diff options
| author | Masami Hiramatsu (Google) <mhiramat@kernel.org> | 2023-06-06 21:39:56 +0900 |
|---|---|---|
| committer | Masami Hiramatsu (Google) <mhiramat@kernel.org> | 2023-06-06 21:39:56 +0900 |
| commit | b576e09701c7d045bbe5cd85d53e2f34426aa214 (patch) | |
| tree | 20d10ab0213b47f5640051cf45a6510c8f1d625a /kernel/trace/trace_probe.h | |
| parent | 1b8b0cd754cdbb54058165992456368495a695ac (diff) | |
tracing/probes: Support function parameters if BTF is available
Support function or tracepoint parameters by name if BTF support is enabled
and the event is for function entry (this feature can be used with kprobe-
events, fprobe-events and tracepoint probe events.)
Note that the BTF variable syntax does not require a prefix. If it starts
with an alphabetic character or an underscore ('_') without a prefix like
'$' and '%', it is considered as a BTF variable.
If you specify only the BTF variable name, the argument name will also
be the same name instead of 'arg*'.
# echo 'p vfs_read count pos' >> dynamic_events
# echo 'f vfs_write count pos' >> dynamic_events
# echo 't sched_overutilized_tp rd overutilized' >> dynamic_events
# cat dynamic_events
p:kprobes/p_vfs_read_0 vfs_read count=count pos=pos
f:fprobes/vfs_write__entry vfs_write count=count pos=pos
t:tracepoints/sched_overutilized_tp sched_overutilized_tp rd=rd overutilized=overutilized
Link: https://lore.kernel.org/all/168507474014.913472.16963996883278039183.stgit@mhiramat.roam.corp.google.com/
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Tested-by: Alan Maguire <alan.maguire@oracle.com>
Diffstat (limited to 'kernel/trace/trace_probe.h')
| -rw-r--r-- | kernel/trace/trace_probe.h | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index f622340ae171..7af121996ce9 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -23,6 +23,7 @@ #include <linux/limits.h> #include <linux/uaccess.h> #include <linux/bitops.h> +#include <linux/btf.h> #include <asm/bitsperlong.h> #include "trace.h" @@ -380,6 +381,9 @@ static inline bool tparg_is_function_entry(unsigned int flags) struct traceprobe_parse_context { struct trace_event_call *event; + const struct btf_param *params; + s32 nr_params; + const char *funcname; unsigned int flags; int offset; }; @@ -478,7 +482,10 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call, C(NO_EVENT_INFO, "This requires both group and event name to attach"),\ C(BAD_ATTACH_EVENT, "Attached event does not exist"),\ C(BAD_ATTACH_ARG, "Attached event does not have this field"),\ - C(NO_EP_FILTER, "No filter rule after 'if'"), + C(NO_EP_FILTER, "No filter rule after 'if'"), \ + C(NOSUP_BTFARG, "BTF is not available or not supported"), \ + C(NO_BTFARG, "This variable is not found at this probe point"),\ + C(NO_BTF_ENTRY, "No BTF entry for this probe point"), #undef C #define C(a, b) TP_ERR_##a |