diff options
author | David S. Miller <davem@davemloft.net> | 2018-05-21 16:01:54 -0400 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2018-05-21 16:01:54 -0400 |
commit | 6f6e434aa267a6030477876d89444fe3a6b7a48d (patch) | |
tree | 67755c422f1e85451aa646eae21d4c6f3f389d9f /kernel | |
parent | 44c752fe584d8b9f6e0756ecffa8691677471862 (diff) | |
parent | 6741c4bb389da103c0d79ad1961884628900bfe6 (diff) |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
S390 bpf_jit.S is removed in net-next and had changes in 'net',
since that code isn't used any more take the removal.
TLS data structures split the TX and RX components in 'net-next',
put the new struct members from the bug fix in 'net' into the RX
part.
The 'net-next' tree had some reworking of how the ERSPAN code works in
the GRE tunneling code, overlapping with a one-line headroom
calculation fix in 'net'.
Overlapping changes in __sock_map_ctx_update_elem(), keep the bits
that read the prog members via READ_ONCE() into local variables
before using them.
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/bpf/core.c | 100 | ||||
-rw-r--r-- | kernel/bpf/sockmap.c | 18 | ||||
-rw-r--r-- | kernel/events/ring_buffer.c | 7 | ||||
-rw-r--r-- | kernel/kthread.c | 50 | ||||
-rw-r--r-- | kernel/locking/rwsem-xadd.c | 19 | ||||
-rw-r--r-- | kernel/locking/rwsem.c | 2 | ||||
-rw-r--r-- | kernel/locking/rwsem.h | 30 | ||||
-rw-r--r-- | kernel/module.c | 5 | ||||
-rw-r--r-- | kernel/sched/autogroup.c | 7 | ||||
-rw-r--r-- | kernel/sched/core.c | 56 | ||||
-rw-r--r-- | kernel/sched/deadline.c | 4 | ||||
-rw-r--r-- | kernel/sched/fair.c | 59 | ||||
-rw-r--r-- | kernel/sched/rt.c | 2 | ||||
-rw-r--r-- | kernel/sched/sched.h | 5 | ||||
-rw-r--r-- | kernel/signal.c | 17 | ||||
-rw-r--r-- | kernel/stop_machine.c | 19 | ||||
-rw-r--r-- | kernel/time/tick-broadcast.c | 8 |
17 files changed, 223 insertions, 185 deletions
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 2194c6a9df42..b574dddc05b8 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -219,47 +219,84 @@ int bpf_prog_calc_tag(struct bpf_prog *fp) return 0; } -static void bpf_adj_branches(struct bpf_prog *prog, u32 pos, u32 delta) +static int bpf_adj_delta_to_imm(struct bpf_insn *insn, u32 pos, u32 delta, + u32 curr, const bool probe_pass) { + const s64 imm_min = S32_MIN, imm_max = S32_MAX; + s64 imm = insn->imm; + + if (curr < pos && curr + imm + 1 > pos) + imm += delta; + else if (curr > pos + delta && curr + imm + 1 <= pos + delta) + imm -= delta; + if (imm < imm_min || imm > imm_max) + return -ERANGE; + if (!probe_pass) + insn->imm = imm; + return 0; +} + +static int bpf_adj_delta_to_off(struct bpf_insn *insn, u32 pos, u32 delta, + u32 curr, const bool probe_pass) +{ + const s32 off_min = S16_MIN, off_max = S16_MAX; + s32 off = insn->off; + + if (curr < pos && curr + off + 1 > pos) + off += delta; + else if (curr > pos + delta && curr + off + 1 <= pos + delta) + off -= delta; + if (off < off_min || off > off_max) + return -ERANGE; + if (!probe_pass) + insn->off = off; + return 0; +} + +static int bpf_adj_branches(struct bpf_prog *prog, u32 pos, u32 delta, + const bool probe_pass) +{ + u32 i, insn_cnt = prog->len + (probe_pass ? delta : 0); struct bpf_insn *insn = prog->insnsi; - u32 i, insn_cnt = prog->len; - bool pseudo_call; - u8 code; - int off; + int ret = 0; for (i = 0; i < insn_cnt; i++, insn++) { + u8 code; + + /* In the probing pass we still operate on the original, + * unpatched image in order to check overflows before we + * do any other adjustments. Therefore skip the patchlet. + */ + if (probe_pass && i == pos) { + i += delta + 1; + insn++; + } code = insn->code; - if (BPF_CLASS(code) != BPF_JMP) - continue; - if (BPF_OP(code) == BPF_EXIT) + if (BPF_CLASS(code) != BPF_JMP || + BPF_OP(code) == BPF_EXIT) continue; + /* Adjust offset of jmps if we cross patch boundaries. */ if (BPF_OP(code) == BPF_CALL) { - if (insn->src_reg == BPF_PSEUDO_CALL) - pseudo_call = true; - else + if (insn->src_reg != BPF_PSEUDO_CALL) continue; + ret = bpf_adj_delta_to_imm(insn, pos, delta, i, + probe_pass); } else { - pseudo_call = false; + ret = bpf_adj_delta_to_off(insn, pos, delta, i, + probe_pass); } - off = pseudo_call ? insn->imm : insn->off; - - /* Adjust offset of jmps if we cross boundaries. */ - if (i < pos && i + off + 1 > pos) - off += delta; - else if (i > pos + delta && i + off + 1 <= pos + delta) - off -= delta; - - if (pseudo_call) - insn->imm = off; - else - insn->off = off; + if (ret) + break; } + + return ret; } struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off, const struct bpf_insn *patch, u32 len) { u32 insn_adj_cnt, insn_rest, insn_delta = len - 1; + const u32 cnt_max = S16_MAX; struct bpf_prog *prog_adj; /* Since our patchlet doesn't expand the image, we're done. */ @@ -270,6 +307,15 @@ struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off, insn_adj_cnt = prog->len + insn_delta; + /* Reject anything that would potentially let the insn->off + * target overflow when we have excessive program expansions. + * We need to probe here before we do any reallocation where + * we afterwards may not fail anymore. + */ + if (insn_adj_cnt > cnt_max && + bpf_adj_branches(prog, off, insn_delta, true)) + return NULL; + /* Several new instructions need to be inserted. Make room * for them. Likely, there's no need for a new allocation as * last page could have large enough tailroom. @@ -295,7 +341,11 @@ struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off, sizeof(*patch) * insn_rest); memcpy(prog_adj->insnsi + off, patch, sizeof(*patch) * len); - bpf_adj_branches(prog_adj, off, insn_delta); + /* We are guaranteed to not fail at this point, otherwise + * the ship has sailed to reverse to the original state. An + * overflow cannot happen at this point. + */ + BUG_ON(bpf_adj_branches(prog_adj, off, insn_delta, false)); return prog_adj; } diff --git a/kernel/bpf/sockmap.c b/kernel/bpf/sockmap.c index c6de1393df63..cd832250a478 100644 --- a/kernel/bpf/sockmap.c +++ b/kernel/bpf/sockmap.c @@ -1729,11 +1729,11 @@ static int __sock_map_ctx_update_elem(struct bpf_map *map, * we increment the refcnt. If this is the case abort with an * error. */ - verdict = bpf_prog_inc_not_zero(progs->bpf_verdict); + verdict = bpf_prog_inc_not_zero(verdict); if (IS_ERR(verdict)) return PTR_ERR(verdict); - parse = bpf_prog_inc_not_zero(progs->bpf_parse); + parse = bpf_prog_inc_not_zero(parse); if (IS_ERR(parse)) { bpf_prog_put(verdict); return PTR_ERR(parse); @@ -1741,12 +1741,12 @@ static int __sock_map_ctx_update_elem(struct bpf_map *map, } if (tx_msg) { - tx_msg = bpf_prog_inc_not_zero(progs->bpf_tx_msg); + tx_msg = bpf_prog_inc_not_zero(tx_msg); if (IS_ERR(tx_msg)) { - if (verdict) - bpf_prog_put(verdict); - if (parse) + if (parse && verdict) { bpf_prog_put(parse); + bpf_prog_put(verdict); + } return PTR_ERR(tx_msg); } } @@ -1826,10 +1826,10 @@ out_free: kfree(e); smap_release_sock(psock, sock); out_progs: - if (verdict) - bpf_prog_put(verdict); - if (parse) + if (parse && verdict) { bpf_prog_put(parse); + bpf_prog_put(verdict); + } if (tx_msg) bpf_prog_put(tx_msg); write_unlock_bh(&sock->sk_callback_lock); diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index 6c6b3c48db71..1d8ca9ea9979 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -14,6 +14,7 @@ #include <linux/slab.h> #include <linux/circ_buf.h> #include <linux/poll.h> +#include <linux/nospec.h> #include "internal.h" @@ -867,8 +868,10 @@ perf_mmap_to_page(struct ring_buffer *rb, unsigned long pgoff) return NULL; /* AUX space */ - if (pgoff >= rb->aux_pgoff) - return virt_to_page(rb->aux_pages[pgoff - rb->aux_pgoff]); + if (pgoff >= rb->aux_pgoff) { + int aux_pgoff = array_index_nospec(pgoff - rb->aux_pgoff, rb->aux_nr_pages); + return virt_to_page(rb->aux_pages[aux_pgoff]); + } } return __perf_mmap_to_page(rb, pgoff); diff --git a/kernel/kthread.c b/kernel/kthread.c index cd50e99202b0..2017a39ab490 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -55,7 +55,6 @@ enum KTHREAD_BITS { KTHREAD_IS_PER_CPU = 0, KTHREAD_SHOULD_STOP, KTHREAD_SHOULD_PARK, - KTHREAD_IS_PARKED, }; static inline void set_kthread_struct(void *kthread) @@ -177,14 +176,12 @@ void *kthread_probe_data(struct task_struct *task) static void __kthread_parkme(struct kthread *self) { - __set_current_state(TASK_PARKED); - while (test_bit(KTHREAD_SHOULD_PARK, &self->flags)) { - if (!test_and_set_bit(KTHREAD_IS_PARKED, &self->flags)) - complete(&self->parked); + for (;;) { + set_current_state(TASK_PARKED); + if (!test_bit(KTHREAD_SHOULD_PARK, &self->flags)) + break; schedule(); - __set_current_state(TASK_PARKED); } - clear_bit(KTHREAD_IS_PARKED, &self->flags); __set_current_state(TASK_RUNNING); } @@ -194,6 +191,11 @@ void kthread_parkme(void) } EXPORT_SYMBOL_GPL(kthread_parkme); +void kthread_park_complete(struct task_struct *k) +{ + complete(&to_kthread(k)->parked); +} + static int kthread(void *_create) { /* Copy data: it's on kthread's stack */ @@ -450,22 +452,15 @@ void kthread_unpark(struct task_struct *k) { struct kthread *kthread = to_kthread(k); - clear_bit(KTHREAD_SHOULD_PARK, &kthread->flags); /* - * We clear the IS_PARKED bit here as we don't wait - * until the task has left the park code. So if we'd - * park before that happens we'd see the IS_PARKED bit - * which might be about to be cleared. + * Newly created kthread was parked when the CPU was offline. + * The binding was lost and we need to set it again. */ - if (test_and_clear_bit(KTHREAD_IS_PARKED, &kthread->flags)) { - /* - * Newly created kthread was parked when the CPU was offline. - * The binding was lost and we need to set it again. - */ - if (test_bit(KTHREAD_IS_PER_CPU, &kthread->flags)) - __kthread_bind(k, kthread->cpu, TASK_PARKED); - wake_up_state(k, TASK_PARKED); - } + if (test_bit(KTHREAD_IS_PER_CPU, &kthread->flags)) + __kthread_bind(k, kthread->cpu, TASK_PARKED); + + clear_bit(KTHREAD_SHOULD_PARK, &kthread->flags); + wake_up_state(k, TASK_PARKED); } EXPORT_SYMBOL_GPL(kthread_unpark); @@ -488,12 +483,13 @@ int kthread_park(struct task_struct *k) if (WARN_ON(k->flags & PF_EXITING)) return -ENOSYS; - if (!test_bit(KTHREAD_IS_PARKED, &kthread->flags)) { - set_bit(KTHREAD_SHOULD_PARK, &kthread->flags); - if (k != current) { - wake_up_process(k); - wait_for_completion(&kthread->parked); - } + if (WARN_ON_ONCE(test_bit(KTHREAD_SHOULD_PARK, &kthread->flags))) + return -EBUSY; + + set_bit(KTHREAD_SHOULD_PARK, &kthread->flags); + if (k != current) { + wake_up_process(k); + wait_for_completion(&kthread->parked); } return 0; diff --git a/kernel/locking/rwsem-xadd.c b/kernel/locking/rwsem-xadd.c index e795908f3607..a90336779375 100644 --- a/kernel/locking/rwsem-xadd.c +++ b/kernel/locking/rwsem-xadd.c @@ -352,16 +352,15 @@ static inline bool rwsem_can_spin_on_owner(struct rw_semaphore *sem) struct task_struct *owner; bool ret = true; + BUILD_BUG_ON(!rwsem_has_anonymous_owner(RWSEM_OWNER_UNKNOWN)); + if (need_resched()) return false; rcu_read_lock(); owner = READ_ONCE(sem->owner); - if (!rwsem_owner_is_writer(owner)) { - /* - * Don't spin if the rwsem is readers owned. - */ - ret = !rwsem_owner_is_reader(owner); + if (!owner || !is_rwsem_owner_spinnable(owner)) { + ret = !owner; /* !owner is spinnable */ goto done; } @@ -382,11 +381,11 @@ static noinline bool rwsem_spin_on_owner(struct rw_semaphore *sem) { struct task_struct *owner = READ_ONCE(sem->owner); - if (!rwsem_owner_is_writer(owner)) - goto out; + if (!is_rwsem_owner_spinnable(owner)) + return false; rcu_read_lock(); - while (sem->owner == owner) { + while (owner && (READ_ONCE(sem->owner) == owner)) { /* * Ensure we emit the owner->on_cpu, dereference _after_ * checking sem->owner still matches owner, if that fails, @@ -408,12 +407,12 @@ static noinline bool rwsem_spin_on_owner(struct rw_semaphore *sem) cpu_relax(); } rcu_read_unlock(); -out: + /* * If there is a new owner or the owner is not set, we continue * spinning. */ - return !rwsem_owner_is_reader(READ_ONCE(sem->owner)); + return is_rwsem_owner_spinnable(READ_ONCE(sem->owner)); } static bool rwsem_optimistic_spin(struct rw_semaphore *sem) diff --git a/kernel/locking/rwsem.c b/kernel/locking/rwsem.c index 30465a2f2b6c..bc1e507be9ff 100644 --- a/kernel/locking/rwsem.c +++ b/kernel/locking/rwsem.c @@ -221,5 +221,3 @@ void up_read_non_owner(struct rw_semaphore *sem) EXPORT_SYMBOL(up_read_non_owner); #endif - - diff --git a/kernel/locking/rwsem.h b/kernel/locking/rwsem.h index a17cba8d94bb..b9d0e72aa80f 100644 --- a/kernel/locking/rwsem.h +++ b/kernel/locking/rwsem.h @@ -1,20 +1,24 @@ /* SPDX-License-Identifier: GPL-2.0 */ /* * The owner field of the rw_semaphore structure will be set to - * RWSEM_READ_OWNED when a reader grabs the lock. A writer will clear + * RWSEM_READER_OWNED when a reader grabs the lock. A writer will clear * the owner field when it unlocks. A reader, on the other hand, will * not touch the owner field when it unlocks. * - * In essence, the owner field now has the following 3 states: + * In essence, the owner field now has the following 4 states: * 1) 0 * - lock is free or the owner hasn't set the field yet * 2) RWSEM_READER_OWNED * - lock is currently or previously owned by readers (lock is free * or not set by owner yet) - * 3) Other non-zero value - * - a writer owns the lock + * 3) RWSEM_ANONYMOUSLY_OWNED bit set with some other bits set as well + * - lock is owned by an anonymous writer, so spinning on the lock + * owner should be disabled. + * 4) Other non-zero value + * - a writer owns the lock and other writers can spin on the lock owner. */ -#define RWSEM_READER_OWNED ((struct task_struct *)1UL) +#define RWSEM_ANONYMOUSLY_OWNED (1UL << 0) +#define RWSEM_READER_OWNED ((struct task_struct *)RWSEM_ANONYMOUSLY_OWNED) #ifdef CONFIG_DEBUG_RWSEMS # define DEBUG_RWSEMS_WARN_ON(c) DEBUG_LOCKS_WARN_ON(c) @@ -51,14 +55,22 @@ static inline void rwsem_set_reader_owned(struct rw_semaphore *sem) WRITE_ONCE(sem->owner, RWSEM_READER_OWNED); } -static inline bool rwsem_owner_is_writer(struct task_struct *owner) +/* + * Return true if the a rwsem waiter can spin on the rwsem's owner + * and steal the lock, i.e. the lock is not anonymously owned. + * N.B. !owner is considered spinnable. + */ +static inline bool is_rwsem_owner_spinnable(struct task_struct *owner) { - return owner && owner != RWSEM_READER_OWNED; + return !((unsigned long)owner & RWSEM_ANONYMOUSLY_OWNED); } -static inline bool rwsem_owner_is_reader(struct task_struct *owner) +/* + * Return true if rwsem is owned by an anonymous writer or readers. + */ +static inline bool rwsem_has_anonymous_owner(struct task_struct *owner) { - return owner == RWSEM_READER_OWNED; + return (unsigned long)owner & RWSEM_ANONYMOUSLY_OWNED; } #else static inline void rwsem_set_owner(struct rw_semaphore *sem) diff --git a/kernel/module.c b/kernel/module.c index ce8066b88178..c9bea7f2b43e 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -3517,6 +3517,11 @@ static noinline int do_init_module(struct module *mod) * walking this with preempt disabled. In all the failure paths, we * call synchronize_sched(), but we don't want to slow down the success * path, so use actual RCU here. + * Note that module_alloc() on most architectures creates W+X page + * mappings which won't be cleaned up until do_free_init() runs. Any + * code such as mark_rodata_ro() which depends on those mappings to + * be cleaned up needs to sync with the queued work - ie + * rcu_barrier_sched() */ call_rcu_sched(&freeinit->rcu, do_free_init); mutex_unlock(&module_mutex); diff --git a/kernel/sched/autogroup.c b/kernel/sched/autogroup.c index 6be6c575b6cd..2d4ff5353ded 100644 --- a/kernel/sched/autogroup.c +++ b/kernel/sched/autogroup.c @@ -2,6 +2,7 @@ /* * Auto-group scheduling implementation: */ +#include <linux/nospec.h> #include "sched.h" unsigned int __read_mostly sysctl_sched_autogroup_enabled = 1; @@ -209,7 +210,7 @@ int proc_sched_autogroup_set_nice(struct task_struct *p, int nice) static unsigned long next = INITIAL_JIFFIES; struct autogroup *ag; unsigned long shares; - int err; + int err, idx; if (nice < MIN_NICE || nice > MAX_NICE) return -EINVAL; @@ -227,7 +228,9 @@ int proc_sched_autogroup_set_nice(struct task_struct *p, int nice) next = HZ / 10 + jiffies; ag = autogroup_task_get(p); - shares = scale_load(sched_prio_to_weight[nice + 20]); + + idx = array_index_nospec(nice + 20, 40); + shares = scale_load(sched_prio_to_weight[idx]); down_write(&ag->lock); err = sched_group_set_shares(ag->tg, shares); diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 5e10aaeebfcc..092f7c4de903 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -7,6 +7,9 @@ */ #include "sched.h" +#include <linux/kthread.h> +#include <linux/nospec.h> + #include <asm/switch_to.h> #include <asm/tlb.h> @@ -2718,20 +2721,28 @@ static struct rq *finish_task_switch(struct task_struct *prev) membarrier_mm_sync_core_before_usermode(mm); mmdrop(mm); } - if (unlikely(prev_state == TASK_DEAD)) { - if (prev->sched_class->task_dead) - prev->sched_class->task_dead(prev); + if (unlikely(prev_state & (TASK_DEAD|TASK_PARKED))) { + switch (prev_state) { + case TASK_DEAD: + if (prev->sched_class->task_dead) + prev->sched_class->task_dead(prev); - /* - * Remove function-return probe instances associated with this - * task and put them back on the free list. - */ - kprobe_flush_task(prev); + /* + * Remove function-return probe instances associated with this + * task and put them back on the free list. + */ + kprobe_flush_task(prev); + + /* Task is done with its stack. */ + put_task_stack(prev); - /* Task is done with its stack. */ - put_task_stack(prev); + put_task_struct(prev); + break; - put_task_struct(prev); + case TASK_PARKED: + kthread_park_complete(prev); + break; + } } tick_nohz_task_switch(); @@ -3498,23 +3509,8 @@ static void __sched notrace __schedule(bool preempt) void __noreturn do_task_dead(void) { - /* - * The setting of TASK_RUNNING by try_to_wake_up() may be delayed - * when the following two conditions become true. - * - There is race condition of mmap_sem (It is acquired by - * exit_mm()), and - * - SMI occurs before setting TASK_RUNINNG. - * (or hypervisor of virtual machine switches to other guest) - * As a result, we may become TASK_RUNNING after becoming TASK_DEAD - * - * To avoid it, we have to wait for releasing tsk->pi_lock which - * is held by try_to_wake_up() - */ - raw_spin_lock_irq(¤t->pi_lock); - raw_spin_unlock_irq(¤t->pi_lock); - /* Causes final put_task_struct in finish_task_switch(): */ - __set_current_state(TASK_DEAD); + set_special_state(TASK_DEAD); /* Tell freezer to ignore us: */ current->flags |= PF_NOFREEZE; @@ -6928,11 +6924,15 @@ static int cpu_weight_nice_write_s64(struct cgroup_subsys_state *css, struct cftype *cft, s64 nice) { unsigned long weight; + int idx; if (nice < MIN_NICE || nice > MAX_NICE) return -ERANGE; - weight = sched_prio_to_weight[NICE_TO_PRIO(nice) - MAX_RT_PRIO]; + idx = NICE_TO_PRIO(nice) - MAX_RT_PRIO; + idx = array_index_nospec(idx, 40); + weight = sched_prio_to_weight[idx]; + return sched_group_set_shares(css_tg(css), scale_load(weight)); } #endif diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index e7b3008b85bb..1356afd1eeb6 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -1117,7 +1117,7 @@ extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq); * should be larger than 2^(64 - 20 - 8), which is more than 64 seconds. * So, overflow is not an issue here. */ -u64 grub_reclaim(u64 delta, struct rq *rq, struct sched_dl_entity *dl_se) +static u64 grub_reclaim(u64 delta, struct rq *rq, struct sched_dl_entity *dl_se) { u64 u_inact = rq->dl.this_bw - rq->dl.running_bw; /* Utot - Uact */ u64 u_act; @@ -2731,8 +2731,6 @@ bool dl_cpu_busy(unsigned int cpu) #endif #ifdef CONFIG_SCHED_DEBUG -extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq); - void print_dl_stats(struct seq_file *m, int cpu) { print_dl_rq(m, cpu, &cpu_rq(cpu)->dl); diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 54dc31e7ab9b..79f574dba096 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -1854,7 +1854,6 @@ static int task_numa_migrate(struct task_struct *p) static void numa_migrate_preferred(struct task_struct *p) { unsigned long interval = HZ; - unsigned long numa_migrate_retry; /* This task has no NUMA fault statistics yet */ if (unlikely(p->numa_preferred_nid == -1 || !p->numa_faults)) @@ -1862,18 +1861,7 @@ static void numa_migrate_preferred(struct task_struct *p) /* Periodically retry migrating the task to the preferred node */ interval = min(interval, msecs_to_jiffies(p->numa_scan_period) / 16); - numa_migrate_retry = jiffies + interval; - - /* - * Check that the new retry threshold is after the current one. If - * the retry is in the future, it implies that wake_affine has - * temporarily asked NUMA balancing to backoff from placement. - */ - if (numa_migrate_retry > p->numa_migrate_retry) - return; - - /* Safe to try placing the task on the preferred node */ - p->numa_migrate_retry = numa_migrate_retry; + p->numa_migrate_retry = jiffies + interval; /* Success if task is already running on preferred CPU */ if (task_node(p) == p->numa_preferred_nid) @@ -5922,48 +5910,6 @@ wake_affine_weight(struct sched_domain *sd, struct task_struct *p, return this_eff_load < prev_eff_load ? this_cpu : nr_cpumask_bits; } -#ifdef CONFIG_NUMA_BALANCING -static void -update_wa_numa_placement(struct task_struct *p, int prev_cpu, int target) -{ - unsigned long interval; - - if (!static_branch_likely(&sched_numa_balancing)) - return; - - /* If balancing has no preference then continue gathering data */ - if (p->numa_preferred_nid == -1) - return; - - /* - * If the wakeup is not affecting locality then it is neutral from - * the perspective of NUMA balacing so continue gathering data. - */ - if (cpu_to_node(prev_cpu) == cpu_to_node(target)) - return; - - /* - * Temporarily prevent NUMA balancing trying to place waker/wakee after - * wakee has been moved by wake_affine. This will potentially allow - * related tasks to converge and update their data placement. The - * 4 * numa_scan_period is to allow the two-pass filter to migrate - * hot data to the wakers node. - */ - interval = max(sysctl_numa_balancing_scan_delay, - p->numa_scan_period << 2); - p->numa_migrate_retry = jiffies + msecs_to_jiffies(interval); - - interval = max(sysctl_numa_balancing_scan_delay, - current->numa_scan_period << 2); - current->numa_migrate_retry = jiffies + msecs_to_jiffies(interval); -} -#else -static void -update_wa_numa_placement(struct task_struct *p, int prev_cpu, int target) -{ -} -#endif - static int wake_affine(struct sched_domain *sd, struct task_struct *p, int this_cpu, int prev_cpu, int sync) { @@ -5979,7 +5925,6 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, if (target == nr_cpumask_bits) return prev_cpu; - update_wa_numa_placement(p, prev_cpu, target); schedstat_inc(sd->ttwu_move_affine); schedstat_inc(p->se.statistics.nr_wakeups_affine); return target; @@ -9847,6 +9792,7 @@ static int idle_balance(struct rq *this_rq, struct rq_flags *rf) if (curr_cost > this_rq->max_idle_balance_cost) this_rq->max_idle_balance_cost = curr_cost; +out: /* * While browsing the domains, we released the rq lock, a task could * have been enqueued in the meantime. Since we're not going idle, @@ -9855,7 +9801,6 @@ static int idle_balance(struct rq *this_rq, struct rq_flags *rf) if (this_rq->cfs.h_nr_running && !pulled_task) pulled_task = 1; -out: /* Move the next balance forward */ if (time_after(this_rq->next_balance, next_balance)) this_rq->next_balance = next_balance; diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 7aef6b4e885a..ef3c4e6f5345 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -2701,8 +2701,6 @@ int sched_rr_handler(struct ctl_table *table, int write, } #ifdef CONFIG_SCHED_DEBUG -extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq); - void print_rt_stats(struct seq_file *m, int cpu) { rt_rq_iter_t iter; diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 15750c222ca2..1f0a4bc6a39d 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -2025,8 +2025,9 @@ extern bool sched_debug_enabled; extern void print_cfs_stats(struct seq_file *m, int cpu); extern void print_rt_stats(struct seq_file *m, int cpu); extern void print_dl_stats(struct seq_file *m, int cpu); -extern void -print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); +extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); +extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq); +extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq); #ifdef CONFIG_NUMA_BALANCING extern void show_numa_stats(struct task_struct *p, struct seq_file *m); diff --git a/kernel/signal.c b/kernel/signal.c index d4ccea599692..9c33163a6165 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -1961,14 +1961,27 @@ static void ptrace_stop(int exit_code, int why, int clear_code, siginfo_t *info) return; } + set_special_state(TASK_TRACED); + /* * We're committing to trapping. TRACED should be visible before * TRAPPING is cleared; otherwise, the tracer might fail do_wait(). * Also, transition to TRACED and updates to ->jobctl should be * atomic with respect to siglock and should be done after the arch * hook as siglock is released and regrabbed across it. + * + * TRACER TRACEE + * + * ptrace_attach() + * [L] wait_on_bit(JOBCTL_TRAPPING) [S] set_special_state(TRACED) + * do_wait() + * set_current_state() smp_wmb(); + * ptrace_do_wait() + * wait_task_stopped() + * task_stopped_code() + * [L] task_is_traced() [S] task_clear_jobctl_trapping(); */ - set_current_state(TASK_TRACED); + smp_wmb(); current->last_siginfo = info; current->exit_code = exit_code; @@ -2176,7 +2189,7 @@ static bool do_signal_stop(int signr) if (task_participate_group_stop(current)) notify = CLD_STOPPED; - __set_current_state(TASK_STOPPED); + set_special_state(TASK_STOPPED); spin_unlock_irq(¤t->sighand->siglock); /* diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index b7591261652d..64c0291b579c 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -21,6 +21,7 @@ #include <linux/smpboot.h> #include <linux/atomic.h> #include <linux/nmi.h> +#include <linux/sched/wake_q.h> /* * Structure to determine completion condition and record errors. May @@ -65,27 +66,31 @@ static void cpu_stop_signal_done(struct cpu_stop_done *done) } static void __cpu_stop_queue_work(struct cpu_stopper *stopper, - struct cpu_stop_work *work) + struct cpu_stop_work *work, + struct wake_q_head *wakeq) { list_add_tail(&work->list, &stopper->works); - wake_up_process(stopper->thread); + wake_q_add(wakeq, stopper->thread); } /* queue @work to @stopper. if offline, @work is completed immediately */ static bool cpu_stop_queue_work(unsigned int cpu, struct cpu_stop_work *work) { struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu); + DEFINE_WAKE_Q(wakeq); unsigned long flags; bool enabled; spin_lock_irqsave(&stopper->lock, flags); enabled = stopper->enabled; if (enabled) - __cpu_stop_queue_work(stopper, work); + __cpu_stop_queue_work(stopper, work, &wakeq); else if (work->done) cpu_stop_signal_done(work->done); spin_unlock_irqrestore(&stopper->lock, flags); + wake_up_q(&wakeq); + return enabled; } @@ -229,6 +234,7 @@ static int cpu_stop_queue_two_works(int cpu1, struct cpu_stop_work *work1, { struct cpu_stopper *stopper1 = per_cpu_ptr(&cpu_stopper, cpu1); struct cpu_stopper *stopper2 = per_cpu_ptr(&cpu_stopper, cpu2); + DEFINE_WAKE_Q(wakeq); int err; retry: spin_lock_irq(&stopper1->lock); @@ -252,8 +258,8 @@ retry: goto unlock; err = 0; - __cpu_stop_queue_work(stopper1, work1); - __cpu_stop_queue_work(stopper2, work2); + __cpu_stop_queue_work(stopper1, work1, &wakeq); + __cpu_stop_queue_work(stopper2, work2, &wakeq); unlock: spin_unlock(&stopper2->lock); spin_unlock_irq(&stopper1->lock); @@ -263,6 +269,9 @@ unlock: cpu_relax(); goto retry; } + + wake_up_q(&wakeq); + return err; } /** diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index b398c2ea69b2..aa2094d5dd27 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -612,6 +612,14 @@ static void tick_handle_oneshot_broadcast(struct clock_event_device *dev) now = ktime_get(); /* Find all expired events */ for_each_cpu(cpu, tick_broadcast_oneshot_mask) { + /* + * Required for !SMP because for_each_cpu() reports + * unconditionally CPU0 as set on UP kernels. + */ + if (!IS_ENABLED(CONFIG_SMP) && + cpumask_empty(tick_broadcast_oneshot_mask)) + break; + td = &per_cpu(tick_cpu_device, cpu); if (td->evtdev->next_event <= now) { cpumask_set_cpu(cpu, tmpmask); |