From: Punit Agrawal <punitagrawal@gmail.com>
To: mhiramat@kernel.org, naveen.n.rao@linux.ibm.com,
anil.s.keshavamurthy@intel.com, davem@davemloft.net
Cc: Punit Agrawal <punitagrawal@gmail.com>,
linux-kernel@vger.kernel.org, guoren@kernel.org,
linux-csky@vger.kernel.org
Subject: [RFC PATCH 3/5] kprobe: Simplify prepare_kprobe() by dropping redundant version
Date: Wed, 9 Jun 2021 19:50:17 +0900 [thread overview]
Message-ID: <20210609105019.3626677-4-punitagrawal@gmail.com> (raw)
In-Reply-To: <20210609105019.3626677-1-punitagrawal@gmail.com>
The function prepare_kprobe() is called during kprobe registration and
is responsible for ensuring any architecture related preparation for
the kprobe is done before returning.
One of two versions of prepare_kprobe() is chosen depending on the
availability of KPROBE_ON_FTRACE in the kernel configuration.
Simplify the code by dropping the version when KPROBE_ON_FTRACE is not
selected - instead relying on kprobe_ftrace() to return false when
KPROBE_ON_FTRACE is not set.
No functional change.
Signed-off-by: Punit Agrawal <punitagrawal@gmail.com>
---
include/linux/kprobes.h | 5 +++++
kernel/kprobes.c | 23 +++++++++--------------
2 files changed, 14 insertions(+), 14 deletions(-)
diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index 1883a4a9f16a..771013bab18a 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -362,6 +362,11 @@ static inline void wait_for_kprobe_optimizer(void) { }
extern void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *ops, struct ftrace_regs *fregs);
extern int arch_prepare_kprobe_ftrace(struct kprobe *p);
+#else
+static inline int arch_prepare_kprobe_ftrace(struct kprobe *p)
+{
+ return -EINVAL;
+}
#endif
int arch_check_ftrace_location(struct kprobe *p);
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 1a11d3c411bf..54d37d4ab897 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1022,15 +1022,6 @@ static struct ftrace_ops kprobe_ipmodify_ops __read_mostly = {
static int kprobe_ipmodify_enabled;
static int kprobe_ftrace_enabled;
-/* Must ensure p->addr is really on ftrace */
-static int prepare_kprobe(struct kprobe *p)
-{
- if (!kprobe_ftrace(p))
- return arch_prepare_kprobe(p);
-
- return arch_prepare_kprobe_ftrace(p);
-}
-
/* Caller must lock kprobe_mutex */
static int __arm_kprobe_ftrace(struct kprobe *p, struct ftrace_ops *ops,
int *cnt)
@@ -1102,11 +1093,6 @@ static int disarm_kprobe_ftrace(struct kprobe *p)
ipmodify ? &kprobe_ipmodify_enabled : &kprobe_ftrace_enabled);
}
#else /* !CONFIG_KPROBES_ON_FTRACE */
-static inline int prepare_kprobe(struct kprobe *p)
-{
- return arch_prepare_kprobe(p);
-}
-
static inline int arm_kprobe_ftrace(struct kprobe *p)
{
return -ENODEV;
@@ -1118,6 +1104,15 @@ static inline int disarm_kprobe_ftrace(struct kprobe *p)
}
#endif
+static int prepare_kprobe(struct kprobe *p)
+{
+ /* Must ensure p->addr is really on ftrace */
+ if (kprobe_ftrace(p))
+ return arch_prepare_kprobe_ftrace(p);
+
+ return arch_prepare_kprobe(p);
+}
+
/* Arm a kprobe with text_mutex */
static int arm_kprobe(struct kprobe *kp)
{
--
2.30.2
next prev parent reply other threads:[~2021-06-09 10:51 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-09 10:50 [PATCH 0/5] kprobes: Bugfix and improvements Punit Agrawal
2021-06-09 10:50 ` [PATCH 1/5] kprobes: Do not use local variable when creating debugfs file Punit Agrawal
2021-06-09 14:35 ` Masami Hiramatsu
2021-06-10 23:31 ` Punit Agrawal
2021-06-09 10:50 ` [RFC PATCH 2/5] kprobes: Use helper to parse boolean input from userspace Punit Agrawal
2021-06-09 14:37 ` Masami Hiramatsu
2021-06-09 10:50 ` Punit Agrawal [this message]
2021-06-09 14:42 ` [RFC PATCH 3/5] kprobe: Simplify prepare_kprobe() by dropping redundant version Masami Hiramatsu
2021-06-09 10:50 ` [RFC PATCH 4/5] csky: ftrace: Drop duplicate implementation of arch_check_ftrace_location() Punit Agrawal
2021-06-09 12:33 ` Guo Ren
2021-06-09 14:29 ` Masami Hiramatsu
2021-06-09 15:47 ` Guo Ren
2021-06-10 0:07 ` Masami Hiramatsu
2021-06-09 10:50 ` [RFC PATCH 5/5] kprobes: Make arch_check_ftrace_location static Punit Agrawal
2021-06-10 0:37 ` Masami Hiramatsu
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