linux/debian/patches-rt/0248-drivers-zram-fix-zcomp_stream_get-smp_processor_id-u.patch

From a59a1afa0b2b3b350daaf85858889bcdeec01607 Mon Sep 17 00:00:00 2001
Message-Id: <a59a1afa0b2b3b350daaf85858889bcdeec01607.1601675152.git.zanussi@kernel.org>
In-Reply-To: <5b5a156f9808b1acf1205606e03da117214549ea.1601675151.git.zanussi@kernel.org>
References: <5b5a156f9808b1acf1205606e03da117214549ea.1601675151.git.zanussi@kernel.org>
From: Mike Galbraith <efault@gmx.de>
Date: Wed, 23 Aug 2017 11:57:29 +0200
Subject: [PATCH 248/333] drivers/zram: fix zcomp_stream_get()
 smp_processor_id() use in preemptible code
Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.148-rt64.tar.xz

Use get_local_ptr() instead this_cpu_ptr() to avoid a warning regarding
smp_processor_id() in preemptible code.
raw_cpu_ptr() would be fine, too because the per-CPU data structure is
protected with a spin lock so it does not matter much if we take the
other one.

Cc: stable-rt@vger.kernel.org
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 drivers/block/zram/zcomp.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/block/zram/zcomp.c b/drivers/block/zram/zcomp.c
index dd65a27ae2cc..eece02262000 100644
--- a/drivers/block/zram/zcomp.c
+++ b/drivers/block/zram/zcomp.c
@@ -118,7 +118,7 @@ struct zcomp_strm *zcomp_stream_get(struct zcomp *comp)
 {
 	struct zcomp_strm *zstrm;
 
-	zstrm = *this_cpu_ptr(comp->stream);
+	zstrm = *get_local_ptr(comp->stream);
 	spin_lock(&zstrm->zcomp_lock);
 	return zstrm;
 }
@@ -129,6 +129,7 @@ void zcomp_stream_put(struct zcomp *comp)
 
 	zstrm = *this_cpu_ptr(comp->stream);
 	spin_unlock(&zstrm->zcomp_lock);
+	put_local_ptr(zstrm);
 }
 
 int zcomp_compress(struct zcomp_strm *zstrm,
-- 
2.17.1