Commit e2688f00 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'blk-softirq' of git://brick.kernel.dk/data/git/linux-2.6-block

Manual merge for trivial #include changes
parents 356cebea a9925a06
......@@ -26,6 +26,8 @@
#include <linux/slab.h>
#include <linux/swap.h>
#include <linux/writeback.h>
#include <linux/interrupt.h>
#include <linux/cpu.h>
/*
* for max sense size
......@@ -61,13 +63,15 @@ static wait_queue_head_t congestion_wqh[2] = {
/*
* Controlling structure to kblockd
*/
static struct workqueue_struct *kblockd_workqueue;
static struct workqueue_struct *kblockd_workqueue;
unsigned long blk_max_low_pfn, blk_max_pfn;
EXPORT_SYMBOL(blk_max_low_pfn);
EXPORT_SYMBOL(blk_max_pfn);
static DEFINE_PER_CPU(struct list_head, blk_cpu_done);
/* Amount of time in which a process may batch requests */
#define BLK_BATCH_TIME (HZ/50UL)
......@@ -206,6 +210,13 @@ void blk_queue_merge_bvec(request_queue_t *q, merge_bvec_fn *mbfn)
EXPORT_SYMBOL(blk_queue_merge_bvec);
void blk_queue_softirq_done(request_queue_t *q, softirq_done_fn *fn)
{
q->softirq_done_fn = fn;
}
EXPORT_SYMBOL(blk_queue_softirq_done);
/**
* blk_queue_make_request - define an alternate make_request function for a device
* @q: the request queue for the device to be affected
......@@ -269,6 +280,7 @@ EXPORT_SYMBOL(blk_queue_make_request);
static inline void rq_init(request_queue_t *q, struct request *rq)
{
INIT_LIST_HEAD(&rq->queuelist);
INIT_LIST_HEAD(&rq->donelist);
rq->errors = 0;
rq->rq_status = RQ_ACTIVE;
......@@ -285,6 +297,7 @@ static inline void rq_init(request_queue_t *q, struct request *rq)
rq->sense = NULL;
rq->end_io = NULL;
rq->end_io_data = NULL;
rq->completion_data = NULL;
}
/**
......@@ -3261,6 +3274,87 @@ int end_that_request_chunk(struct request *req, int uptodate, int nr_bytes)
EXPORT_SYMBOL(end_that_request_chunk);
/*
* splice the completion data to a local structure and hand off to
* process_completion_queue() to complete the requests
*/
static void blk_done_softirq(struct softirq_action *h)
{
struct list_head *cpu_list;
LIST_HEAD(local_list);
local_irq_disable();
cpu_list = &__get_cpu_var(blk_cpu_done);
list_splice_init(cpu_list, &local_list);
local_irq_enable();
while (!list_empty(&local_list)) {
struct request *rq = list_entry(local_list.next, struct request, donelist);
list_del_init(&rq->donelist);
rq->q->softirq_done_fn(rq);
}
}
#ifdef CONFIG_HOTPLUG_CPU
static int blk_cpu_notify(struct notifier_block *self, unsigned long action,
void *hcpu)
{
/*
* If a CPU goes away, splice its entries to the current CPU
* and trigger a run of the softirq
*/
if (action == CPU_DEAD) {
int cpu = (unsigned long) hcpu;
local_irq_disable();
list_splice_init(&per_cpu(blk_cpu_done, cpu),
&__get_cpu_var(blk_cpu_done));
raise_softirq_irqoff(BLOCK_SOFTIRQ);
local_irq_enable();
}
return NOTIFY_OK;
}
static struct notifier_block __devinitdata blk_cpu_notifier = {
.notifier_call = blk_cpu_notify,
};
#endif /* CONFIG_HOTPLUG_CPU */
/**
* blk_complete_request - end I/O on a request
* @req: the request being processed
*
* Description:
* Ends all I/O on a request. It does not handle partial completions,
* unless the driver actually implements this in its completionc callback
* through requeueing. Theh actual completion happens out-of-order,
* through a softirq handler. The user must have registered a completion
* callback through blk_queue_softirq_done().
**/
void blk_complete_request(struct request *req)
{
struct list_head *cpu_list;
unsigned long flags;
BUG_ON(!req->q->softirq_done_fn);
local_irq_save(flags);
cpu_list = &__get_cpu_var(blk_cpu_done);
list_add_tail(&req->donelist, cpu_list);
raise_softirq_irqoff(BLOCK_SOFTIRQ);
local_irq_restore(flags);
}
EXPORT_SYMBOL(blk_complete_request);
/*
* queue lock must be held
*/
......@@ -3339,6 +3433,8 @@ EXPORT_SYMBOL(kblockd_flush);
int __init blk_dev_init(void)
{
int i;
kblockd_workqueue = create_workqueue("kblockd");
if (!kblockd_workqueue)
panic("Failed to create kblockd\n");
......@@ -3352,6 +3448,14 @@ int __init blk_dev_init(void)
iocontext_cachep = kmem_cache_create("blkdev_ioc",
sizeof(struct io_context), 0, SLAB_PANIC, NULL, NULL);
for (i = 0; i < NR_CPUS; i++)
INIT_LIST_HEAD(&per_cpu(blk_cpu_done, i));
open_softirq(BLOCK_SOFTIRQ, blk_done_softirq, NULL);
#ifdef CONFIG_HOTPLUG_CPU
register_cpu_notifier(&blk_cpu_notifier);
#endif
blk_max_low_pfn = max_low_pfn;
blk_max_pfn = max_pfn;
......
......@@ -2178,16 +2178,48 @@ static inline void resend_cciss_cmd( ctlr_info_t *h, CommandList_struct *c)
start_io(h);
}
static void cciss_softirq_done(struct request *rq)
{
CommandList_struct *cmd = rq->completion_data;
ctlr_info_t *h = hba[cmd->ctlr];
u64bit temp64;
int i, ddir;
if (cmd->Request.Type.Direction == XFER_READ)
ddir = PCI_DMA_FROMDEVICE;
else
ddir = PCI_DMA_TODEVICE;
/* command did not need to be retried */
/* unmap the DMA mapping for all the scatter gather elements */
for(i=0; i<cmd->Header.SGList; i++) {
temp64.val32.lower = cmd->SG[i].Addr.lower;
temp64.val32.upper = cmd->SG[i].Addr.upper;
pci_unmap_page(h->pdev, temp64.val, cmd->SG[i].Len, ddir);
}
complete_buffers(rq->bio, rq->errors);
#ifdef CCISS_DEBUG
printk("Done with %p\n", rq);
#endif /* CCISS_DEBUG */
spin_lock_irq(&h->lock);
end_that_request_last(rq, rq->errors);
cmd_free(h, cmd,1);
spin_unlock_irq(&h->lock);
}
/* checks the status of the job and calls complete buffers to mark all
* buffers for the completed job.
* buffers for the completed job. Note that this function does not need
* to hold the hba/queue lock.
*/
static inline void complete_command( ctlr_info_t *h, CommandList_struct *cmd,
int timeout)
{
int status = 1;
int i;
int retry_cmd = 0;
u64bit temp64;
if (timeout)
status = 0;
......@@ -2295,24 +2327,10 @@ static inline void complete_command( ctlr_info_t *h, CommandList_struct *cmd,
resend_cciss_cmd(h,cmd);
return;
}
/* command did not need to be retried */
/* unmap the DMA mapping for all the scatter gather elements */
for(i=0; i<cmd->Header.SGList; i++) {
temp64.val32.lower = cmd->SG[i].Addr.lower;
temp64.val32.upper = cmd->SG[i].Addr.upper;
pci_unmap_page(hba[cmd->ctlr]->pdev,
temp64.val, cmd->SG[i].Len,
(cmd->Request.Type.Direction == XFER_READ) ?
PCI_DMA_FROMDEVICE : PCI_DMA_TODEVICE);
}
complete_buffers(cmd->rq->bio, status);
#ifdef CCISS_DEBUG
printk("Done with %p\n", cmd->rq);
#endif /* CCISS_DEBUG */
end_that_request_last(cmd->rq, status ? 1 : -EIO);
cmd_free(h,cmd,1);
cmd->rq->completion_data = cmd;
cmd->rq->errors = status;
blk_complete_request(cmd->rq);
}
/*
......@@ -3199,15 +3217,17 @@ static int __devinit cciss_init_one(struct pci_dev *pdev,
drv->queue = q;
q->backing_dev_info.ra_pages = READ_AHEAD;
blk_queue_bounce_limit(q, hba[i]->pdev->dma_mask);
blk_queue_bounce_limit(q, hba[i]->pdev->dma_mask);
/* This is a hardware imposed limit. */
blk_queue_max_hw_segments(q, MAXSGENTRIES);
/* This is a hardware imposed limit. */
blk_queue_max_hw_segments(q, MAXSGENTRIES);
/* This is a limit in the driver and could be eliminated. */
blk_queue_max_phys_segments(q, MAXSGENTRIES);
/* This is a limit in the driver and could be eliminated. */
blk_queue_max_phys_segments(q, MAXSGENTRIES);
blk_queue_max_sectors(q, 512);
blk_queue_max_sectors(q, 512);
blk_queue_softirq_done(q, cciss_softirq_done);
q->queuedata = hba[i];
sprintf(disk->disk_name, "cciss/c%dd%d", i, j);
......
......@@ -55,9 +55,22 @@
#include <asm/io.h>
#include <asm/bitops.h>
void ide_softirq_done(struct request *rq)
{
request_queue_t *q = rq->q;
add_disk_randomness(rq->rq_disk);
end_that_request_chunk(rq, rq->errors, rq->data_len);
spin_lock_irq(q->queue_lock);
end_that_request_last(rq, rq->errors);
spin_unlock_irq(q->queue_lock);
}
int __ide_end_request(ide_drive_t *drive, struct request *rq, int uptodate,
int nr_sectors)
{
unsigned int nbytes;
int ret = 1;
BUG_ON(!(rq->flags & REQ_STARTED));
......@@ -81,17 +94,28 @@ int __ide_end_request(ide_drive_t *drive, struct request *rq, int uptodate,
HWGROUP(drive)->hwif->ide_dma_on(drive);
}
if (!end_that_request_first(rq, uptodate, nr_sectors)) {
add_disk_randomness(rq->rq_disk);
if (blk_rq_tagged(rq))
blk_queue_end_tag(drive->queue, rq);
/*
* For partial completions (or non fs/pc requests), use the regular
* direct completion path.
*/
nbytes = nr_sectors << 9;
if (rq_all_done(rq, nbytes)) {
rq->errors = uptodate;
rq->data_len = nbytes;
blkdev_dequeue_request(rq);
HWGROUP(drive)->rq = NULL;
end_that_request_last(rq, uptodate);
blk_complete_request(rq);
ret = 0;
} else {
if (!end_that_request_first(rq, uptodate, nr_sectors)) {
add_disk_randomness(rq->rq_disk);
blkdev_dequeue_request(rq);
HWGROUP(drive)->rq = NULL;
end_that_request_last(rq, uptodate);
ret = 0;
}
}
return ret;
}
EXPORT_SYMBOL(__ide_end_request);
......@@ -113,6 +137,10 @@ int ide_end_request (ide_drive_t *drive, int uptodate, int nr_sectors)
unsigned long flags;
int ret = 1;
/*
* room for locking improvements here, the calls below don't
* need the queue lock held at all
*/
spin_lock_irqsave(&ide_lock, flags);
rq = HWGROUP(drive)->rq;
......
......@@ -1011,6 +1011,8 @@ static int ide_init_queue(ide_drive_t *drive)
blk_queue_max_hw_segments(q, max_sg_entries);
blk_queue_max_phys_segments(q, max_sg_entries);
blk_queue_softirq_done(q, ide_softirq_done);
/* assign drive queue */
drive->queue = q;
......
......@@ -69,7 +69,6 @@
#include "scsi_logging.h"
static void scsi_done(struct scsi_cmnd *cmd);
static int scsi_retry_command(struct scsi_cmnd *cmd);
/*
* Definitions and constants.
......@@ -752,7 +751,7 @@ static void scsi_done(struct scsi_cmnd *cmd)
* isn't running --- used by scsi_times_out */
void __scsi_done(struct scsi_cmnd *cmd)
{
unsigned long flags;
struct request *rq = cmd->request;
/*
* Set the serial numbers back to zero
......@@ -763,71 +762,14 @@ void __scsi_done(struct scsi_cmnd *cmd)
if (cmd->result)
atomic_inc(&cmd->device->ioerr_cnt);
BUG_ON(!rq);
/*
* Next, enqueue the command into the done queue.
* It is a per-CPU queue, so we just disable local interrupts
* and need no spinlock.
* The uptodate/nbytes values don't matter, as we allow partial
* completes and thus will check this in the softirq callback
*/
local_irq_save(flags);
list_add_tail(&cmd->eh_entry, &__get_cpu_var(scsi_done_q));
raise_softirq_irqoff(SCSI_SOFTIRQ);
local_irq_restore(flags);
}
/**
* scsi_softirq - Perform post-interrupt processing of finished SCSI commands.
*
* This is the consumer of the done queue.
*
* This is called with all interrupts enabled. This should reduce
* interrupt latency, stack depth, and reentrancy of the low-level
* drivers.
*/
static void scsi_softirq(struct softirq_action *h)
{
int disposition;
LIST_HEAD(local_q);
local_irq_disable();
list_splice_init(&__get_cpu_var(scsi_done_q), &local_q);
local_irq_enable();
while (!list_empty(&local_q)) {
struct scsi_cmnd *cmd = list_entry(local_q.next,
struct scsi_cmnd, eh_entry);
/* The longest time any command should be outstanding is the
* per command timeout multiplied by the number of retries.
*
* For a typical command, this is 2.5 minutes */
unsigned long wait_for
= cmd->allowed * cmd->timeout_per_command;
list_del_init(&cmd->eh_entry);
disposition = scsi_decide_disposition(cmd);
if (disposition != SUCCESS &&
time_before(cmd->jiffies_at_alloc + wait_for, jiffies)) {
sdev_printk(KERN_ERR, cmd->device,
"timing out command, waited %lus\n",
wait_for/HZ);
disposition = SUCCESS;
}
scsi_log_completion(cmd, disposition);
switch (disposition) {
case SUCCESS:
scsi_finish_command(cmd);
break;
case NEEDS_RETRY:
scsi_retry_command(cmd);
break;
case ADD_TO_MLQUEUE:
scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY);
break;
default:
if (!scsi_eh_scmd_add(cmd, 0))
scsi_finish_command(cmd);
}
}
rq->completion_data = cmd;
blk_complete_request(rq);
}
/*
......@@ -840,7 +782,7 @@ static void scsi_softirq(struct softirq_action *h)
* level drivers should not become re-entrant as a result of
* this.
*/
static int scsi_retry_command(struct scsi_cmnd *cmd)
int scsi_retry_command(struct scsi_cmnd *cmd)
{
/*
* Restore the SCSI command state.
......@@ -1273,38 +1215,6 @@ int scsi_device_cancel(struct scsi_device *sdev, int recovery)
}
EXPORT_SYMBOL(scsi_device_cancel);
#ifdef CONFIG_HOTPLUG_CPU
static int scsi_cpu_notify(struct notifier_block *self,
unsigned long action, void *hcpu)
{
int cpu = (unsigned long)hcpu;
switch(action) {
case CPU_DEAD:
/* Drain scsi_done_q. */
local_irq_disable();
list_splice_init(&per_cpu(scsi_done_q, cpu),
&__get_cpu_var(scsi_done_q));
raise_softirq_irqoff(SCSI_SOFTIRQ);
local_irq_enable();
break;
default:
break;
}
return NOTIFY_OK;
}
static struct notifier_block __devinitdata scsi_cpu_nb = {
.notifier_call = scsi_cpu_notify,
};
#define register_scsi_cpu() register_cpu_notifier(&scsi_cpu_nb)
#define unregister_scsi_cpu() unregister_cpu_notifier(&scsi_cpu_nb)
#else
#define register_scsi_cpu()
#define unregister_scsi_cpu()
#endif /* CONFIG_HOTPLUG_CPU */
MODULE_DESCRIPTION("SCSI core");
MODULE_LICENSE("GPL");
......@@ -1338,8 +1248,6 @@ static int __init init_scsi(void)
INIT_LIST_HEAD(&per_cpu(scsi_done_q, i));
devfs_mk_dir("scsi");
open_softirq(SCSI_SOFTIRQ, scsi_softirq, NULL);
register_scsi_cpu();
printk(KERN_NOTICE "SCSI subsystem initialized\n");
return 0;
......@@ -1367,7 +1275,6 @@ static void __exit exit_scsi(void)
devfs_remove("scsi");
scsi_exit_procfs();
scsi_exit_queue();
unregister_scsi_cpu();
}
subsys_initcall(init_scsi);
......
......@@ -1493,6 +1493,41 @@ static void scsi_kill_request(struct request *req, request_queue_t *q)
__scsi_done(cmd);
}
static void scsi_softirq_done(struct request *rq)
{
struct scsi_cmnd *cmd = rq->completion_data;
unsigned long wait_for = cmd->allowed * cmd->timeout_per_command;
int disposition;
INIT_LIST_HEAD(&cmd->eh_entry);
disposition = scsi_decide_disposition(cmd);
if (disposition != SUCCESS &&
time_before(cmd->jiffies_at_alloc + wait_for, jiffies)) {
sdev_printk(KERN_ERR, cmd->device,
"timing out command, waited %lus\n",
wait_for/HZ);
disposition = SUCCESS;
}
scsi_log_completion(cmd, disposition);
switch (disposition) {
case SUCCESS:
scsi_finish_command(cmd);
break;
case NEEDS_RETRY:
scsi_retry_command(cmd);
break;
case ADD_TO_MLQUEUE:
scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY);
break;
default:
if (!scsi_eh_scmd_add(cmd, 0))
scsi_finish_command(cmd);
}
}
/*
* Function: scsi_request_fn()
*
......@@ -1667,6 +1702,7 @@ struct request_queue *scsi_alloc_queue(struct scsi_device *sdev)
blk_queue_bounce_limit(q, scsi_calculate_bounce_limit(shost));
blk_queue_segment_boundary(q, shost->dma_boundary);
blk_queue_issue_flush_fn(q, scsi_issue_flush_fn);
blk_queue_softirq_done(q, scsi_softirq_done);
if (!shost->use_clustering)
clear_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags);
......
......@@ -44,6 +44,7 @@ extern void scsi_init_cmd_from_req(struct scsi_cmnd *cmd,
struct scsi_request *sreq);
extern void __scsi_release_request(struct scsi_request *sreq);
extern void __scsi_done(struct scsi_cmnd *cmd);
extern int scsi_retry_command(struct scsi_cmnd *cmd);
#ifdef CONFIG_SCSI_LOGGING
void scsi_log_send(struct scsi_cmnd *cmd);
void scsi_log_completion(struct scsi_cmnd *cmd, int disposition);
......
......@@ -118,9 +118,9 @@ struct request_list {
* try to put the fields that are referenced together in the same cacheline
*/
struct request {
struct list_head queuelist; /* looking for ->queue? you must _not_
* access it directly, use
* blkdev_dequeue_request! */
struct list_head queuelist;
struct list_head donelist;
unsigned long flags; /* see REQ_ bits below */
/* Maintain bio traversal state for part by part I/O submission.
......@@ -141,6 +141,7 @@ struct request {
struct bio *biotail;
void *elevator_private;
void *completion_data;
unsigned short ioprio;
......@@ -291,6 +292,7 @@ typedef int (merge_bvec_fn) (request_queue_t *, struct bio *, struct bio_vec *);
typedef void (activity_fn) (void *data, int rw);
typedef int (issue_flush_fn) (request_queue_t *, struct gendisk *, sector_t *);
typedef void (prepare_flush_fn) (request_queue_t *, struct request *);
typedef void (softirq_done_fn)(struct request *);
enum blk_queue_state {
Queue_down,
......@@ -332,6 +334,7 @@ struct request_queue
activity_fn *activity_fn;
issue_flush_fn *issue_flush_fn;
prepare_flush_fn *prepare_flush_fn;
softirq_done_fn *softirq_done_fn;
/*
* Dispatch queue sorting
......@@ -645,6 +648,17 @@ extern int end_that_request_first(struct request *, int, int);
extern int end_that_request_chunk(struct request *, int, int);
extern void end_that_request_last(struct request *, int);
extern void end_request(struct request *req, int uptodate);
extern void blk_complete_request(struct request *);
static inline int rq_all_done(struct request *rq, unsigned int nr_bytes)
{
if (blk_fs_request(rq))
return (nr_bytes >= (rq->hard_nr_sectors << 9));
else if (blk_pc_request(rq))
return nr_bytes >= rq->data_len;
return 0;
}
/*
* end_that_request_first/chunk() takes an uptodate argument. we account
......@@ -693,6 +707,7 @@ extern void blk_queue_segment_boundary(request_queue_t *, unsigned long);
extern void blk_queue_prep_rq(request_queue_t *, prep_rq_fn *pfn);
extern void blk_queue_merge_bvec(request_queue_t *, merge_bvec_fn *);
extern void blk_queue_dma_alignment(request_queue_t *, int);
extern void blk_queue_softirq_done(request_queue_t *, softirq_done_fn *);
extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
extern int blk_queue_ordered(request_queue_t *, unsigned, prepare_flush_fn *);
extern void blk_queue_issue_flush_fn(request_queue_t *, issue_flush_fn *);
......
......@@ -1001,6 +1001,7 @@ extern int noautodma;
extern int ide_end_request (ide_drive_t *drive, int uptodate, int nrsecs);
extern int __ide_end_request (ide_drive_t *drive, struct request *rq, int uptodate, int nrsecs);
extern void ide_softirq_done(struct request *rq);