diff --git a/include/asm-generic/percpu.h b/include/asm-generic/percpu.h
index 35e4a53b83e6..6432a7fade91 100644
--- a/include/asm-generic/percpu.h
+++ b/include/asm-generic/percpu.h
@@ -114,21 +114,21 @@ do {									\
 
 #define __this_cpu_generic_read_nopreempt(pcp)				\
 ({									\
-	typeof(pcp) __ret;						\
+	typeof(pcp) ___ret;						\
 	preempt_disable_notrace();					\
-	__ret = READ_ONCE(*raw_cpu_ptr(&(pcp)));			\
+	___ret = READ_ONCE(*raw_cpu_ptr(&(pcp)));			\
 	preempt_enable_notrace();					\
-	__ret;								\
+	___ret;								\
 })
 
 #define __this_cpu_generic_read_noirq(pcp)				\
 ({									\
-	typeof(pcp) __ret;						\
-	unsigned long __flags;						\
-	raw_local_irq_save(__flags);					\
-	__ret = raw_cpu_generic_read(pcp);				\
-	raw_local_irq_restore(__flags);					\
-	__ret;								\
+	typeof(pcp) ___ret;						\
+	unsigned long ___flags;						\
+	raw_local_irq_save(___flags);					\
+	___ret = raw_cpu_generic_read(pcp);				\
+	raw_local_irq_restore(___flags);				\
+	___ret;								\
 })
 
 #define this_cpu_generic_read(pcp)					\
diff --git a/mm/percpu.c b/mm/percpu.c
index 66a93f096394..ad7a37ee74ef 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -1315,8 +1315,8 @@ static struct pcpu_chunk * __init pcpu_alloc_first_chunk(unsigned long tmp_addr,
 	region_size = ALIGN(start_offset + map_size, lcm_align);
 
 	/* allocate chunk */
-	alloc_size = sizeof(struct pcpu_chunk) +
-		BITS_TO_LONGS(region_size >> PAGE_SHIFT) * sizeof(unsigned long);
+	alloc_size = struct_size(chunk, populated,
+				 BITS_TO_LONGS(region_size >> PAGE_SHIFT));
 	chunk = memblock_alloc(alloc_size, SMP_CACHE_BYTES);
 	if (!chunk)
 		panic("%s: Failed to allocate %zu bytes\n", __func__,
@@ -2521,8 +2521,8 @@ void __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
 	pcpu_unit_pages = ai->unit_size >> PAGE_SHIFT;
 	pcpu_unit_size = pcpu_unit_pages << PAGE_SHIFT;
 	pcpu_atom_size = ai->atom_size;
-	pcpu_chunk_struct_size = sizeof(struct pcpu_chunk) +
-		BITS_TO_LONGS(pcpu_unit_pages) * sizeof(unsigned long);
+	pcpu_chunk_struct_size = struct_size(chunk, populated,
+					     BITS_TO_LONGS(pcpu_unit_pages));
 
 	pcpu_stats_save_ai(ai);