diff options
| author | Dan Williams <dan.j.williams@intel.com> | 2019-03-11 20:37:55 +0100 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2019-03-11 20:37:55 +0100 |
| commit | 4083014e32699af04a8e6eaa4855b08dba36a47a (patch) | |
| tree | fa37f9f9691fe64ca8a3c0cdc0315dc12462e6e4 /kernel/bpf/syscall.c | |
| parent | Merge branch 'for-5.1/libnvdimm-start-pad' into libnvdimm-for-next (diff) | |
| parent | nfit/ars: Avoid stale ARS results (diff) | |
| download | linux-4083014e32699af04a8e6eaa4855b08dba36a47a.tar.xz linux-4083014e32699af04a8e6eaa4855b08dba36a47a.zip | |
Merge branch 'for-5.1/nfit/ars' into libnvdimm-for-next
Merge several updates to the ARS implementation. Highlights include:
* Support retrieval of short-ARS results if the ARS state is "requires
continuation", and even if the "no_init_ars" module parameter is
specified.
* Allow busy-polling of the kernel ARS state by allowing root to reset
the exponential back-off timer.
* Filter potentially stale ARS results by tracking query-ARS relative to
the previous start-ARS.
Diffstat (limited to 'kernel/bpf/syscall.c')
| -rw-r--r-- | kernel/bpf/syscall.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index b155cd17c1bd..8577bb7f8be6 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -713,8 +713,13 @@ static int map_lookup_elem(union bpf_attr *attr) if (bpf_map_is_dev_bound(map)) { err = bpf_map_offload_lookup_elem(map, key, value); - } else if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || - map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { + goto done; + } + + preempt_disable(); + this_cpu_inc(bpf_prog_active); + if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || + map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { err = bpf_percpu_hash_copy(map, key, value); } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { err = bpf_percpu_array_copy(map, key, value); @@ -744,7 +749,10 @@ static int map_lookup_elem(union bpf_attr *attr) } rcu_read_unlock(); } + this_cpu_dec(bpf_prog_active); + preempt_enable(); +done: if (err) goto free_value; |