staging: erofs: simplify `z_erofs_vle_submit_all'

Previously, there are too many hacked stuffs such as `__FSIO_1',
`lstgrp_noio', `lstgrp_io' out there in `z_erofs_vle_submit_all'.

Revisit the whole process by properly introducing jobqueue to
represent each type of queued workgroups, furthermore hide all of
crazyness behind independent separated functions.

After this patch, 2 independent jobqueues exist if managed cache
is enabled, or 1 jobqueue if disabled.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Gao Xiang 2018-12-08 00:19:18 +08:00 коммит произвёл Greg Kroah-Hartman
Родитель 6afd227ca1
Коммит 7146a4f026
1 изменённых файлов: 113 добавлений и 82 удалений

Просмотреть файл

@ -1229,33 +1229,28 @@ out: /* the only exit (for tracing and debugging) */
return page;
}
static inline struct z_erofs_vle_unzip_io *
prepare_io_handler(struct super_block *sb,
static struct z_erofs_vle_unzip_io *
jobqueue_init(struct super_block *sb,
struct z_erofs_vle_unzip_io *io,
bool background)
bool foreground)
{
struct z_erofs_vle_unzip_io_sb *iosb;
if (!background) {
if (foreground) {
/* waitqueue available for foreground io */
BUG_ON(!io);
DBG_BUGON(!io);
init_waitqueue_head(&io->u.wait);
atomic_set(&io->pending_bios, 0);
goto out;
}
if (io)
BUG();
else {
/* allocate extra io descriptor for background io */
iosb = kvzalloc(sizeof(struct z_erofs_vle_unzip_io_sb),
GFP_KERNEL | __GFP_NOFAIL);
BUG_ON(!iosb);
DBG_BUGON(!iosb);
/* initialize fields in the allocated descriptor */
io = &iosb->io;
}
iosb->sb = sb;
INIT_WORK(&io->u.work, z_erofs_vle_unzip_wq);
out:
@ -1263,27 +1258,105 @@ out:
return io;
}
/* define workgroup jobqueue types */
enum {
#ifdef EROFS_FS_HAS_MANAGED_CACHE
#define __FSIO_1 1
JQ_BYPASS,
#endif
JQ_SUBMIT,
NR_JOBQUEUES,
};
static void *jobqueueset_init(struct super_block *sb,
z_erofs_vle_owned_workgrp_t qtail[],
struct z_erofs_vle_unzip_io *q[],
struct z_erofs_vle_unzip_io *fgq,
bool forcefg)
{
#ifdef EROFS_FS_HAS_MANAGED_CACHE
/*
* if managed cache is enabled, bypass jobqueue is needed,
* no need to read from device for all workgroups in this queue.
*/
q[JQ_BYPASS] = jobqueue_init(sb, fgq + JQ_BYPASS, true);
qtail[JQ_BYPASS] = &q[JQ_BYPASS]->head;
#endif
q[JQ_SUBMIT] = jobqueue_init(sb, fgq + JQ_SUBMIT, forcefg);
qtail[JQ_SUBMIT] = &q[JQ_SUBMIT]->head;
return tagptr_cast_ptr(tagptr_fold(tagptr1_t, q[JQ_SUBMIT], !forcefg));
}
#ifdef EROFS_FS_HAS_MANAGED_CACHE
static void move_to_bypass_jobqueue(struct z_erofs_vle_workgroup *grp,
z_erofs_vle_owned_workgrp_t qtail[],
z_erofs_vle_owned_workgrp_t owned_head)
{
z_erofs_vle_owned_workgrp_t *const submit_qtail = qtail[JQ_SUBMIT];
z_erofs_vle_owned_workgrp_t *const bypass_qtail = qtail[JQ_BYPASS];
DBG_BUGON(owned_head == Z_EROFS_VLE_WORKGRP_TAIL_CLOSED);
if (owned_head == Z_EROFS_VLE_WORKGRP_TAIL)
owned_head = Z_EROFS_VLE_WORKGRP_TAIL_CLOSED;
WRITE_ONCE(grp->next, Z_EROFS_VLE_WORKGRP_TAIL_CLOSED);
WRITE_ONCE(*submit_qtail, owned_head);
WRITE_ONCE(*bypass_qtail, &grp->next);
qtail[JQ_BYPASS] = &grp->next;
}
static bool postsubmit_is_all_bypassed(struct z_erofs_vle_unzip_io *q[],
unsigned int nr_bios,
bool force_fg)
{
/*
* although background is preferred, no one is pending for submission.
* don't issue workqueue for decompression but drop it directly instead.
*/
if (force_fg || nr_bios)
return false;
kvfree(container_of(q[JQ_SUBMIT],
struct z_erofs_vle_unzip_io_sb,
io));
return true;
}
#else
#define __FSIO_1 0
static void move_to_bypass_jobqueue(struct z_erofs_vle_workgroup *grp,
z_erofs_vle_owned_workgrp_t qtail[],
z_erofs_vle_owned_workgrp_t owned_head)
{
/* impossible to bypass submission for managed cache disabled */
DBG_BUGON(1);
}
static bool postsubmit_is_all_bypassed(struct z_erofs_vle_unzip_io *q[],
unsigned int nr_bios,
bool force_fg)
{
/* bios should be >0 if managed cache is disabled */
DBG_BUGON(!nr_bios);
return false;
}
#endif
static bool z_erofs_vle_submit_all(struct super_block *sb,
z_erofs_vle_owned_workgrp_t owned_head,
struct list_head *pagepool,
struct z_erofs_vle_unzip_io *fg_io,
struct z_erofs_vle_unzip_io *fgq,
bool force_fg)
{
struct erofs_sb_info *const sbi = EROFS_SB(sb);
const unsigned int clusterpages = erofs_clusterpages(sbi);
const gfp_t gfp = GFP_NOFS;
#ifdef EROFS_FS_HAS_MANAGED_CACHE
struct z_erofs_vle_workgroup *lstgrp_noio = NULL, *lstgrp_io = NULL;
#endif
struct z_erofs_vle_unzip_io *ios[1 + __FSIO_1];
z_erofs_vle_owned_workgrp_t qtail[NR_JOBQUEUES];
struct z_erofs_vle_unzip_io *q[NR_JOBQUEUES];
struct bio *bio;
tagptr1_t bi_private;
void *bi_private;
/* since bio will be NULL, no need to initialize last_index */
pgoff_t uninitialized_var(last_index);
bool force_submit = false;
@ -1292,28 +1365,13 @@ static bool z_erofs_vle_submit_all(struct super_block *sb,
if (unlikely(owned_head == Z_EROFS_VLE_WORKGRP_TAIL))
return false;
/*
* force_fg == 1, (io, fg_io[0]) no io, (io, fg_io[1]) need submit io
* force_fg == 0, (io, fg_io[0]) no io; (io[1], bg_io) need submit io
*/
#ifdef EROFS_FS_HAS_MANAGED_CACHE
ios[0] = prepare_io_handler(sb, fg_io + 0, false);
#endif
if (force_fg) {
ios[__FSIO_1] = prepare_io_handler(sb, fg_io + __FSIO_1, false);
bi_private = tagptr_fold(tagptr1_t, ios[__FSIO_1], 0);
} else {
ios[__FSIO_1] = prepare_io_handler(sb, NULL, true);
bi_private = tagptr_fold(tagptr1_t, ios[__FSIO_1], 1);
}
nr_bios = 0;
force_submit = false;
bio = NULL;
nr_bios = 0;
bi_private = jobqueueset_init(sb, qtail, q, fgq, force_fg);
/* by default, all need io submission */
ios[__FSIO_1]->head = owned_head;
q[JQ_SUBMIT]->head = owned_head;
do {
struct z_erofs_vle_workgroup *grp;
@ -1353,8 +1411,9 @@ submit_bio_retry:
if (!bio) {
bio = erofs_grab_bio(sb, first_index + i,
BIO_MAX_PAGES, z_erofs_vle_read_endio, true);
bio->bi_private = tagptr_cast_ptr(bi_private);
BIO_MAX_PAGES,
z_erofs_vle_read_endio, true);
bio->bi_private = bi_private;
++nr_bios;
}
@ -1369,47 +1428,19 @@ skippage:
if (++i < clusterpages)
goto repeat;
#ifdef EROFS_FS_HAS_MANAGED_CACHE
if (bypass < clusterpages) {
lstgrp_io = grp;
} else {
z_erofs_vle_owned_workgrp_t iogrp_next =
owned_head == Z_EROFS_VLE_WORKGRP_TAIL ?
Z_EROFS_VLE_WORKGRP_TAIL_CLOSED :
owned_head;
if (!lstgrp_io)
ios[1]->head = iogrp_next;
if (bypass < clusterpages)
qtail[JQ_SUBMIT] = &grp->next;
else
WRITE_ONCE(lstgrp_io->next, iogrp_next);
if (!lstgrp_noio)
ios[0]->head = &grp->next;
else
WRITE_ONCE(lstgrp_noio->next, grp);
lstgrp_noio = grp;
}
#endif
move_to_bypass_jobqueue(grp, qtail, owned_head);
} while (owned_head != Z_EROFS_VLE_WORKGRP_TAIL);
if (bio)
__submit_bio(bio, REQ_OP_READ, 0);
#ifndef EROFS_FS_HAS_MANAGED_CACHE
BUG_ON(!nr_bios);
#else
if (lstgrp_noio)
WRITE_ONCE(lstgrp_noio->next, Z_EROFS_VLE_WORKGRP_TAIL_CLOSED);
if (!force_fg && !nr_bios) {
kvfree(container_of(ios[1],
struct z_erofs_vle_unzip_io_sb, io));
if (postsubmit_is_all_bypassed(q, nr_bios, force_fg))
return true;
}
#endif
z_erofs_vle_unzip_kickoff(tagptr_cast_ptr(bi_private), nr_bios);
z_erofs_vle_unzip_kickoff(bi_private, nr_bios);
return true;
}
@ -1418,23 +1449,23 @@ static void z_erofs_submit_and_unzip(struct z_erofs_vle_frontend *f,
bool force_fg)
{
struct super_block *sb = f->inode->i_sb;
struct z_erofs_vle_unzip_io io[1 + __FSIO_1];
struct z_erofs_vle_unzip_io io[NR_JOBQUEUES];
if (!z_erofs_vle_submit_all(sb, f->owned_head, pagepool, io, force_fg))
return;
#ifdef EROFS_FS_HAS_MANAGED_CACHE
z_erofs_vle_unzip_all(sb, &io[0], pagepool);
z_erofs_vle_unzip_all(sb, &io[JQ_BYPASS], pagepool);
#endif
if (!force_fg)
return;
/* wait until all bios are completed */
wait_event(io[__FSIO_1].u.wait,
!atomic_read(&io[__FSIO_1].pending_bios));
wait_event(io[JQ_SUBMIT].u.wait,
!atomic_read(&io[JQ_SUBMIT].pending_bios));
/* let's synchronous decompression */
z_erofs_vle_unzip_all(sb, &io[__FSIO_1], pagepool);
z_erofs_vle_unzip_all(sb, &io[JQ_SUBMIT], pagepool);
}
static int z_erofs_vle_normalaccess_readpage(struct file *file,