[PATCH 1/1] uprobe: fix comment of uprobe_apply()

Depending on the argument 'add', uprobe_apply() may be registering or
unregistering a probe. The current comment misses the description of the
registration.

Signed-off-by: Zhen Lei <redacted>
---
 kernel/events/uprobes.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 73cc47708679f0c..c9de255e56e777f 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c

@@ -1201,8 +1201,8 @@ int uprobe_register_refctr(struct inode *inode, loff_t offset,
 EXPORT_SYMBOL_GPL(uprobe_register_refctr);
 
 /*
- * uprobe_apply - unregister an already registered probe.
- * @inode: the file in which the probe has to be removed.
+ * uprobe_apply - register a probe or unregister an already registered probe.
+ * @inode: the file in which the probe has to be placed or removed.
  * @offset: offset from the start of the file.
  * @uc: consumer which wants to add more or remove some breakpoints
  * @add: add or remove the breakpoints

-- 
2.34.1

On 08/20, Zhen Lei wrote:

Depending on the argument 'add', uprobe_apply() may be registering or
unregistering a probe.

...

 /*
- * uprobe_apply - unregister an already registered probe.
- * @inode: the file in which the probe has to be removed.
+ * uprobe_apply - register a probe or unregister an already registered probe.

Not really.

See the commit 3c83a9ad0295eb63bd ("uprobes: make uprobe_register() return struct uprobe *")
in tip/perf/core which changed this description

	* uprobe_apply - add or remove the breakpoints according to @uc->filter

still looks confusing, yes...

Oleg.

On 2024/8/20 22:30, Oleg Nesterov wrote:

On 08/20, Zhen Lei wrote:

quoted

Depending on the argument 'add', uprobe_apply() may be registering or
unregistering a probe.

...

quoted

 /*
- * uprobe_apply - unregister an already registered probe.
- * @inode: the file in which the probe has to be removed.
+ * uprobe_apply - register a probe or unregister an already registered probe.

Not really.

See the commit 3c83a9ad0295eb63bd ("uprobes: make uprobe_register() return struct uprobe *")
in tip/perf/core which changed this description

	* uprobe_apply - add or remove the breakpoints according to @uc->filter

still looks confusing, yes...

OK, I got it. I mistakenly thought the comment was based on register_for_each_vma.
It seems necessary to rename 'register_for_each_vma' to 'apply_for_each_vma',
or some other more appropriate name.

Oleg.


.

-- 
Regards,
  Zhen Lei