Merge tag 'sched-psi-2022-10-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull PSI updates from Ingo Molnar:

 - Various performance optimizations, resulting in a 4%-9% speedup in
   the mmtests/config-scheduler-perfpipe micro-benchmark.

 - New interface to turn PSI on/off on a per cgroup level.

* tag 'sched-psi-2022-10-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/psi: Per-cgroup PSI accounting disable/re-enable interface
  sched/psi: Cache parent psi_group to speed up group iteration
  sched/psi: Consolidate cgroup_psi()
  sched/psi: Add PSI_IRQ to track IRQ/SOFTIRQ pressure
  sched/psi: Remove NR_ONCPU task accounting
  sched/psi: Optimize task switch inside shared cgroups again
  sched/psi: Move private helpers to sched/stats.h
  sched/psi: Save percpu memory when !psi_cgroups_enabled
  sched/psi: Don't create cgroup PSI files when psi_disabled
  sched/psi: Fix periodic aggregation shut off
This commit is contained in:
Linus Torvalds
2022-10-14 13:03:00 -07:00
9 changed files with 362 additions and 103 deletions

View File

@@ -3698,27 +3698,27 @@ static int cpu_stat_show(struct seq_file *seq, void *v)
static int cgroup_io_pressure_show(struct seq_file *seq, void *v)
{
struct cgroup *cgrp = seq_css(seq)->cgroup;
struct psi_group *psi = cgroup_ino(cgrp) == 1 ? &psi_system : cgrp->psi;
struct psi_group *psi = cgroup_psi(cgrp);
return psi_show(seq, psi, PSI_IO);
}
static int cgroup_memory_pressure_show(struct seq_file *seq, void *v)
{
struct cgroup *cgrp = seq_css(seq)->cgroup;
struct psi_group *psi = cgroup_ino(cgrp) == 1 ? &psi_system : cgrp->psi;
struct psi_group *psi = cgroup_psi(cgrp);
return psi_show(seq, psi, PSI_MEM);
}
static int cgroup_cpu_pressure_show(struct seq_file *seq, void *v)
{
struct cgroup *cgrp = seq_css(seq)->cgroup;
struct psi_group *psi = cgroup_ino(cgrp) == 1 ? &psi_system : cgrp->psi;
struct psi_group *psi = cgroup_psi(cgrp);
return psi_show(seq, psi, PSI_CPU);
}
static ssize_t cgroup_pressure_write(struct kernfs_open_file *of, char *buf,
size_t nbytes, enum psi_res res)
static ssize_t pressure_write(struct kernfs_open_file *of, char *buf,
size_t nbytes, enum psi_res res)
{
struct cgroup_file_ctx *ctx = of->priv;
struct psi_trigger *new;
@@ -3738,7 +3738,7 @@ static ssize_t cgroup_pressure_write(struct kernfs_open_file *of, char *buf,
return -EBUSY;
}
psi = cgroup_ino(cgrp) == 1 ? &psi_system : cgrp->psi;
psi = cgroup_psi(cgrp);
new = psi_trigger_create(psi, buf, res);
if (IS_ERR(new)) {
cgroup_put(cgrp);
@@ -3755,21 +3755,86 @@ static ssize_t cgroup_io_pressure_write(struct kernfs_open_file *of,
char *buf, size_t nbytes,
loff_t off)
{
return cgroup_pressure_write(of, buf, nbytes, PSI_IO);
return pressure_write(of, buf, nbytes, PSI_IO);
}
static ssize_t cgroup_memory_pressure_write(struct kernfs_open_file *of,
char *buf, size_t nbytes,
loff_t off)
{
return cgroup_pressure_write(of, buf, nbytes, PSI_MEM);
return pressure_write(of, buf, nbytes, PSI_MEM);
}
static ssize_t cgroup_cpu_pressure_write(struct kernfs_open_file *of,
char *buf, size_t nbytes,
loff_t off)
{
return cgroup_pressure_write(of, buf, nbytes, PSI_CPU);
return pressure_write(of, buf, nbytes, PSI_CPU);
}
#ifdef CONFIG_IRQ_TIME_ACCOUNTING
static int cgroup_irq_pressure_show(struct seq_file *seq, void *v)
{
struct cgroup *cgrp = seq_css(seq)->cgroup;
struct psi_group *psi = cgroup_psi(cgrp);
return psi_show(seq, psi, PSI_IRQ);
}
static ssize_t cgroup_irq_pressure_write(struct kernfs_open_file *of,
char *buf, size_t nbytes,
loff_t off)
{
return pressure_write(of, buf, nbytes, PSI_IRQ);
}
#endif
static int cgroup_pressure_show(struct seq_file *seq, void *v)
{
struct cgroup *cgrp = seq_css(seq)->cgroup;
struct psi_group *psi = cgroup_psi(cgrp);
seq_printf(seq, "%d\n", psi->enabled);
return 0;
}
static ssize_t cgroup_pressure_write(struct kernfs_open_file *of,
char *buf, size_t nbytes,
loff_t off)
{
ssize_t ret;
int enable;
struct cgroup *cgrp;
struct psi_group *psi;
ret = kstrtoint(strstrip(buf), 0, &enable);
if (ret)
return ret;
if (enable < 0 || enable > 1)
return -ERANGE;
cgrp = cgroup_kn_lock_live(of->kn, false);
if (!cgrp)
return -ENOENT;
psi = cgroup_psi(cgrp);
if (psi->enabled != enable) {
int i;
/* show or hide {cpu,memory,io,irq}.pressure files */
for (i = 0; i < NR_PSI_RESOURCES; i++)
cgroup_file_show(&cgrp->psi_files[i], enable);
psi->enabled = enable;
if (enable)
psi_cgroup_restart(psi);
}
cgroup_kn_unlock(of->kn);
return nbytes;
}
static __poll_t cgroup_pressure_poll(struct kernfs_open_file *of,
@@ -3789,6 +3854,9 @@ static void cgroup_pressure_release(struct kernfs_open_file *of)
bool cgroup_psi_enabled(void)
{
if (static_branch_likely(&psi_disabled))
return false;
return (cgroup_feature_disable_mask & (1 << OPT_FEATURE_PRESSURE)) == 0;
}
@@ -5175,6 +5243,7 @@ static struct cftype cgroup_psi_files[] = {
#ifdef CONFIG_PSI
{
.name = "io.pressure",
.file_offset = offsetof(struct cgroup, psi_files[PSI_IO]),
.seq_show = cgroup_io_pressure_show,
.write = cgroup_io_pressure_write,
.poll = cgroup_pressure_poll,
@@ -5182,6 +5251,7 @@ static struct cftype cgroup_psi_files[] = {
},
{
.name = "memory.pressure",
.file_offset = offsetof(struct cgroup, psi_files[PSI_MEM]),
.seq_show = cgroup_memory_pressure_show,
.write = cgroup_memory_pressure_write,
.poll = cgroup_pressure_poll,
@@ -5189,11 +5259,27 @@ static struct cftype cgroup_psi_files[] = {
},
{
.name = "cpu.pressure",
.file_offset = offsetof(struct cgroup, psi_files[PSI_CPU]),
.seq_show = cgroup_cpu_pressure_show,
.write = cgroup_cpu_pressure_write,
.poll = cgroup_pressure_poll,
.release = cgroup_pressure_release,
},
#ifdef CONFIG_IRQ_TIME_ACCOUNTING
{
.name = "irq.pressure",
.file_offset = offsetof(struct cgroup, psi_files[PSI_IRQ]),
.seq_show = cgroup_irq_pressure_show,
.write = cgroup_irq_pressure_write,
.poll = cgroup_pressure_poll,
.release = cgroup_pressure_release,
},
#endif
{
.name = "cgroup.pressure",
.seq_show = cgroup_pressure_show,
.write = cgroup_pressure_write,
},
#endif /* CONFIG_PSI */
{ } /* terminate */
};