Commit 7a1bac1d authored by Chen Wandun's avatar Chen Wandun Committed by Lu Jialin
Browse files

psi: dont alloc memory for psi by default 

mainline inclusion
from mainline-v6.0-rc1
commit 5f69a657
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8BCV4

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=5f69a6577bc33d8f6d6bbe02bccdeb357b287f56



--------------------------------

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: default avatarChen Wandun <chenwandun@huawei.com>
Acked-by: default avatarJohannes Weiner <hannes@cmpxchg.org>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Conflict:
	include/linux/cgroup-defs.h
	include/linux/cgroup.h
	kernel/cgroup/cgroup.c
Signed-off-by: default avatarLu Jialin <lujialin4@huawei.com>
parent 09a65211

include/linux/cgroup-defs.h

+3 −3
Original line number Diff line number Diff line
@@ -492,9 +492,9 @@ struct cgroup { 
	/*

	 * It is accessed only the cgroup core code and so changes made to

	 * the cgroup structure should not affect third-party kernel modules.

	 * The member is unused now.

	 */

	struct psi_group psi;



	KABI_DEPRECATE(struct psi_group, psi)

	/* used to store eBPF programs */

	struct cgroup_bpf bpf;
@@ -504,7 +504,7 @@ struct cgroup { 
	/* Used to store internal freezer state */

	struct cgroup_freezer_state freezer;



	KABI_RESERVE(1)

	KABI_USE(1, struct psi_group *psi)

	KABI_RESERVE(2)

	KABI_RESERVE(3)

include/linux/cgroup.h

+1 −1
Original line number Diff line number Diff line
@@ -675,7 +675,7 @@ 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;

}



static inline void cgroup_init_kthreadd(void)

kernel/cgroup/cgroup.c

+5 −5
Original line number Diff line number Diff line
@@ -3677,21 +3677,21 @@ 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);

}
@@ -3717,7 +3717,7 @@ 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, of);

	if (IS_ERR(new)) {

		cgroup_put(cgrp);
@@ -3755,7 +3755,7 @@ static ssize_t cgroup_cpu_pressure_write(struct kernfs_open_file *of, 
static int cgroup_irq_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_IRQ);

}

kernel/sched/psi.c

+13 −6
Original line number Diff line number Diff line
@@ -1034,10 +1034,16 @@ 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;

}
@@ -1046,10 +1052,11 @@ 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);

}



/**