Re: [PATCH 1/2] erofs: get rid of `struct z_erofs_collector'
From: Gao Xiang
Date: Wed Mar 02 2022 - 00:06:49 EST
Hi Yue,
On Wed, Mar 02, 2022 at 12:22:03PM +0800, Yue Hu wrote:
> Hi Xiang,
>
> On Wed, 2 Mar 2022 03:49:50 +0800
> Gao Xiang <hsiangkao@xxxxxxxxxxxxxxxxx> wrote:
>
> > Avoid `struct z_erofs_collector' since there is another context
> > structure called "struct z_erofs_decompress_frontend".
> >
> > No logic changes.
> >
> > Signed-off-by: Gao Xiang <hsiangkao@xxxxxxxxxxxxxxxxx>
> > ---
> > fs/erofs/zdata.c | 163 ++++++++++++++++++++++-------------------------
> > 1 file changed, 77 insertions(+), 86 deletions(-)
> >
> > diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
> > index 423bc1a61da5..2673fc105861 100644
> > --- a/fs/erofs/zdata.c
> > +++ b/fs/erofs/zdata.c
> > @@ -192,7 +192,10 @@ enum z_erofs_collectmode {
> > COLLECT_PRIMARY_FOLLOWED,
> > };
> >
> > -struct z_erofs_collector {
> > +struct z_erofs_decompress_frontend {
> > + struct inode *const inode;
> > + struct erofs_map_blocks map;
> > +
> > struct z_erofs_pagevec_ctor vector;
> >
> > struct z_erofs_pcluster *pcl, *tailpcl;
> > @@ -202,13 +205,6 @@ struct z_erofs_collector {
> > z_erofs_next_pcluster_t owned_head;
> >
> > enum z_erofs_collectmode mode;
> > -};
> > -
> > -struct z_erofs_decompress_frontend {
> > - struct inode *const inode;
> > -
> > - struct z_erofs_collector clt;
> > - struct erofs_map_blocks map;
> >
> > bool readahead;
> > /* used for applying cache strategy on the fly */
> > @@ -216,30 +212,26 @@ struct z_erofs_decompress_frontend {
> > erofs_off_t headoffset;
> > };
> >
> > -#define COLLECTOR_INIT() { \
> > - .owned_head = Z_EROFS_PCLUSTER_TAIL, \
> > - .mode = COLLECT_PRIMARY_FOLLOWED }
> > -
> > #define DECOMPRESS_FRONTEND_INIT(__i) { \
> > - .inode = __i, .clt = COLLECTOR_INIT(), \
> > - .backmost = true, }
> > + .inode = __i, .owned_head = Z_EROFS_PCLUSTER_TAIL, \
> > + .mode = COLLECT_PRIMARY_FOLLOWED }
> >
> > static struct page *z_pagemap_global[Z_EROFS_VMAP_GLOBAL_PAGES];
> > static DEFINE_MUTEX(z_pagemap_global_lock);
> >
> > -static void preload_compressed_pages(struct z_erofs_collector *clt,
> > +static void preload_compressed_pages(struct z_erofs_decompress_frontend *fe,
> > struct address_space *mc,
> > enum z_erofs_cache_alloctype type,
> > struct page **pagepool)
> > {
> > - struct z_erofs_pcluster *pcl = clt->pcl;
> > + struct z_erofs_pcluster *pcl = fe->pcl;
> > bool standalone = true;
> > gfp_t gfp = (mapping_gfp_mask(mc) & ~__GFP_DIRECT_RECLAIM) |
> > __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN;
> > struct page **pages;
> > pgoff_t index;
> >
> > - if (clt->mode < COLLECT_PRIMARY_FOLLOWED)
> > + if (fe->mode < COLLECT_PRIMARY_FOLLOWED)
> > return;
> >
> > pages = pcl->compressed_pages;
> > @@ -288,7 +280,7 @@ static void preload_compressed_pages(struct z_erofs_collector *clt,
> > * managed cache since it can be moved to the bypass queue instead.
> > */
> > if (standalone)
> > - clt->mode = COLLECT_PRIMARY_FOLLOWED_NOINPLACE;
> > + fe->mode = COLLECT_PRIMARY_FOLLOWED_NOINPLACE;
> > }
> >
> > /* called by erofs_shrinker to get rid of all compressed_pages */
> > @@ -350,47 +342,47 @@ int erofs_try_to_free_cached_page(struct page *page)
> > }
> >
> > /* page_type must be Z_EROFS_PAGE_TYPE_EXCLUSIVE */
> > -static bool z_erofs_try_inplace_io(struct z_erofs_collector *clt,
> > +static bool z_erofs_try_inplace_io(struct z_erofs_decompress_frontend *fe,
> > struct page *page)
> > {
> > - struct z_erofs_pcluster *const pcl = clt->pcl;
> > + struct z_erofs_pcluster *const pcl = fe->pcl;
> >
> > - while (clt->icpage_ptr > pcl->compressed_pages)
> > - if (!cmpxchg(--clt->icpage_ptr, NULL, page))
> > + while (fe->icpage_ptr > pcl->compressed_pages)
> > + if (!cmpxchg(--fe->icpage_ptr, NULL, page))
> > return true;
> > return false;
> > }
> >
> > /* callers must be with collection lock held */
> > -static int z_erofs_attach_page(struct z_erofs_collector *clt,
> > +static int z_erofs_attach_page(struct z_erofs_decompress_frontend *fe,
> > struct page *page, enum z_erofs_page_type type,
> > bool pvec_safereuse)
> > {
> > int ret;
> >
> > /* give priority for inplaceio */
> > - if (clt->mode >= COLLECT_PRIMARY &&
> > + if (fe->mode >= COLLECT_PRIMARY &&
> > type == Z_EROFS_PAGE_TYPE_EXCLUSIVE &&
> > - z_erofs_try_inplace_io(clt, page))
> > + z_erofs_try_inplace_io(fe, page))
> > return 0;
> >
> > - ret = z_erofs_pagevec_enqueue(&clt->vector, page, type,
> > + ret = z_erofs_pagevec_enqueue(&fe->vector, page, type,
> > pvec_safereuse);
> > - clt->cl->vcnt += (unsigned int)ret;
> > + fe->cl->vcnt += (unsigned int)ret;
> > return ret ? 0 : -EAGAIN;
> > }
> >
> > -static void z_erofs_try_to_claim_pcluster(struct z_erofs_collector *clt)
> > +static void z_erofs_try_to_claim_pcluster(struct z_erofs_decompress_frontend *f)
> > {
> > - struct z_erofs_pcluster *pcl = clt->pcl;
> > - z_erofs_next_pcluster_t *owned_head = &clt->owned_head;
> > + struct z_erofs_pcluster *pcl = f->pcl;
> > + z_erofs_next_pcluster_t *owned_head = &f->owned_head;
> >
> > /* type 1, nil pcluster (this pcluster doesn't belong to any chain.) */
> > if (cmpxchg(&pcl->next, Z_EROFS_PCLUSTER_NIL,
> > *owned_head) == Z_EROFS_PCLUSTER_NIL) {
> > *owned_head = &pcl->next;
> > /* so we can attach this pcluster to our submission chain. */
> > - clt->mode = COLLECT_PRIMARY_FOLLOWED;
> > + f->mode = COLLECT_PRIMARY_FOLLOWED;
> > return;
> > }
> >
> > @@ -401,24 +393,24 @@ static void z_erofs_try_to_claim_pcluster(struct z_erofs_collector *clt)
> > if (cmpxchg(&pcl->next, Z_EROFS_PCLUSTER_TAIL,
> > *owned_head) == Z_EROFS_PCLUSTER_TAIL) {
> > *owned_head = Z_EROFS_PCLUSTER_TAIL;
> > - clt->mode = COLLECT_PRIMARY_HOOKED;
> > - clt->tailpcl = NULL;
> > + f->mode = COLLECT_PRIMARY_HOOKED;
> > + f->tailpcl = NULL;
> > return;
> > }
> > /* type 3, it belongs to a chain, but it isn't the end of the chain */
> > - clt->mode = COLLECT_PRIMARY;
> > + f->mode = COLLECT_PRIMARY;
> > }
> >
> > -static int z_erofs_lookup_collection(struct z_erofs_collector *clt,
> > +static int z_erofs_lookup_collection(struct z_erofs_decompress_frontend *fe,
> > struct inode *inode,
> > struct erofs_map_blocks *map)
> > {
> > - struct z_erofs_pcluster *pcl = clt->pcl;
> > + struct z_erofs_pcluster *pcl = fe->pcl;
> > struct z_erofs_collection *cl;
> > unsigned int length;
> >
> > /* to avoid unexpected loop formed by corrupted images */
> > - if (clt->owned_head == &pcl->next || pcl == clt->tailpcl) {
> > + if (fe->owned_head == &pcl->next || pcl == fe->tailpcl) {
> > DBG_BUGON(1);
> > return -EFSCORRUPTED;
> > }
> > @@ -449,15 +441,15 @@ static int z_erofs_lookup_collection(struct z_erofs_collector *clt,
> > }
> > mutex_lock(&cl->lock);
> > /* used to check tail merging loop due to corrupted images */
> > - if (clt->owned_head == Z_EROFS_PCLUSTER_TAIL)
> > - clt->tailpcl = pcl;
> > + if (fe->owned_head == Z_EROFS_PCLUSTER_TAIL)
> > + fe->tailpcl = pcl;
> >
> > - z_erofs_try_to_claim_pcluster(clt);
> > - clt->cl = cl;
> > + z_erofs_try_to_claim_pcluster(fe);
> > + fe->cl = cl;
> > return 0;
> > }
> >
> > -static int z_erofs_register_collection(struct z_erofs_collector *clt,
> > +static int z_erofs_register_collection(struct z_erofs_decompress_frontend *fe,
> > struct inode *inode,
> > struct erofs_map_blocks *map)
> > {
> > @@ -485,8 +477,8 @@ static int z_erofs_register_collection(struct z_erofs_collector *clt,
> > Z_EROFS_PCLUSTER_FULL_LENGTH : 0);
> >
> > /* new pclusters should be claimed as type 1, primary and followed */
> > - pcl->next = clt->owned_head;
> > - clt->mode = COLLECT_PRIMARY_FOLLOWED;
> > + pcl->next = fe->owned_head;
> > + fe->mode = COLLECT_PRIMARY_FOLLOWED;
> >
> > cl = z_erofs_primarycollection(pcl);
> > cl->pageofs = map->m_la & ~PAGE_MASK;
> > @@ -512,18 +504,18 @@ static int z_erofs_register_collection(struct z_erofs_collector *clt,
> > }
> >
> > if (grp != &pcl->obj) {
> > - clt->pcl = container_of(grp,
> > + fe->pcl = container_of(grp,
> > struct z_erofs_pcluster, obj);
> > err = -EEXIST;
> > goto err_out;
> > }
> > }
> > /* used to check tail merging loop due to corrupted images */
> > - if (clt->owned_head == Z_EROFS_PCLUSTER_TAIL)
> > - clt->tailpcl = pcl;
> > - clt->owned_head = &pcl->next;
> > - clt->pcl = pcl;
> > - clt->cl = cl;
> > + if (fe->owned_head == Z_EROFS_PCLUSTER_TAIL)
> > + fe->tailpcl = pcl;
> > + fe->owned_head = &pcl->next;
> > + fe->pcl = pcl;
> > + fe->cl = cl;
> > return 0;
> >
> > err_out:
> > @@ -532,18 +524,18 @@ static int z_erofs_register_collection(struct z_erofs_collector *clt,
> > return err;
> > }
> >
> > -static int z_erofs_collector_begin(struct z_erofs_collector *clt,
> > +static int z_erofs_collector_begin(struct z_erofs_decompress_frontend *fe,
> > struct inode *inode,
> > struct erofs_map_blocks *map)
> > {
> > struct erofs_workgroup *grp;
> > int ret;
> >
> > - DBG_BUGON(clt->cl);
> > + DBG_BUGON(fe->cl);
> >
> > /* must be Z_EROFS_PCLUSTER_TAIL or pointed to previous collection */
> > - DBG_BUGON(clt->owned_head == Z_EROFS_PCLUSTER_NIL);
> > - DBG_BUGON(clt->owned_head == Z_EROFS_PCLUSTER_TAIL_CLOSED);
> > + DBG_BUGON(fe->owned_head == Z_EROFS_PCLUSTER_NIL);
> > + DBG_BUGON(fe->owned_head == Z_EROFS_PCLUSTER_TAIL_CLOSED);
> >
> > if (map->m_flags & EROFS_MAP_META) {
> > if ((map->m_pa & ~PAGE_MASK) + map->m_plen > PAGE_SIZE) {
> > @@ -555,28 +547,28 @@ static int z_erofs_collector_begin(struct z_erofs_collector *clt,
> >
> > grp = erofs_find_workgroup(inode->i_sb, map->m_pa >> PAGE_SHIFT);
> > if (grp) {
> > - clt->pcl = container_of(grp, struct z_erofs_pcluster, obj);
> > + fe->pcl = container_of(grp, struct z_erofs_pcluster, obj);
> > } else {
> > tailpacking:
> > - ret = z_erofs_register_collection(clt, inode, map);
> > + ret = z_erofs_register_collection(fe, inode, map);
> > if (!ret)
> > goto out;
> > if (ret != -EEXIST)
> > return ret;
> > }
> >
> > - ret = z_erofs_lookup_collection(clt, inode, map);
> > + ret = z_erofs_lookup_collection(fe, inode, map);
> > if (ret) {
> > - erofs_workgroup_put(&clt->pcl->obj);
> > + erofs_workgroup_put(&fe->pcl->obj);
> > return ret;
> > }
> >
> > out:
> > - z_erofs_pagevec_ctor_init(&clt->vector, Z_EROFS_NR_INLINE_PAGEVECS,
> > - clt->cl->pagevec, clt->cl->vcnt);
> > + z_erofs_pagevec_ctor_init(&fe->vector, Z_EROFS_NR_INLINE_PAGEVECS,
> > + fe->cl->pagevec, fe->cl->vcnt);
> > /* since file-backed online pages are traversed in reverse order */
> > - clt->icpage_ptr = clt->pcl->compressed_pages +
> > - z_erofs_pclusterpages(clt->pcl);
> > + fe->icpage_ptr = fe->pcl->compressed_pages +
> > + z_erofs_pclusterpages(fe->pcl);
> > return 0;
> > }
> >
> > @@ -610,24 +602,24 @@ static void z_erofs_collection_put(struct z_erofs_collection *cl)
> > erofs_workgroup_put(&pcl->obj);
> > }
> >
> > -static bool z_erofs_collector_end(struct z_erofs_collector *clt)
> > +static bool z_erofs_collector_end(struct z_erofs_decompress_frontend *fe)
> > {
> > - struct z_erofs_collection *cl = clt->cl;
> > + struct z_erofs_collection *cl = fe->cl;
> >
> > if (!cl)
> > return false;
> >
> > - z_erofs_pagevec_ctor_exit(&clt->vector, false);
> > + z_erofs_pagevec_ctor_exit(&fe->vector, false);
> > mutex_unlock(&cl->lock);
> >
> > /*
> > * if all pending pages are added, don't hold its reference
> > * any longer if the pcluster isn't hosted by ourselves.
> > */
> > - if (clt->mode < COLLECT_PRIMARY_FOLLOWED_NOINPLACE)
> > + if (fe->mode < COLLECT_PRIMARY_FOLLOWED_NOINPLACE)
> > z_erofs_collection_put(cl);
> >
> > - clt->cl = NULL;
> > + fe->cl = NULL;
> > return true;
> > }
> >
> > @@ -651,7 +643,6 @@ static int z_erofs_do_read_page(struct z_erofs_decompress_frontend *fe,
> > struct inode *const inode = fe->inode;
> > struct erofs_sb_info *const sbi = EROFS_I_SB(inode);
> > struct erofs_map_blocks *const map = &fe->map;
> > - struct z_erofs_collector *const clt = &fe->clt;
> > const loff_t offset = page_offset(page);
> > bool tight = true;
> >
> > @@ -672,7 +663,7 @@ static int z_erofs_do_read_page(struct z_erofs_decompress_frontend *fe,
> > if (offset + cur >= map->m_la &&
> > offset + cur < map->m_la + map->m_llen) {
> > /* didn't get a valid collection previously (very rare) */
> > - if (!clt->cl)
> > + if (!fe->cl)
> > goto restart_now;
> > goto hitted;
> > }
> > @@ -680,7 +671,7 @@ static int z_erofs_do_read_page(struct z_erofs_decompress_frontend *fe,
> > /* go ahead the next map_blocks */
> > erofs_dbg("%s: [out-of-range] pos %llu", __func__, offset + cur);
> >
> > - if (z_erofs_collector_end(clt))
> > + if (z_erofs_collector_end(fe))
> > fe->backmost = false;
> >
> > map->m_la = offset + cur;
> > @@ -693,11 +684,11 @@ static int z_erofs_do_read_page(struct z_erofs_decompress_frontend *fe,
> > if (!(map->m_flags & EROFS_MAP_MAPPED))
> > goto hitted;
> >
> > - err = z_erofs_collector_begin(clt, inode, map);
> > + err = z_erofs_collector_begin(fe, inode, map);
>
> now, we can get 'inode' and 'map' from 'fe'. so, it should be z_erofs_collector_begin(fe)?
> if it's, need to change z_erofs_{register | lookup}_collection() correspondingly.
This is just a trivial cleanup (just merge `collector' into `frontend').
We can update them in the following patches. Also I'd like to rename
`collection' concept as well. However, since I'm not a native English
speaker, I didn't find a more proper name though.
Thanks,
Gao Xiang