed(p)))
+ cpumask_test_cpu(cpu, &p->cpus_allowed))
return 1;
return 0;
}
@@ -1384,8 +1384,7 @@ static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq)
/* Retry if something changed. */
if (double_lock_balance(rq, later_rq)) {
if (unlikely(task_rq(task) != rq ||
- !cpumask_test_cpu(later_rq->cpu,
- tsk_cpus_allowed(task)) ||
+ !cpumask_test_cpu(later_rq->cpu, &task->cpus_allowed) ||
task_running(rq, task) ||
!dl_task(task) ||
!task_on_rq_queued(task))) {
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 274c747a01ce..3b60d73ab290 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -1551,7 +1551,7 @@ static void task_numa_compare(struct task_numa_env *env,
*/
if (cur) {
/* Skip this swap candidate if cannot move to the source cpu */
- if (!cpumask_test_cpu(env->src_cpu, tsk_cpus_allowed(cur)))
+ if (!cpumask_test_cpu(env->src_cpu, &cur->cpus_allowed))
goto unlock;

/*
@@ -1661,7 +1661,7 @@ static void task_numa_find_cpu(struct task_numa_env *env,

for_each_cpu(cpu, cpumask_of_node(env->dst_nid)) {
/* Skip this CPU if the source task cannot migrate */
- if (!cpumask_test_cpu(cpu, tsk_cpus_allowed(env->p)))
+ if (!cpumask_test_cpu(cpu, &env->p->cpus_allowed))
continue;

env->dst_cpu = cpu;
@@ -5458,7 +5458,7 @@ find_idlest_group(struct sched_domain *sd, struct task_struct *p,

/* Skip over this group if it has no CPUs allowed */
if (!cpumask_intersects(sched_group_cpus(group),
- tsk_cpus_allowed(p)))
+ &p->cpus_allowed))
continue;

local_group = cpumask_test_cpu(this_cpu,
@@ -5578,7 +5578,7 @@ find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu)
return cpumask_first(sched_group_cpus(group));

/* Traverse only the allowed CPUs */
- for_each_cpu_and(i, sched_group_cpus(group), tsk_cpus_allowed(p)) {
+ for_each_cpu_and(i, sched_group_cpus(group), &p->cpus_allowed) {
if (idle_cpu(i)) {
struct rq *rq = cpu_rq(i);
struct cpuidle_state *idle = idle_get_state(rq);
@@ -5717,7 +5717,7 @@ static int select_idle_core(struct task_struct *p, struct sched_domain *sd, int
if (!test_idle_cores(target, false))
return -1;

- cpumask_and(cpus, sched_domain_span(sd), tsk_cpus_allowed(p));
+ cpumask_and(cpus, sched_domain_span(sd), &p->cpus_allowed);

for_each_cpu_wrap(core, cpus, target, wrap) {
bool idle = true;
@@ -5751,7 +5751,7 @@ static int select_idle_smt(struct task_struct *p, struct sched_domain *sd, int t
return -1;

for_each_cpu(cpu, cpu_smt_mask(target)) {
- if (!cpumask_test_cpu(cpu, tsk_cpus_allowed(p)))
+ if (!cpumask_test_cpu(cpu, &p->cpus_allowed))
continue;
if (idle_cpu(cpu))
return cpu;
@@ -5803,7 +5803,7 @@ static int select_idle_cpu(struct task_struct *p, struct sched_domain *sd, int t
time = local_clock();

for_each_cpu_wrap(cpu, sched_domain_span(sd), target, wrap) {
- if (!cpumask_test_cpu(cpu, tsk_cpus_allowed(p)))
+ if (!cpumask_test_cpu(cpu, &p->cpus_allowed))
continue;
if (idle_cpu(cpu))
break;
@@ -5958,7 +5958,7 @@ select_task_rq_fair(struct task_struct *p, int prev_cpu, int sd_flag, int wake_f
if (sd_flag & SD_BALANCE_WAKE) {
record_wakee(p);
want_affine = !wake_wide(p) && !wake_cap(p, cpu, prev_cpu)
- && cpumask_test_cpu(cpu, tsk_cpus_allowed(p));
+ && cpumask_test_cpu(cpu, &p->cpus_allowed);
}

rcu_read_lock();
@@ -6698,7 +6698,7 @@ int can_migrate_task(struct task_struct *p, struct lb_env *env)
if (throttled_lb_pair(task_group(p), env->src_cpu, env->dst_cpu))
return 0;

- if (!cpumask_test_cpu(env->dst_cpu, tsk_cpus_allowed(p))) {
+ if (!cpumask_test_cpu(env->dst_cpu, &p->cpus_allowed)) {
int cpu;

schedstat_inc(p->se.statistics.nr_failed_migrations_affine);
@@ -6718,7 +6718,7 @@ int can_migrate_task(struct task_struct *p, struct lb_env *env)

/* Prevent to re-select dst_cpu via env's cpus */
for_each_cpu_and(cpu, env->dst_grpmask, env->cpus) {
- if (cpumask_test_cpu(cpu, tsk_cpus_allowed(p))) {
+ if (cpumask_test_cpu(cpu, &p->cpus_allowed)) {
env->flags |= LBF_DST_PINNED;
env->new_dst_cpu = cpu;
break;
@@ -7252,7 +7252,7 @@ check_cpu_capacity(struct rq *rq, struct sched_domain *sd)

/*
* Group imbalance indicates (and tries to solve) the problem where balancing
- * groups is inadequate due to tsk_cpus_allowed() constraints.
+ * groups is inadequate due to ->cpus_allowed constraints.
*
* Imagine a situation of two groups of 4 cpus each and 4 tasks each with a
* cpumask covering 1 cpu of the first group and 3 cpus of the second group.
@@ -8211,8 +8211,7 @@ static int load_balance(int this_cpu, struct rq *this_rq,
* if the curr task on busiest cpu can't be
* moved to this_cpu
*/
- if (!cpumask_test_cpu(this_cpu,
- tsk_cpus_allowed(busiest->curr))) {
+ if (!cpumask_test_cpu(this_cpu, &busiest->curr->cpus_allowed)) {
raw_spin_unlock_irqrestore(&busiest->lock,
flags);
env.flags |= LBF_ALL_PINNED;
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index e8836cfc4cdb..cbd356f63883 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -1591,7 +1591,7 @@ static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
static int pick_rt_task(struct rq *rq, struct task_struct *p, int cpu)
{
if (!task_running(rq, p) &&
- cpumask_test_cpu(cpu, tsk_cpus_allowed(p)))
+ cpumask_test_cpu(cpu, &p->cpus_allowed))
return 1;
return 0;
}
@@ -1726,8 +1726,7 @@ static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq)
* Also make sure that it wasn't scheduled on its rq.
*/
if (unlikely(task_rq(task) != rq ||
- !cpumask_test_cpu(lowest_rq->cpu,
- tsk_cpus_allowed(task)) ||
+ !cpumask_test_cpu(lowest_rq->cpu, &task->cpus_allowed) ||
task_running(rq, task) ||
!rt_task(task) ||
!task_on_rq_queued(task))) {
diff --git a/lib/smp_processor_id.c b/lib/smp_processor_id.c
index 1afec32de6f2..690d75b132fa 100644
--- a/lib/smp_processor_id.c
+++ b/lib/smp_processor_id.c
@@ -22,7 +22,7 @@ notrace static unsigned int check_preemption_disabled(const char *what1,
* Kernel threads bound to a single CPU can safely use
* smp_processor_id():
*/
- if (cpumask_equal(tsk_cpus_allowed(current), cpumask_of(this_cpu)))
+ if (cpumask_equal(&current->cpus_allowed, cpumask_of(this_cpu)))
goto out;

/*
diff --git a/samples/trace_events/trace-events-sample.c b/samples/trace_events/trace-events-sample.c
index 30e282d33d4d..bc7fcf010a5b 100644
--- a/samples/trace_events/trace-events-sample.c
+++ b/samples/trace_events/trace-events-sample.c
@@ -33,7 +33,7 @@ static void simple_thread_func(int cnt)

/* Silly tracepoints */
trace_foo_bar("hello", cnt, array, random_strings[len],
- tsk_cpus_allowed(current));
+ &current->cpus_allowed);

trace_foo_with_template_simple("HELLO", cnt);

--
2.7.4