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Commit 34c0dad7 authored by Michael Holzheu's avatar Michael Holzheu Committed by Martin Schwidefsky
Browse files

s390/hypfs: Add diagnose 0c support 



With this feature, you can read the CPU performance metrics provided by the
z/VM diagnose 0C. This then allows to get the management time for each
online CPU of the guest where the diagnose is executed.

The new debugfs file /sys/kernel/debug/s390_hypfs/diag_0c exports the
diag0C binary data to user space via an open/read/close interface.

The binary data consists out of a header structure followed by an
array that contains the diagnose 0c data for each online CPU.

Signed-off-by: default avatarMichael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 45cce4cc

arch/s390/hypfs/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -5,3 +5,4 @@ 
obj-$(CONFIG_S390_HYPFS_FS) += s390_hypfs.o



s390_hypfs-objs := inode.o hypfs_diag.o hypfs_vm.o hypfs_dbfs.o hypfs_sprp.o

s390_hypfs-objs += hypfs_diag0c.o

arch/s390/hypfs/hypfs.h

+4 −0
Original line number Diff line number Diff line
@@ -37,6 +37,10 @@ extern int hypfs_vm_init(void); 
extern void hypfs_vm_exit(void);

extern int hypfs_vm_create_files(struct dentry *root);



/* VM diagnose 0c */

int hypfs_diag0c_init(void);

void hypfs_diag0c_exit(void);



/* Set Partition-Resource Parameter */

int hypfs_sprp_init(void);

void hypfs_sprp_exit(void);

arch/s390/hypfs/hypfs_diag0c.c

0 → 100644
+139 −0
Original line number Diff line number Diff line 
/*

 * Hypervisor filesystem for Linux on s390

 *

 * Diag 0C implementation

 *

 * Copyright IBM Corp. 2014

 */



#include <linux/slab.h>

#include <linux/cpu.h>

#include <asm/hypfs.h>

#include "hypfs.h"



#define DBFS_D0C_HDR_VERSION 0



/*

 * Execute diagnose 0c in 31 bit mode

 */

static void diag0c(struct hypfs_diag0c_entry *entry)

{

	asm volatile (

#ifdef CONFIG_64BIT

		"	sam31\n"

		"	diag	%0,%0,0x0c\n"

		"	sam64\n"

#else

		"	diag %0,%0,0x0c\n"

#endif

		: /* no output register */

		: "a" (entry)

		: "memory");

}



/*

 * Get hypfs_diag0c_entry from CPU vector and store diag0c data

 */

static void diag0c_fn(void *data)

{

	diag0c(((void **) data)[smp_processor_id()]);

}



/*

 * Allocate buffer and store diag 0c data

 */

static void *diag0c_store(unsigned int *count)

{

	struct hypfs_diag0c_data *diag0c_data;

	unsigned int cpu_count, cpu, i;

	void **cpu_vec;



	get_online_cpus();

	cpu_count = num_online_cpus();

	cpu_vec = kmalloc(sizeof(*cpu_vec) * num_possible_cpus(), GFP_KERNEL);

	if (!cpu_vec)

		goto fail_put_online_cpus;

	/* Note: Diag 0c needs 8 byte alignment and real storage */

	diag0c_data = kzalloc(sizeof(struct hypfs_diag0c_hdr) +

			      cpu_count * sizeof(struct hypfs_diag0c_entry),

			      GFP_KERNEL | GFP_DMA);

	if (!diag0c_data)

		goto fail_kfree_cpu_vec;

	i = 0;

	/* Fill CPU vector for each online CPU */

	for_each_online_cpu(cpu) {

		diag0c_data->entry[i].cpu = cpu;

		cpu_vec[cpu] = &diag0c_data->entry[i++];

	}

	/* Collect data all CPUs */

	on_each_cpu(diag0c_fn, cpu_vec, 1);

	*count = cpu_count;

	kfree(cpu_vec);

	put_online_cpus();

	return diag0c_data;



fail_kfree_cpu_vec:

	kfree(cpu_vec);

fail_put_online_cpus:

	put_online_cpus();

	return ERR_PTR(-ENOMEM);

}



/*

 * Hypfs DBFS callback: Free diag 0c data

 */

static void dbfs_diag0c_free(const void *data)

{

	kfree(data);

}



/*

 * Hypfs DBFS callback: Create diag 0c data

 */

static int dbfs_diag0c_create(void **data, void **data_free_ptr, size_t *size)

{

	struct hypfs_diag0c_data *diag0c_data;

	unsigned int count;



	diag0c_data = diag0c_store(&count);

	if (IS_ERR(diag0c_data))

		return PTR_ERR(diag0c_data);

	memset(&diag0c_data->hdr, 0, sizeof(diag0c_data->hdr));

	get_tod_clock_ext(diag0c_data->hdr.tod_ext);

	diag0c_data->hdr.len = count * sizeof(struct hypfs_diag0c_entry);

	diag0c_data->hdr.version = DBFS_D0C_HDR_VERSION;

	diag0c_data->hdr.count = count;

	*data = diag0c_data;

	*data_free_ptr = diag0c_data;

	*size = diag0c_data->hdr.len + sizeof(struct hypfs_diag0c_hdr);

	return 0;

}



/*

 * Hypfs DBFS file structure

 */

static struct hypfs_dbfs_file dbfs_file_0c = {

	.name		= "diag_0c",

	.data_create	= dbfs_diag0c_create,

	.data_free	= dbfs_diag0c_free,

};



/*

 * Initialize diag 0c interface for z/VM

 */

int __init hypfs_diag0c_init(void)

{

	if (!MACHINE_IS_VM)

		return 0;

	return hypfs_dbfs_create_file(&dbfs_file_0c);

}



/*

 * Shutdown diag 0c interface for z/VM

 */

void hypfs_diag0c_exit(void)

{

	if (!MACHINE_IS_VM)

		return;

	hypfs_dbfs_remove_file(&dbfs_file_0c);

}

arch/s390/hypfs/inode.c

+8 −1
Original line number Diff line number Diff line
@@ -482,10 +482,14 @@ static int __init hypfs_init(void) 
		rc = -ENODATA;

		goto fail_hypfs_vm_exit;

	}

	if (hypfs_diag0c_init()) {

		rc = -ENODATA;

		goto fail_hypfs_sprp_exit;

	}

	s390_kobj = kobject_create_and_add("s390", hypervisor_kobj);

	if (!s390_kobj) {

		rc = -ENOMEM;

		goto fail_hypfs_sprp_exit;

		goto fail_hypfs_diag0c_exit;

	}

	rc = register_filesystem(&hypfs_type);

	if (rc)
@@ -494,6 +498,8 @@ static int __init hypfs_init(void) 


fail_filesystem:

	kobject_put(s390_kobj);

fail_hypfs_diag0c_exit:

	hypfs_diag0c_exit();

fail_hypfs_sprp_exit:

	hypfs_sprp_exit();

fail_hypfs_vm_exit:
@@ -510,6 +516,7 @@ static void __exit hypfs_exit(void) 
{

	unregister_filesystem(&hypfs_type);

	kobject_put(s390_kobj);

	hypfs_diag0c_exit();

	hypfs_sprp_exit();

	hypfs_vm_exit();

	hypfs_diag_exit();

arch/s390/include/uapi/asm/hypfs.h

+32 −3
Original line number Diff line number Diff line 
/*

 * IOCTL interface for hypfs

 * Structures for hypfs interface

 *

 * Copyright IBM Corp. 2013

 *

 * Author: Martin Schwidefsky <schwidefsky@de.ibm.com>

 */



#ifndef _ASM_HYPFS_CTL_H

#define _ASM_HYPFS_CTL_H

#ifndef _ASM_HYPFS_H

#define _ASM_HYPFS_H



#include <linux/types.h>



/*

 * IOCTL for binary interface /sys/kernel/debug/diag_304

 */

struct hypfs_diag304 {

	__u32	args[2];

	__u64	data;
@@ -22,4 +25,30 @@ struct hypfs_diag304 { 
#define HYPFS_DIAG304 \

	_IOWR(HYPFS_IOCTL_MAGIC, 0x20, struct hypfs_diag304)



/*

 * Structures for binary interface /sys/kernel/debug/diag_0c

 */

struct hypfs_diag0c_hdr {

	__u64	len;		/* Length of diag0c buffer without header */

	__u16	version;	/* Version of header */

	char	reserved1[6];	/* Reserved */

	char	tod_ext[16];	/* TOD clock for diag0c */

	__u64	count;		/* Number of entries (CPUs) in diag0c array */

	char	reserved2[24];	/* Reserved */

};



struct hypfs_diag0c_entry {

	char	date[8];	/* MM/DD/YY in EBCDIC */

	char	time[8];	/* HH:MM:SS in EBCDIC */

	__u64	virtcpu;	/* Virtual time consumed by the virt CPU (us) */

	__u64	totalproc;	/* Total of virtual and simulation time (us) */

	__u32	cpu;		/* Linux logical CPU number */

	__u32	reserved;	/* Align to 8 byte */

};



struct hypfs_diag0c_data {

	struct hypfs_diag0c_hdr		hdr;		/* 64 byte header */

	struct hypfs_diag0c_entry	entry[];	/* diag0c entry array */

};



#endif