[RFC PATCH 03/11] MIPS: Remove unused task argument from prctl functions

From: Dave Martin
Date: Mon May 14 2018 - 13:18:19 EST


Some MIPS-specific prctl backends take a task argument that is
redundant, since the only thing ever passed is "current".

This patch gets rid of the redundant arguments.

No functional change.

Signed-off-by: Dave Martin <Dave.Martin@xxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: James Hogan <jhogan@xxxxxxxxxx>
---
arch/mips/include/asm/processor.h | 4 ++--
arch/mips/kernel/process.c | 23 +++++++++++------------
arch/mips/kernel/syscall.c | 1 +
kernel/sys.c | 8 ++++----
4 files changed, 18 insertions(+), 18 deletions(-)

diff --git a/arch/mips/include/asm/processor.h b/arch/mips/include/asm/processor.h
index af34afb..8f06608 100644
--- a/arch/mips/include/asm/processor.h
+++ b/arch/mips/include/asm/processor.h
@@ -420,7 +420,7 @@ extern int mips_get_process_fp_mode(struct task_struct *task);
extern int mips_set_process_fp_mode(struct task_struct *task,
unsigned int value);

-#define GET_FP_MODE(task) mips_get_process_fp_mode(task)
-#define SET_FP_MODE(task,value) mips_set_process_fp_mode(task, value)
+#define GET_FP_MODE() mips_get_process_fp_mode()
+#define SET_FP_MODE(value) mips_set_process_fp_mode(value)

#endif /* _ASM_PROCESSOR_H */
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index b9e9bf6..7db1989 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -679,13 +679,13 @@ void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
put_cpu();
}

-int mips_get_process_fp_mode(struct task_struct *task)
+int mips_get_process_fp_mode(void)
{
int value = 0;

- if (!test_tsk_thread_flag(task, TIF_32BIT_FPREGS))
+ if (!test_thread_flag(TIF_32BIT_FPREGS))
value |= PR_FP_MODE_FR;
- if (test_tsk_thread_flag(task, TIF_HYBRID_FPREGS))
+ if (test_thread_flag(TIF_HYBRID_FPREGS))
value |= PR_FP_MODE_FRE;

return value;
@@ -699,14 +699,14 @@ static void prepare_for_fp_mode_switch(void *info)
lose_fpu(1);
}

-int mips_set_process_fp_mode(struct task_struct *task, unsigned int value)
+int mips_set_process_fp_mode(unsigned int value)
{
const unsigned int known_bits = PR_FP_MODE_FR | PR_FP_MODE_FRE;
struct task_struct *t;
int max_users;

/* If nothing to change, return right away, successfully. */
- if (value == mips_get_process_fp_mode(task))
+ if (value == mips_get_process_fp_mode())
return 0;

/* Only accept a mode change if 64-bit FP enabled for o32. */
@@ -736,11 +736,10 @@ int mips_set_process_fp_mode(struct task_struct *task, unsigned int value)
preempt_disable();

/* Save FP & vector context, then disable FPU & MSA */
- if (task->signal == current->signal)
- lose_fpu(1);
+ lose_fpu(1);

/* Prevent any threads from obtaining live FP context */
- atomic_set(&task->mm->context.fp_mode_switching, 1);
+ atomic_set(&current->mm->context.fp_mode_switching, 1);
smp_mb__after_atomic();

/*
@@ -750,7 +749,7 @@ int mips_set_process_fp_mode(struct task_struct *task, unsigned int value)
*/
if (num_online_cpus() > 1) {
/* No need to send an IPI for the local CPU */
- max_users = (task->mm == current->mm) ? 1 : 0;
+ max_users = (current->mm == current->mm) ? 1 : 0;

if (atomic_read(&current->mm->mm_users) > max_users)
smp_call_function(prepare_for_fp_mode_switch,
@@ -761,7 +760,7 @@ int mips_set_process_fp_mode(struct task_struct *task, unsigned int value)
* There are now no threads of the process with live FP context, so it
* is safe to proceed with the FP mode switch.
*/
- for_each_thread(task, t) {
+ for_each_thread(current, t) {
/* Update desired FP register width */
if (value & PR_FP_MODE_FR) {
clear_tsk_thread_flag(t, TIF_32BIT_FPREGS);
@@ -778,10 +777,10 @@ int mips_set_process_fp_mode(struct task_struct *task, unsigned int value)
}

/* Allow threads to use FP again */
- atomic_set(&task->mm->context.fp_mode_switching, 0);
+ atomic_set(&current->mm->context.fp_mode_switching, 0);
preempt_enable();

- wake_up_var(&task->mm->context.fp_mode_switching);
+ wake_up_var(&current->mm->context.fp_mode_switching);

return 0;
}
diff --git a/arch/mips/kernel/syscall.c b/arch/mips/kernel/syscall.c
index 69c17b5..15f33f0 100644
--- a/arch/mips/kernel/syscall.c
+++ b/arch/mips/kernel/syscall.c
@@ -12,6 +12,7 @@
#include <linux/linkage.h>
#include <linux/fs.h>
#include <linux/smp.h>
+#include <linux/prctl.h>
#include <linux/ptrace.h>
#include <linux/string.h>
#include <linux/syscalls.h>
diff --git a/kernel/sys.c b/kernel/sys.c
index f917d78..520d2e8 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -108,10 +108,10 @@
# define MPX_DISABLE_MANAGEMENT() (-EINVAL)
#endif
#ifndef GET_FP_MODE
-# define GET_FP_MODE(a) (-EINVAL)
+# define GET_FP_MODE() (-EINVAL)
#endif
#ifndef SET_FP_MODE
-# define SET_FP_MODE(a,b) (-EINVAL)
+# define SET_FP_MODE(a) (-EINVAL)
#endif

/*
@@ -2433,10 +2433,10 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
error = MPX_DISABLE_MANAGEMENT();
break;
case PR_SET_FP_MODE:
- error = SET_FP_MODE(me, arg2);
+ error = SET_FP_MODE(arg2);
break;
case PR_GET_FP_MODE:
- error = GET_FP_MODE(me);
+ error = GET_FP_MODE();
break;
default:
error = prctl_arch(option, arg2, arg3, arg4, arg5);
--
2.1.4