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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu: fix a mismatch between code and comment
  percpu: fix a memory leak in pcpu_extend_area_map()
  percpu: add __percpu notations to UP allocator
  percpu: handle __percpu notations in UP accessors
Linus Torvalds 15 years ago
parent
commit
ce7db282a3
4 changed files with 17 additions and 10 deletions
  1. 10 5
      include/asm-generic/percpu.h
  2. 1 1
      include/linux/percpu.h
  3. 4 2
      mm/percpu.c
  4. 2 2
      mm/percpu_up.c

+ 10 - 5
include/asm-generic/percpu.h

@@ -70,11 +70,16 @@ extern void setup_per_cpu_areas(void);
 
 #else /* ! SMP */
 
-#define per_cpu(var, cpu)			(*((void)(cpu), &(var)))
-#define __get_cpu_var(var)			(var)
-#define __raw_get_cpu_var(var)			(var)
-#define this_cpu_ptr(ptr) per_cpu_ptr(ptr, 0)
-#define __this_cpu_ptr(ptr) this_cpu_ptr(ptr)
+#define VERIFY_PERCPU_PTR(__p) ({			\
+	__verify_pcpu_ptr((__p));			\
+	(typeof(*(__p)) __kernel __force *)(__p);	\
+})
+
+#define per_cpu(var, cpu)	(*((void)(cpu), VERIFY_PERCPU_PTR(&(var))))
+#define __get_cpu_var(var)	(*VERIFY_PERCPU_PTR(&(var)))
+#define __raw_get_cpu_var(var)	(*VERIFY_PERCPU_PTR(&(var)))
+#define this_cpu_ptr(ptr)	per_cpu_ptr(ptr, 0)
+#define __this_cpu_ptr(ptr)	this_cpu_ptr(ptr)
 
 #endif	/* SMP */
 

+ 1 - 1
include/linux/percpu.h

@@ -149,7 +149,7 @@ extern void __init percpu_init_late(void);
 
 #else /* CONFIG_SMP */
 
-#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
+#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); VERIFY_PERCPU_PTR((ptr)); })
 
 /* can't distinguish from other static vars, always false */
 static inline bool is_kernel_percpu_address(unsigned long addr)

+ 4 - 2
mm/percpu.c

@@ -393,7 +393,9 @@ static int pcpu_extend_area_map(struct pcpu_chunk *chunk, int new_alloc)
 		goto out_unlock;
 
 	old_size = chunk->map_alloc * sizeof(chunk->map[0]);
-	memcpy(new, chunk->map, old_size);
+	old = chunk->map;
+
+	memcpy(new, old, old_size);
 
 	chunk->map_alloc = new_alloc;
 	chunk->map = new;
@@ -1162,7 +1164,7 @@ static struct pcpu_alloc_info * __init pcpu_build_alloc_info(
 		}
 
 		/*
-		 * Don't accept if wastage is over 25%.  The
+		 * Don't accept if wastage is over 1/3.  The
 		 * greater-than comparison ensures upa==1 always
 		 * passes the following check.
 		 */

+ 2 - 2
mm/percpu_up.c

@@ -14,13 +14,13 @@ void __percpu *__alloc_percpu(size_t size, size_t align)
 	 * percpu sections on SMP for which this path isn't used.
 	 */
 	WARN_ON_ONCE(align > SMP_CACHE_BYTES);
-	return kzalloc(size, GFP_KERNEL);
+	return (void __percpu __force *)kzalloc(size, GFP_KERNEL);
 }
 EXPORT_SYMBOL_GPL(__alloc_percpu);
 
 void free_percpu(void __percpu *p)
 {
-	kfree(p);
+	kfree(this_cpu_ptr(p));
 }
 EXPORT_SYMBOL_GPL(free_percpu);