Commit 67acd8b4 authored by Linus Torvalds's avatar Linus Torvalds

Merge git://git.kernel.org/pub/scm/linux/kernel/git/arjan/linux-2.6-async

* git://git.kernel.org/pub/scm/linux/kernel/git/arjan/linux-2.6-async:
  async: don't do the initcall stuff post boot
  bootchart: improve output based on Dave Jones' feedback
  async: make the final inode deletion an asynchronous event
  fastboot: Make libata initialization even more async
  fastboot: make the libata port scan asynchronous
  fastboot: make scsi probes asynchronous
  async: Asynchronous function calls to speed up kernel boot
parents b13d3720 ad160d23
......@@ -56,6 +56,7 @@
#include <linux/workqueue.h>
#include <linux/scatterlist.h>
#include <linux/io.h>
#include <linux/async.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_host.h>
......@@ -5909,6 +5910,54 @@ void ata_host_init(struct ata_host *host, struct device *dev,
host->ops = ops;
}
static void async_port_probe(void *data, async_cookie_t cookie)
{
int rc;
struct ata_port *ap = data;
/* probe */
if (ap->ops->error_handler) {
struct ata_eh_info *ehi = &ap->link.eh_info;
unsigned long flags;
ata_port_probe(ap);
/* kick EH for boot probing */
spin_lock_irqsave(ap->lock, flags);
ehi->probe_mask |= ATA_ALL_DEVICES;
ehi->action |= ATA_EH_RESET | ATA_EH_LPM;
ehi->flags |= ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET;
ap->pflags &= ~ATA_PFLAG_INITIALIZING;
ap->pflags |= ATA_PFLAG_LOADING;
ata_port_schedule_eh(ap);
spin_unlock_irqrestore(ap->lock, flags);
/* wait for EH to finish */
ata_port_wait_eh(ap);
} else {
DPRINTK("ata%u: bus probe begin\n", ap->print_id);
rc = ata_bus_probe(ap);
DPRINTK("ata%u: bus probe end\n", ap->print_id);
if (rc) {
/* FIXME: do something useful here?
* Current libata behavior will
* tear down everything when
* the module is removed
* or the h/w is unplugged.
*/
}
}
/* in order to keep device order, we need to synchronize at this point */
async_synchronize_cookie(cookie);
ata_scsi_scan_host(ap, 1);
}
/**
* ata_host_register - register initialized ATA host
* @host: ATA host to register
......@@ -5988,52 +6037,9 @@ int ata_host_register(struct ata_host *host, struct scsi_host_template *sht)
DPRINTK("probe begin\n");
for (i = 0; i < host->n_ports; i++) {
struct ata_port *ap = host->ports[i];
/* probe */
if (ap->ops->error_handler) {
struct ata_eh_info *ehi = &ap->link.eh_info;
unsigned long flags;
ata_port_probe(ap);
/* kick EH for boot probing */
spin_lock_irqsave(ap->lock, flags);
ehi->probe_mask |= ATA_ALL_DEVICES;
ehi->action |= ATA_EH_RESET | ATA_EH_LPM;
ehi->flags |= ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET;
ap->pflags &= ~ATA_PFLAG_INITIALIZING;
ap->pflags |= ATA_PFLAG_LOADING;
ata_port_schedule_eh(ap);
spin_unlock_irqrestore(ap->lock, flags);
/* wait for EH to finish */
ata_port_wait_eh(ap);
} else {
DPRINTK("ata%u: bus probe begin\n", ap->print_id);
rc = ata_bus_probe(ap);
DPRINTK("ata%u: bus probe end\n", ap->print_id);
if (rc) {
/* FIXME: do something useful here?
* Current libata behavior will
* tear down everything when
* the module is removed
* or the h/w is unplugged.
*/
}
}
}
/* probes are done, now scan each port's disk(s) */
DPRINTK("host probe begin\n");
for (i = 0; i < host->n_ports; i++) {
struct ata_port *ap = host->ports[i];
ata_scsi_scan_host(ap, 1);
async_schedule(async_port_probe, ap);
}
DPRINTK("probe end\n");
return 0;
}
......
......@@ -32,6 +32,7 @@
#include <linux/delay.h>
#include <linux/kthread.h>
#include <linux/spinlock.h>
#include <linux/async.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
......@@ -179,6 +180,8 @@ int scsi_complete_async_scans(void)
spin_unlock(&async_scan_lock);
kfree(data);
/* Synchronize async operations globally */
async_synchronize_full();
return 0;
}
......
......@@ -48,6 +48,7 @@
#include <linux/delay.h>
#include <linux/mutex.h>
#include <linux/string_helpers.h>
#include <linux/async.h>
#include <asm/uaccess.h>
#include <scsi/scsi.h>
......@@ -1802,6 +1803,71 @@ static int sd_format_disk_name(char *prefix, int index, char *buf, int buflen)
return 0;
}
/*
* The asynchronous part of sd_probe
*/
static void sd_probe_async(void *data, async_cookie_t cookie)
{
struct scsi_disk *sdkp = data;
struct scsi_device *sdp;
struct gendisk *gd;
u32 index;
struct device *dev;
sdp = sdkp->device;
gd = sdkp->disk;
index = sdkp->index;
dev = &sdp->sdev_gendev;
if (!sdp->request_queue->rq_timeout) {
if (sdp->type != TYPE_MOD)
blk_queue_rq_timeout(sdp->request_queue, SD_TIMEOUT);
else
blk_queue_rq_timeout(sdp->request_queue,
SD_MOD_TIMEOUT);
}
device_initialize(&sdkp->dev);
sdkp->dev.parent = &sdp->sdev_gendev;
sdkp->dev.class = &sd_disk_class;
strncpy(sdkp->dev.bus_id, sdp->sdev_gendev.bus_id, BUS_ID_SIZE);
if (device_add(&sdkp->dev))
goto out_free_index;
get_device(&sdp->sdev_gendev);
if (index < SD_MAX_DISKS) {
gd->major = sd_major((index & 0xf0) >> 4);
gd->first_minor = ((index & 0xf) << 4) | (index & 0xfff00);
gd->minors = SD_MINORS;
}
gd->fops = &sd_fops;
gd->private_data = &sdkp->driver;
gd->queue = sdkp->device->request_queue;
sd_revalidate_disk(gd);
blk_queue_prep_rq(sdp->request_queue, sd_prep_fn);
gd->driverfs_dev = &sdp->sdev_gendev;
gd->flags = GENHD_FL_EXT_DEVT | GENHD_FL_DRIVERFS;
if (sdp->removable)
gd->flags |= GENHD_FL_REMOVABLE;
dev_set_drvdata(dev, sdkp);
add_disk(gd);
sd_dif_config_host(sdkp);
sd_printk(KERN_NOTICE, sdkp, "Attached SCSI %sdisk\n",
sdp->removable ? "removable " : "");
return;
out_free_index:
ida_remove(&sd_index_ida, index);
}
/**
* sd_probe - called during driver initialization and whenever a
* new scsi device is attached to the system. It is called once
......@@ -1865,48 +1931,7 @@ static int sd_probe(struct device *dev)
sdkp->openers = 0;
sdkp->previous_state = 1;
if (!sdp->request_queue->rq_timeout) {
if (sdp->type != TYPE_MOD)
blk_queue_rq_timeout(sdp->request_queue, SD_TIMEOUT);
else
blk_queue_rq_timeout(sdp->request_queue,
SD_MOD_TIMEOUT);
}
device_initialize(&sdkp->dev);
sdkp->dev.parent = &sdp->sdev_gendev;
sdkp->dev.class = &sd_disk_class;
strncpy(sdkp->dev.bus_id, sdp->sdev_gendev.bus_id, BUS_ID_SIZE);
if (device_add(&sdkp->dev))
goto out_free_index;
get_device(&sdp->sdev_gendev);
if (index < SD_MAX_DISKS) {
gd->major = sd_major((index & 0xf0) >> 4);
gd->first_minor = ((index & 0xf) << 4) | (index & 0xfff00);
gd->minors = SD_MINORS;
}
gd->fops = &sd_fops;
gd->private_data = &sdkp->driver;
gd->queue = sdkp->device->request_queue;
sd_revalidate_disk(gd);
blk_queue_prep_rq(sdp->request_queue, sd_prep_fn);
gd->driverfs_dev = &sdp->sdev_gendev;
gd->flags = GENHD_FL_EXT_DEVT | GENHD_FL_DRIVERFS;
if (sdp->removable)
gd->flags |= GENHD_FL_REMOVABLE;
dev_set_drvdata(dev, sdkp);
add_disk(gd);
sd_dif_config_host(sdkp);
sd_printk(KERN_NOTICE, sdkp, "Attached SCSI %sdisk\n",
sdp->removable ? "removable " : "");
async_schedule(sd_probe_async, sdkp);
return 0;
......
......@@ -22,6 +22,7 @@
#include <linux/bootmem.h>
#include <linux/inotify.h>
#include <linux/mount.h>
#include <linux/async.h>
/*
* This is needed for the following functions:
......@@ -1138,16 +1139,11 @@ EXPORT_SYMBOL(remove_inode_hash);
* I_FREEING is set so that no-one will take a new reference to the inode while
* it is being deleted.
*/
void generic_delete_inode(struct inode *inode)
static void generic_delete_inode_async(void *data, async_cookie_t cookie)
{
struct inode *inode = data;
const struct super_operations *op = inode->i_sb->s_op;
list_del_init(&inode->i_list);
list_del_init(&inode->i_sb_list);
inode->i_state |= I_FREEING;
inodes_stat.nr_inodes--;
spin_unlock(&inode_lock);
security_inode_delete(inode);
if (op->delete_inode) {
......@@ -1171,6 +1167,16 @@ void generic_delete_inode(struct inode *inode)
destroy_inode(inode);
}
void generic_delete_inode(struct inode *inode)
{
list_del_init(&inode->i_list);
list_del_init(&inode->i_sb_list);
inode->i_state |= I_FREEING;
inodes_stat.nr_inodes--;
spin_unlock(&inode_lock);
async_schedule_special(generic_delete_inode_async, inode, &inode->i_sb->s_async_list);
}
EXPORT_SYMBOL(generic_delete_inode);
static void generic_forget_inode(struct inode *inode)
......
......@@ -38,6 +38,7 @@
#include <linux/kobject.h>
#include <linux/mutex.h>
#include <linux/file.h>
#include <linux/async.h>
#include <asm/uaccess.h>
#include "internal.h"
......@@ -71,6 +72,7 @@ static struct super_block *alloc_super(struct file_system_type *type)
INIT_HLIST_HEAD(&s->s_anon);
INIT_LIST_HEAD(&s->s_inodes);
INIT_LIST_HEAD(&s->s_dentry_lru);
INIT_LIST_HEAD(&s->s_async_list);
init_rwsem(&s->s_umount);
mutex_init(&s->s_lock);
lockdep_set_class(&s->s_umount, &type->s_umount_key);
......@@ -289,11 +291,18 @@ void generic_shutdown_super(struct super_block *sb)
{
const struct super_operations *sop = sb->s_op;
if (sb->s_root) {
shrink_dcache_for_umount(sb);
fsync_super(sb);
lock_super(sb);
sb->s_flags &= ~MS_ACTIVE;
/*
* wait for asynchronous fs operations to finish before going further
*/
async_synchronize_full_special(&sb->s_async_list);
/* bad name - it should be evict_inodes() */
invalidate_inodes(sb);
lock_kernel();
......@@ -449,6 +458,7 @@ void sync_filesystems(int wait)
if (sb->s_flags & MS_RDONLY)
continue;
sb->s_need_sync_fs = 1;
async_synchronize_full_special(&sb->s_async_list);
}
restart:
......
/*
* async.h: Asynchronous function calls for boot performance
*
* (C) Copyright 2009 Intel Corporation
* Author: Arjan van de Ven <arjan@linux.intel.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; version 2
* of the License.
*/
#include <linux/types.h>
#include <linux/list.h>
typedef u64 async_cookie_t;
typedef void (async_func_ptr) (void *data, async_cookie_t cookie);
extern async_cookie_t async_schedule(async_func_ptr *ptr, void *data);
extern async_cookie_t async_schedule_special(async_func_ptr *ptr, void *data, struct list_head *list);
extern void async_synchronize_full(void);
extern void async_synchronize_full_special(struct list_head *list);
extern void async_synchronize_cookie(async_cookie_t cookie);
extern void async_synchronize_cookie_special(async_cookie_t cookie, struct list_head *list);
......@@ -1184,6 +1184,11 @@ struct super_block {
* generic_show_options()
*/
char *s_options;
/*
* storage for asynchronous operations
*/
struct list_head s_async_list;
};
extern struct timespec current_fs_time(struct super_block *sb);
......
......@@ -13,6 +13,7 @@
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/initrd.h>
#include <linux/async.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_fs_sb.h>
......@@ -372,6 +373,7 @@ void __init prepare_namespace(void)
/* wait for the known devices to complete their probing */
while (driver_probe_done() != 0)
msleep(100);
async_synchronize_full();
md_run_setup();
......
......@@ -62,6 +62,7 @@
#include <linux/signal.h>
#include <linux/idr.h>
#include <linux/ftrace.h>
#include <linux/async.h>
#include <trace/boot.h>
#include <asm/io.h>
......@@ -685,7 +686,7 @@ asmlinkage void __init start_kernel(void)
rest_init();
}
static int initcall_debug;
int initcall_debug;
core_param(initcall_debug, initcall_debug, bool, 0644);
int do_one_initcall(initcall_t fn)
......@@ -786,6 +787,8 @@ static void run_init_process(char *init_filename)
*/
static noinline int init_post(void)
{
/* need to finish all async __init code before freeing the memory */
async_synchronize_full();
free_initmem();
unlock_kernel();
mark_rodata_ro();
......
......@@ -9,7 +9,8 @@ obj-y = sched.o fork.o exec_domain.o panic.o printk.o \
rcupdate.o extable.o params.o posix-timers.o \
kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \
hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \
notifier.o ksysfs.o pm_qos_params.o sched_clock.o cred.o
notifier.o ksysfs.o pm_qos_params.o sched_clock.o cred.o \
async.o
ifdef CONFIG_FUNCTION_TRACER
# Do not trace debug files and internal ftrace files
......
/*
* async.c: Asynchronous function calls for boot performance
*
* (C) Copyright 2009 Intel Corporation
* Author: Arjan van de Ven <arjan@linux.intel.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; version 2
* of the License.
*/
/*
Goals and Theory of Operation
The primary goal of this feature is to reduce the kernel boot time,
by doing various independent hardware delays and discovery operations
decoupled and not strictly serialized.
More specifically, the asynchronous function call concept allows
certain operations (primarily during system boot) to happen
asynchronously, out of order, while these operations still
have their externally visible parts happen sequentially and in-order.
(not unlike how out-of-order CPUs retire their instructions in order)
Key to the asynchronous function call implementation is the concept of
a "sequence cookie" (which, although it has an abstracted type, can be
thought of as a monotonically incrementing number).
The async core will assign each scheduled event such a sequence cookie and
pass this to the called functions.
The asynchronously called function should before doing a globally visible
operation, such as registering device numbers, call the
async_synchronize_cookie() function and pass in its own cookie. The
async_synchronize_cookie() function will make sure that all asynchronous
operations that were scheduled prior to the operation corresponding with the
cookie have completed.
Subsystem/driver initialization code that scheduled asynchronous probe
functions, but which shares global resources with other drivers/subsystems
that do not use the asynchronous call feature, need to do a full
synchronization with the async_synchronize_full() function, before returning
from their init function. This is to maintain strict ordering between the
asynchronous and synchronous parts of the kernel.
*/
#include <linux/async.h>
#include <linux/module.h>
#include <linux/wait.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/kthread.h>
#include <asm/atomic.h>
static async_cookie_t next_cookie = 1;
#define MAX_THREADS 256
#define MAX_WORK 32768
static LIST_HEAD(async_pending);
static LIST_HEAD(async_running);
static DEFINE_SPINLOCK(async_lock);
struct async_entry {
struct list_head list;
async_cookie_t cookie;
async_func_ptr *func;
void *data;
struct list_head *running;
};
static DECLARE_WAIT_QUEUE_HEAD(async_done);
static DECLARE_WAIT_QUEUE_HEAD(async_new);
static atomic_t entry_count;
static atomic_t thread_count;
extern int initcall_debug;
/*
* MUST be called with the lock held!
*/
static async_cookie_t __lowest_in_progress(struct list_head *running)
{
struct async_entry *entry;
if (!list_empty(&async_pending)) {
entry = list_first_entry(&async_pending,
struct async_entry, list);
return entry->cookie;
} else if (!list_empty(running)) {
entry = list_first_entry(running,
struct async_entry, list);
return entry->cookie;
} else {
/* nothing in progress... next_cookie is "infinity" */
return next_cookie;
}
}
/*
* pick the first pending entry and run it
*/
static void run_one_entry(void)
{
unsigned long flags;
struct async_entry *entry;
ktime_t calltime, delta, rettime;
/* 1) pick one task from the pending queue */
spin_lock_irqsave(&async_lock, flags);
if (list_empty(&async_pending))
goto out;
entry = list_first_entry(&async_pending, struct async_entry, list);
/* 2) move it to the running queue */
list_del(&entry->list);
list_add_tail(&entry->list, &async_running);
spin_unlock_irqrestore(&async_lock, flags);
/* 3) run it (and print duration)*/
if (initcall_debug && system_state == SYSTEM_BOOTING) {
printk("calling %lli_%pF @ %i\n", entry->cookie, entry->func, task_pid_nr(current));
calltime = ktime_get();
}
entry->func(entry->data, entry->cookie);
if (initcall_debug && system_state == SYSTEM_BOOTING) {
rettime = ktime_get();
delta = ktime_sub(rettime, calltime);
printk("initcall %lli_%pF returned 0 after %lld usecs\n", entry->cookie,
entry->func, ktime_to_ns(delta) >> 10);
}
/* 4) remove it from the running queue */
spin_lock_irqsave(&async_lock, flags);
list_del(&entry->list);
/* 5) free the entry */
kfree(entry);
atomic_dec(&entry_count);
spin_unlock_irqrestore(&async_lock, flags);
/* 6) wake up any waiters. */
wake_up(&async_done);
return;
out:
spin_unlock_irqrestore(&async_lock, flags);
}
static async_cookie_t __async_schedule(async_func_ptr *ptr, void *data, struct list_head *running)
{
struct async_entry *entry;
unsigned long flags;
async_cookie_t newcookie;
/* allow irq-off callers */
entry = kzalloc(sizeof(struct async_entry), GFP_ATOMIC);
/*
* If we're out of memory or if there's too much work
* pending already, we execute synchronously.
*/
if (!entry || atomic_read(&entry_count) > MAX_WORK) {
kfree(entry);
spin_lock_irqsave(&async_lock, flags);
newcookie = next_cookie++;
spin_unlock_irqrestore(&async_lock, flags);
/* low on memory.. run synchronously */
ptr(data, newcookie);
return newcookie;
}
entry->func = ptr;
entry->data = data;
entry->running = running;
spin_lock_irqsave(&async_lock, flags);
newcookie = entry->cookie = next_cookie++;
list_add_tail(&entry->list, &async_pending);
atomic_inc(&entry_count);
spin_unlock_irqrestore(&async_lock, flags);
wake_up(&async_new);
return newcookie;
}
async_cookie_t async_schedule(async_func_ptr *ptr, void *data)
{
return __async_schedule(ptr, data, &async_pending);
}
EXPORT_SYMBOL_GPL(async_schedule);
async_cookie_t async_schedule_special(async_func_ptr *ptr, void *data, struct list_head *running)
{
return __async_schedule(ptr, data, running);
}
EXPORT_SYMBOL_GPL(async_schedule_special);
void async_synchronize_full(void)
{
async_synchronize_cookie(next_cookie);
}
EXPORT_SYMBOL_GPL(async_synchronize_full);
void async_synchronize_full_special(struct list_head *list)
{
async_synchronize_cookie_special(next_cookie, list);
}
EXPORT_SYMBOL_GPL(async_synchronize_full_special);
void async_synchronize_cookie_special(async_cookie_t cookie, struct list_head *running)
{
ktime_t starttime, delta, endtime;
if (initcall_debug && system_state == SYSTEM_BOOTING) {
printk("async_waiting @ %i\n", task_pid_nr(current));
starttime = ktime_get();
}
wait_event(async_done, __lowest_in_progress(running) >= cookie);
if (initcall_debug && system_state == SYSTEM_BOOTING) {
endtime = ktime_get();
delta = ktime_sub(endtime, starttime);
printk("async_continuing @ %i after %lli usec\n",
task_pid_nr(current), ktime_to_ns(delta) >> 10);
}
}
EXPORT_SYMBOL_GPL(async_synchronize_cookie_special);
void async_synchronize_cookie(async_cookie_t cookie)
{
async_synchronize_cookie_special(cookie, &async_running);
}
EXPORT_SYMBOL_GPL(async_synchronize_cookie);
static int async_thread(void *unused)
{
DECLARE_WAITQUEUE(wq, current);
add_wait_queue(&async_new, &wq);
while (!kthread_should_stop()) {
int ret = HZ;
set_current_state(TASK_INTERRUPTIBLE);
/*
* check the list head without lock.. false positives
* are dealt with inside run_one_entry() while holding
* the lock.
*/
rmb();
if (!list_empty(&async_pending))
run_one_entry();
else
ret = schedule_timeout(HZ);
if (ret == 0) {
/*
* we timed out, this means we as thread are redundant.
* we sign off and die, but we to avoid any races there
* is a last-straw check to see if work snuck in.
*/
atomic_dec(&thread_count);
wmb(); /* manager must see our departure first */
if (list_empty(&async_pending))
break;
/*
* woops work came in between us timing out and us
* signing off; we need to stay alive and keep working.
*/
atomic_inc(&thread_count);
}
}
remove_wait_queue(&async_new, &wq);
return 0;
}
static int async_manager_thread(void *unused)
{
DECLARE_WAITQUEUE(wq, current);
add_wait_queue(&async_new, &wq);
while (!kthread_should_stop()) {
int tc, ec;
set_current_state(TASK_INTERRUPTIBLE);
tc = atomic_read(&thread_count);
rmb();
ec = atomic_read(&entry_count);
while (tc < ec && tc < MAX_THREADS) {
kthread_run(async_thread, NULL, "async/%i", tc);
atomic_inc(&thread_count);
tc++;
}
schedule();
}
remove_wait_queue(&async_new, &wq);
return 0;
}
static int __init async_init(void)
{
kthread_run(async_manager_thread, NULL, "async/mgr");
return 0;
}
core_initcall(async_init);
......@@ -10,6 +10,7 @@
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/async.h>
#include "internals.h"
......@@ -34,6 +35,10 @@ unsigned long probe_irq_on(void)
unsigned int status;
int i;
/*
* quiesce the kernel, or at least the asynchronous portion
*/
async_synchronize_full();
mutex_lock(&probing_active);
/*
* something may have generated an irq long ago and we want to
......
......@@ -50,6 +50,7 @@
#include <asm/sections.h>
#include <linux/tracepoint.h>
#include <linux/ftrace.h>
#include <linux/async.h>
#if 0
#define DEBUGP printk
......@@ -816,6 +817,7 @@ sys_delete_module(const char __user *name_user, unsigned int flags)
mod->exit();
blocking_notifier_call_chain(&module_notify_list,
MODULE_STATE_GOING, mod);
async_synchronize_full();
mutex_lock(&module_mutex);
/* Store the name of the last unloaded module for diagnostic purposes */
strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
......
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