Merge "Revert "arm64: fpsimd: Enable FP(floating-point) settings for msm8996""

arch/arm64/Kconfig

@@ -513,37 +513,6 @@ config ARM64_64K_PAGES
 
 endchoice
 
-config MSM_APP_API
-	bool "API support to enable / disable app settings for MSM8996"
-	depends on ARCH_MSM8996 && (ENABLE_FP_SIMD_SETTINGS || MSM_APP_SETTINGS)
-	help
-	  Add API support to enable / disable the app settings to be used
-	  at runtime. These APIs are used to enable / disable app setting
-	  when specific aarch32 or aarch64 processes are running.
-
-	  If you are not sure what to do, select 'N' here.
-
-config ENABLE_FP_SIMD_SETTINGS
-	bool "Enable FP(Floating Point) Settings for Qualcomm MSM8996"
-	depends on ARCH_MSM8996
-	select MSM_APP_API
-	help
-	  Enable FP(Floating Point) and SIMD settings for the MSM8996 during
-	  the execution of the aarch32 processes and disable these settings
-	  when you switch to the aarch64 processes.
-
-	  If you are not sure what to do, select 'N' here.
-
-config MSM_APP_SETTINGS
-	bool "Support to enable / disable app settings for MSM8996"
-	depends on ARCH_MSM8996
-	select MSM_APP_API
-	help
-	  Expose an interface used by the userspace at runtime to
-	  enable / disable the app specific settings.
-
-	  If you are not sure what to do, select 'N' here.
-
 choice
 	prompt "Virtual address space size"
 	default ARM64_VA_BITS_39 if ARM64_4K_PAGES

arch/arm64/configs/msm-perf_defconfig

@@ -44,8 +44,6 @@ CONFIG_ARCH_QCOM=y
 CONFIG_ARCH_MSM8996=y
 CONFIG_PCI=y
 CONFIG_PCI_MSM=y
-CONFIG_ENABLE_FP_SIMD_SETTINGS=y
-CONFIG_MSM_APP_SETTINGS=y
 CONFIG_SCHED_MC=y
 CONFIG_NR_CPUS=8
 CONFIG_PREEMPT=y

arch/arm64/configs/msm_defconfig

@@ -41,8 +41,6 @@ CONFIG_ARCH_QCOM=y
 CONFIG_ARCH_MSM8996=y
 CONFIG_PCI=y
 CONFIG_PCI_MSM=y
-CONFIG_ENABLE_FP_SIMD_SETTINGS=y
-CONFIG_MSM_APP_SETTINGS=y
 CONFIG_SCHED_MC=y
 CONFIG_NR_CPUS=8
 CONFIG_PREEMPT=y

arch/arm64/include/asm/app_api.h

@@ -1,42 +0,0 @@
-/* Copyright (c) 2016, The Linux Foundation. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 and
- * only version 2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- */
-
-#ifndef __ASM_APP_API_H
-#define __ASM_APP_API_H
-
-#include <linux/types.h>
-#include <linux/sched.h>
-#include <linux/fs.h>
-
-#define APP_SETTING_BIT		30
-#define MAX_ENTRIES		10
-
-/*
- * APIs to set / clear the app setting bits
- * in the register.
- */
-#ifdef CONFIG_MSM_APP_API
-extern void set_app_setting_bit(uint32_t bit);
-extern void clear_app_setting_bit(uint32_t bit);
-#else
-static inline void set_app_setting_bit(uint32_t bit) {}
-static inline void clear_app_setting_bit(uint32_t bit) {}
-#endif
-
-#ifdef CONFIG_MSM_APP_SETTINGS
-extern void switch_app_setting_bit(struct task_struct *prev,
-				   struct task_struct *next);
-extern void apply_app_setting_bit(struct file *file);
-extern bool use_app_setting;
-#endif
-
-#endif

arch/arm64/include/asm/elf.h

@@ -23,7 +23,6 @@
  */
 #include <asm/ptrace.h>
 #include <asm/user.h>
-#include <asm/fpsimd.h>
 
 typedef unsigned long elf_greg_t;
 
@@ -178,11 +177,7 @@ typedef compat_elf_greg_t		compat_elf_gregset_t[COMPAT_ELF_NGREG];
 					 ((x)->e_flags & EF_ARM_EABI_MASK))
 
 #define compat_start_thread		compat_start_thread
-#define COMPAT_SET_PERSONALITY(ex)					\
+#define COMPAT_SET_PERSONALITY(ex)	set_thread_flag(TIF_32BIT);
-do {									\
-	set_thread_flag(TIF_32BIT);					\
-} while (0)
-
 #define COMPAT_ARCH_DLINFO
 extern int aarch32_setup_vectors_page(struct linux_binprm *bprm,
 				      int uses_interp);

arch/arm64/include/asm/fpsimd.h

@@ -81,14 +81,6 @@ extern void fpsimd_save_partial_state(struct fpsimd_partial_state *state,
 				      u32 num_regs);
 extern void fpsimd_load_partial_state(struct fpsimd_partial_state *state);
 
-#ifdef CONFIG_ENABLE_FP_SIMD_SETTINGS
-extern void fpsimd_disable_trap(void);
-extern void fpsimd_enable_trap(void);
-#else
-static inline void fpsimd_disable_trap(void) {}
-static inline void fpsimd_enable_trap(void) {}
-#endif
-
 #endif
 
 #endif

arch/arm64/kernel/Makefile

@@ -43,8 +43,6 @@ arm64-obj-$(CONFIG_EFI)			+= efi.o efi-entry.stub.o
 arm64-obj-$(CONFIG_PCI)			+= pci.o
 arm64-obj-$(CONFIG_ARMV8_DEPRECATED)	+= armv8_deprecated.o
 arm64-obj-$(CONFIG_ACPI)		+= acpi.o
-arm64-obj-$(CONFIG_MSM_APP_API)		+= app_api.o
-arm64-obj-$(CONFIG_MSM_APP_SETTINGS)	+= app_setting.o
 
 obj-y					+= $(arm64-obj-y) vdso/
 obj-m					+= $(arm64-obj-m)

arch/arm64/kernel/app_api.c

@@ -1,75 +0,0 @@
-/* Copyright (c) 2016, The Linux Foundation. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 and
- * only version 2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- */
-
-#include <linux/bitops.h>
-#include <linux/spinlock.h>
-#include <linux/cpu.h>
-#include <linux/export.h>
-
-#include <asm/app_api.h>
-
-static spinlock_t spinlock;
-static DEFINE_PER_CPU(int, app_config_applied);
-static unsigned long app_config_set[NR_CPUS];
-static unsigned long app_config_clear[NR_CPUS];
-
-void set_app_setting_bit(uint32_t bit)
-{
-	unsigned long flags;
-	uint64_t reg;
-	int cpu;
-
-	spin_lock_irqsave(&spinlock, flags);
-	asm volatile("mrs %0, S3_1_C15_C15_0" : "=r" (reg));
-	reg = reg | BIT(bit);
-	isb();
-	asm volatile("msr S3_1_C15_C15_0, %0" : : "r" (reg));
-	isb();
-	if (bit == APP_SETTING_BIT) {
-		cpu = raw_smp_processor_id();
-		app_config_set[cpu]++;
-
-		this_cpu_write(app_config_applied, 1);
-	}
-	spin_unlock_irqrestore(&spinlock, flags);
-
-}
-EXPORT_SYMBOL(set_app_setting_bit);
-
-void clear_app_setting_bit(uint32_t bit)
-{
-	unsigned long flags;
-	uint64_t reg;
-	int cpu;
-
-	spin_lock_irqsave(&spinlock, flags);
-	asm volatile("mrs %0, S3_1_C15_C15_0" : "=r" (reg));
-	reg = reg & ~BIT(bit);
-	isb();
-	asm volatile("msr S3_1_C15_C15_0, %0" : : "r" (reg));
-	isb();
-	if (bit == APP_SETTING_BIT) {
-		cpu = raw_smp_processor_id();
-		app_config_clear[cpu]++;
-
-		this_cpu_write(app_config_applied, 0);
-	}
-	spin_unlock_irqrestore(&spinlock, flags);
-}
-EXPORT_SYMBOL(clear_app_setting_bit);
-
-static int __init init_app_api(void)
-{
-	spin_lock_init(&spinlock);
-	return 0;
-}
-early_initcall(init_app_api);

arch/arm64/kernel/app_setting.c

@@ -1,120 +0,0 @@
-/* Copyright (c) 2016, The Linux Foundation. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 and
- * only version 2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- */
-
-#include <linux/module.h>
-#include <linux/cpu.h>
-#include <linux/slab.h>
-#include <linux/notifier.h>
-
-#include <asm/app_api.h>
-
-#define MAX_LEN		100
-
-static char *lib_names[MAX_ENTRIES];
-static unsigned int count;
-static struct mutex mutex;
-
-static char lib_str[MAX_LEN] = "";
-static struct kparam_string kps = {
-	.string			= lib_str,
-	.maxlen			= MAX_LEN,
-};
-static int set_name(const char *str, struct kernel_param *kp);
-module_param_call(lib_name, set_name, param_get_string, &kps, S_IWUSR);
-
-bool use_app_setting = true;
-module_param(use_app_setting, bool, 0644);
-MODULE_PARM_DESC(use_app_setting, "control use of app specific settings");
-
-static int set_name(const char *str, struct kernel_param *kp)
-{
-	int len = strlen(str);
-	char *name;
-
-	if (len >= MAX_LEN) {
-		pr_err("app_setting: name string too long\n");
-		return -ENOSPC;
-	}
-
-	/*
-	 * echo adds '\n' which we need to chop off later
-	 */
-	name = kzalloc(len + 1, GFP_KERNEL);
-	if (!name)
-		return -ENOMEM;
-
-	strlcpy(name, str, len + 1);
-
-	if (name[len - 1] == '\n')
-		name[len - 1] = '\0';
-
-	mutex_lock(&mutex);
-	if (count < MAX_ENTRIES) {
-		lib_names[count] = name;
-		/*
-		 * mb to ensure that the new lib_names entry is present
-		 * before updating the view presented by get_lib_names
-		 */
-		mb();
-		count++;
-	} else {
-		pr_err("app_setting: set name failed. Max entries reached\n");
-		kfree(name);
-		mutex_unlock(&mutex);
-		return -EPERM;
-	}
-	mutex_unlock(&mutex);
-
-	return 0;
-}
-
-void switch_app_setting_bit(struct task_struct *prev, struct task_struct *next)
-{
-	if (prev->mm && unlikely(prev->mm->app_setting))
-		clear_app_setting_bit(APP_SETTING_BIT);
-
-	if (next->mm && unlikely(next->mm->app_setting))
-		set_app_setting_bit(APP_SETTING_BIT);
-}
-EXPORT_SYMBOL(switch_app_setting_bit);
-
-void apply_app_setting_bit(struct file *file)
-{
-	bool found = false;
-	int i;
-
-	if (file && file->f_path.dentry) {
-		const char *name = file->f_path.dentry->d_name.name;
-
-		for (i = 0; i < count; i++) {
-			if (unlikely(!strcmp(name, lib_names[i]))) {
-				found = true;
-				break;
-			}
-		}
-		if (found) {
-			preempt_disable();
-			set_app_setting_bit(APP_SETTING_BIT);
-			/* This will take care of child processes as well */
-			current->mm->app_setting = 1;
-			preempt_enable();
-		}
-	}
-}
-EXPORT_SYMBOL(apply_app_setting_bit);
-
-static int __init app_setting_init(void)
-{
-	mutex_init(&mutex);
-	return 0;
-}
-module_init(app_setting_init);

arch/arm64/kernel/entry-fpsimd.S

@@ -64,20 +64,4 @@ ENTRY(fpsimd_load_partial_state)
 	ret
 ENDPROC(fpsimd_load_partial_state)
 
-#ifdef CONFIG_ENABLE_FP_SIMD_SETTINGS
-ENTRY(fpsimd_enable_trap)
-	mrs x0, cpacr_el1
-	bic x0, x0, #(3 << 20)
-	orr x0, x0, #(1 << 20)
-	msr cpacr_el1, x0
-	ret
-ENDPROC(fpsimd_enable_trap)
-ENTRY(fpsimd_disable_trap)
-	mrs x0, cpacr_el1
-	orr x0, x0, #(3 << 20)
-	msr cpacr_el1, x0
-	ret
-ENDPROC(fpsimd_disable_trap)
-#endif
-
 #endif

arch/arm64/kernel/entry.S

@@ -427,7 +427,7 @@ el0_sync_compat:
 	cmp	x24, #ESR_ELx_EC_IABT_LOW	// instruction abort in EL0
 	b.eq	el0_ia
 	cmp	x24, #ESR_ELx_EC_FP_ASIMD	// FP/ASIMD access
-	b.eq	el0_fpsimd_acc_compat
+	b.eq	el0_fpsimd_acc
 	cmp	x24, #ESR_ELx_EC_FP_EXC32	// FP/ASIMD exception
 	b.eq	el0_fpsimd_exc
 	cmp	x24, #ESR_ELx_EC_PC_ALIGN	// pc alignment exception
@@ -498,17 +498,6 @@ el0_fpsimd_acc:
 	mov	x1, sp
 	bl	do_fpsimd_acc
 	b	ret_to_user
-el0_fpsimd_acc_compat:
-	/*
-	 * Floating Point or Advanced SIMD access
-	 */
-	enable_dbg
-	ct_user_exit
-	mov	x0, x25
-	mov	x1, sp
-	bl	do_fpsimd_acc_compat
-	b	ret_to_user
-
 el0_fpsimd_exc:
 	/*
 	 * Floating Point or Advanced SIMD exception

arch/arm64/kernel/fpsimd.c

@@ -20,7 +20,6 @@
 #include <linux/cpu.h>
 #include <linux/cpu_pm.h>
 #include <linux/kernel.h>
-#include <linux/module.h>
 #include <linux/init.h>
 #include <linux/sched.h>
 #include <linux/signal.h>
@@ -28,7 +27,6 @@
 
 #include <asm/fpsimd.h>
 #include <asm/cputype.h>
-#include <asm/app_api.h>
 
 #define FPEXC_IOF	(1 << 0)
 #define FPEXC_DZF	(1 << 1)
@@ -37,8 +35,6 @@
 #define FPEXC_IXF	(1 << 4)
 #define FPEXC_IDF	(1 << 7)
 
-#define FP_SIMD_BIT	31
-
 /*
  * In order to reduce the number of times the FPSIMD state is needlessly saved
  * and restored, we need to keep track of two things:
@@ -92,42 +88,14 @@
  *   whatever is in the FPSIMD registers is not saved to memory, but discarded.
  */
 static DEFINE_PER_CPU(struct fpsimd_state *, fpsimd_last_state);
-static DEFINE_PER_CPU(int, fpsimd_stg_enable);
-
-static int fpsimd_settings = 0x1; /* default = 0x1 */
-module_param(fpsimd_settings, int, 0644);
-
-void fpsimd_settings_enable(void)
-{
-	set_app_setting_bit(FP_SIMD_BIT);
-}
-
-void fpsimd_settings_disable(void)
-{
-	clear_app_setting_bit(FP_SIMD_BIT);
-}
 
 /*
  * Trapped FP/ASIMD access.
  */
 void do_fpsimd_acc(unsigned int esr, struct pt_regs *regs)
 {
-	if (!fpsimd_settings)
+	/* TODO: implement lazy context saving/restoring */
-		return;
+	WARN_ON(1);
-
-	fpsimd_disable_trap();
-	fpsimd_settings_disable();
-	this_cpu_write(fpsimd_stg_enable, 0);
-}
-
-void do_fpsimd_acc_compat(unsigned int esr, struct pt_regs *regs)
-{
-	if (!fpsimd_settings)
-		return;
-
-	fpsimd_disable_trap();
-	fpsimd_settings_enable();
-	this_cpu_write(fpsimd_stg_enable, 1);
 }
 
 /*
@@ -167,11 +135,6 @@ void fpsimd_thread_switch(struct task_struct *next)
 	if (current->mm && !test_thread_flag(TIF_FOREIGN_FPSTATE))
 		fpsimd_save_state(&current->thread.fpsimd_state);
 
-	if (fpsimd_settings && __this_cpu_read(fpsimd_stg_enable)) {
-		fpsimd_settings_disable();
-		this_cpu_write(fpsimd_stg_enable, 0);
-	}
-
 	if (next->mm) {
 		/*
 		 * If we are switching to a task whose most recent userland
@@ -189,14 +152,6 @@ void fpsimd_thread_switch(struct task_struct *next)
 		else
 			set_ti_thread_flag(task_thread_info(next),
 					   TIF_FOREIGN_FPSTATE);
-
-		if (!fpsimd_settings)
-			return;
-
-		if (test_ti_thread_flag(task_thread_info(next), TIF_32BIT))
-			fpsimd_enable_trap();
-		else
-			fpsimd_disable_trap();
 	}
 }
 

include/linux/mm_types.h

@@ -522,10 +522,6 @@ struct mm_struct {
 #ifdef CONFIG_HUGETLB_PAGE
 	atomic_long_t hugetlb_usage;
 #endif
-#ifdef CONFIG_MSM_APP_SETTINGS
-	int app_setting;
-#endif
-
 };
 
 static inline void mm_init_cpumask(struct mm_struct *mm)

kernel/sched/core.c

@@ -85,9 +85,6 @@
 #ifdef CONFIG_PARAVIRT
 #include <asm/paravirt.h>
 #endif
-#ifdef CONFIG_MSM_APP_SETTINGS
-#include <asm/app_api.h>
-#endif
 
 #include "sched.h"
 #include "../workqueue_internal.h"
@@ -5895,11 +5892,6 @@ prepare_task_switch(struct rq *rq, struct task_struct *prev,
 	fire_sched_out_preempt_notifiers(prev, next);
 	prepare_lock_switch(rq, next);
 	prepare_arch_switch(next);
-
-#ifdef CONFIG_MSM_APP_SETTINGS
-	if (use_app_setting)
-		switch_app_setting_bit(prev, next);
-#endif
 }
 
 /**

mm/mmap.c

@@ -48,10 +48,6 @@
 #include <asm/tlb.h>
 #include <asm/mmu_context.h>
 
-#ifdef CONFIG_MSM_APP_SETTINGS
-#include <asm/app_api.h>
-#endif
-
 #include "internal.h"
 
 #ifndef arch_mmap_check
@@ -1301,11 +1297,6 @@ unsigned long do_mmap(struct file *file, unsigned long addr,
 	if (!len)
 		return -EINVAL;
 
-#ifdef CONFIG_MSM_APP_SETTINGS
-	if (use_app_setting)
-		apply_app_setting_bit(file);
-#endif
-
 	/*
 	 * Does the application expect PROT_READ to imply PROT_EXEC?
 	 *