[Devel] [PATCH VZ10 v6 7/9] ve: Introduce per-VE failcount
Vasileios Almpanis
vasileios.almpanis at virtuozzo.com
Wed Aug 19 16:16:17 MSK 2026
> It may be useful to have a history of resource limit hits for every VE,
> this may simplify debugging and provide some information about the
> resources usage.
>
> This information is provided by ve.failcount file, any write to it
> resets all failcounts.
>
> To add a new failcounter we need to create a new atomic_t field
> name_failcount in ve structure and add a new VE_FC_ENTRY in
> ve_failcounts array.
>
> One change, unrelated to failcounts: aio fields are now initialized
> in ve0.
>
> https://virtuozzo.atlassian.net/browse/VSTOR-135520
>
> Feature: per-ve failcounters
> Signed-off-by: Vladimir Riabchun <vladimir.riabchun at virtuozzo.com>
>
> diff --git a/fs/aio.c b/fs/aio.c
> index cb63416af135..3fa07cc626f8 100644
> --- a/fs/aio.c
> +++ b/fs/aio.c
> @@ -814,6 +814,7 @@ static struct kioctx *ioctx_alloc(unsigned nr_events)
> spin_lock(&ve->aio_nr_lock);
> if (ve->aio_nr + ctx->max_reqs > ve->aio_max_nr ||
> ve->aio_nr + ctx->max_reqs < ve->aio_nr) {
> + atomic_inc(&ve->aio_failcount);
> spin_unlock(&ve->aio_nr_lock);
> err = -EAGAIN;
> goto err_ctx;
> diff --git a/fs/namespace.c b/fs/namespace.c
> index c9e2ab9b3b57..eeeb2f780e46 100644
> --- a/fs/namespace.c
> +++ b/fs/namespace.c
> @@ -3369,6 +3369,8 @@ static inline int ve_try_reserve_mount(struct ve_struct *ve)
>
> if (ret)
> get_ve(ve);
> + else
> + atomic_inc(&ve->mnt_failcount);
> return ret;
> }
>
> diff --git a/include/linux/ve.h b/include/linux/ve.h
> index 5687faad46ff..9e73527e970e 100644
> --- a/include/linux/ve.h
> +++ b/include/linux/ve.h
> @@ -72,12 +72,15 @@ struct ve_struct {
> struct kmapset_key proc_perms_key;
>
> atomic_t netns_avail_nr;
> + atomic_t netns_failcount;
> int netns_max_nr;
>
> atomic_t netif_avail_nr;
> + atomic_t netif_failcount;
> int netif_max_nr;
>
> atomic_t bpf_prog_avail_nr;
> + atomic_t bpf_prog_failcount;
> int bpf_prog_max_nr;
>
> atomic64_t _uevent_seqnum;
> @@ -86,6 +89,7 @@ struct ve_struct {
>
> atomic_t arp_neigh_nr;
> atomic_t nd_neigh_nr;
> + atomic_t neigh_tbl_failcount;
> unsigned long meminfo_val;
>
> /*
> @@ -94,6 +98,7 @@ struct ve_struct {
> * other containers.
> */
> atomic_t mnt_avail_nr; /* number of available VE mounts */
> + atomic_t mnt_failcount;
> int mnt_max_nr;
>
> #ifdef CONFIG_COREDUMP
> @@ -121,6 +126,7 @@ struct ve_struct {
> spinlock_t aio_nr_lock;
> unsigned long aio_nr;
> unsigned long aio_max_nr;
> + atomic_t aio_failcount;
> #endif
> struct vfsmount *devtmpfs_mnt;
> };
> diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
> index c94d4240e3d3..9d57e7999ae0 100644
> --- a/kernel/bpf/syscall.c
> +++ b/kernel/bpf/syscall.c
> @@ -2891,6 +2891,7 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size)
> if (!bpf_cap && type == BPF_PROG_TYPE_CGROUP_DEVICE) {
> load_ve = get_exec_env();
> if (atomic_dec_if_positive(&load_ve->bpf_prog_avail_nr) < 0) {
> + atomic_inc(&load_ve->bpf_prog_failcount);
> load_ve = NULL;
> err = -ENOSPC;
> goto put_token;
> diff --git a/kernel/ve/ve.c b/kernel/ve/ve.c
> index 0f02835765ff..55a83b0b5981 100644
> --- a/kernel/ve/ve.c
> +++ b/kernel/ve/ve.c
> @@ -99,10 +99,13 @@ struct ve_struct ve0 = {
> .features = -1,
> .sched_lat_ve.cur = &ve0_lat_stats,
> .netns_avail_nr = ATOMIC_INIT(INT_MAX),
> + .netns_failcount = ATOMIC_INIT(0),
> .netns_max_nr = INT_MAX,
> .netif_avail_nr = ATOMIC_INIT(INT_MAX),
> + .netif_failcount = ATOMIC_INIT(0),
> .netif_max_nr = INT_MAX,
> .bpf_prog_avail_nr = ATOMIC_INIT(INT_MAX),
> + .bpf_prog_failcount = ATOMIC_INIT(0),
> .bpf_prog_max_nr = INT_MAX,
> .fsync_enable = FSYNC_FILTERED,
> ._randomize_va_space =
> @@ -114,8 +117,16 @@ struct ve_struct ve0 = {
>
> .arp_neigh_nr = ATOMIC_INIT(0),
> .nd_neigh_nr = ATOMIC_INIT(0),
> + .neigh_tbl_failcount = ATOMIC_INIT(0),
> .mnt_avail_nr = ATOMIC_INIT(INT_MAX),
> .mnt_max_nr = INT_MAX,
> + .mnt_failcount = ATOMIC_INIT(0),
> +#ifdef CONFIG_AIO
> + .aio_nr_lock = __SPIN_LOCK_UNLOCKED(aio_nr_lock),
> + .aio_nr = 0,
> + .aio_max_nr = AIO_MAX_NR_DEFAULT,
> + .aio_failcount = ATOMIC_INIT(0),
> +#endif
> .meminfo_val = VE_MEMINFO_SYSTEM,
> .umh_running_helpers = ATOMIC_INIT(0),
> .umh_helpers_waitq = __WAIT_QUEUE_HEAD_INITIALIZER(ve0.umh_helpers_waitq),
> @@ -780,12 +791,15 @@ static struct cgroup_subsys_state *ve_create(struct cgroup_subsys_state *parent_
> ve->fsync_enable = FSYNC_FILTERED;
>
> atomic_set(&ve->netns_avail_nr, NETNS_MAX_NR_DEFAULT);
> + atomic_set(&ve->netns_failcount, 0);
> ve->netns_max_nr = NETNS_MAX_NR_DEFAULT;
>
> atomic_set(&ve->netif_avail_nr, NETIF_MAX_NR_DEFAULT);
> + atomic_set(&ve->netif_failcount, 0);
> ve->netif_max_nr = NETIF_MAX_NR_DEFAULT;
>
> atomic_set(&ve->bpf_prog_avail_nr, BPF_PROG_MAX_NR_DEFAULT);
> + atomic_set(&ve->bpf_prog_failcount, 0);
> ve->bpf_prog_max_nr = BPF_PROG_MAX_NR_DEFAULT;
>
> err = ve_log_init(ve);
> @@ -812,7 +826,9 @@ static struct cgroup_subsys_state *ve_create(struct cgroup_subsys_state *parent_
>
> atomic_set(&ve->arp_neigh_nr, 0);
> atomic_set(&ve->nd_neigh_nr, 0);
> + atomic_set(&ve->neigh_tbl_failcount, 0);
> ve->mnt_max_nr = MNT_MAX_NR_DEFAULT;
> + atomic_set(&ve->mnt_failcount, 0);
> atomic_set(&ve->mnt_avail_nr, MNT_MAX_NR_DEFAULT);
>
> #ifdef CONFIG_COREDUMP
> @@ -825,6 +841,7 @@ static struct cgroup_subsys_state *ve_create(struct cgroup_subsys_state *parent_
> spin_lock_init(&ve->aio_nr_lock);
> ve->aio_nr = 0;
> ve->aio_max_nr = AIO_MAX_NR_DEFAULT;
> + atomic_set(&ve->aio_failcount, 0);
> #endif
>
> return &ve->css;
> @@ -1065,6 +1082,50 @@ VE_RESOURCE(mnt);
> VE_RESOURCE(netif);
> VE_RESOURCE(bpf_prog);
>
> +static const struct ve_failcount_entry {
> + const char *name;
> + size_t offset;
> +} ve_failcounts[] = {
> +#define VE_FC_ENTRY(name) { #name, offsetof(struct ve_struct, name##_failcount) }
> + VE_FC_ENTRY(netns),
> + VE_FC_ENTRY(mnt),
> + VE_FC_ENTRY(netif),
> + VE_FC_ENTRY(bpf_prog),
> + VE_FC_ENTRY(neigh_tbl),
> +#ifdef CONFIG_AIO
> + VE_FC_ENTRY(aio),
> +#endif
> + {}
> +};
> +
> +static int ve_failcount_read(struct seq_file *sf, void *v)
> +{
> + struct ve_struct *ve = css_to_ve(seq_css(sf));
> + const struct ve_failcount_entry *entry;
> + atomic_t *fc;
> +
> + for (entry = ve_failcounts; entry->name; entry++) {
> + fc = (void *)ve + entry->offset;
> + seq_printf(sf, "%s: %d\n", entry->name, atomic_read(fc));
> + }
> + return 0;
> +}
> +
> +static ssize_t ve_failcount_write(struct kernfs_open_file *of, char *buf,
> + size_t nbytes, loff_t off)
> +{
> + struct ve_struct *ve = css_to_ve(of_css(of));
> + const struct ve_failcount_entry *entry;
> + atomic_t *fc;
Should we allow the container itself to reset the failcount? All other
resource write handlers have a check that return EPERM when we are not
super ve. Here we will allow the container to reset its failcount so it
will no longer be trustworthy information.
--
Vasileios Almpanis <vasileios.almpanis at virtuozzo.com>
More information about the Devel
mailing list