aboutsummaryrefslogtreecommitdiffstats
path: root/features/rt/mm-zsmalloc-copy-with-get_cpu_var-and-locking.patch
diff options
context:
space:
mode:
Diffstat (limited to 'features/rt/mm-zsmalloc-copy-with-get_cpu_var-and-locking.patch')
-rw-r--r--features/rt/mm-zsmalloc-copy-with-get_cpu_var-and-locking.patch211
1 files changed, 0 insertions, 211 deletions
diff --git a/features/rt/mm-zsmalloc-copy-with-get_cpu_var-and-locking.patch b/features/rt/mm-zsmalloc-copy-with-get_cpu_var-and-locking.patch
deleted file mode 100644
index 20da73a1..00000000
--- a/features/rt/mm-zsmalloc-copy-with-get_cpu_var-and-locking.patch
+++ /dev/null
@@ -1,211 +0,0 @@
-From 58041154aa39fc127b4c5d0f6179c606403ced5d Mon Sep 17 00:00:00 2001
-From: Mike Galbraith <umgwanakikbuti@gmail.com>
-Date: Tue, 22 Mar 2016 11:16:09 +0100
-Subject: [PATCH 116/191] mm/zsmalloc: copy with get_cpu_var() and locking
-
-get_cpu_var() disables preemption and triggers a might_sleep() splat later.
-This is replaced with get_locked_var().
-This bitspinlocks are replaced with a proper mutex which requires a slightly
-larger struct to allocate.
-
-Signed-off-by: Mike Galbraith <umgwanakikbuti@gmail.com>
-[bigeasy: replace the bitspin_lock() with a mutex, get_locked_var(). Mike then
-fixed the size magic]
-Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
----
- mm/zsmalloc.c | 85 +++++++++++++++++++++++++++++++++++++++++++++++----
- 1 file changed, 79 insertions(+), 6 deletions(-)
-
-diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
-index 30c358b72025..6177b736d018 100644
---- a/mm/zsmalloc.c
-+++ b/mm/zsmalloc.c
-@@ -57,6 +57,7 @@
- #include <linux/wait.h>
- #include <linux/pagemap.h>
- #include <linux/fs.h>
-+#include <linux/local_lock.h>
-
- #define ZSPAGE_MAGIC 0x58
-
-@@ -77,6 +78,20 @@
-
- #define ZS_HANDLE_SIZE (sizeof(unsigned long))
-
-+#ifdef CONFIG_PREEMPT_RT
-+
-+struct zsmalloc_handle {
-+ unsigned long addr;
-+ struct mutex lock;
-+};
-+
-+#define ZS_HANDLE_ALLOC_SIZE (sizeof(struct zsmalloc_handle))
-+
-+#else
-+
-+#define ZS_HANDLE_ALLOC_SIZE (sizeof(unsigned long))
-+#endif
-+
- /*
- * Object location (<PFN>, <obj_idx>) is encoded as
- * a single (unsigned long) handle value.
-@@ -293,6 +308,7 @@ struct zspage {
- };
-
- struct mapping_area {
-+ local_lock_t lock;
- char *vm_buf; /* copy buffer for objects that span pages */
- char *vm_addr; /* address of kmap_atomic()'ed pages */
- enum zs_mapmode vm_mm; /* mapping mode */
-@@ -322,7 +338,7 @@ static void SetZsPageMovable(struct zs_pool *pool, struct zspage *zspage) {}
-
- static int create_cache(struct zs_pool *pool)
- {
-- pool->handle_cachep = kmem_cache_create("zs_handle", ZS_HANDLE_SIZE,
-+ pool->handle_cachep = kmem_cache_create("zs_handle", ZS_HANDLE_ALLOC_SIZE,
- 0, 0, NULL);
- if (!pool->handle_cachep)
- return 1;
-@@ -346,9 +362,26 @@ static void destroy_cache(struct zs_pool *pool)
-
- static unsigned long cache_alloc_handle(struct zs_pool *pool, gfp_t gfp)
- {
-- return (unsigned long)kmem_cache_alloc(pool->handle_cachep,
-- gfp & ~(__GFP_HIGHMEM|__GFP_MOVABLE));
-+ void *p;
-+
-+ p = kmem_cache_alloc(pool->handle_cachep,
-+ gfp & ~(__GFP_HIGHMEM|__GFP_MOVABLE));
-+#ifdef CONFIG_PREEMPT_RT
-+ if (p) {
-+ struct zsmalloc_handle *zh = p;
-+
-+ mutex_init(&zh->lock);
-+ }
-+#endif
-+ return (unsigned long)p;
-+}
-+
-+#ifdef CONFIG_PREEMPT_RT
-+static struct zsmalloc_handle *zs_get_pure_handle(unsigned long handle)
-+{
-+ return (void *)(handle &~((1 << OBJ_TAG_BITS) - 1));
- }
-+#endif
-
- static void cache_free_handle(struct zs_pool *pool, unsigned long handle)
- {
-@@ -368,12 +401,18 @@ static void cache_free_zspage(struct zs_pool *pool, struct zspage *zspage)
-
- static void record_obj(unsigned long handle, unsigned long obj)
- {
-+#ifdef CONFIG_PREEMPT_RT
-+ struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
-+
-+ WRITE_ONCE(zh->addr, obj);
-+#else
- /*
- * lsb of @obj represents handle lock while other bits
- * represent object value the handle is pointing so
- * updating shouldn't do store tearing.
- */
- WRITE_ONCE(*(unsigned long *)handle, obj);
-+#endif
- }
-
- /* zpool driver */
-@@ -455,7 +494,10 @@ MODULE_ALIAS("zpool-zsmalloc");
- #endif /* CONFIG_ZPOOL */
-
- /* per-cpu VM mapping areas for zspage accesses that cross page boundaries */
--static DEFINE_PER_CPU(struct mapping_area, zs_map_area);
-+static DEFINE_PER_CPU(struct mapping_area, zs_map_area) = {
-+ /* XXX remove this and use a spin_lock_t in pin_tag() */
-+ .lock = INIT_LOCAL_LOCK(lock),
-+};
-
- static bool is_zspage_isolated(struct zspage *zspage)
- {
-@@ -862,7 +904,13 @@ static unsigned long location_to_obj(struct page *page, unsigned int obj_idx)
-
- static unsigned long handle_to_obj(unsigned long handle)
- {
-+#ifdef CONFIG_PREEMPT_RT
-+ struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
-+
-+ return zh->addr;
-+#else
- return *(unsigned long *)handle;
-+#endif
- }
-
- static unsigned long obj_to_head(struct page *page, void *obj)
-@@ -876,22 +924,46 @@ static unsigned long obj_to_head(struct page *page, void *obj)
-
- 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);
-+#else
- return bit_spin_is_locked(HANDLE_PIN_BIT, (unsigned long *)handle);
-+#endif
- }
-
- 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);
-+#else
- return bit_spin_trylock(HANDLE_PIN_BIT, (unsigned long *)handle);
-+#endif
- }
-
- 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);
-+#else
- bit_spin_lock(HANDLE_PIN_BIT, (unsigned long *)handle);
-+#endif
- }
-
- 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);
-+#else
- bit_spin_unlock(HANDLE_PIN_BIT, (unsigned long *)handle);
-+#endif
- }
-
- static void reset_page(struct page *page)
-@@ -1274,7 +1346,8 @@ void *zs_map_object(struct zs_pool *pool, unsigned long handle,
- class = pool->size_class[class_idx];
- off = (class->size * obj_idx) & ~PAGE_MASK;
-
-- area = &get_cpu_var(zs_map_area);
-+ local_lock(&zs_map_area.lock);
-+ area = this_cpu_ptr(&zs_map_area);
- area->vm_mm = mm;
- if (off + class->size <= PAGE_SIZE) {
- /* this object is contained entirely within a page */
-@@ -1328,7 +1401,7 @@ void zs_unmap_object(struct zs_pool *pool, unsigned long handle)
-
- __zs_unmap_object(area, pages, off, class->size);
- }
-- put_cpu_var(zs_map_area);
-+ local_unlock(&zs_map_area.lock);
-
- migrate_read_unlock(zspage);
- unpin_tag(handle);
---
-2.19.1
-
generated by cgit 1.2.3-korg (git 2.39.0) at 2024-05-06 10:19:54 +0000