A new perf type PERF_TYPE_PROBE is added to allow creating [k,u]probe with perf_event_open. These [k,u]probe are associated with the file decriptor created by perf_event_open, thus are easy to clean when the file descriptor is destroyed.
Struct probe_desc and two flags, is_uprobe and is_return, are added to describe the probe being created with perf_event_open. Note: We use type __u64 for pointer probe_desc instead of __aligned_u64. The reason here is to avoid changing the size of struct perf_event_attr, and breaking new-kernel-old-utility scenario. To avoid alignment problem with the pointer, we will (in the following patches) copy probe_desc to __aligned_u64 before using it as pointer. Signed-off-by: Song Liu <songliubrav...@fb.com> Reviewed-by: Yonghong Song <y...@fb.com> Reviewed-by: Josef Bacik <jba...@fb.com> Acked-by: Alexei Starovoitov <a...@kernel.org> --- include/uapi/linux/perf_event.h | 35 +++++++++++++++++++++++++++++++++-- 1 file changed, 33 insertions(+), 2 deletions(-) diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h index 362493a..cc42d59 100644 --- a/include/uapi/linux/perf_event.h +++ b/include/uapi/linux/perf_event.h @@ -33,6 +33,7 @@ enum perf_type_id { PERF_TYPE_HW_CACHE = 3, PERF_TYPE_RAW = 4, PERF_TYPE_BREAKPOINT = 5, + PERF_TYPE_PROBE = 6, PERF_TYPE_MAX, /* non-ABI */ }; @@ -299,6 +300,29 @@ enum perf_event_read_format { #define PERF_ATTR_SIZE_VER4 104 /* add: sample_regs_intr */ #define PERF_ATTR_SIZE_VER5 112 /* add: aux_watermark */ +#define MAX_PROBE_FUNC_NAME_LEN 64 +/* + * Describe a kprobe or uprobe for PERF_TYPE_PROBE. + * perf_event_attr.probe_desc will point to this structure. is_uprobe + * and is_return are used to differentiate different types of probe + * (k/u, probe/retprobe). + * + * The two unions should be used as follows: + * For uprobe: use path and offset; + * For kprobe: if func is empty, use addr + * if func is not emtpy, use func and offset + */ +struct probe_desc { + union { + __aligned_u64 func; + __aligned_u64 path; + }; + union { + __aligned_u64 addr; + __u64 offset; + }; +}; + /* * Hardware event_id to monitor via a performance monitoring event: * @@ -320,7 +344,10 @@ struct perf_event_attr { /* * Type specific configuration information. */ - __u64 config; + union { + __u64 config; + __u64 probe_desc; /* ptr to struct probe_desc */ + }; union { __u64 sample_period; @@ -370,7 +397,11 @@ struct perf_event_attr { context_switch : 1, /* context switch data */ write_backward : 1, /* Write ring buffer from end to beginning */ namespaces : 1, /* include namespaces data */ - __reserved_1 : 35; + + /* For PERF_TYPE_PROBE */ + is_uprobe : 1, /* 0: kprobe, 1: uprobe */ + is_return : 1, /* 0: probe, 1: retprobe */ + __reserved_1 : 33; union { __u32 wakeup_events; /* wakeup every n events */ -- 2.9.5