diff options
| author | Breno Leitao <leitao@debian.org> | 2026-08-05 07:52:36 -0700 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2026-08-10 11:47:20 -1000 |
| commit | a5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656 (patch) | |
| tree | 39f5b258386e1127d253d293194e9a2991bf3c34 /drivers/hv/mshv_debugfs.c | |
| download | linux-stable-a5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656.tar.gz linux-stable-a5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656.zip | |
workqueue: skip the node_nr_active update for non-unbound workqueuesgrafted
apply_wqattrs_commit() updates node_nr_active->max unconditionally.
wq->node_nr_active[] is only allocated for unbound workqueues, so guard
the call before per-cpu workqueues start using this path.
No functional change: only unbound workqueues reach apply_wqattrs_*()
today.
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'drivers/hv/mshv_debugfs.c')
| -rw-r--r-- | drivers/hv/mshv_debugfs.c | 729 |
1 files changed, 729 insertions, 0 deletions
diff --git a/drivers/hv/mshv_debugfs.c b/drivers/hv/mshv_debugfs.c new file mode 100644 index 000000000..3c3e02237 --- /dev/null +++ b/drivers/hv/mshv_debugfs.c @@ -0,0 +1,729 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2026, Microsoft Corporation. + * + * The /sys/kernel/debug/mshv directory contents. + * Contains various statistics data, provided by the hypervisor. + * + * Authors: Microsoft Linux virtualization team + */ + +#include <linux/debugfs.h> +#include <linux/stringify.h> +#include <asm/mshyperv.h> +#include <linux/slab.h> + +#include "mshv.h" +#include "mshv_root.h" + +/* Ensure this file is not used elsewhere by accident */ +#define MSHV_DEBUGFS_C +#include "mshv_debugfs_counters.c" + +#define U32_BUF_SZ 11 +#define U64_BUF_SZ 21 +/* Only support SELF and PARENT areas */ +#define NUM_STATS_AREAS 2 +static_assert(HV_STATS_AREA_SELF == 0 && HV_STATS_AREA_PARENT == 1, + "SELF and PARENT areas must be usable as indices into an array of size NUM_STATS_AREAS"); +/* HV_HYPERVISOR_COUNTER */ +#define HV_HYPERVISOR_COUNTER_LOGICAL_PROCESSORS 1 + +static struct dentry *mshv_debugfs; +static struct dentry *mshv_debugfs_partition; +static struct dentry *mshv_debugfs_lp; +static struct dentry **parent_vp_stats; +static struct dentry *parent_partition_stats; + +static u64 mshv_lps_count; +static struct hv_stats_page **mshv_lps_stats; + +static int lp_stats_show(struct seq_file *m, void *v) +{ + const struct hv_stats_page *stats = m->private; + int idx; + + for (idx = 0; idx < ARRAY_SIZE(hv_lp_counters); idx++) { + char *name = hv_lp_counters[idx]; + + if (!name) + continue; + seq_printf(m, "%-32s: %llu\n", name, stats->data[idx]); + } + + return 0; +} +DEFINE_SHOW_ATTRIBUTE(lp_stats); + +static void mshv_lp_stats_unmap(u32 lp_index) +{ + union hv_stats_object_identity identity = { + .lp.lp_index = lp_index, + .lp.stats_area_type = HV_STATS_AREA_SELF, + }; + int err; + + err = hv_unmap_stats_page(HV_STATS_OBJECT_LOGICAL_PROCESSOR, + mshv_lps_stats[lp_index], &identity); + if (err) + pr_err("%s: failed to unmap logical processor %u stats, err: %d\n", + __func__, lp_index, err); + + mshv_lps_stats[lp_index] = NULL; +} + +static struct hv_stats_page * __init mshv_lp_stats_map(u32 lp_index) +{ + union hv_stats_object_identity identity = { + .lp.lp_index = lp_index, + .lp.stats_area_type = HV_STATS_AREA_SELF, + }; + struct hv_stats_page *stats; + int err; + + err = hv_map_stats_page(HV_STATS_OBJECT_LOGICAL_PROCESSOR, &identity, + &stats); + if (err) { + pr_err("%s: failed to map logical processor %u stats, err: %d\n", + __func__, lp_index, err); + return ERR_PTR(err); + } + mshv_lps_stats[lp_index] = stats; + + return stats; +} + +static struct hv_stats_page * __init lp_debugfs_stats_create(u32 lp_index, + struct dentry *parent) +{ + struct dentry *dentry; + struct hv_stats_page *stats; + + stats = mshv_lp_stats_map(lp_index); + if (IS_ERR(stats)) + return stats; + + dentry = debugfs_create_file("stats", 0400, parent, + stats, &lp_stats_fops); + if (IS_ERR(dentry)) { + mshv_lp_stats_unmap(lp_index); + return ERR_CAST(dentry); + } + return stats; +} + +static int __init lp_debugfs_create(u32 lp_index, struct dentry *parent) +{ + struct dentry *idx; + char lp_idx_str[U32_BUF_SZ]; + struct hv_stats_page *stats; + int err; + + sprintf(lp_idx_str, "%u", lp_index); + + idx = debugfs_create_dir(lp_idx_str, parent); + if (IS_ERR(idx)) + return PTR_ERR(idx); + + stats = lp_debugfs_stats_create(lp_index, idx); + if (IS_ERR(stats)) { + err = PTR_ERR(stats); + goto remove_debugfs_lp_idx; + } + + return 0; + +remove_debugfs_lp_idx: + debugfs_remove_recursive(idx); + return err; +} + +static void mshv_debugfs_lp_remove(void) +{ + int lp_index; + + debugfs_remove_recursive(mshv_debugfs_lp); + + for (lp_index = 0; lp_index < mshv_lps_count; lp_index++) + mshv_lp_stats_unmap(lp_index); + + kfree(mshv_lps_stats); + mshv_lps_stats = NULL; +} + +static int __init mshv_debugfs_lp_create(struct dentry *parent) +{ + struct dentry *lp_dir; + int err, lp_index; + + mshv_lps_stats = kzalloc_objs(*mshv_lps_stats, mshv_lps_count, + GFP_KERNEL_ACCOUNT); + + if (!mshv_lps_stats) + return -ENOMEM; + + lp_dir = debugfs_create_dir("lp", parent); + if (IS_ERR(lp_dir)) { + err = PTR_ERR(lp_dir); + goto free_lp_stats; + } + + for (lp_index = 0; lp_index < mshv_lps_count; lp_index++) { + err = lp_debugfs_create(lp_index, lp_dir); + if (err) + goto remove_debugfs_lps; + } + + mshv_debugfs_lp = lp_dir; + + return 0; + +remove_debugfs_lps: + for (lp_index -= 1; lp_index >= 0; lp_index--) + mshv_lp_stats_unmap(lp_index); + debugfs_remove_recursive(lp_dir); +free_lp_stats: + kfree(mshv_lps_stats); + mshv_lps_stats = NULL; + + return err; +} + +static int vp_stats_show(struct seq_file *m, void *v) +{ + const struct hv_stats_page **pstats = m->private; + u64 parent_val, self_val; + int idx; + + /* + * For VP and partition stats, there may be two stats areas mapped, + * SELF and PARENT. These refer to the privilege level of the data in + * each page. Some fields may be 0 in SELF and nonzero in PARENT, or + * vice versa. + * + * Hence, prioritize printing from the PARENT page (more privileged + * data), but use the value from the SELF page if the PARENT value is + * 0. + */ + + for (idx = 0; idx < ARRAY_SIZE(hv_vp_counters); idx++) { + char *name = hv_vp_counters[idx]; + + if (!name) + continue; + + parent_val = pstats[HV_STATS_AREA_PARENT]->data[idx]; + self_val = pstats[HV_STATS_AREA_SELF]->data[idx]; + seq_printf(m, "%-43s: %llu\n", name, + parent_val ? parent_val : self_val); + } + + return 0; +} +DEFINE_SHOW_ATTRIBUTE(vp_stats); + +static void vp_debugfs_remove(struct dentry *vp_stats) +{ + debugfs_remove_recursive(vp_stats->d_parent); +} + +static int vp_debugfs_create(u64 partition_id, u32 vp_index, + struct hv_stats_page **pstats, + struct dentry **vp_stats_ptr, + struct dentry *parent) +{ + struct dentry *vp_idx_dir, *d; + char vp_idx_str[U32_BUF_SZ]; + int err; + + sprintf(vp_idx_str, "%u", vp_index); + + vp_idx_dir = debugfs_create_dir(vp_idx_str, parent); + if (IS_ERR(vp_idx_dir)) + return PTR_ERR(vp_idx_dir); + + d = debugfs_create_file("stats", 0400, vp_idx_dir, + pstats, &vp_stats_fops); + if (IS_ERR(d)) { + err = PTR_ERR(d); + goto remove_debugfs_vp_idx; + } + + *vp_stats_ptr = d; + + return 0; + +remove_debugfs_vp_idx: + debugfs_remove_recursive(vp_idx_dir); + return err; +} + +static int partition_stats_show(struct seq_file *m, void *v) +{ + const struct hv_stats_page **pstats = m->private; + u64 parent_val, self_val; + int idx; + + for (idx = 0; idx < ARRAY_SIZE(hv_partition_counters); idx++) { + char *name = hv_partition_counters[idx]; + + if (!name) + continue; + + parent_val = pstats[HV_STATS_AREA_PARENT]->data[idx]; + self_val = pstats[HV_STATS_AREA_SELF]->data[idx]; + seq_printf(m, "%-37s: %llu\n", name, + parent_val ? parent_val : self_val); + } + + return 0; +} +DEFINE_SHOW_ATTRIBUTE(partition_stats); + +static void mshv_partition_stats_unmap(u64 partition_id, + struct hv_stats_page *stats_page, + enum hv_stats_area_type stats_area_type) +{ + union hv_stats_object_identity identity = { + .partition.partition_id = partition_id, + .partition.stats_area_type = stats_area_type, + }; + int err; + + err = hv_unmap_stats_page(HV_STATS_OBJECT_PARTITION, stats_page, + &identity); + if (err) + pr_err("%s: failed to unmap partition %lld %s stats, err: %d\n", + __func__, partition_id, + (stats_area_type == HV_STATS_AREA_SELF) ? "self" : "parent", + err); +} + +static struct hv_stats_page *mshv_partition_stats_map(u64 partition_id, + enum hv_stats_area_type stats_area_type) +{ + union hv_stats_object_identity identity = { + .partition.partition_id = partition_id, + .partition.stats_area_type = stats_area_type, + }; + struct hv_stats_page *stats; + int err; + + err = hv_map_stats_page(HV_STATS_OBJECT_PARTITION, &identity, &stats); + if (err) { + pr_err("%s: failed to map partition %lld %s stats, err: %d\n", + __func__, partition_id, + (stats_area_type == HV_STATS_AREA_SELF) ? "self" : "parent", + err); + return ERR_PTR(err); + } + return stats; +} + +static int mshv_debugfs_partition_stats_create(u64 partition_id, + struct dentry **partition_stats_ptr, + struct dentry *parent) +{ + struct dentry *dentry; + struct hv_stats_page **pstats; + int err; + + pstats = kzalloc_objs(struct hv_stats_page *, NUM_STATS_AREAS, + GFP_KERNEL_ACCOUNT); + if (!pstats) + return -ENOMEM; + + pstats[HV_STATS_AREA_SELF] = mshv_partition_stats_map(partition_id, + HV_STATS_AREA_SELF); + if (IS_ERR(pstats[HV_STATS_AREA_SELF])) { + err = PTR_ERR(pstats[HV_STATS_AREA_SELF]); + goto cleanup; + } + + /* + * L1VH partition cannot access its partition stats in parent area. + */ + if (is_l1vh_parent(partition_id)) { + pstats[HV_STATS_AREA_PARENT] = pstats[HV_STATS_AREA_SELF]; + } else { + pstats[HV_STATS_AREA_PARENT] = mshv_partition_stats_map(partition_id, + HV_STATS_AREA_PARENT); + if (IS_ERR(pstats[HV_STATS_AREA_PARENT])) { + err = PTR_ERR(pstats[HV_STATS_AREA_PARENT]); + goto unmap_self; + } + if (!pstats[HV_STATS_AREA_PARENT]) + pstats[HV_STATS_AREA_PARENT] = pstats[HV_STATS_AREA_SELF]; + } + + dentry = debugfs_create_file("stats", 0400, parent, + pstats, &partition_stats_fops); + if (IS_ERR(dentry)) { + err = PTR_ERR(dentry); + goto unmap_partition_stats; + } + + *partition_stats_ptr = dentry; + return 0; + +unmap_partition_stats: + if (pstats[HV_STATS_AREA_PARENT] != pstats[HV_STATS_AREA_SELF]) + mshv_partition_stats_unmap(partition_id, pstats[HV_STATS_AREA_PARENT], + HV_STATS_AREA_PARENT); +unmap_self: + mshv_partition_stats_unmap(partition_id, pstats[HV_STATS_AREA_SELF], + HV_STATS_AREA_SELF); +cleanup: + kfree(pstats); + return err; +} + +static void partition_debugfs_remove(u64 partition_id, struct dentry *dentry) +{ + struct hv_stats_page **pstats = NULL; + + pstats = dentry->d_inode->i_private; + + debugfs_remove_recursive(dentry->d_parent); + + if (pstats[HV_STATS_AREA_PARENT] != pstats[HV_STATS_AREA_SELF]) { + mshv_partition_stats_unmap(partition_id, + pstats[HV_STATS_AREA_PARENT], + HV_STATS_AREA_PARENT); + } + + mshv_partition_stats_unmap(partition_id, + pstats[HV_STATS_AREA_SELF], + HV_STATS_AREA_SELF); + + kfree(pstats); +} + +static int partition_debugfs_create(u64 partition_id, + struct dentry **vp_dir_ptr, + struct dentry **partition_stats_ptr, + struct dentry *parent) +{ + char part_id_str[U64_BUF_SZ]; + struct dentry *part_id_dir, *vp_dir; + int err; + + if (is_l1vh_parent(partition_id)) + sprintf(part_id_str, "self"); + else + sprintf(part_id_str, "%llu", partition_id); + + part_id_dir = debugfs_create_dir(part_id_str, parent); + if (IS_ERR(part_id_dir)) + return PTR_ERR(part_id_dir); + + vp_dir = debugfs_create_dir("vp", part_id_dir); + if (IS_ERR(vp_dir)) { + err = PTR_ERR(vp_dir); + goto remove_debugfs_partition_id; + } + + err = mshv_debugfs_partition_stats_create(partition_id, + partition_stats_ptr, + part_id_dir); + if (err) + goto remove_debugfs_partition_id; + + *vp_dir_ptr = vp_dir; + + return 0; + +remove_debugfs_partition_id: + debugfs_remove_recursive(part_id_dir); + return err; +} + +static void parent_vp_debugfs_remove(u32 vp_index, + struct dentry *vp_stats_ptr) +{ + struct hv_stats_page **pstats; + + pstats = vp_stats_ptr->d_inode->i_private; + vp_debugfs_remove(vp_stats_ptr); + mshv_vp_stats_unmap(hv_current_partition_id, vp_index, pstats); + kfree(pstats); +} + +static void mshv_debugfs_parent_partition_remove(void) +{ + int idx; + + for_each_online_cpu(idx) + parent_vp_debugfs_remove(hv_vp_index[idx], + parent_vp_stats[idx]); + + partition_debugfs_remove(hv_current_partition_id, + parent_partition_stats); + kfree(parent_vp_stats); + parent_vp_stats = NULL; + parent_partition_stats = NULL; +} + +static int __init parent_vp_debugfs_create(u32 vp_index, + struct dentry **vp_stats_ptr, + struct dentry *parent) +{ + struct hv_stats_page **pstats; + int err; + + pstats = kzalloc_objs(struct hv_stats_page *, NUM_STATS_AREAS, + GFP_KERNEL_ACCOUNT); + if (!pstats) + return -ENOMEM; + + err = mshv_vp_stats_map(hv_current_partition_id, vp_index, pstats); + if (err) + goto cleanup; + + err = vp_debugfs_create(hv_current_partition_id, vp_index, pstats, + vp_stats_ptr, parent); + if (err) + goto unmap_vp_stats; + + return 0; + +unmap_vp_stats: + mshv_vp_stats_unmap(hv_current_partition_id, vp_index, pstats); +cleanup: + kfree(pstats); + return err; +} + +static int __init mshv_debugfs_parent_partition_create(void) +{ + struct dentry *vp_dir; + int err, idx, i; + + mshv_debugfs_partition = debugfs_create_dir("partition", + mshv_debugfs); + if (IS_ERR(mshv_debugfs_partition)) + return PTR_ERR(mshv_debugfs_partition); + + err = partition_debugfs_create(hv_current_partition_id, + &vp_dir, + &parent_partition_stats, + mshv_debugfs_partition); + if (err) + goto remove_debugfs_partition; + + parent_vp_stats = kzalloc_objs(*parent_vp_stats, nr_cpu_ids); + if (!parent_vp_stats) { + err = -ENOMEM; + goto remove_debugfs_partition; + } + + for_each_online_cpu(idx) { + err = parent_vp_debugfs_create(hv_vp_index[idx], + &parent_vp_stats[idx], + vp_dir); + if (err) + goto remove_debugfs_partition_vp; + } + + return 0; + +remove_debugfs_partition_vp: + for_each_online_cpu(i) { + if (i >= idx) + break; + parent_vp_debugfs_remove(i, parent_vp_stats[i]); + } + partition_debugfs_remove(hv_current_partition_id, + parent_partition_stats); + + kfree(parent_vp_stats); + parent_vp_stats = NULL; + parent_partition_stats = NULL; + +remove_debugfs_partition: + debugfs_remove_recursive(mshv_debugfs_partition); + mshv_debugfs_partition = NULL; + return err; +} + +static int hv_stats_show(struct seq_file *m, void *v) +{ + const struct hv_stats_page *stats = m->private; + int idx; + + for (idx = 0; idx < ARRAY_SIZE(hv_hypervisor_counters); idx++) { + char *name = hv_hypervisor_counters[idx]; + + if (!name) + continue; + seq_printf(m, "%-27s: %llu\n", name, stats->data[idx]); + } + + return 0; +} +DEFINE_SHOW_ATTRIBUTE(hv_stats); + +static void mshv_hv_stats_unmap(void) +{ + union hv_stats_object_identity identity = { + .hv.stats_area_type = HV_STATS_AREA_SELF, + }; + int err; + + err = hv_unmap_stats_page(HV_STATS_OBJECT_HYPERVISOR, NULL, &identity); + if (err) + pr_err("%s: failed to unmap hypervisor stats: %d\n", + __func__, err); +} + +static void * __init mshv_hv_stats_map(void) +{ + union hv_stats_object_identity identity = { + .hv.stats_area_type = HV_STATS_AREA_SELF, + }; + struct hv_stats_page *stats; + int err; + + err = hv_map_stats_page(HV_STATS_OBJECT_HYPERVISOR, &identity, &stats); + if (err) { + pr_err("%s: failed to map hypervisor stats: %d\n", + __func__, err); + return ERR_PTR(err); + } + return stats; +} + +static int __init mshv_debugfs_hv_stats_create(struct dentry *parent) +{ + struct dentry *dentry; + u64 *stats; + int err; + + stats = mshv_hv_stats_map(); + if (IS_ERR(stats)) + return PTR_ERR(stats); + + dentry = debugfs_create_file("stats", 0400, parent, + stats, &hv_stats_fops); + if (IS_ERR(dentry)) { + err = PTR_ERR(dentry); + pr_err("%s: failed to create hypervisor stats dentry: %d\n", + __func__, err); + goto unmap_hv_stats; + } + + mshv_lps_count = stats[HV_HYPERVISOR_COUNTER_LOGICAL_PROCESSORS]; + + return 0; + +unmap_hv_stats: + mshv_hv_stats_unmap(); + return err; +} + +int mshv_debugfs_vp_create(struct mshv_vp *vp) +{ + struct mshv_partition *p = vp->vp_partition; + + if (!mshv_debugfs) + return 0; + + return vp_debugfs_create(p->pt_id, vp->vp_index, + vp->vp_stats_pages, + &vp->vp_stats_dentry, + p->pt_vp_dentry); +} + +void mshv_debugfs_vp_remove(struct mshv_vp *vp) +{ + if (!mshv_debugfs) + return; + + vp_debugfs_remove(vp->vp_stats_dentry); +} + +int mshv_debugfs_partition_create(struct mshv_partition *partition) +{ + int err; + + if (!mshv_debugfs) + return 0; + + err = partition_debugfs_create(partition->pt_id, + &partition->pt_vp_dentry, + &partition->pt_stats_dentry, + mshv_debugfs_partition); + if (err) + return err; + + return 0; +} + +void mshv_debugfs_partition_remove(struct mshv_partition *partition) +{ + if (!mshv_debugfs) + return; + + partition_debugfs_remove(partition->pt_id, + partition->pt_stats_dentry); +} + +int __init mshv_debugfs_init(void) +{ + int err; + + mshv_debugfs = debugfs_create_dir("mshv", NULL); + if (IS_ERR(mshv_debugfs)) { + err = PTR_ERR(mshv_debugfs); + mshv_debugfs = NULL; + pr_err("%s: failed to create debugfs directory\n", __func__); + return err; + } + + if (hv_root_partition()) { + err = mshv_debugfs_hv_stats_create(mshv_debugfs); + if (err) + goto remove_mshv_dir; + + err = mshv_debugfs_lp_create(mshv_debugfs); + if (err) + goto unmap_hv_stats; + } + + err = mshv_debugfs_parent_partition_create(); + if (err) + goto unmap_lp_stats; + + return 0; + +unmap_lp_stats: + if (hv_root_partition()) { + mshv_debugfs_lp_remove(); + mshv_debugfs_lp = NULL; + } +unmap_hv_stats: + if (hv_root_partition()) + mshv_hv_stats_unmap(); +remove_mshv_dir: + debugfs_remove_recursive(mshv_debugfs); + mshv_debugfs = NULL; + return err; +} + +void mshv_debugfs_exit(void) +{ + if (!mshv_debugfs) + return; + + mshv_debugfs_parent_partition_remove(); + + if (hv_root_partition()) { + mshv_debugfs_lp_remove(); + mshv_debugfs_lp = NULL; + mshv_hv_stats_unmap(); + } + + debugfs_remove_recursive(mshv_debugfs); + mshv_debugfs = NULL; + mshv_debugfs_partition = NULL; +} |
