diff options
Diffstat (limited to 'Documentation/trace')
| -rw-r--r-- | Documentation/trace/uprobetracer.txt | 22 |
1 files changed, 20 insertions, 2 deletions
diff --git a/Documentation/trace/uprobetracer.txt b/Documentation/trace/uprobetracer.txt index eae40a003eec..24ce6823a09e 100644 --- a/Documentation/trace/uprobetracer.txt +++ b/Documentation/trace/uprobetracer.txt @@ -5,7 +5,7 @@ Overview -------- Uprobe based trace events are similar to kprobe based trace events. -To enable this feature, build your kernel with CONFIG_UPROBE_EVENTS=y. +To enable this feature, build your kernel with CONFIG_UPROBE_EVENT=y. Similar to the kprobe-event tracer, this doesn't need to be activated via current_tracer. Instead of that, add probe points via @@ -68,7 +68,25 @@ in the object. We can see the events that are registered by looking at the uprobe_events file. # cat uprobe_events - p:uprobes/p_zsh_0x46420 /bin/zsh:0x0000000000046420 + p:uprobes/p_zsh_0x46420 /bin/zsh:0x00046420 arg1=%ip arg2=%ax + +The format of events can be seen by viewing the file events/uprobes/p_zsh_0x46420/format + + # cat events/uprobes/p_zsh_0x46420/format + name: p_zsh_0x46420 + ID: 922 + format: + field:unsigned short common_type; offset:0; size:2; signed:0; + field:unsigned char common_flags; offset:2; size:1; signed:0; + field:unsigned char common_preempt_count; offset:3; size:1; signed:0; + field:int common_pid; offset:4; size:4; signed:1; + field:int common_padding; offset:8; size:4; signed:1; + + field:unsigned long __probe_ip; offset:12; size:4; signed:0; + field:u32 arg1; offset:16; size:4; signed:0; + field:u32 arg2; offset:20; size:4; signed:0; + + print fmt: "(%lx) arg1=%lx arg2=%lx", REC->__probe_ip, REC->arg1, REC->arg2 Right after definition, each event is disabled by default. For tracing these events, you need to enable it by: |