From: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
To: Alexei Starovoitov <alexei.starovoitov@gmail.com>,
Steven Rostedt <rostedt@goodmis.org>,
Florent Revest <revest@chromium.org>
Cc: linux-trace-kernel@vger.kernel.org,
LKML <linux-kernel@vger.kernel.org>,
Martin KaFai Lau <martin.lau@linux.dev>,
bpf <bpf@vger.kernel.org>, Sven Schnelle <svens@linux.ibm.com>,
Alexei Starovoitov <ast@kernel.org>, Jiri Olsa <jolsa@kernel.org>,
Arnaldo Carvalho de Melo <acme@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
Alan Maguire <alan.maguire@oracle.com>,
Mark Rutland <mark.rutland@arm.com>,
Peter Zijlstra <peterz@infradead.org>,
Thomas Gleixner <tglx@linutronix.de>, Guo Ren <guoren@kernel.org>
Subject: [PATCH v10 29/36] bpf: Enable kprobe_multi feature if CONFIG_FPROBE is enabled
Date: Tue, 7 May 2024 23:13:41 +0900 [thread overview]
Message-ID: <171509122161.162236.2569574954668326512.stgit@devnote2> (raw)
In-Reply-To: <171509088006.162236.7227326999861366050.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Enable kprobe_multi feature if CONFIG_FPROBE is enabled. The pt_regs is
converted from ftrace_regs by ftrace_partial_regs(), thus some registers
may always returns 0. But it should be enough for function entry (access
arguments) and exit (access return value).
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Florent Revest <revest@chromium.org>
---
Changes in v9:
- Avoid wasting memory for bpf_kprobe_multi_pt_regs when
CONFIG_HAVE_PT_REGS_TO_FTRACE_REGS_CAST=y
---
kernel/trace/bpf_trace.c | 27 ++++++++++++++-------------
1 file changed, 14 insertions(+), 13 deletions(-)
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index e51a6ef87167..b779f4a83361 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -2577,7 +2577,7 @@ static int __init bpf_event_init(void)
fs_initcall(bpf_event_init);
#endif /* CONFIG_MODULES */
-#if defined(CONFIG_FPROBE) && defined(CONFIG_DYNAMIC_FTRACE_WITH_REGS)
+#ifdef CONFIG_FPROBE
struct bpf_kprobe_multi_link {
struct bpf_link link;
struct fprobe fp;
@@ -2600,6 +2600,13 @@ struct user_syms {
char *buf;
};
+#ifndef CONFIG_HAVE_PT_REGS_TO_FTRACE_REGS_CAST
+static DEFINE_PER_CPU(struct pt_regs, bpf_kprobe_multi_pt_regs);
+#define bpf_kprobe_multi_pt_regs_ptr() this_cpu_ptr(&bpf_kprobe_multi_pt_regs)
+#else
+#define bpf_kprobe_multi_pt_regs_ptr() (NULL)
+#endif
+
static int copy_user_syms(struct user_syms *us, unsigned long __user *usyms, u32 cnt)
{
unsigned long __user usymbol;
@@ -2792,13 +2799,14 @@ static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx)
static int
kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link,
- unsigned long entry_ip, struct pt_regs *regs)
+ unsigned long entry_ip, struct ftrace_regs *fregs)
{
struct bpf_kprobe_multi_run_ctx run_ctx = {
.link = link,
.entry_ip = entry_ip,
};
struct bpf_run_ctx *old_run_ctx;
+ struct pt_regs *regs;
int err;
if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) {
@@ -2809,6 +2817,7 @@ kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link,
migrate_disable();
rcu_read_lock();
+ regs = ftrace_partial_regs(fregs, bpf_kprobe_multi_pt_regs_ptr());
old_run_ctx = bpf_set_run_ctx(&run_ctx.run_ctx);
err = bpf_prog_run(link->link.prog, regs);
bpf_reset_run_ctx(old_run_ctx);
@@ -2826,13 +2835,9 @@ kprobe_multi_link_handler(struct fprobe *fp, unsigned long fentry_ip,
void *data)
{
struct bpf_kprobe_multi_link *link;
- struct pt_regs *regs = ftrace_get_regs(fregs);
-
- if (!regs)
- return 0;
link = container_of(fp, struct bpf_kprobe_multi_link, fp);
- kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs);
+ kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), fregs);
return 0;
}
@@ -2842,13 +2847,9 @@ kprobe_multi_link_exit_handler(struct fprobe *fp, unsigned long fentry_ip,
void *data)
{
struct bpf_kprobe_multi_link *link;
- struct pt_regs *regs = ftrace_get_regs(fregs);
-
- if (!regs)
- return;
link = container_of(fp, struct bpf_kprobe_multi_link, fp);
- kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs);
+ kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), fregs);
}
static int symbols_cmp_r(const void *a, const void *b, const void *priv)
@@ -3107,7 +3108,7 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr
kvfree(cookies);
return err;
}
-#else /* !CONFIG_FPROBE || !CONFIG_DYNAMIC_FTRACE_WITH_REGS */
+#else /* !CONFIG_FPROBE */
int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
{
return -EOPNOTSUPP;
next prev parent reply other threads:[~2024-05-07 14:13 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-07 14:08 [PATCH v10 00/36] tracing: fprobe: function_graph: Multi-function graph and fprobe on fgraph Masami Hiramatsu (Google)
2024-05-07 14:08 ` [PATCH v10 01/36] tracing: Add a comment about ftrace_regs definition Masami Hiramatsu (Google)
2024-05-23 23:10 ` Steven Rostedt
2024-05-24 1:09 ` Masami Hiramatsu
2024-05-07 14:08 ` [PATCH v10 02/36] tracing: Rename ftrace_regs_return_value to ftrace_regs_get_return_value Masami Hiramatsu (Google)
2024-05-07 14:08 ` [PATCH v10 03/36] x86: tracing: Add ftrace_regs definition in the header Masami Hiramatsu (Google)
2024-05-23 23:14 ` Steven Rostedt
2024-05-24 1:37 ` Masami Hiramatsu
2024-05-24 14:31 ` Steven Rostedt
2024-05-07 14:08 ` [PATCH v10 04/36] function_graph: Convert ret_stack to a series of longs Masami Hiramatsu (Google)
2024-05-07 14:08 ` [PATCH v10 05/36] fgraph: Use BUILD_BUG_ON() to make sure we have structures divisible by long Masami Hiramatsu (Google)
2024-05-07 14:09 ` [PATCH v10 06/36] function_graph: Add an array structure that will allow multiple callbacks Masami Hiramatsu (Google)
2024-05-07 14:09 ` [PATCH v10 07/36] function_graph: Allow multiple users to attach to function graph Masami Hiramatsu (Google)
2024-05-25 1:32 ` Steven Rostedt
2024-05-25 9:44 ` Masami Hiramatsu
2024-05-07 14:09 ` [PATCH v10 08/36] function_graph: Remove logic around ftrace_graph_entry and return Masami Hiramatsu (Google)
2024-05-07 14:09 ` [PATCH v10 09/36] ftrace/function_graph: Pass fgraph_ops to function graph callbacks Masami Hiramatsu (Google)
2024-05-07 14:09 ` [PATCH v10 10/36] ftrace: Allow function_graph tracer to be enabled in instances Masami Hiramatsu (Google)
2024-05-07 14:10 ` [PATCH v10 11/36] ftrace: Allow ftrace startup flags exist without dynamic ftrace Masami Hiramatsu (Google)
2024-05-07 14:10 ` [PATCH v10 12/36] function_graph: Have the instances use their own ftrace_ops for filtering Masami Hiramatsu (Google)
2024-05-07 14:10 ` [PATCH v10 13/36] function_graph: Use a simple LRU for fgraph_array index number Masami Hiramatsu (Google)
2024-05-07 14:10 ` [PATCH v10 14/36] function_graph: Add "task variables" per task for fgraph_ops Masami Hiramatsu (Google)
2024-05-07 14:10 ` [PATCH v10 15/36] function_graph: Move set_graph_function tests to shadow stack global var Masami Hiramatsu (Google)
2024-05-07 14:11 ` [PATCH v10 16/36] function_graph: Move graph depth stored data " Masami Hiramatsu (Google)
2024-05-07 14:11 ` [PATCH v10 17/36] function_graph: Move graph notrace bit " Masami Hiramatsu (Google)
2024-05-07 14:11 ` [PATCH v10 18/36] function_graph: Implement fgraph_reserve_data() and fgraph_retrieve_data() Masami Hiramatsu (Google)
2024-05-07 14:11 ` [PATCH v10 19/36] function_graph: Add selftest for passing local variables Masami Hiramatsu (Google)
2024-05-07 14:11 ` [PATCH v10 20/36] ftrace: Add multiple fgraph storage selftest Masami Hiramatsu (Google)
2024-05-07 14:12 ` [PATCH v10 21/36] function_graph: Pass ftrace_regs to entryfunc Masami Hiramatsu (Google)
2024-05-07 14:12 ` [PATCH v10 22/36] function_graph: Replace fgraph_ret_regs with ftrace_regs Masami Hiramatsu (Google)
2024-05-07 14:12 ` [PATCH v10 23/36] function_graph: Pass ftrace_regs to retfunc Masami Hiramatsu (Google)
2024-05-07 14:12 ` [PATCH v10 24/36] fprobe: Use ftrace_regs in fprobe entry handler Masami Hiramatsu (Google)
2024-05-07 14:12 ` [PATCH v10 25/36] fprobe: Use ftrace_regs in fprobe exit handler Masami Hiramatsu (Google)
2024-05-07 14:13 ` [PATCH v10 26/36] tracing: Add ftrace_partial_regs() for converting ftrace_regs to pt_regs Masami Hiramatsu (Google)
2024-05-07 14:13 ` [PATCH v10 27/36] tracing: Add ftrace_fill_perf_regs() for perf event Masami Hiramatsu (Google)
2024-05-07 14:13 ` [PATCH v10 28/36] tracing/fprobe: Enable fprobe events with CONFIG_DYNAMIC_FTRACE_WITH_ARGS Masami Hiramatsu (Google)
2024-05-07 14:13 ` Masami Hiramatsu (Google) [this message]
2024-05-07 14:13 ` [PATCH v10 30/36] ftrace: Add CONFIG_HAVE_FTRACE_GRAPH_FUNC Masami Hiramatsu (Google)
2024-05-07 14:14 ` [PATCH v10 31/36] fprobe: Rewrite fprobe on function-graph tracer Masami Hiramatsu (Google)
2024-05-07 14:14 ` [PATCH v10 32/36] tracing/fprobe: Remove nr_maxactive from fprobe Masami Hiramatsu (Google)
2024-05-07 14:14 ` [PATCH v10 33/36] selftests: ftrace: Remove obsolate maxactive syntax check Masami Hiramatsu (Google)
2024-05-07 14:14 ` [PATCH v10 34/36] selftests/ftrace: Add a test case for repeating register/unregister fprobe Masami Hiramatsu (Google)
2024-05-07 14:14 ` [PATCH v10 35/36] Documentation: probes: Update fprobe on function-graph tracer Masami Hiramatsu (Google)
2024-05-07 14:15 ` [PATCH v10 36/36] fgraph: Skip recording calltime/rettime if it is not nneeded Masami Hiramatsu (Google)
2024-05-24 22:41 ` [PATCH v10 00/36] tracing: fprobe: function_graph: Multi-function graph and fprobe on fgraph Steven Rostedt
2024-05-25 9:48 ` Masami Hiramatsu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=171509122161.162236.2569574954668326512.stgit@devnote2 \
--to=mhiramat@kernel.org \
--cc=acme@kernel.org \
--cc=alan.maguire@oracle.com \
--cc=alexei.starovoitov@gmail.com \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=guoren@kernel.org \
--cc=jolsa@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-trace-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=martin.lau@linux.dev \
--cc=peterz@infradead.org \
--cc=revest@chromium.org \
--cc=rostedt@goodmis.org \
--cc=svens@linux.ibm.com \
--cc=tglx@linutronix.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).