summaryrefslogtreecommitdiffstats
path: root/debian/patches-rt/0298-mm-zsmalloc-Convert-zsmalloc_handle.lock-to-spinlock.patch
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--debian/patches-rt/0298-mm-zsmalloc-Convert-zsmalloc_handle.lock-to-spinlock.patch82
1 files changed, 82 insertions, 0 deletions
diff --git a/debian/patches-rt/0298-mm-zsmalloc-Convert-zsmalloc_handle.lock-to-spinlock.patch b/debian/patches-rt/0298-mm-zsmalloc-Convert-zsmalloc_handle.lock-to-spinlock.patch
new file mode 100644
index 000000000..d26ff0ea0
--- /dev/null
+++ b/debian/patches-rt/0298-mm-zsmalloc-Convert-zsmalloc_handle.lock-to-spinlock.patch
@@ -0,0 +1,82 @@
+From b4a9c84408720dd6da0cdb52fc3e7070aef9c4fe Mon Sep 17 00:00:00 2001
+From: Mike Galbraith <efault@gmx.de>
+Date: Tue, 24 Aug 2021 13:08:14 +0200
+Subject: [PATCH 298/323] mm, zsmalloc: Convert zsmalloc_handle.lock to
+ spinlock_t
+Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.10/older/patches-5.10.204-rt100.tar.xz
+
+local_lock_t becoming a synonym of spinlock_t had consequences for the RT
+mods to zsmalloc, which were taking a mutex while holding a local_lock,
+inspiring a lockdep "BUG: Invalid wait context" gripe.
+
+Converting zsmalloc_handle.lock to a spinlock_t restored lockdep silence.
+
+Cc: stable-rt@vger.kernel.org
+Signed-off-by: Mike Galbraith <efault@gmx.de>
+Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
+---
+ mm/zsmalloc.c | 12 ++++++------
+ 1 file changed, 6 insertions(+), 6 deletions(-)
+
+diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
+index 7dad2ff3e778..16ce2b05df90 100644
+--- a/mm/zsmalloc.c
++++ b/mm/zsmalloc.c
+@@ -82,7 +82,7 @@
+
+ struct zsmalloc_handle {
+ unsigned long addr;
+- struct mutex lock;
++ spinlock_t lock;
+ };
+
+ #define ZS_HANDLE_ALLOC_SIZE (sizeof(struct zsmalloc_handle))
+@@ -370,7 +370,7 @@ static unsigned long cache_alloc_handle(struct zs_pool *pool, gfp_t gfp)
+ if (p) {
+ struct zsmalloc_handle *zh = p;
+
+- mutex_init(&zh->lock);
++ spin_lock_init(&zh->lock);
+ }
+ #endif
+ return (unsigned long)p;
+@@ -930,7 +930,7 @@ static inline int testpin_tag(unsigned long handle)
+ #ifdef CONFIG_PREEMPT_RT
+ struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+- return mutex_is_locked(&zh->lock);
++ return spin_is_locked(&zh->lock);
+ #else
+ return bit_spin_is_locked(HANDLE_PIN_BIT, (unsigned long *)handle);
+ #endif
+@@ -941,7 +941,7 @@ static inline int trypin_tag(unsigned long handle)
+ #ifdef CONFIG_PREEMPT_RT
+ struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+- return mutex_trylock(&zh->lock);
++ return spin_trylock(&zh->lock);
+ #else
+ return bit_spin_trylock(HANDLE_PIN_BIT, (unsigned long *)handle);
+ #endif
+@@ -952,7 +952,7 @@ static void pin_tag(unsigned long handle) __acquires(bitlock)
+ #ifdef CONFIG_PREEMPT_RT
+ struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+- return mutex_lock(&zh->lock);
++ return spin_lock(&zh->lock);
+ #else
+ bit_spin_lock(HANDLE_PIN_BIT, (unsigned long *)handle);
+ #endif
+@@ -963,7 +963,7 @@ static void unpin_tag(unsigned long handle) __releases(bitlock)
+ #ifdef CONFIG_PREEMPT_RT
+ struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+- return mutex_unlock(&zh->lock);
++ return spin_unlock(&zh->lock);
+ #else
+ bit_spin_unlock(HANDLE_PIN_BIT, (unsigned long *)handle);
+ #endif
+--
+2.43.0
+