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Date:   Tue, 3 Aug 2021 16:48:56 +0800
From:   Jisheng Zhang <Jisheng.Zhang@synaptics.com>
To:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>
Cc:     x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
        linux-kernel@vger.kernel.org
Subject: [PATCH] x86/process: directly use try_get_task_stack() return value
 in get_wchan
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try_get_task_stack() has already properly gets target task's stack,
no need to call task_stack_page() again.

Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
---
 arch/x86/kernel/process.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 1d9463e3096b..d4a6503b3878 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -950,12 +950,9 @@ unsigned long get_wchan(struct task_struct *p)
 	if (p == current || task_is_running(p))
 		return 0;
 
-	if (!try_get_task_stack(p))
-		return 0;
-
-	start = (unsigned long)task_stack_page(p);
+	start = (unsigned long)try_get_task_stack(p);
 	if (!start)
-		goto out;
+		return 0;
 
 	/*
 	 * Layout of the stack page:
-- 
2.32.0