summaryrefslogtreecommitdiff
path: root/kernel/trace
diff options
context:
space:
mode:
authorPeter Zijlstra <peterz@infradead.org>2024-09-03 10:46:00 -0700
committerPeter Zijlstra <peterz@infradead.org>2024-09-05 16:56:14 +0200
commit04b01625da130c7521b768996cd5e48052198b97 (patch)
treed9f6d4adae5de1747d91f31fc70a9558c19e6127 /kernel/trace
parentcc01bd044e6a521d2cd128f685ee8d23ef0067f2 (diff)
perf/uprobe: split uprobe_unregister()
With uprobe_unregister() having grown a synchronize_srcu(), it becomes fairly slow to call. Esp. since both users of this API call it in a loop. Peel off the sync_srcu() and do it once, after the loop. We also need to add uprobe_unregister_sync() into uprobe_register()'s error handling path, as we need to be careful about returning to the caller before we have a guarantee that partially attached consumer won't be called anymore. This is an unlikely slow path and this should be totally fine to be slow in the case of a failed attach. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: "Peter Zijlstra (Intel)" <peterz@infradead.org> Co-developed-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20240903174603.3554182-6-andrii@kernel.org
Diffstat (limited to 'kernel/trace')
-rw-r--r--kernel/trace/bpf_trace.c5
-rw-r--r--kernel/trace/trace_uprobe.c6
2 files changed, 9 insertions, 2 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index c99bf0617602..ac0a01cc8634 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -3184,7 +3184,10 @@ static void bpf_uprobe_unregister(struct bpf_uprobe *uprobes, u32 cnt)
u32 i;
for (i = 0; i < cnt; i++)
- uprobe_unregister(uprobes[i].uprobe, &uprobes[i].consumer);
+ uprobe_unregister_nosync(uprobes[i].uprobe, &uprobes[i].consumer);
+
+ if (cnt)
+ uprobe_unregister_sync();
}
static void bpf_uprobe_multi_link_release(struct bpf_link *link)
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 7eb79e0a5352..f7443e996b1b 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -1097,6 +1097,7 @@ static int trace_uprobe_enable(struct trace_uprobe *tu, filter_func_t filter)
static void __probe_event_disable(struct trace_probe *tp)
{
struct trace_uprobe *tu;
+ bool sync = false;
tu = container_of(tp, struct trace_uprobe, tp);
WARN_ON(!uprobe_filter_is_empty(tu->tp.event->filter));
@@ -1105,9 +1106,12 @@ static void __probe_event_disable(struct trace_probe *tp)
if (!tu->uprobe)
continue;
- uprobe_unregister(tu->uprobe, &tu->consumer);
+ uprobe_unregister_nosync(tu->uprobe, &tu->consumer);
+ sync = true;
tu->uprobe = NULL;
}
+ if (sync)
+ uprobe_unregister_sync();
}
static int probe_event_enable(struct trace_event_call *call,