__u64 ip[0]; /* /proc/sys/kernel/perf_event_max_stack */
};
+struct perf_callchain_entry_ctx {
+ struct perf_callchain_entry *entry;
+ u32 max_stack;
+ u32 nr;
+ short contexts;
+ bool contexts_maxed;
+};
+
struct perf_raw_record {
u32 size;
void *data;
/* Callchains */
DECLARE_PER_CPU(struct perf_callchain_entry, perf_callchain_entry);
-extern void perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs);
-extern void perf_callchain_kernel(struct perf_callchain_entry *entry, struct pt_regs *regs);
+extern void perf_callchain_user(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs);
+extern void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs);
extern struct perf_callchain_entry *
get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user,
- bool crosstask, bool add_mark);
+ u32 max_stack, bool crosstask, bool add_mark);
extern int get_callchain_buffers(void);
extern void put_callchain_buffers(void);
extern int sysctl_perf_event_max_stack;
+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 */
+ }
+}
-static inline int perf_callchain_store(struct perf_callchain_entry *entry, u64 ip)
+static inline int perf_callchain_store(struct perf_callchain_entry_ctx *ctx, u64 ip)
{
- if (entry->nr < sysctl_perf_event_max_stack) {
+ if (ctx->nr < ctx->max_stack && !ctx->contexts_maxed) {
+ struct perf_callchain_entry *entry = ctx->entry;
entry->ip[entry->nr++] = ip;
+ ++ctx->nr;
return 0;
} else {
return -1; /* no more room, stop walking the stack */