Commit bc1a298f authored by Chris Metcalf's avatar Chris Metcalf
Browse files

tile: support CONFIG_PREEMPT 



This change adds support for CONFIG_PREEMPT (full kernel preemption).
In addition to the core support, this change includes a number
of places where we fix up uses of smp_processor_id() and per-cpu
variables.  I also eliminate the PAGE_HOME_HERE and PAGE_HOME_UNKNOWN
values for page homing, as it turns out they weren't being used.

Signed-off-by: default avatarChris Metcalf <cmetcalf@tilera.com>
parent 1182b69c

arch/tile/Kconfig

+2 −0
Original line number Diff line number Diff line
@@ -301,6 +301,8 @@ config PAGE_OFFSET 


source "mm/Kconfig"



source "kernel/Kconfig.preempt"



config CMDLINE_BOOL

	bool "Built-in kernel command line"

	default n

arch/tile/include/asm/homecache.h

+0 −8
Original line number Diff line number Diff line
@@ -44,16 +44,8 @@ struct zone; 
 */

#define PAGE_HOME_INCOHERENT -3



#if CHIP_HAS_CBOX_HOME_MAP()

/* Home for the page is distributed via hash-for-home. */

#define PAGE_HOME_HASH -4

#endif



/* Homing is unknown or unspecified.  Not valid for page_home(). */

#define PAGE_HOME_UNKNOWN -5



/* Home on the current cpu.  Not valid for page_home(). */

#define PAGE_HOME_HERE -6



/* Support wrapper to use instead of explicit hv_flush_remote(). */

extern void flush_remote(unsigned long cache_pfn, unsigned long cache_length,

arch/tile/include/asm/irqflags.h

+18 −3
Original line number Diff line number Diff line
@@ -124,6 +124,12 @@ 
DECLARE_PER_CPU(unsigned long long, interrupts_enabled_mask);

#define INITIAL_INTERRUPTS_ENABLED (1ULL << INT_MEM_ERROR)



#ifdef CONFIG_DEBUG_PREEMPT

/* Due to inclusion issues, we can't rely on <linux/smp.h> here. */

extern unsigned int debug_smp_processor_id(void);

# define smp_processor_id() debug_smp_processor_id()

#endif



/* Disable interrupts. */

#define arch_local_irq_disable() \

	interrupt_mask_set_mask(LINUX_MASKABLE_INTERRUPTS)
@@ -132,9 +138,18 @@ DECLARE_PER_CPU(unsigned long long, interrupts_enabled_mask); 
#define arch_local_irq_disable_all() \

	interrupt_mask_set_mask(-1ULL)



/*

 * Read the set of maskable interrupts.

 * We avoid the preemption warning here via __this_cpu_ptr since even

 * if irqs are already enabled, it's harmless to read the wrong cpu's

 * enabled mask.

 */

#define arch_local_irqs_enabled() \

	(*__this_cpu_ptr(&interrupts_enabled_mask))



/* Re-enable all maskable interrupts. */

#define arch_local_irq_enable() \

	interrupt_mask_reset_mask(__get_cpu_var(interrupts_enabled_mask))

	interrupt_mask_reset_mask(arch_local_irqs_enabled())



/* Disable or enable interrupts based on flag argument. */

#define arch_local_irq_restore(disabled) do { \
@@ -161,7 +176,7 @@ DECLARE_PER_CPU(unsigned long long, interrupts_enabled_mask); 


/* Prevent the given interrupt from being enabled next time we enable irqs. */

#define arch_local_irq_mask(interrupt) \

	(__get_cpu_var(interrupts_enabled_mask) &= ~(1ULL << (interrupt)))

	this_cpu_and(interrupts_enabled_mask, ~(1ULL << (interrupt)))



/* Prevent the given interrupt from being enabled immediately. */

#define arch_local_irq_mask_now(interrupt) do { \
@@ -171,7 +186,7 @@ DECLARE_PER_CPU(unsigned long long, interrupts_enabled_mask); 


/* Allow the given interrupt to be enabled next time we enable irqs. */

#define arch_local_irq_unmask(interrupt) \

	(__get_cpu_var(interrupts_enabled_mask) |= (1ULL << (interrupt)))

	this_cpu_or(interrupts_enabled_mask, (1ULL << (interrupt)))



/* Allow the given interrupt to be enabled immediately, if !irqs_disabled. */

#define arch_local_irq_unmask_now(interrupt) do { \

arch/tile/kernel/asm-offsets.c

+2 −0
Original line number Diff line number Diff line
@@ -58,6 +58,8 @@ void foo(void) 
	       offsetof(struct thread_info, status));

	DEFINE(THREAD_INFO_HOMECACHE_CPU_OFFSET,

	       offsetof(struct thread_info, homecache_cpu));

	DEFINE(THREAD_INFO_PREEMPT_COUNT_OFFSET,

	       offsetof(struct thread_info, preempt_count));

	DEFINE(THREAD_INFO_STEP_STATE_OFFSET,

	       offsetof(struct thread_info, step_state));

#ifdef __tilegx__

arch/tile/kernel/hardwall.c

+9 −9
Original line number Diff line number Diff line
@@ -272,9 +272,9 @@ static void hardwall_setup_func(void *info) 
	struct hardwall_info *r = info;

	struct hardwall_type *hwt = r->type;



	int cpu = smp_processor_id();

	int x = cpu % smp_width;

	int y = cpu / smp_width;

	int cpu = smp_processor_id();  /* on_each_cpu disables preemption */

	int x = cpu_x(cpu);

	int y = cpu_y(cpu);

	int bits = 0;

	if (x == r->ulhc_x)

		bits |= W_PROTECT;
@@ -317,6 +317,7 @@ static void hardwall_protect_rectangle(struct hardwall_info *r) 
	on_each_cpu_mask(&rect_cpus, hardwall_setup_func, r, 1);

}



/* Entered from INT_xDN_FIREWALL interrupt vector with irqs disabled. */

void __kprobes do_hardwall_trap(struct pt_regs* regs, int fault_num)

{

	struct hardwall_info *rect;
@@ -325,7 +326,6 @@ void __kprobes do_hardwall_trap(struct pt_regs* regs, int fault_num) 
	struct siginfo info;

	int cpu = smp_processor_id();

	int found_processes;

	unsigned long flags;

	struct pt_regs *old_regs = set_irq_regs(regs);



	irq_enter();
@@ -346,7 +346,7 @@ void __kprobes do_hardwall_trap(struct pt_regs* regs, int fault_num) 
	BUG_ON(hwt->disabled);



	/* This tile trapped a network access; find the rectangle. */

	spin_lock_irqsave(&hwt->lock, flags);

	spin_lock(&hwt->lock);

	list_for_each_entry(rect, &hwt->list, list) {

		if (cpumask_test_cpu(cpu, &rect->cpumask))

			break;
@@ -401,7 +401,7 @@ void __kprobes do_hardwall_trap(struct pt_regs* regs, int fault_num) 
		pr_notice("hardwall: no associated processes!\n");



 done:

	spin_unlock_irqrestore(&hwt->lock, flags);

	spin_unlock(&hwt->lock);



	/*

	 * We have to disable firewall interrupts now, or else when we
@@ -661,7 +661,7 @@ static int hardwall_deactivate(struct hardwall_type *hwt, 
		return -EINVAL;



	printk(KERN_DEBUG "Pid %d (%s) deactivated for %s hardwall: cpu %d\n",

	       task->pid, task->comm, hwt->name, smp_processor_id());

	       task->pid, task->comm, hwt->name, raw_smp_processor_id());

	return 0;

}
@@ -803,8 +803,8 @@ static void reset_xdn_network_state(struct hardwall_type *hwt) 
	/* Reset UDN coordinates to their standard value */

	{

		unsigned int cpu = smp_processor_id();

		unsigned int x = cpu % smp_width;

		unsigned int y = cpu / smp_width;

		unsigned int x = cpu_x(cpu);

		unsigned int y = cpu_y(cpu);

		__insn_mtspr(SPR_UDN_TILE_COORD, (x << 18) | (y << 7));

	}

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