From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2B88A38E8BB; Mon, 29 Jun 2026 06:12:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782713577; cv=none; b=LYkjiro7Zd7R12KuHDIU6NNN1kw0dEuy+6CbDotWTKX7+cho6CUDfoktejZ2kYktUjqyvp0QFbbbzIXgeTuOyDVS2+EIOg9uX4/RGoEgBXAn7Tcda3v2MvA27Lf/vcv2u0IPNG6n06YjYnoM3zOxt8crVhBEJ6nFBbmUSB/a0ok= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782713577; c=relaxed/simple; bh=bK21rENjNQMrIYAU+B0smXVqv28Jv/SGncV2Pwlu8c0=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=bCETgu8PPcU8BBc706CMXlwWtP+4HMCwgZhBij0OZ+IXbZfGMeJJrU+V7/jB/ninBTo7Hl/QGyEojWdDtXifdGMAAFgGA1geno3tt5ph+ytGzyYfa3cvyRJkcFVvo2DEA8p8pae7AZTSbjtBPYiXnMQxvEyNXb6raXbQCFRdpJ4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 25B5C1F000E9; Mon, 29 Jun 2026 06:12:53 +0000 (UTC) From: "Masami Hiramatsu (Google)" To: Steven Rostedt , Mathieu Desnoyers Cc: Jonathan Corbet , Shuah Khan , Masami Hiramatsu , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: [PATCH v13 00/11] tracing/probes: Add more typecast features Date: Mon, 29 Jun 2026 15:12:51 +0900 Message-ID: <178271357142.1176915.7193483024740701480.stgit@devnote2> X-Mailer: git-send-email 2.43.0 User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Hi, Here is the 13th version of series to introduce more typecast features to probe events. The previous version is here: https://lore.kernel.org/all/178269068329.1161310.17763177188897860801.stgit@devnote2/ This version fixes a missed comma issue [8/11][10/11] pointed by Sashiko. This series extends BTF typecast feature and add more options: 1. Expanding BTF typecast to kprobe and fprobe. (currently only function entry/exit) 2. Introduce container_of like typecast. This adds a "assigned member" option to the typecast. (STRUCT,MEMBER)VAR->ANOTHER_MEMBER This casts VAR to STRUCT type but the VAR is as the address of STRUCT.MEMBER. In C, it is: container_of(VAR, STRUCT, MEMBER)->ANOTHER_MEMBER 3. Support nested typecast, e.g. (STRUCT)((STRUCT2)VAR->MEMBER2)->MEMBER the nest level must be smaller than 3. 4. Add $current variable to point "current" task_struct. This is useful with typecast, e.g. (task_struct)$current->pid 5. per-cpu dereference support. Intrdouce this_cpu_read(VAR) and this_cpu_ptr(VAR) to access per-cpu data on the current CPU (accessing other CPU data is not stable, because it can be changed.) You can access the member of per-cpu data structure using typecast like: (STRUCT)this_cpu_ptr(VAR)->MEMBER 6. Support event fields without $ prefix on eprobes. Now eprobe events can access its event fields. And added fetcharg dump feature (for debug) and updated test scripts to test part of them. Thanks, --- base-commit: c69b5f959286395e94c237ce6d7d4970bad7f6e3 Masami Hiramatsu (Google) (11): tracing/probes: Allow eprobe to use variable without $ prefix tracing/probes: Support dumping fetcharg program for debugging dynamic events tools/bootconfig: Ignore comment lines in dynamic_events/kprobe_events file perf/probe: Ignore comment lines in dynamic_events/kprobe_events file tracing/probes: Support typecast for various probe events tracing/probes: Support nested typecast tracing/probes: Type casting always involves nested calls tracing/probes: Support field specifier option for typecast tracing/probes: Add $current variable support tracing/probes: Add this_cpu_read() and this_cpu_ptr() dereference method to fetcharg tracing/probes: Add a new testcase for BTF typecasts Documentation/trace/eprobetrace.rst | 7 Documentation/trace/fprobetrace.rst | 10 Documentation/trace/kprobetrace.rst | 11 kernel/trace/Kconfig | 12 kernel/trace/trace.c | 8 kernel/trace/trace_eprobe.c | 2 kernel/trace/trace_fprobe.c | 2 kernel/trace/trace_kprobe.c | 2 kernel/trace/trace_probe.c | 585 ++++++++++++++++---- kernel/trace/trace_probe.h | 100 ++- kernel/trace/trace_probe_tmpl.h | 25 + kernel/trace/trace_uprobe.c | 3 samples/trace_events/trace-events-sample.c | 40 + samples/trace_events/trace-events-sample.h | 34 + tools/bootconfig/scripts/ftrace2bconf.sh | 2 tools/perf/util/probe-file.c | 2 .../ftrace/test.d/dynevent/btf_probe_event.tc | 51 ++ .../test.d/dynevent/btf_typecast_accepted.tc | 103 ++++ .../test.d/dynevent/eprobes_syntax_errors.tc | 12 .../ftrace/test.d/dynevent/fprobe_syntax_errors.tc | 12 .../ftrace/test.d/kprobe/kprobe_syntax_errors.tc | 12 .../ftrace/test.d/kprobe/uprobe_syntax_errors.tc | 5 22 files changed, 886 insertions(+), 154 deletions(-) create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/btf_probe_event.tc create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/btf_typecast_accepted.tc -- Masami Hiramatsu (Google)