Commit f133ecca authored by Chris Metcalf's avatar Chris Metcalf
Browse files

arch/tile: more /proc and /sys file support 



This change introduces a few of the less controversial /proc and
/proc/sys interfaces for tile, along with sysfs attributes for
various things that were originally proposed as /proc/tile files.
It also adjusts the "hardwall" proc API.

Arnd Bergmann reviewed the initial arch/tile submission, which
included a complete set of all the /proc/tile and /proc/sys/tile
knobs that we had added in a somewhat ad hoc way during initial
development, and provided feedback on where most of them should go.

One knob turned out to be similar enough to the existing
/proc/sys/debug/exception-trace that it was re-implemented to use
that model instead.

Another knob was /proc/tile/grid, which reported the "grid" dimensions
of a tile chip (e.g. 8x8 processors = 64-core chip).  Arnd suggested
looking at sysfs for that, so this change moves that information
to a pair of sysfs attributes (chip_width and chip_height) in the
/sys/devices/system/cpu directory.  We also put the "chip_serial"
and "chip_revision" information from our old /proc/tile/board file
as attributes in /sys/devices/system/cpu.

Other information collected via hypervisor APIs is now placed in
/sys/hypervisor.  We create a /sys/hypervisor/type file (holding the
constant string "tilera") to be parallel with the Xen use of
/sys/hypervisor/type holding "xen".  We create three top-level files,
"version" (the hypervisor's own version), "config_version" (the
version of the configuration file), and "hvconfig" (the contents of
the configuration file).  The remaining information from our old
/proc/tile/board and /proc/tile/switch files becomes an attribute
group appearing under /sys/hypervisor/board/.

Finally, after some feedback from Arnd Bergmann for the previous
version of this patch, the /proc/tile/hardwall file is split up into
two conceptual parts.  First, a directory /proc/tile/hardwall/ which
contains one file per active hardwall, each file named after the
hardwall's ID and holding a cpulist that says which cpus are enclosed by
the hardwall.  Second, a /proc/PID file "hardwall" that is either
empty (for non-hardwall-using processes) or contains the hardwall ID.

Finally, this change pushes the /proc/sys/tile/unaligned_fixup/
directory, with knobs controlling the kernel code for handling the
fixup of unaligned exceptions.

Reviewed-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarChris Metcalf <cmetcalf@tilera.com>
parent 7a0287df

arch/tile/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ config TILE 
	select GENERIC_IRQ_PROBE

	select GENERIC_PENDING_IRQ if SMP

	select GENERIC_IRQ_SHOW

	select SYS_HYPERVISOR



# FIXME: investigate whether we need/want these options.

#	select HAVE_IOREMAP_PROT

arch/tile/include/asm/hardwall.h

+12 −3
Original line number Diff line number Diff line
@@ -40,6 +40,10 @@ 
#define HARDWALL_DEACTIVATE \

 _IO(HARDWALL_IOCTL_BASE, _HARDWALL_DEACTIVATE)



#define _HARDWALL_GET_ID 4

#define HARDWALL_GET_ID \

 _IO(HARDWALL_IOCTL_BASE, _HARDWALL_GET_ID)



#ifndef __KERNEL__



/* This is the canonical name expected by userspace. */
@@ -47,9 +51,14 @@ 


#else



/* Hook for /proc/tile/hardwall. */

struct seq_file;

int proc_tile_hardwall_show(struct seq_file *sf, void *v);

/* /proc hooks for hardwall. */

struct proc_dir_entry;

#ifdef CONFIG_HARDWALL

void proc_tile_hardwall_init(struct proc_dir_entry *root);

int proc_pid_hardwall(struct task_struct *task, char *buffer);

#else

static inline void proc_tile_hardwall_init(struct proc_dir_entry *root) {}

#endif



#endif

arch/tile/kernel/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -5,7 +5,7 @@ 
extra-y := vmlinux.lds head_$(BITS).o

obj-y := backtrace.o entry.o init_task.o irq.o messaging.o \

	pci-dma.o proc.o process.o ptrace.o reboot.o \

	setup.o signal.o single_step.o stack.o sys.o time.o traps.o \

	setup.o signal.o single_step.o stack.o sys.o sysfs.o time.o traps.o \

	intvec_$(BITS).o regs_$(BITS).o tile-desc_$(BITS).o



obj-$(CONFIG_HARDWALL)		+= hardwall.o

arch/tile/kernel/hardwall.c

+66 −24
Original line number Diff line number Diff line
@@ -40,16 +40,25 @@ 
struct hardwall_info {

	struct list_head list;             /* "rectangles" list */

	struct list_head task_head;        /* head of tasks in this hardwall */

	struct cpumask cpumask;            /* cpus in the rectangle */

	int ulhc_x;                        /* upper left hand corner x coord */

	int ulhc_y;                        /* upper left hand corner y coord */

	int width;                         /* rectangle width */

	int height;                        /* rectangle height */

	int id;                            /* integer id for this hardwall */

	int teardown_in_progress;          /* are we tearing this one down? */

};



/* Currently allocated hardwall rectangles */

static LIST_HEAD(rectangles);



/* /proc/tile/hardwall */

static struct proc_dir_entry *hardwall_proc_dir;



/* Functions to manage files in /proc/tile/hardwall. */

static void hardwall_add_proc(struct hardwall_info *rect);

static void hardwall_remove_proc(struct hardwall_info *rect);



/*

 * Guard changes to the hardwall data structures.

 * This could be finer grained (e.g. one lock for the list of hardwall
@@ -105,6 +114,8 @@ static int setup_rectangle(struct hardwall_info *r, struct cpumask *mask) 
	r->ulhc_y = cpu_y(ulhc);

	r->width = cpu_x(lrhc) - r->ulhc_x + 1;

	r->height = cpu_y(lrhc) - r->ulhc_y + 1;

	cpumask_copy(&r->cpumask, mask);

	r->id = ulhc;   /* The ulhc cpu id can be the hardwall id. */



	/* Width and height must be positive */

	if (r->width <= 0 || r->height <= 0)
@@ -388,6 +399,9 @@ static struct hardwall_info *hardwall_create( 
	/* Set up appropriate hardwalling on all affected cpus. */

	hardwall_setup(rect);



	/* Create a /proc/tile/hardwall entry. */

	hardwall_add_proc(rect);



	return rect;

}
@@ -645,6 +659,9 @@ static void hardwall_destroy(struct hardwall_info *rect) 
	/* Restart switch and disable firewall. */

	on_each_cpu_mask(&mask, restart_udn_switch, NULL, 1);



	/* Remove the /proc/tile/hardwall entry. */

	hardwall_remove_proc(rect);



	/* Now free the rectangle from the list. */

	spin_lock_irqsave(&hardwall_lock, flags);

	BUG_ON(!list_empty(&rect->task_head));
@@ -654,33 +671,55 @@ static void hardwall_destroy(struct hardwall_info *rect) 
}





/*

 * Dump hardwall state via /proc; initialized in arch/tile/sys/proc.c.

 */

int proc_tile_hardwall_show(struct seq_file *sf, void *v)

static int hardwall_proc_show(struct seq_file *sf, void *v)

{

	struct hardwall_info *r;

	struct hardwall_info *rect = sf->private;

	char buf[256];



	if (udn_disabled) {

		seq_printf(sf, "%dx%d 0,0 pids:\n", smp_width, smp_height);

	int rc = cpulist_scnprintf(buf, sizeof(buf), &rect->cpumask);

	buf[rc++] = '\n';

	seq_write(sf, buf, rc);

	return 0;

}



	spin_lock_irq(&hardwall_lock);

	list_for_each_entry(r, &rectangles, list) {

		struct task_struct *p;

		seq_printf(sf, "%dx%d %d,%d pids:",

			   r->width, r->height, r->ulhc_x, r->ulhc_y);

		list_for_each_entry(p, &r->task_head, thread.hardwall_list) {

			unsigned int cpu = cpumask_first(&p->cpus_allowed);

			unsigned int x = cpu % smp_width;

			unsigned int y = cpu / smp_width;

			seq_printf(sf, " %d@%d,%d", p->pid, x, y);

static int hardwall_proc_open(struct inode *inode,

			      struct file *file)

{

	return single_open(file, hardwall_proc_show, PDE(inode)->data);

}



static const struct file_operations hardwall_proc_fops = {

	.open		= hardwall_proc_open,

	.read		= seq_read,

	.llseek		= seq_lseek,

	.release	= single_release,

};



static void hardwall_add_proc(struct hardwall_info *rect)

{

	char buf[64];

	snprintf(buf, sizeof(buf), "%d", rect->id);

	proc_create_data(buf, 0444, hardwall_proc_dir,

			 &hardwall_proc_fops, rect);

}

		seq_printf(sf, "\n");



static void hardwall_remove_proc(struct hardwall_info *rect)

{

	char buf[64];

	snprintf(buf, sizeof(buf), "%d", rect->id);

	remove_proc_entry(buf, hardwall_proc_dir);

}

	spin_unlock_irq(&hardwall_lock);

	return 0;



int proc_pid_hardwall(struct task_struct *task, char *buffer)

{

	struct hardwall_info *rect = task->thread.hardwall;

	return rect ? sprintf(buffer, "%d\n", rect->id) : 0;

}



void proc_tile_hardwall_init(struct proc_dir_entry *root)

{

	if (!udn_disabled)

		hardwall_proc_dir = proc_mkdir("hardwall", root);

}
@@ -716,6 +755,9 @@ static long hardwall_ioctl(struct file *file, unsigned int a, unsigned long b) 
			return -EINVAL;

		return hardwall_deactivate(current);



	case _HARDWALL_GET_ID:

		return rect ? rect->id : -EINVAL;



	default:

		return -EINVAL;

	}

arch/tile/kernel/proc.c

+73 −0
Original line number Diff line number Diff line
@@ -27,6 +27,7 @@ 
#include <asm/processor.h>

#include <asm/sections.h>

#include <asm/homecache.h>

#include <asm/hardwall.h>

#include <arch/chip.h>
@@ -88,3 +89,75 @@ const struct seq_operations cpuinfo_op = { 
	.stop	= c_stop,

	.show	= show_cpuinfo,

};



/*

 * Support /proc/tile directory

 */



static int __init proc_tile_init(void)

{

	struct proc_dir_entry *root = proc_mkdir("tile", NULL);

	if (root == NULL)

		return 0;



	proc_tile_hardwall_init(root);



	return 0;

}



arch_initcall(proc_tile_init);



/*

 * Support /proc/sys/tile directory

 */



#ifndef __tilegx__  /* FIXME: GX: no support for unaligned access yet */

static ctl_table unaligned_subtable[] = {

	{

		.procname	= "enabled",

		.data		= &unaligned_fixup,

		.maxlen		= sizeof(int),

		.mode		= 0644,

		.proc_handler	= &proc_dointvec

	},

	{

		.procname	= "printk",

		.data		= &unaligned_printk,

		.maxlen		= sizeof(int),

		.mode		= 0644,

		.proc_handler	= &proc_dointvec

	},

	{

		.procname	= "count",

		.data		= &unaligned_fixup_count,

		.maxlen		= sizeof(int),

		.mode		= 0644,

		.proc_handler	= &proc_dointvec

	},

	{}

};



static ctl_table unaligned_table[] = {

	{

		.procname	= "unaligned_fixup",

		.mode		= 0555,

		.child		= unaligned_subtable

	},

	{}

};

#endif



static struct ctl_path tile_path[] = {

	{ .procname = "tile" },

	{ }

};



static int __init proc_sys_tile_init(void)

{

#ifndef __tilegx__  /* FIXME: GX: no support for unaligned access yet */

	register_sysctl_paths(tile_path, unaligned_table);

#endif

	return 0;

}



arch_initcall(proc_sys_tile_init);

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