+extern int sysctl_perf_event_max_contexts_per_stack;
+
+static inline int perf_callchain_store_context(struct perf_callchain_entry_ctx *ctx, u64 ip)
+{
+ if (ctx->contexts < sysctl_perf_event_max_contexts_per_stack) {
+ struct perf_callchain_entry *entry = ctx->entry;
+ entry->ip[entry->nr++] = ip;
+ ++ctx->contexts;
+ return 0;
+ } else {
+ ctx->contexts_maxed = true;
+ return -1; /* no more room, stop walking the stack */
+ }
+}