Re: [PATCH v10 perf, bpf-next 1/9] perf, bpf: Introduce PERF_RECORD_KSYMBOL
From: Peter Zijlstra <peterz@infradead.org>
Date: 2019-01-17 12:48:36
Also in:
lkml
On Wed, Jan 16, 2019 at 08:29:23AM -0800, Song Liu wrote:
+/* callback function to generate ksymbol name */ +typedef int (perf_ksymbol_get_name_f)(char *name, int name_len, void *data); +extern void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, + bool unregister, + perf_ksymbol_get_name_f get_name, void *data); +
I'm not liking the getname thing.. I know that's what BPF does, but can we please do that in the caller or something?
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h@@ -1114,11 +1114,8 @@ static inline void perf_event_task_sched extern void perf_event_mmap(struct vm_area_struct *vma); -/* callback function to generate ksymbol name */ -typedef int (perf_ksymbol_get_name_f)(char *name, int name_len, void *data); extern void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, - bool unregister, - perf_ksymbol_get_name_f get_name, void *data); + bool unregister, const char *name); extern struct perf_guest_info_callbacks *perf_guest_cbs; extern int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *callbacks);
@@ -1341,11 +1338,8 @@ static inline int perf_unregister_guest_ static inline void perf_event_mmap(struct vm_area_struct *vma) { } -typedef int (perf_ksymbol_get_name_f)(char *name, int name_len, void *data); static inline void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, - bool unregister, - perf_ksymbol_get_name_f get_name, - void *data) { } + bool unregister, const char *name) { } static inline void perf_event_exec(void) { } static inline void perf_event_comm(struct task_struct *tsk, bool exec) { } static inline void perf_event_namespaces(struct task_struct *tsk) { } --- a/kernel/events/core.c +++ b/kernel/events/core.c
@@ -7698,8 +7698,7 @@ static void perf_event_ksymbol_output(st perf_output_end(&handle); } -void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister, - perf_ksymbol_get_name_f get_name, void *data) +void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister, const char *sym) { struct perf_ksymbol_event ksymbol_event; char name[KSYM_NAME_LEN];
@@ -7713,7 +7712,7 @@ void perf_event_ksymbol(u16 ksym_type, u ksym_type == PERF_RECORD_KSYMBOL_TYPE_UNKNOWN) goto err; - get_name(name, KSYM_NAME_LEN, data); + strlcpy(name, sym, KSYM_NAME_LEN); name_len = strlen(name) + 1; while (!IS_ALIGNED(name_len, sizeof(u64))) name[name_len++] = '\0';