x86: Clean up various simple wrapper functions

Remove unneeded variables and assignments.

While we are here, let's fix the following as well:

  - Remove unnecessary parentheses
  - Remove unnecessary unsigned-suffix 'U' from constant values
  - Reword the comment in set_apic_id() (suggested by Thomas Gleixner)

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andrew Banman <abanman@sgi.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Daniel J Blueman <daniel@numascale.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Mike Travis <travis@sgi.com>
Cc: Nathan Zimmer <nzimmer@sgi.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steffen Persvold <sp@numascale.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Wei Jiangang <weijg.fnst@cn.fujitsu.com>
Link: http://lkml.kernel.org/r/1473573502-27954-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/kernel/apic/apic_flat_64.c

@@ -116,27 +116,17 @@ static void flat_send_IPI_all(int vector)
 
 static unsigned int flat_get_apic_id(unsigned long x)
 {
-	unsigned int id;
-
-	id = (((x)>>24) & 0xFFu);
-
-	return id;
+	return (x >> 24) & 0xFF;
 }
 
 static unsigned long set_apic_id(unsigned int id)
 {
-	unsigned long x;
-
-	x = ((id & 0xFFu)<<24);
-	return x;
+	return (id & 0xFF) << 24;
 }
 
 static unsigned int read_xapic_id(void)
 {
-	unsigned int id;
-
-	id = flat_get_apic_id(apic_read(APIC_ID));
-	return id;
+	return flat_get_apic_id(apic_read(APIC_ID));
 }
 
 static int flat_apic_id_registered(void)

arch/x86/kernel/apic/apic_numachip.c

@@ -40,10 +40,7 @@ static unsigned int numachip1_get_apic_id(unsigned long x)
 
 static unsigned long numachip1_set_apic_id(unsigned int id)
 {
-	unsigned long x;
-
-	x = ((id & 0xffU) << 24);
-	return x;
+	return (id & 0xff) << 24;
 }
 
 static unsigned int numachip2_get_apic_id(unsigned long x)

arch/x86/kernel/apic/x2apic_uv_x.c

@@ -533,11 +533,8 @@ static unsigned int x2apic_get_apic_id(unsigned long x)
 
 static unsigned long set_apic_id(unsigned int id)
 {
-	unsigned long x;
-
-	/* maskout x2apic_extra_bits ? */
-	x = id;
-	return x;
+	/* CHECKME: Do we need to mask out the xapic extra bits? */
+	return id;
 }
 
 static unsigned int uv_read_apic_id(void)

arch/x86/mm/pat_rbtree.c

@@ -254,9 +254,7 @@ struct memtype *rbt_memtype_erase(u64 start, u64 end)
 
 struct memtype *rbt_memtype_lookup(u64 addr)
 {
-	struct memtype *data;
-	data = memtype_rb_lowest_match(&memtype_rbroot, addr, addr + PAGE_SIZE);
-	return data;
+	return memtype_rb_lowest_match(&memtype_rbroot, addr, addr + PAGE_SIZE);
 }
 
 #if defined(CONFIG_DEBUG_FS)

arch/x86/platform/uv/bios_uv.c

@@ -149,11 +149,8 @@ EXPORT_SYMBOL_GPL(uv_bios_change_memprotect);
 s64
 uv_bios_reserved_page_pa(u64 buf, u64 *cookie, u64 *addr, u64 *len)
 {
-	s64 ret;
-
-	ret = uv_bios_call_irqsave(UV_BIOS_GET_PARTITION_ADDR, (u64)cookie,
-					(u64)addr, buf, (u64)len, 0);
-	return ret;
+	return uv_bios_call_irqsave(UV_BIOS_GET_PARTITION_ADDR, (u64)cookie,
+				    (u64)addr, buf, (u64)len, 0);
 }
 EXPORT_SYMBOL_GPL(uv_bios_reserved_page_pa);
 

arch/x86/platform/uv/tlb_uv.c

@@ -580,11 +580,7 @@ static int uv1_wait_completion(struct bau_desc *bau_desc,
  */
 static unsigned long uv2_3_read_status(unsigned long offset, int rshft, int desc)
 {
-	unsigned long descriptor_status;
-
-	descriptor_status =
-		((read_lmmr(offset) >> rshft) & UV_ACT_STATUS_MASK) << 1;
-	return descriptor_status;
+	return ((read_lmmr(offset) >> rshft) & UV_ACT_STATUS_MASK) << 1;
 }
 
 /*