From 281eaa8cb67c27e56da1e7fd6b55c6cd3e8c4638 Mon Sep 17 00:00:00 2001
From: Heiko Carstens <heiko.carstens@de.ibm.com>
Date: Wed, 13 Apr 2016 14:49:12 +0200
Subject: s390/cpuinfo: simplify locking and skip offline cpus early

Move the get_online_cpus() and put_online_cpus() to the start and stop
operation of the seqfile ops. This way there is no need to lock cpu
hotplug again and again for each single cpu.

This way we can also skip offline cpus early if we simply use
cpumask_next() within the next operation.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 arch/s390/kernel/processor.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

(limited to 'arch/s390/kernel/processor.c')

diff --git a/arch/s390/kernel/processor.c b/arch/s390/kernel/processor.c
index 647128d5b983..90a418d5c280 100644
--- a/arch/s390/kernel/processor.c
+++ b/arch/s390/kernel/processor.c
@@ -84,7 +84,6 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 		seq_puts(m, "\n");
 		show_cacheinfo(m);
 	}
-	get_online_cpus();
 	if (cpu_online(n)) {
 		struct cpuid *id = &per_cpu(cpu_id, n);
 		seq_printf(m, "processor %li: "
@@ -93,23 +92,31 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 			   "machine = %04X\n",
 			   n, id->version, id->ident, id->machine);
 	}
-	put_online_cpus();
 	return 0;
 }
 
+static inline void *c_update(loff_t *pos)
+{
+	if (*pos)
+		*pos = cpumask_next(*pos - 1, cpu_online_mask);
+	return *pos < nr_cpu_ids ? (void *)*pos + 1 : NULL;
+}
+
 static void *c_start(struct seq_file *m, loff_t *pos)
 {
-	return *pos < nr_cpu_ids ? (void *)((unsigned long) *pos + 1) : NULL;
+	get_online_cpus();
+	return c_update(pos);
 }
 
 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 {
 	++*pos;
-	return c_start(m, pos);
+	return c_update(pos);
 }
 
 static void c_stop(struct seq_file *m, void *v)
 {
+	put_online_cpus();
 }
 
 const struct seq_operations cpuinfo_op = {
-- 
cgit v1.3-8-gc7d7


From ca21872e43e82c2a5c2e056ee4aea40a921720b1 Mon Sep 17 00:00:00 2001
From: Heiko Carstens <heiko.carstens@de.ibm.com>
Date: Sat, 7 May 2016 12:15:34 +0200
Subject: s390: add missing include statements

arch_mmap_rnd, cpu_have_feature, and arch_randomize_brk are all
defined as globally visible variables.
However the files they are defined in do not include the header files
with the declaration. To avoid a possible mismatch add the missing
include statements so we have proper type checking in place.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 arch/s390/kernel/process.c   | 1 +
 arch/s390/kernel/processor.c | 1 +
 arch/s390/mm/mmap.c          | 1 +
 3 files changed, 3 insertions(+)

(limited to 'arch/s390/kernel/processor.c')

diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index adb346b70166..481d7a83efc6 100644
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -7,6 +7,7 @@
  *		 Denis Joseph Barrow,
  */
 
+#include <linux/elf-randomize.h>
 #include <linux/compiler.h>
 #include <linux/cpu.h>
 #include <linux/sched.h>
diff --git a/arch/s390/kernel/processor.c b/arch/s390/kernel/processor.c
index 90a418d5c280..de7451065c34 100644
--- a/arch/s390/kernel/processor.c
+++ b/arch/s390/kernel/processor.c
@@ -6,6 +6,7 @@
 #define KMSG_COMPONENT "cpu"
 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 
+#include <linux/cpufeature.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/seq_file.h>
diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c
index 45c4daa49930..f4e5286a1e3e 100644
--- a/arch/s390/mm/mmap.c
+++ b/arch/s390/mm/mmap.c
@@ -22,6 +22,7 @@
  * Started by Ingo Molnar <mingo@elte.hu>
  */
 
+#include <linux/elf-randomize.h>
 #include <linux/personality.h>
 #include <linux/mm.h>
 #include <linux/mman.h>
-- 
cgit v1.3-8-gc7d7