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-rw-r--r--kernel/audit_tree.c18
-rw-r--r--kernel/bpf/arraymap.c20
-rw-r--r--kernel/bpf/core.c14
-rw-r--r--kernel/bpf/hashtab.c24
-rw-r--r--kernel/bpf/stackmap.c20
-rw-r--r--kernel/bpf/syscall.c34
-rw-r--r--kernel/bpf/verifier.c2
-rw-r--r--kernel/capability.c1
-rw-r--r--kernel/cgroup.c13
-rw-r--r--kernel/cpu.c24
-rw-r--r--kernel/events/core.c244
-rw-r--r--kernel/irq/irqdomain.c83
-rw-r--r--kernel/irq/msi.c4
-rw-r--r--kernel/jump_label.c7
-rw-r--r--kernel/memremap.c4
-rw-r--r--kernel/module.c55
-rw-r--r--kernel/panic.c4
-rw-r--r--kernel/pid_namespace.c10
-rw-r--r--kernel/power/suspend.c4
-rw-r--r--kernel/rcu/rcu.h1
-rw-r--r--kernel/rcu/tiny.c4
-rw-r--r--kernel/rcu/tiny_plugin.h9
-rw-r--r--kernel/rcu/tree.c33
-rw-r--r--kernel/rcu/tree_exp.h52
-rw-r--r--kernel/rcu/tree_plugin.h2
-rw-r--r--kernel/rcu/update.c38
-rw-r--r--kernel/signal.c4
-rw-r--r--kernel/sysctl.c1
-rw-r--r--kernel/time/tick-sched.c9
-rw-r--r--kernel/time/tick-sched.h2
-rw-r--r--kernel/trace/trace_hwlat.c8
-rw-r--r--kernel/trace/trace_kprobe.c2
-rw-r--r--kernel/ucount.c14
-rw-r--r--kernel/watchdog.c9
-rw-r--r--kernel/watchdog_hld.c3
35 files changed, 538 insertions, 238 deletions
diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c
index 8b1dde96a0fa..7b44195da81b 100644
--- a/kernel/audit_tree.c
+++ b/kernel/audit_tree.c
@@ -231,9 +231,11 @@ static void untag_chunk(struct node *p)
if (size)
new = alloc_chunk(size);
+ mutex_lock(&entry->group->mark_mutex);
spin_lock(&entry->lock);
if (chunk->dead || !entry->inode) {
spin_unlock(&entry->lock);
+ mutex_unlock(&entry->group->mark_mutex);
if (new)
free_chunk(new);
goto out;
@@ -251,6 +253,7 @@ static void untag_chunk(struct node *p)
list_del_rcu(&chunk->hash);
spin_unlock(&hash_lock);
spin_unlock(&entry->lock);
+ mutex_unlock(&entry->group->mark_mutex);
fsnotify_destroy_mark(entry, audit_tree_group);
goto out;
}
@@ -258,8 +261,8 @@ static void untag_chunk(struct node *p)
if (!new)
goto Fallback;
- fsnotify_duplicate_mark(&new->mark, entry);
- if (fsnotify_add_mark(&new->mark, new->mark.group, new->mark.inode, NULL, 1)) {
+ if (fsnotify_add_mark_locked(&new->mark, entry->group, entry->inode,
+ NULL, 1)) {
fsnotify_put_mark(&new->mark);
goto Fallback;
}
@@ -293,6 +296,7 @@ static void untag_chunk(struct node *p)
owner->root = new;
spin_unlock(&hash_lock);
spin_unlock(&entry->lock);
+ mutex_unlock(&entry->group->mark_mutex);
fsnotify_destroy_mark(entry, audit_tree_group);
fsnotify_put_mark(&new->mark); /* drop initial reference */
goto out;
@@ -309,6 +313,7 @@ Fallback:
put_tree(owner);
spin_unlock(&hash_lock);
spin_unlock(&entry->lock);
+ mutex_unlock(&entry->group->mark_mutex);
out:
fsnotify_put_mark(entry);
spin_lock(&hash_lock);
@@ -386,18 +391,21 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree)
chunk_entry = &chunk->mark;
+ mutex_lock(&old_entry->group->mark_mutex);
spin_lock(&old_entry->lock);
if (!old_entry->inode) {
/* old_entry is being shot, lets just lie */
spin_unlock(&old_entry->lock);
+ mutex_unlock(&old_entry->group->mark_mutex);
fsnotify_put_mark(old_entry);
free_chunk(chunk);
return -ENOENT;
}
- fsnotify_duplicate_mark(chunk_entry, old_entry);
- if (fsnotify_add_mark(chunk_entry, chunk_entry->group, chunk_entry->inode, NULL, 1)) {
+ if (fsnotify_add_mark_locked(chunk_entry, old_entry->group,
+ old_entry->inode, NULL, 1)) {
spin_unlock(&old_entry->lock);
+ mutex_unlock(&old_entry->group->mark_mutex);
fsnotify_put_mark(chunk_entry);
fsnotify_put_mark(old_entry);
return -ENOSPC;
@@ -413,6 +421,7 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree)
chunk->dead = 1;
spin_unlock(&chunk_entry->lock);
spin_unlock(&old_entry->lock);
+ mutex_unlock(&old_entry->group->mark_mutex);
fsnotify_destroy_mark(chunk_entry, audit_tree_group);
@@ -445,6 +454,7 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree)
spin_unlock(&hash_lock);
spin_unlock(&chunk_entry->lock);
spin_unlock(&old_entry->lock);
+ mutex_unlock(&old_entry->group->mark_mutex);
fsnotify_destroy_mark(old_entry, audit_tree_group);
fsnotify_put_mark(chunk_entry); /* drop initial reference */
fsnotify_put_mark(old_entry); /* pair to fsnotify_find mark_entry */
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index a2ac051c342f..3d55d95dcf49 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -11,7 +11,6 @@
*/
#include <linux/bpf.h>
#include <linux/err.h>
-#include <linux/vmalloc.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/filter.h>
@@ -56,7 +55,7 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
attr->value_size == 0 || attr->map_flags)
return ERR_PTR(-EINVAL);
- if (attr->value_size >= 1 << (KMALLOC_SHIFT_MAX - 1))
+ if (attr->value_size > KMALLOC_MAX_SIZE)
/* if value_size is bigger, the user space won't be able to
* access the elements.
*/
@@ -74,14 +73,10 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
if (array_size >= U32_MAX - PAGE_SIZE)
return ERR_PTR(-ENOMEM);
-
/* allocate all map elements and zero-initialize them */
- array = kzalloc(array_size, GFP_USER | __GFP_NOWARN);
- if (!array) {
- array = vzalloc(array_size);
- if (!array)
- return ERR_PTR(-ENOMEM);
- }
+ array = bpf_map_area_alloc(array_size);
+ if (!array)
+ return ERR_PTR(-ENOMEM);
/* copy mandatory map attributes */
array->map.map_type = attr->map_type;
@@ -97,7 +92,7 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
if (array_size >= U32_MAX - PAGE_SIZE ||
elem_size > PCPU_MIN_UNIT_SIZE || bpf_array_alloc_percpu(array)) {
- kvfree(array);
+ bpf_map_area_free(array);
return ERR_PTR(-ENOMEM);
}
out:
@@ -262,7 +257,7 @@ static void array_map_free(struct bpf_map *map)
if (array->map.map_type == BPF_MAP_TYPE_PERCPU_ARRAY)
bpf_array_free_percpu(array);
- kvfree(array);
+ bpf_map_area_free(array);
}
static const struct bpf_map_ops array_ops = {
@@ -319,7 +314,8 @@ static void fd_array_map_free(struct bpf_map *map)
/* make sure it's empty */
for (i = 0; i < array->map.max_entries; i++)
BUG_ON(array->ptrs[i] != NULL);
- kvfree(array);
+
+ bpf_map_area_free(array);
}
static void *fd_array_map_lookup_elem(struct bpf_map *map, void *key)
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 1eb4f1303756..503d4211988a 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -146,10 +146,11 @@ void __bpf_prog_free(struct bpf_prog *fp)
vfree(fp);
}
-int bpf_prog_calc_digest(struct bpf_prog *fp)
+int bpf_prog_calc_tag(struct bpf_prog *fp)
{
const u32 bits_offset = SHA_MESSAGE_BYTES - sizeof(__be64);
- u32 raw_size = bpf_prog_digest_scratch_size(fp);
+ u32 raw_size = bpf_prog_tag_scratch_size(fp);
+ u32 digest[SHA_DIGEST_WORDS];
u32 ws[SHA_WORKSPACE_WORDS];
u32 i, bsize, psize, blocks;
struct bpf_insn *dst;
@@ -162,7 +163,7 @@ int bpf_prog_calc_digest(struct bpf_prog *fp)
if (!raw)
return -ENOMEM;
- sha_init(fp->digest);
+ sha_init(digest);
memset(ws, 0, sizeof(ws));
/* We need to take out the map fd for the digest calculation
@@ -204,13 +205,14 @@ int bpf_prog_calc_digest(struct bpf_prog *fp)
*bits = cpu_to_be64((psize - 1) << 3);
while (blocks--) {
- sha_transform(fp->digest, todo, ws);
+ sha_transform(digest, todo, ws);
todo += SHA_MESSAGE_BYTES;
}
- result = (__force __be32 *)fp->digest;
+ result = (__force __be32 *)digest;
for (i = 0; i < SHA_DIGEST_WORDS; i++)
- result[i] = cpu_to_be32(fp->digest[i]);
+ result[i] = cpu_to_be32(digest[i]);
+ memcpy(fp->tag, result, sizeof(fp->tag));
vfree(raw);
return 0;
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index 34debc1a9641..a753bbe7df0a 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -13,7 +13,6 @@
#include <linux/bpf.h>
#include <linux/jhash.h>
#include <linux/filter.h>
-#include <linux/vmalloc.h>
#include "percpu_freelist.h"
#include "bpf_lru_list.h"
@@ -103,7 +102,7 @@ static void htab_free_elems(struct bpf_htab *htab)
free_percpu(pptr);
}
free_elems:
- vfree(htab->elems);
+ bpf_map_area_free(htab->elems);
}
static struct htab_elem *prealloc_lru_pop(struct bpf_htab *htab, void *key,
@@ -125,7 +124,8 @@ static int prealloc_init(struct bpf_htab *htab)
{
int err = -ENOMEM, i;
- htab->elems = vzalloc(htab->elem_size * htab->map.max_entries);
+ htab->elems = bpf_map_area_alloc(htab->elem_size *
+ htab->map.max_entries);
if (!htab->elems)
return -ENOMEM;
@@ -274,7 +274,7 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
*/
goto free_htab;
- if (htab->map.value_size >= (1 << (KMALLOC_SHIFT_MAX - 1)) -
+ if (htab->map.value_size >= KMALLOC_MAX_SIZE -
MAX_BPF_STACK - sizeof(struct htab_elem))
/* if value_size is bigger, the user space won't be able to
* access the elements via bpf syscall. This check also makes
@@ -320,14 +320,10 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
goto free_htab;
err = -ENOMEM;
- htab->buckets = kmalloc_array(htab->n_buckets, sizeof(struct bucket),
- GFP_USER | __GFP_NOWARN);
-
- if (!htab->buckets) {
- htab->buckets = vmalloc(htab->n_buckets * sizeof(struct bucket));
- if (!htab->buckets)
- goto free_htab;
- }
+ htab->buckets = bpf_map_area_alloc(htab->n_buckets *
+ sizeof(struct bucket));
+ if (!htab->buckets)
+ goto free_htab;
for (i = 0; i < htab->n_buckets; i++) {
INIT_HLIST_HEAD(&htab->buckets[i].head);
@@ -354,7 +350,7 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
free_extra_elems:
free_percpu(htab->extra_elems);
free_buckets:
- kvfree(htab->buckets);
+ bpf_map_area_free(htab->buckets);
free_htab:
kfree(htab);
return ERR_PTR(err);
@@ -1014,7 +1010,7 @@ static void htab_map_free(struct bpf_map *map)
prealloc_destroy(htab);
free_percpu(htab->extra_elems);
- kvfree(htab->buckets);
+ bpf_map_area_free(htab->buckets);
kfree(htab);
}
diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c
index 732ae16d12b7..be8519148c25 100644
--- a/kernel/bpf/stackmap.c
+++ b/kernel/bpf/stackmap.c
@@ -7,7 +7,6 @@
#include <linux/bpf.h>
#include <linux/jhash.h>
#include <linux/filter.h>
-#include <linux/vmalloc.h>
#include <linux/stacktrace.h>
#include <linux/perf_event.h>
#include "percpu_freelist.h"
@@ -32,7 +31,7 @@ static int prealloc_elems_and_freelist(struct bpf_stack_map *smap)
u32 elem_size = sizeof(struct stack_map_bucket) + smap->map.value_size;
int err;
- smap->elems = vzalloc(elem_size * smap->map.max_entries);
+ smap->elems = bpf_map_area_alloc(elem_size * smap->map.max_entries);
if (!smap->elems)
return -ENOMEM;
@@ -45,7 +44,7 @@ static int prealloc_elems_and_freelist(struct bpf_stack_map *smap)
return 0;
free_elems:
- vfree(smap->elems);
+ bpf_map_area_free(smap->elems);
return err;
}
@@ -76,12 +75,9 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr)
if (cost >= U32_MAX - PAGE_SIZE)
return ERR_PTR(-E2BIG);
- smap = kzalloc(cost, GFP_USER | __GFP_NOWARN);
- if (!smap) {
- smap = vzalloc(cost);
- if (!smap)
- return ERR_PTR(-ENOMEM);
- }
+ smap = bpf_map_area_alloc(cost);
+ if (!smap)
+ return ERR_PTR(-ENOMEM);
err = -E2BIG;
cost += n_buckets * (value_size + sizeof(struct stack_map_bucket));
@@ -112,7 +108,7 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr)
put_buffers:
put_callchain_buffers();
free_smap:
- kvfree(smap);
+ bpf_map_area_free(smap);
return ERR_PTR(err);
}
@@ -262,9 +258,9 @@ static void stack_map_free(struct bpf_map *map)
/* wait for bpf programs to complete before freeing stack map */
synchronize_rcu();
- vfree(smap->elems);
+ bpf_map_area_free(smap->elems);
pcpu_freelist_destroy(&smap->freelist);
- kvfree(smap);
+ bpf_map_area_free(smap);
put_callchain_buffers();
}
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index e89acea22ecf..19b6129eab23 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -12,6 +12,8 @@
#include <linux/bpf.h>
#include <linux/syscalls.h>
#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/mmzone.h>
#include <linux/anon_inodes.h>
#include <linux/file.h>
#include <linux/license.h>
@@ -49,6 +51,30 @@ void bpf_register_map_type(struct bpf_map_type_list *tl)
list_add(&tl->list_node, &bpf_map_types);
}
+void *bpf_map_area_alloc(size_t size)
+{
+ /* We definitely need __GFP_NORETRY, so OOM killer doesn't
+ * trigger under memory pressure as we really just want to
+ * fail instead.
+ */
+ const gfp_t flags = __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO;
+ void *area;
+
+ if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
+ area = kmalloc(size, GFP_USER | flags);
+ if (area != NULL)
+ return area;
+ }
+
+ return __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM | flags,
+ PAGE_KERNEL);
+}
+
+void bpf_map_area_free(void *area)
+{
+ kvfree(area);
+}
+
int bpf_map_precharge_memlock(u32 pages)
{
struct user_struct *user = get_current_user();
@@ -688,17 +714,17 @@ static int bpf_prog_release(struct inode *inode, struct file *filp)
static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
{
const struct bpf_prog *prog = filp->private_data;
- char prog_digest[sizeof(prog->digest) * 2 + 1] = { };
+ char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
- bin2hex(prog_digest, prog->digest, sizeof(prog->digest));
+ bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
seq_printf(m,
"prog_type:\t%u\n"
"prog_jited:\t%u\n"
- "prog_digest:\t%s\n"
+ "prog_tag:\t%s\n"
"memlock:\t%llu\n",
prog->type,
prog->jited,
- prog_digest,
+ prog_tag,
prog->pages * 1ULL << PAGE_SHIFT);
}
#endif
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 83ed2f8f6f22..cdc43b899f28 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -2936,7 +2936,7 @@ static int replace_map_fd_with_map_ptr(struct bpf_verifier_env *env)
int insn_cnt = env->prog->len;
int i, j, err;
- err = bpf_prog_calc_digest(env->prog);
+ err = bpf_prog_calc_tag(env->prog);
if (err)
return err;
diff --git a/kernel/capability.c b/kernel/capability.c
index a98e814f216f..f97fe77ceb88 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -318,6 +318,7 @@ bool has_capability(struct task_struct *t, int cap)
{
return has_ns_capability(t, &init_user_ns, cap);
}
+EXPORT_SYMBOL(has_capability);
/**
* has_ns_capability_noaudit - Does a task have a capability (unaudited)
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 2ee9ec3051b2..688dd02af985 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -5221,6 +5221,11 @@ err_free_css:
return ERR_PTR(err);
}
+/*
+ * The returned cgroup is fully initialized including its control mask, but
+ * it isn't associated with its kernfs_node and doesn't have the control
+ * mask applied.
+ */
static struct cgroup *cgroup_create(struct cgroup *parent)
{
struct cgroup_root *root = parent->root;
@@ -5288,11 +5293,6 @@ static struct cgroup *cgroup_create(struct cgroup *parent)
cgroup_propagate_control(cgrp);
- /* @cgrp doesn't have dir yet so the following will only create csses */
- ret = cgroup_apply_control_enable(cgrp);
- if (ret)
- goto out_destroy;
-
return cgrp;
out_cancel_ref:
@@ -5300,9 +5300,6 @@ out_cancel_ref:
out_free_cgrp:
kfree(cgrp);
return ERR_PTR(ret);
-out_destroy:
- cgroup_destroy_locked(cgrp);
- return ERR_PTR(ret);
}
static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
diff --git a/kernel/cpu.c b/kernel/cpu.c
index f75c4d031eeb..0a5f630f5c54 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -764,7 +764,6 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen,
{
struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu);
int prev_state, ret = 0;
- bool hasdied = false;
if (num_online_cpus() == 1)
return -EBUSY;
@@ -809,7 +808,6 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen,
cpuhp_kick_ap_work(cpu);
}
- hasdied = prev_state != st->state && st->state == CPUHP_OFFLINE;
out:
cpu_hotplug_done();
return ret;
@@ -1302,10 +1300,24 @@ static int cpuhp_cb_check(enum cpuhp_state state)
*/
static int cpuhp_reserve_state(enum cpuhp_state state)
{
- enum cpuhp_state i;
+ enum cpuhp_state i, end;
+ struct cpuhp_step *step;
- for (i = CPUHP_AP_ONLINE_DYN; i <= CPUHP_AP_ONLINE_DYN_END; i++) {
- if (!cpuhp_ap_states[i].name)
+ switch (state) {
+ case CPUHP_AP_ONLINE_DYN:
+ step = cpuhp_ap_states + CPUHP_AP_ONLINE_DYN;
+ end = CPUHP_AP_ONLINE_DYN_END;
+ break;
+ case CPUHP_BP_PREPARE_DYN:
+ step = cpuhp_bp_states + CPUHP_BP_PREPARE_DYN;
+ end = CPUHP_BP_PREPARE_DYN_END;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ for (i = state; i <= end; i++, step++) {
+ if (!step->name)
return i;
}
WARN(1, "No more dynamic states available for CPU hotplug\n");
@@ -1323,7 +1335,7 @@ static int cpuhp_store_callbacks(enum cpuhp_state state, const char *name,
mutex_lock(&cpuhp_state_mutex);
- if (state == CPUHP_AP_ONLINE_DYN) {
+ if (state == CPUHP_AP_ONLINE_DYN || state == CPUHP_BP_PREPARE_DYN) {
ret = cpuhp_reserve_state(state);
if (ret < 0)
goto out;
diff --git a/kernel/events/core.c b/kernel/events/core.c
index ab15509fab8c..e5aaa806702d 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -1469,7 +1469,6 @@ ctx_group_list(struct perf_event *event, struct perf_event_context *ctx)
static void
list_add_event(struct perf_event *event, struct perf_event_context *ctx)
{
-
lockdep_assert_held(&ctx->lock);
WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT);
@@ -1624,6 +1623,8 @@ static void perf_group_attach(struct perf_event *event)
{
struct perf_event *group_leader = event->group_leader, *pos;
+ lockdep_assert_held(&event->ctx->lock);
+
/*
* We can have double attach due to group movement in perf_event_open.
*/
@@ -1697,6 +1698,8 @@ static void perf_group_detach(struct perf_event *event)
struct perf_event *sibling, *tmp;
struct list_head *list = NULL;
+ lockdep_assert_held(&event->ctx->lock);
+
/*
* We can have double detach due to exit/hot-unplug + close.
*/
@@ -1895,9 +1898,29 @@ __perf_remove_from_context(struct perf_event *event,
*/
static void perf_remove_from_context(struct perf_event *event, unsigned long flags)
{
- lockdep_assert_held(&event->ctx->mutex);
+ struct perf_event_context *ctx = event->ctx;
+
+ lockdep_assert_held(&ctx->mutex);
event_function_call(event, __perf_remove_from_context, (void *)flags);
+
+ /*
+ * The above event_function_call() can NO-OP when it hits
+ * TASK_TOMBSTONE. In that case we must already have been detached
+ * from the context (by perf_event_exit_event()) but the grouping
+ * might still be in-tact.
+ */
+ WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT);
+ if ((flags & DETACH_GROUP) &&
+ (event->attach_state & PERF_ATTACH_GROUP)) {
+ /*
+ * Since in that case we cannot possibly be scheduled, simply
+ * detach now.
+ */
+ raw_spin_lock_irq(&ctx->lock);
+ perf_group_detach(event);
+ raw_spin_unlock_irq(&ctx->lock);
+ }
}
/*
@@ -2249,7 +2272,7 @@ static int __perf_install_in_context(void *info)
struct perf_event_context *ctx = event->ctx;
struct perf_cpu_context *cpuctx = __get_cpu_context(ctx);
struct perf_event_context *task_ctx = cpuctx->task_ctx;
- bool activate = true;
+ bool reprogram = true;
int ret = 0;
raw_spin_lock(&cpuctx->ctx.lock);
@@ -2257,27 +2280,26 @@ static int __perf_install_in_context(void *info)
raw_spin_lock(&ctx->lock);
task_ctx = ctx;
- /* If we're on the wrong CPU, try again */
- if (task_cpu(ctx->task) != smp_processor_id()) {
- ret = -ESRCH;
- goto unlock;
- }
+ reprogram = (ctx->task == current);
/*
- * If we're on the right CPU, see if the task we target is
- * current, if not we don't have to activate the ctx, a future
- * context switch will do that for us.
+ * If the task is running, it must be running on this CPU,
+ * otherwise we cannot reprogram things.
+ *
+ * If its not running, we don't care, ctx->lock will
+ * serialize against it becoming runnable.
*/
- if (ctx->task != current)
- activate = false;
- else
- WARN_ON_ONCE(cpuctx->task_ctx && cpuctx->task_ctx != ctx);
+ if (task_curr(ctx->task) && !reprogram) {
+ ret = -ESRCH;
+ goto unlock;
+ }
+ WARN_ON_ONCE(reprogram && cpuctx->task_ctx && cpuctx->task_ctx != ctx);
} else if (task_ctx) {
raw_spin_lock(&task_ctx->lock);
}
- if (activate) {
+ if (reprogram) {
ctx_sched_out(ctx, cpuctx, EVENT_TIME);
add_event_to_ctx(event, ctx);
ctx_resched(cpuctx, task_ctx);
@@ -2328,13 +2350,36 @@ perf_install_in_context(struct perf_event_context *ctx,
/*
* Installing events is tricky because we cannot rely on ctx->is_active
* to be set in case this is the nr_events 0 -> 1 transition.
+ *
+ * Instead we use task_curr(), which tells us if the task is running.
+ * However, since we use task_curr() outside of rq::lock, we can race
+ * against the actual state. This means the result can be wrong.
+ *
+ * If we get a false positive, we retry, this is harmless.
+ *
+ * If we get a false negative, things are complicated. If we are after
+ * perf_event_context_sched_in() ctx::lock will serialize us, and the
+ * value must be correct. If we're before, it doesn't matter since
+ * perf_event_context_sched_in() will program the counter.
+ *
+ * However, this hinges on the remote context switch having observed
+ * our task->perf_event_ctxp[] store, such that it will in fact take
+ * ctx::lock in perf_event_context_sched_in().
+ *
+ * We do this by task_function_call(), if the IPI fails to hit the task
+ * we know any future context switch of task must see the
+ * perf_event_ctpx[] store.
*/
-again:
+
/*
- * Cannot use task_function_call() because we need to run on the task's
- * CPU regardless of whether its current or not.
+ * This smp_mb() orders the task->perf_event_ctxp[] store with the
+ * task_cpu() load, such that if the IPI then does not find the task
+ * running, a future context switch of that task must observe the
+ * store.
*/
- if (!cpu_function_call(task_cpu(task), __perf_install_in_context, event))
+ smp_mb();
+again:
+ if (!task_function_call(task, __perf_install_in_context, event))
return;
raw_spin_lock_irq(&ctx->lock);
@@ -2348,12 +2393,16 @@ again:
raw_spin_unlock_irq(&ctx->lock);
return;
}
- raw_spin_unlock_irq(&ctx->lock);
/*
- * Since !ctx->is_active doesn't mean anything, we must IPI
- * unconditionally.
+ * If the task is not running, ctx->lock will avoid it becoming so,
+ * thus we can safely install the event.
*/
- goto again;
+ if (task_curr(task)) {
+ raw_spin_unlock_irq(&ctx->lock);
+ goto again;
+ }
+ add_event_to_ctx(event, ctx);
+ raw_spin_unlock_irq(&ctx->lock);
}
/*
@@ -6583,6 +6632,27 @@ static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)
char *buf = NULL;
char *name;
+ if (vma->vm_flags & VM_READ)
+ prot |= PROT_READ;
+ if (vma->vm_flags & VM_WRITE)
+ prot |= PROT_WRITE;
+ if (vma->vm_flags & VM_EXEC)
+ prot |= PROT_EXEC;
+
+ if (vma->vm_flags & VM_MAYSHARE)
+ flags = MAP_SHARED;
+ else
+ flags = MAP_PRIVATE;
+
+ if (vma->vm_flags & VM_DENYWRITE)
+ flags |= MAP_DENYWRITE;
+ if (vma->vm_flags & VM_MAYEXEC)
+ flags |= MAP_EXECUTABLE;
+ if (vma->vm_flags & VM_LOCKED)
+ flags |= MAP_LOCKED;
+ if (vma->vm_flags & VM_HUGETLB)
+ flags |= MAP_HUGETLB;
+
if (file) {
struct inode *inode;
dev_t dev;
@@ -6609,27 +6679,6 @@ static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)
maj = MAJOR(dev);
min = MINOR(dev);
- if (vma->vm_flags & VM_READ)
- prot |= PROT_READ;
- if (vma->vm_flags & VM_WRITE)
- prot |= PROT_WRITE;
- if (vma->vm_flags & VM_EXEC)
- prot |= PROT_EXEC;
-
- if (vma->vm_flags & VM_MAYSHARE)
- flags = MAP_SHARED;
- else
- flags = MAP_PRIVATE;
-
- if (vma->vm_flags & VM_DENYWRITE)
- flags |= MAP_DENYWRITE;
- if (vma->vm_flags & VM_MAYEXEC)
- flags |= MAP_EXECUTABLE;
- if (vma->vm_flags & VM_LOCKED)
- flags |= MAP_LOCKED;
- if (vma->vm_flags & VM_HUGETLB)
- flags |= MAP_HUGETLB;
-
goto got_name;
} else {
if (vma->vm_ops && vma->vm_ops->name) {
@@ -7034,25 +7083,12 @@ static void perf_log_itrace_start(struct perf_event *event)
perf_output_end(&handle);
}
-/*
- * Generic event overflow handling, sampling.
- */
-
-static int __perf_event_overflow(struct perf_event *event,
- int throttle, struct perf_sample_data *data,
- struct pt_regs *regs)
+static int
+__perf_event_account_interrupt(struct perf_event *event, int throttle)
{
- int events = atomic_read(&event->event_limit);
struct hw_perf_event *hwc = &event->hw;
- u64 seq;
int ret = 0;
-
- /*
- * Non-sampling counters might still use the PMI to fold short
- * hardware counters, ignore those.
- */
- if (unlikely(!is_sampling_event(event)))
- return 0;
+ u64 seq;
seq = __this_cpu_read(perf_throttled_seq);
if (seq != hwc->interrupts_seq) {
@@ -7080,6 +7116,34 @@ static int __perf_event_overflow(struct perf_event *event,
perf_adjust_period(event, delta, hwc->last_period, true);
}
+ return ret;
+}
+
+int perf_event_account_interrupt(struct perf_event *event)
+{
+ return __perf_event_account_interrupt(event, 1);
+}
+
+/*
+ * Generic event overflow handling, sampling.
+ */
+
+static int __perf_event_overflow(struct perf_event *event,
+ int throttle, struct perf_sample_data *data,
+ struct pt_regs *regs)
+{
+ int events = atomic_read(&event->event_limit);
+ int ret = 0;
+
+ /*
+ * Non-sampling counters might still use the PMI to fold short
+ * hardware counters, ignore those.
+ */
+ if (unlikely(!is_sampling_event(event)))
+ return 0;
+
+ ret = __perf_event_account_interrupt(event, throttle);
+
/*
* XXX