From 7b83c6297d2fc7350997e86188df84c27fd59530 Mon Sep 17 00:00:00 2001
From: Heiko Carstens <heiko.carstens@de.ibm.com>
Date: Mon, 11 Sep 2017 11:24:23 +0200
Subject: [PATCH] s390/guarded storage: simplify task exit handling
Free data structures required for guarded storage from
arch_release_task_struct(). This allows to simplify the code a bit,
and also makes the semantics a bit easier: arch_release_task_struct()
is never called from the task that is being removed.
In addition this allows to get rid of exit_thread() in a later patch.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
arch/s390/include/asm/processor.h | 4 ++--
arch/s390/kernel/guarded_storage.c | 9 +++------
arch/s390/kernel/process.c | 3 +--
3 files changed, 6 insertions(+), 10 deletions(-)
diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h
index 4cc9bf53074be..58eaaccd3cf03 100644
--- a/arch/s390/include/asm/processor.h
+++ b/arch/s390/include/asm/processor.h
@@ -220,8 +220,8 @@ void show_cacheinfo(struct seq_file *m);
/* Free all resources held by a thread. */
static inline void release_thread(struct task_struct *tsk) { }
-/* Free guarded storage control block for current */
-void exit_thread_gs(void);
+/* Free guarded storage control block */
+void guarded_storage_release(struct task_struct *tsk);
unsigned long get_wchan(struct task_struct *p);
#define task_pt_regs(tsk) ((struct pt_regs *) \
diff --git a/arch/s390/kernel/guarded_storage.c b/arch/s390/kernel/guarded_storage.c
index 4920cf6ffa007..65b0eca2128c8 100644
--- a/arch/s390/kernel/guarded_storage.c
+++ b/arch/s390/kernel/guarded_storage.c
@@ -11,13 +11,10 @@
#include <asm/guarded_storage.h>
#include "entry.h"
-void exit_thread_gs(void)
+void guarded_storage_release(struct task_struct *tsk)
{
- preempt_disable();
- kfree(current->thread.gs_cb);
- kfree(current->thread.gs_bc_cb);
- current->thread.gs_cb = current->thread.gs_bc_cb = NULL;
- preempt_enable();
+ kfree(tsk->thread.gs_cb);
+ kfree(tsk->thread.gs_bc_cb);
}
static int gs_enable(void)
diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index a7c6c5e944c7c..0ecadd3491068 100644
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -48,8 +48,6 @@ extern void kernel_thread_starter(void);
*/
void exit_thread(struct task_struct *tsk)
{
- if (tsk == current)
- exit_thread_gs();
}
void flush_thread(void)
@@ -59,6 +57,7 @@ void flush_thread(void)
void arch_release_task_struct(struct task_struct *tsk)
{
runtime_instr_release(tsk);
+ guarded_storage_release(tsk);
}
int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
--
2.30.2