psi: dont alloc memory for psi by default

Memory about struct psi_group is allocated by default for
each cgroup even if psi_disabled is true, in this case, these
allocated memory is waste, so alloc memory for struct psi_group
only when psi_disabled is false.

Signed-off-by: Chen Wandun <chenwandun@huawei.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Chen Wandun 2022-05-26 20:26:56 +08:00 committed by Tejun Heo
parent e71e60cd74
commit 5f69a6577b
4 changed files with 19 additions and 12 deletions

View File

@ -475,7 +475,7 @@ struct cgroup {
struct work_struct release_agent_work;
/* used to track pressure stalls */
struct psi_group psi;
struct psi_group *psi;
/* used to store eBPF programs */
struct cgroup_bpf bpf;

View File

@ -674,7 +674,7 @@ static inline void pr_cont_cgroup_path(struct cgroup *cgrp)
static inline struct psi_group *cgroup_psi(struct cgroup *cgrp)
{
return &cgrp->psi;
return cgrp->psi;
}
bool cgroup_psi_enabled(void);

View File

@ -3609,21 +3609,21 @@ 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_ino(cgrp) == 1 ? &psi_system : cgrp->psi;
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_ino(cgrp) == 1 ? &psi_system : cgrp->psi;
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_ino(cgrp) == 1 ? &psi_system : cgrp->psi;
return psi_show(seq, psi, PSI_CPU);
}
@ -3649,7 +3649,7 @@ 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_ino(cgrp) == 1 ? &psi_system : cgrp->psi;
new = psi_trigger_create(psi, buf, nbytes, res);
if (IS_ERR(new)) {
cgroup_put(cgrp);

View File

@ -957,10 +957,16 @@ int psi_cgroup_alloc(struct cgroup *cgroup)
if (static_branch_likely(&psi_disabled))
return 0;
cgroup->psi.pcpu = alloc_percpu(struct psi_group_cpu);
if (!cgroup->psi.pcpu)
cgroup->psi = kmalloc(sizeof(struct psi_group), GFP_KERNEL);
if (!cgroup->psi)
return -ENOMEM;
group_init(&cgroup->psi);
cgroup->psi->pcpu = alloc_percpu(struct psi_group_cpu);
if (!cgroup->psi->pcpu) {
kfree(cgroup->psi);
return -ENOMEM;
}
group_init(cgroup->psi);
return 0;
}
@ -969,10 +975,11 @@ void psi_cgroup_free(struct cgroup *cgroup)
if (static_branch_likely(&psi_disabled))
return;
cancel_delayed_work_sync(&cgroup->psi.avgs_work);
free_percpu(cgroup->psi.pcpu);
cancel_delayed_work_sync(&cgroup->psi->avgs_work);
free_percpu(cgroup->psi->pcpu);
/* All triggers must be removed by now */
WARN_ONCE(cgroup->psi.poll_states, "psi: trigger leak\n");
WARN_ONCE(cgroup->psi->poll_states, "psi: trigger leak\n");
kfree(cgroup->psi);
}
/**