[PATCH v10 3/4] mm: memory-failure: move memory_failure() return value documentation to function declaration

[Shuai Xue <xueshuai@linux.alibaba.com>]

Part of return value comments for memory_failure() were originally
documented at the call site. Move those comments to the function
declaration to improve code readability and to provide developers with
immediate access to function usage and return information.

Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
---
 arch/x86/kernel/cpu/mce/core.c | 9 +--------
 mm/memory-failure.c            | 9 ++++++---
 2 files changed, 7 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index 7b397370b4d6..43e542f06ad5 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -1324,17 +1324,10 @@ static void kill_me_maybe(struct callback_head *cb)
 		return;
 	}
 
-	/*
-	 * -EHWPOISON from memory_failure() means that it already sent SIGBUS
-	 * to the current process with the proper error info,
-	 * -EOPNOTSUPP means hwpoison_filter() filtered the error event,
-	 *
-	 * In both cases, no further processing is required.
-	 */
 	if (ret == -EHWPOISON || ret == -EOPNOTSUPP)
 		return;
 
-	pr_err("Memory error not recovered");
+	pr_err("Sending SIGBUS to current task due to memory error not recovered");
 	kill_me_now(cb);
 }
 
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 660c21859118..bd3dcafdfa4a 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -2164,9 +2164,12 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags,
  * Must run in process context (e.g. a work queue) with interrupts
  * enabled and no spinlocks held.
  *
- * Return: 0 for successfully handled the memory error,
- *         -EOPNOTSUPP for hwpoison_filter() filtered the error event,
- *         < 0(except -EOPNOTSUPP) on failure.
+ * Return values:
+ *   0             - success
+ *   -EOPNOTSUPP   - hwpoison_filter() filtered the error event.
+ *   -EHWPOISON    - sent SIGBUS to the current process with the proper
+ *                   error info by kill_accessing_process().
+ *   other negative values - failure
  */
 int memory_failure(unsigned long pfn, int flags)
 {
-- 
2.39.3