On Thu, Aug 8, 2024 at 12:01 PM Chris Li <chrisl@xxxxxxxxxx> wrote:
>
> On Wed, Aug 7, 2024 at 2:59 PM Barry Song <21cnbao@xxxxxxxxx> wrote:
> >
> > From: Barry Song <v-songbaohua@xxxxxxxx>
> >
> > "p" means "pointer to something", rename it to a more meaningful
> > identifier - "si".
>
> Hi Berry,
>
> I am fine with the reason for renaming it to something more
> meaningful. On the other hand this will create a huge conflict on the
> next iteration of the swap allocator series. There is not much urgency
> in the renaming variable, right? Just try to figure out a way to
> coordinate it better. As it is, I am not sure how to handle the next
> refresh of swap allocator series, should I revert the rename or submit
> a refresh of patches with rename conflict resolved, effectively foldin
> the rename patch.
right, it is not urgent. if you are going to make another iteration
for the swap allocation series. I am perfect fine that you can add
these two patches into your series? it should be fine as this patchset
obviously depends on Kairui's and Your work.
>
> Chris
>
> > We also have a case with the name "sis", rename it to "si" as
> > well.
> >
> > Signed-off-by: Barry Song <v-songbaohua@xxxxxxxx>
> > Acked-by: David Hildenbrand <david@xxxxxxxxxx>
> > ---
> > mm/swapfile.c | 334 +++++++++++++++++++++++++-------------------------
> > 1 file changed, 167 insertions(+), 167 deletions(-)
> >
> > diff --git a/mm/swapfile.c b/mm/swapfile.c
> > index ea023fc25d08..35cb58373493 100644
> > --- a/mm/swapfile.c
> > +++ b/mm/swapfile.c
> > @@ -532,7 +532,7 @@ static void free_cluster(struct swap_info_struct *si, struct swap_cluster_info *
> > * added to free cluster list and its usage counter will be increased by 1.
> > * Only used for initialization.
> > */
> > -static void inc_cluster_info_page(struct swap_info_struct *p,
> > +static void inc_cluster_info_page(struct swap_info_struct *si,
> > struct swap_cluster_info *cluster_info, unsigned long page_nr)
> > {
> > unsigned long idx = page_nr / SWAPFILE_CLUSTER;
> > @@ -553,28 +553,28 @@ static void inc_cluster_info_page(struct swap_info_struct *p,
> > * which means no page in the cluster is in use, we can optionally discard
> > * the cluster and add it to free cluster list.
> > */
> > -static void dec_cluster_info_page(struct swap_info_struct *p,
> > +static void dec_cluster_info_page(struct swap_info_struct *si,
> > struct swap_cluster_info *ci, int nr_pages)
> > {
> > - if (!p->cluster_info)
> > + if (!si->cluster_info)
> > return;
> >
> > VM_BUG_ON(ci->count < nr_pages);
> > VM_BUG_ON(cluster_is_free(ci));
> > - lockdep_assert_held(&p->lock);
> > + lockdep_assert_held(&si->lock);
> > lockdep_assert_held(&ci->lock);
> > ci->count -= nr_pages;
> >
> > if (!ci->count) {
> > - free_cluster(p, ci);
> > + free_cluster(si, ci);
> > return;
> > }
> >
> > if (!(ci->flags & CLUSTER_FLAG_NONFULL)) {
> > VM_BUG_ON(ci->flags & CLUSTER_FLAG_FREE);
> > if (ci->flags & CLUSTER_FLAG_FRAG)
> > - p->frag_cluster_nr[ci->order]--;
> > - list_move_tail(&ci->list, &p->nonfull_clusters[ci->order]);
> > + si->frag_cluster_nr[ci->order]--;
> > + list_move_tail(&ci->list, &si->nonfull_clusters[ci->order]);
> > ci->flags = CLUSTER_FLAG_NONFULL;
> > }
> > }
> > @@ -872,19 +872,19 @@ static unsigned long cluster_alloc_swap_entry(struct swap_info_struct *si, int o
> > return found;
> > }
> >
> > -static void __del_from_avail_list(struct swap_info_struct *p)
> > +static void __del_from_avail_list(struct swap_info_struct *si)
> > {
> > int nid;
> >
> > - assert_spin_locked(&p->lock);
> > + assert_spin_locked(&si->lock);
> > for_each_node(nid)
> > - plist_del(&p->avail_lists[nid], &swap_avail_heads[nid]);
> > + plist_del(&si->avail_lists[nid], &swap_avail_heads[nid]);
> > }
> >
> > -static void del_from_avail_list(struct swap_info_struct *p)
> > +static void del_from_avail_list(struct swap_info_struct *si)
> > {
> > spin_lock(&swap_avail_lock);
> > - __del_from_avail_list(p);
> > + __del_from_avail_list(si);
> > spin_unlock(&swap_avail_lock);
> > }
> >
> > @@ -905,13 +905,13 @@ static void swap_range_alloc(struct swap_info_struct *si, unsigned long offset,
> > }
> > }
> >
> > -static void add_to_avail_list(struct swap_info_struct *p)
> > +static void add_to_avail_list(struct swap_info_struct *si)
> > {
> > int nid;
> >
> > spin_lock(&swap_avail_lock);
> > for_each_node(nid)
> > - plist_add(&p->avail_lists[nid], &swap_avail_heads[nid]);
> > + plist_add(&si->avail_lists[nid], &swap_avail_heads[nid]);
> > spin_unlock(&swap_avail_lock);
> > }
> >
> > @@ -1291,22 +1291,22 @@ int get_swap_pages(int n_goal, swp_entry_t swp_entries[], int entry_order)
> >
> > static struct swap_info_struct *_swap_info_get(swp_entry_t entry)
> > {
> > - struct swap_info_struct *p;
> > + struct swap_info_struct *si;
> > unsigned long offset;
> >
> > if (!entry.val)
> > goto out;
> > - p = swp_swap_info(entry);
> > - if (!p)
> > + si = swp_swap_info(entry);
> > + if (!si)
> > goto bad_nofile;
> > - if (data_race(!(p->flags & SWP_USED)))
> > + if (data_race(!(si->flags & SWP_USED)))
> > goto bad_device;
> > offset = swp_offset(entry);
> > - if (offset >= p->max)
> > + if (offset >= si->max)
> > goto bad_offset;
> > - if (data_race(!p->swap_map[swp_offset(entry)]))
> > + if (data_race(!si->swap_map[swp_offset(entry)]))
> > goto bad_free;
> > - return p;
> > + return si;
> >
> > bad_free:
> > pr_err("%s: %s%08lx\n", __func__, Unused_offset, entry.val);
> > @@ -1339,14 +1339,14 @@ static struct swap_info_struct *swap_info_get_cont(swp_entry_t entry,
> > return p;
> > }
> >
> > -static unsigned char __swap_entry_free_locked(struct swap_info_struct *p,
> > +static unsigned char __swap_entry_free_locked(struct swap_info_struct *si,
> > unsigned long offset,
> > unsigned char usage)
> > {
> > unsigned char count;
> > unsigned char has_cache;
> >
> > - count = p->swap_map[offset];
> > + count = si->swap_map[offset];
> >
> > has_cache = count & SWAP_HAS_CACHE;
> > count &= ~SWAP_HAS_CACHE;
> > @@ -1362,7 +1362,7 @@ static unsigned char __swap_entry_free_locked(struct swap_info_struct *p,
> > count = 0;
> > } else if ((count & ~COUNT_CONTINUED) <= SWAP_MAP_MAX) {
> > if (count == COUNT_CONTINUED) {
> > - if (swap_count_continued(p, offset, count))
> > + if (swap_count_continued(si, offset, count))
> > count = SWAP_MAP_MAX | COUNT_CONTINUED;
> > else
> > count = SWAP_MAP_MAX;
> > @@ -1372,9 +1372,9 @@ static unsigned char __swap_entry_free_locked(struct swap_info_struct *p,
> >
> > usage = count | has_cache;
> > if (usage)
> > - WRITE_ONCE(p->swap_map[offset], usage);
> > + WRITE_ONCE(si->swap_map[offset], usage);
> > else
> > - WRITE_ONCE(p->swap_map[offset], SWAP_HAS_CACHE);
> > + WRITE_ONCE(si->swap_map[offset], SWAP_HAS_CACHE);
> >
> > return usage;
> > }
> > @@ -1453,16 +1453,16 @@ struct swap_info_struct *get_swap_device(swp_entry_t entry)
> > return NULL;
> > }
> >
> > -static unsigned char __swap_entry_free(struct swap_info_struct *p,
> > +static unsigned char __swap_entry_free(struct swap_info_struct *si,
> > swp_entry_t entry)
> > {
> > struct swap_cluster_info *ci;
> > unsigned long offset = swp_offset(entry);
> > unsigned char usage;
> >
> > - ci = lock_cluster_or_swap_info(p, offset);
> > - usage = __swap_entry_free_locked(p, offset, 1);
> > - unlock_cluster_or_swap_info(p, ci);
> > + ci = lock_cluster_or_swap_info(si, offset);
> > + usage = __swap_entry_free_locked(si, offset, 1);
> > + unlock_cluster_or_swap_info(si, ci);
> > if (!usage)
> > free_swap_slot(entry);
> >
> > @@ -1473,27 +1473,27 @@ static unsigned char __swap_entry_free(struct swap_info_struct *p,
> > * Drop the last HAS_CACHE flag of swap entries, caller have to
> > * ensure all entries belong to the same cgroup.
> > */
> > -static void swap_entry_range_free(struct swap_info_struct *p, swp_entry_t entry,
> > +static void swap_entry_range_free(struct swap_info_struct *si, swp_entry_t entry,
> > unsigned int nr_pages)
> > {
> > unsigned long offset = swp_offset(entry);
> > - unsigned char *map = p->swap_map + offset;
> > + unsigned char *map = si->swap_map + offset;
> > unsigned char *map_end = map + nr_pages;
> > struct swap_cluster_info *ci;
> >
> > - ci = lock_cluster(p, offset);
> > + ci = lock_cluster(si, offset);
> > do {
> > VM_BUG_ON(*map != SWAP_HAS_CACHE);
> > *map = 0;
> > } while (++map < map_end);
> > - dec_cluster_info_page(p, ci, nr_pages);
> > + dec_cluster_info_page(si, ci, nr_pages);
> > unlock_cluster(ci);
> >
> > mem_cgroup_uncharge_swap(entry, nr_pages);
> > - swap_range_free(p, offset, nr_pages);
> > + swap_range_free(si, offset, nr_pages);
> > }
> >
> > -static void cluster_swap_free_nr(struct swap_info_struct *sis,
> > +static void cluster_swap_free_nr(struct swap_info_struct *si,
> > unsigned long offset, int nr_pages,
> > unsigned char usage)
> > {
> > @@ -1501,26 +1501,26 @@ static void cluster_swap_free_nr(struct swap_info_struct *sis,
> > DECLARE_BITMAP(to_free, BITS_PER_LONG) = { 0 };
> > int i, nr;
> >
> > - ci = lock_cluster_or_swap_info(sis, offset);
> > + ci = lock_cluster_or_swap_info(si, offset);
> > while (nr_pages) {
> > nr = min(BITS_PER_LONG, nr_pages);
> > for (i = 0; i < nr; i++) {
> > - if (!__swap_entry_free_locked(sis, offset + i, usage))
> > + if (!__swap_entry_free_locked(si, offset + i, usage))
> > bitmap_set(to_free, i, 1);
> > }
> > if (!bitmap_empty(to_free, BITS_PER_LONG)) {
> > - unlock_cluster_or_swap_info(sis, ci);
> > + unlock_cluster_or_swap_info(si, ci);
> > for_each_set_bit(i, to_free, BITS_PER_LONG)
> > - free_swap_slot(swp_entry(sis->type, offset + i));
> > + free_swap_slot(swp_entry(si->type, offset + i));
> > if (nr == nr_pages)
> > return;
> > bitmap_clear(to_free, 0, BITS_PER_LONG);
> > - ci = lock_cluster_or_swap_info(sis, offset);
> > + ci = lock_cluster_or_swap_info(si, offset);
> > }
> > offset += nr;
> > nr_pages -= nr;
> > }
> > - unlock_cluster_or_swap_info(sis, ci);
> > + unlock_cluster_or_swap_info(si, ci);
> > }
> >
> > /*
> > @@ -1646,28 +1646,28 @@ int swap_swapcount(struct swap_info_struct *si, swp_entry_t entry)
> > int swp_swapcount(swp_entry_t entry)
> > {
> > int count, tmp_count, n;
> > - struct swap_info_struct *p;
> > + struct swap_info_struct *si;
> > struct swap_cluster_info *ci;
> > struct page *page;
> > pgoff_t offset;
> > unsigned char *map;
> >
> > - p = _swap_info_get(entry);
> > - if (!p)
> > + si = _swap_info_get(entry);
> > + if (!si)
> > return 0;
> >
> > offset = swp_offset(entry);
> >
> > - ci = lock_cluster_or_swap_info(p, offset);
> > + ci = lock_cluster_or_swap_info(si, offset);
> >
> > - count = swap_count(p->swap_map[offset]);
> > + count = swap_count(si->swap_map[offset]);
> > if (!(count & COUNT_CONTINUED))
> > goto out;
> >
> > count &= ~COUNT_CONTINUED;
> > n = SWAP_MAP_MAX + 1;
> >
> > - page = vmalloc_to_page(p->swap_map + offset);
> > + page = vmalloc_to_page(si->swap_map + offset);
> > offset &= ~PAGE_MASK;
> > VM_BUG_ON(page_private(page) != SWP_CONTINUED);
> >
> > @@ -1681,7 +1681,7 @@ int swp_swapcount(swp_entry_t entry)
> > n *= (SWAP_CONT_MAX + 1);
> > } while (tmp_count & COUNT_CONTINUED);
> > out:
> > - unlock_cluster_or_swap_info(p, ci);
> > + unlock_cluster_or_swap_info(si, ci);
> > return count;
> > }
> >
> > @@ -2542,52 +2542,52 @@ static int setup_swap_extents(struct swap_info_struct *sis, sector_t *span)
> > return generic_swapfile_activate(sis, swap_file, span);
> > }
> >
> > -static int swap_node(struct swap_info_struct *p)
> > +static int swap_node(struct swap_info_struct *si)
> > {
> > struct block_device *bdev;
> >
> > - if (p->bdev)
> > - bdev = p->bdev;
> > + if (si->bdev)
> > + bdev = si->bdev;
> > else
> > - bdev = p->swap_file->f_inode->i_sb->s_bdev;
> > + bdev = si->swap_file->f_inode->i_sb->s_bdev;
> >
> > return bdev ? bdev->bd_disk->node_id : NUMA_NO_NODE;
> > }
> >
> > -static void setup_swap_info(struct swap_info_struct *p, int prio,
> > +static void setup_swap_info(struct swap_info_struct *si, int prio,
> > unsigned char *swap_map,
> > struct swap_cluster_info *cluster_info)
> > {
> > int i;
> >
> > if (prio >= 0)
> > - p->prio = prio;
> > + si->prio = prio;
> > else
> > - p->prio = --least_priority;
> > + si->prio = --least_priority;
> > /*
> > * the plist prio is negated because plist ordering is
> > * low-to-high, while swap ordering is high-to-low
> > */
> > - p->list.prio = -p->prio;
> > + si->list.prio = -si->prio;
> > for_each_node(i) {
> > - if (p->prio >= 0)
> > - p->avail_lists[i].prio = -p->prio;
> > + if (si->prio >= 0)
> > + si->avail_lists[i].prio = -si->prio;
> > else {
> > - if (swap_node(p) == i)
> > - p->avail_lists[i].prio = 1;
> > + if (swap_node(si) == i)
> > + si->avail_lists[i].prio = 1;
> > else
> > - p->avail_lists[i].prio = -p->prio;
> > + si->avail_lists[i].prio = -si->prio;
> > }
> > }
> > - p->swap_map = swap_map;
> > - p->cluster_info = cluster_info;
> > + si->swap_map = swap_map;
> > + si->cluster_info = cluster_info;
> > }
> >
> > -static void _enable_swap_info(struct swap_info_struct *p)
> > +static void _enable_swap_info(struct swap_info_struct *si)
> > {
> > - p->flags |= SWP_WRITEOK;
> > - atomic_long_add(p->pages, &nr_swap_pages);
> > - total_swap_pages += p->pages;
> > + si->flags |= SWP_WRITEOK;
> > + atomic_long_add(si->pages, &nr_swap_pages);
> > + total_swap_pages += si->pages;
> >
> > assert_spin_locked(&swap_lock);
> > /*
> > @@ -2600,40 +2600,40 @@ static void _enable_swap_info(struct swap_info_struct *p)
> > * which allocates swap pages from the highest available priority
> > * swap_info_struct.
> > */
> > - plist_add(&p->list, &swap_active_head);
> > + plist_add(&si->list, &swap_active_head);
> >
> > /* add to available list iff swap device is not full */
> > - if (p->highest_bit)
> > - add_to_avail_list(p);
> > + if (si->highest_bit)
> > + add_to_avail_list(si);
> > }
> >
> > -static void enable_swap_info(struct swap_info_struct *p, int prio,
> > +static void enable_swap_info(struct swap_info_struct *si, int prio,
> > unsigned char *swap_map,
> > struct swap_cluster_info *cluster_info)
> > {
> > spin_lock(&swap_lock);
> > - spin_lock(&p->lock);
> > - setup_swap_info(p, prio, swap_map, cluster_info);
> > - spin_unlock(&p->lock);
> > + spin_lock(&si->lock);
> > + setup_swap_info(si, prio, swap_map, cluster_info);
> > + spin_unlock(&si->lock);
> > spin_unlock(&swap_lock);
> > /*
> > * Finished initializing swap device, now it's safe to reference it.
> > */
> > - percpu_ref_resurrect(&p->users);
> > + percpu_ref_resurrect(&si->users);
> > spin_lock(&swap_lock);
> > - spin_lock(&p->lock);
> > - _enable_swap_info(p);
> > - spin_unlock(&p->lock);
> > + spin_lock(&si->lock);
> > + _enable_swap_info(si);
> > + spin_unlock(&si->lock);
> > spin_unlock(&swap_lock);
> > }
> >
> > -static void reinsert_swap_info(struct swap_info_struct *p)
> > +static void reinsert_swap_info(struct swap_info_struct *si)
> > {
> > spin_lock(&swap_lock);
> > - spin_lock(&p->lock);
> > - setup_swap_info(p, p->prio, p->swap_map, p->cluster_info);
> > - _enable_swap_info(p);
> > - spin_unlock(&p->lock);
> > + spin_lock(&si->lock);
> > + setup_swap_info(si, si->prio, si->swap_map, si->cluster_info);
> > + _enable_swap_info(si);
> > + spin_unlock(&si->lock);
> > spin_unlock(&swap_lock);
> > }
> >
> > @@ -3019,20 +3019,20 @@ static struct swap_info_struct *alloc_swap_info(void)
> > return p;
> > }
> >
> > -static int claim_swapfile(struct swap_info_struct *p, struct inode *inode)
> > +static int claim_swapfile(struct swap_info_struct *si, struct inode *inode)
> > {
> > if (S_ISBLK(inode->i_mode)) {
> > - p->bdev = I_BDEV(inode);
> > + si->bdev = I_BDEV(inode);
> > /*
> > * Zoned block devices contain zones that have a sequential
> > * write only restriction. Hence zoned block devices are not
> > * suitable for swapping. Disallow them here.
> > */
> > - if (bdev_is_zoned(p->bdev))
> > + if (bdev_is_zoned(si->bdev))
> > return -EINVAL;
> > - p->flags |= SWP_BLKDEV;
> > + si->flags |= SWP_BLKDEV;
> > } else if (S_ISREG(inode->i_mode)) {
> > - p->bdev = inode->i_sb->s_bdev;
> > + si->bdev = inode->i_sb->s_bdev;
> > }
> >
> > return 0;
> > @@ -3067,7 +3067,7 @@ __weak unsigned long arch_max_swapfile_size(void)
> > return generic_max_swapfile_size();
> > }
> >
> > -static unsigned long read_swap_header(struct swap_info_struct *p,
> > +static unsigned long read_swap_header(struct swap_info_struct *si,
> > union swap_header *swap_header,
> > struct inode *inode)
> > {
> > @@ -3098,9 +3098,9 @@ static unsigned long read_swap_header(struct swap_info_struct *p,
> > return 0;
> > }
> >
> > - p->lowest_bit = 1;
> > - p->cluster_next = 1;
> > - p->cluster_nr = 0;
> > + si->lowest_bit = 1;
> > + si->cluster_next = 1;
> > + si->cluster_nr = 0;
> >
> > maxpages = swapfile_maximum_size;
> > last_page = swap_header->info.last_page;
> > @@ -3118,7 +3118,7 @@ static unsigned long read_swap_header(struct swap_info_struct *p,
> > if ((unsigned int)maxpages == 0)
> > maxpages = UINT_MAX;
> > }
> > - p->highest_bit = maxpages - 1;
> > + si->highest_bit = maxpages - 1;
> >
> > if (!maxpages)
> > return 0;
> > @@ -3142,7 +3142,7 @@ static unsigned long read_swap_header(struct swap_info_struct *p,
> > #define SWAP_CLUSTER_COLS \
> > max_t(unsigned int, SWAP_CLUSTER_INFO_COLS, SWAP_CLUSTER_SPACE_COLS)
> >
> > -static int setup_swap_map_and_extents(struct swap_info_struct *p,
> > +static int setup_swap_map_and_extents(struct swap_info_struct *si,
> > union swap_header *swap_header,
> > unsigned char *swap_map,
> > struct swap_cluster_info *cluster_info,
> > @@ -3153,19 +3153,19 @@ static int setup_swap_map_and_extents(struct swap_info_struct *p,
> > unsigned int nr_good_pages;
> > int nr_extents;
> > unsigned long nr_clusters = DIV_ROUND_UP(maxpages, SWAPFILE_CLUSTER);
> > - unsigned long col = p->cluster_next / SWAPFILE_CLUSTER % SWAP_CLUSTER_COLS;
> > + unsigned long col = si->cluster_next / SWAPFILE_CLUSTER % SWAP_CLUSTER_COLS;
> > unsigned long i, idx;
> >
> > nr_good_pages = maxpages - 1; /* omit header page */
> >
> > - INIT_LIST_HEAD(&p->free_clusters);
> > - INIT_LIST_HEAD(&p->full_clusters);
> > - INIT_LIST_HEAD(&p->discard_clusters);
> > + INIT_LIST_HEAD(&si->free_clusters);
> > + INIT_LIST_HEAD(&si->full_clusters);
> > + INIT_LIST_HEAD(&si->discard_clusters);
> >
> > for (i = 0; i < SWAP_NR_ORDERS; i++) {
> > - INIT_LIST_HEAD(&p->nonfull_clusters[i]);
> > - INIT_LIST_HEAD(&p->frag_clusters[i]);
> > - p->frag_cluster_nr[i] = 0;
> > + INIT_LIST_HEAD(&si->nonfull_clusters[i]);
> > + INIT_LIST_HEAD(&si->frag_clusters[i]);
> > + si->frag_cluster_nr[i] = 0;
> > }
> >
> > for (i = 0; i < swap_header->info.nr_badpages; i++) {
> > @@ -3179,13 +3179,13 @@ static int setup_swap_map_and_extents(struct swap_info_struct *p,
> > * Haven't marked the cluster free yet, no list
> > * operation involved
> > */
> > - inc_cluster_info_page(p, cluster_info, page_nr);
> > + inc_cluster_info_page(si, cluster_info, page_nr);
> > }
> > }
> >
> > /* Haven't marked the cluster free yet, no list operation involved */
> > for (i = maxpages; i < round_up(maxpages, SWAPFILE_CLUSTER); i++)
> > - inc_cluster_info_page(p, cluster_info, i);
> > + inc_cluster_info_page(si, cluster_info, i);
> >
> > if (nr_good_pages) {
> > swap_map[0] = SWAP_MAP_BAD;
> > @@ -3193,13 +3193,13 @@ static int setup_swap_map_and_extents(struct swap_info_struct *p,
> > * Not mark the cluster free yet, no list
> > * operation involved
> > */
> > - inc_cluster_info_page(p, cluster_info, 0);
> > - p->max = maxpages;
> > - p->pages = nr_good_pages;
> > - nr_extents = setup_swap_extents(p, span);
> > + inc_cluster_info_page(si, cluster_info, 0);
> > + si->max = maxpages;
> > + si->pages = nr_good_pages;
> > + nr_extents = setup_swap_extents(si, span);
> > if (nr_extents < 0)
> > return nr_extents;
> > - nr_good_pages = p->pages;
> > + nr_good_pages = si->pages;
> > }
> > if (!nr_good_pages) {
> > pr_warn("Empty swap-file\n");
> > @@ -3223,11 +3223,11 @@ static int setup_swap_map_and_extents(struct swap_info_struct *p,
> > continue;
> > if (ci->count) {
> > ci->flags = CLUSTER_FLAG_NONFULL;
> > - list_add_tail(&ci->list, &p->nonfull_clusters[0]);
> > + list_add_tail(&ci->list, &si->nonfull_clusters[0]);
> > continue;
> > }
> > ci->flags = CLUSTER_FLAG_FREE;
> > - list_add_tail(&ci->list, &p->free_clusters);
> > + list_add_tail(&ci->list, &si->free_clusters);
> > }
> > }
> > return nr_extents;
> > @@ -3235,7 +3235,7 @@ static int setup_swap_map_and_extents(struct swap_info_struct *p,
> >
> > SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
> > {
> > - struct swap_info_struct *p;
> > + struct swap_info_struct *si;
> > struct filename *name;
> > struct file *swap_file = NULL;
> > struct address_space *mapping;
> > @@ -3261,11 +3261,11 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
> > if (!swap_avail_heads)
> > return -ENOMEM;
> >
> > - p = alloc_swap_info();
> > - if (IS_ERR(p))
> > - return PTR_ERR(p);
> > + si = alloc_swap_info();
> > + if (IS_ERR(si))
> > + return PTR_ERR(si);
> >
> > - INIT_WORK(&p->discard_work, swap_discard_work);
> > + INIT_WORK(&si->discard_work, swap_discard_work);
> >
> > name = getname(specialfile);
> > if (IS_ERR(name)) {
> > @@ -3280,12 +3280,12 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
> > goto bad_swap;
> > }
> >
> > - p->swap_file = swap_file;
> > + si->swap_file = swap_file;
> > mapping = swap_file->f_mapping;
> > dentry = swap_file->f_path.dentry;
> > inode = mapping->host;
> >
> > - error = claim_swapfile(p, inode);
> > + error = claim_swapfile(si, inode);
> > if (unlikely(error))
> > goto bad_swap;
> >
> > @@ -3313,7 +3313,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
> > }
> > swap_header = kmap(page);
> >
> > - maxpages = read_swap_header(p, swap_header, inode);
> > + maxpages = read_swap_header(si, swap_header, inode);
> > if (unlikely(!maxpages)) {
> > error = -EINVAL;
> > goto bad_swap_unlock_inode;
> > @@ -3326,19 +3326,19 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
> > goto bad_swap_unlock_inode;
> > }
> >
> > - if (p->bdev && bdev_stable_writes(p->bdev))
> > - p->flags |= SWP_STABLE_WRITES;
> > + if (si->bdev && bdev_stable_writes(si->bdev))
> > + si->flags |= SWP_STABLE_WRITES;
> >
> > - if (p->bdev && bdev_synchronous(p->bdev))
> > - p->flags |= SWP_SYNCHRONOUS_IO;
> > + if (si->bdev && bdev_synchronous(si->bdev))
> > + si->flags |= SWP_SYNCHRONOUS_IO;
> >
> > - if (p->bdev && bdev_nonrot(p->bdev)) {
> > + if (si->bdev && bdev_nonrot(si->bdev)) {
> > int cpu, i;
> > unsigned long ci, nr_cluster;
> >
> > - p->flags |= SWP_SOLIDSTATE;
> > - p->cluster_next_cpu = alloc_percpu(unsigned int);
> > - if (!p->cluster_next_cpu) {
> > + si->flags |= SWP_SOLIDSTATE;
> > + si->cluster_next_cpu = alloc_percpu(unsigned int);
> > + if (!si->cluster_next_cpu) {
> > error = -ENOMEM;
> > goto bad_swap_unlock_inode;
> > }
> > @@ -3347,8 +3347,8 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
> > * SSD
> > */
> > for_each_possible_cpu(cpu) {
> > - per_cpu(*p->cluster_next_cpu, cpu) =
> > - get_random_u32_inclusive(1, p->highest_bit);
> > + per_cpu(*si->cluster_next_cpu, cpu) =
> > + get_random_u32_inclusive(1, si->highest_bit);
> > }
> > nr_cluster = DIV_ROUND_UP(maxpages, SWAPFILE_CLUSTER);
> >
> > @@ -3362,15 +3362,15 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
> > for (ci = 0; ci < nr_cluster; ci++)
> > spin_lock_init(&((cluster_info + ci)->lock));
> >
> > - p->percpu_cluster = alloc_percpu(struct percpu_cluster);
> > - if (!p->percpu_cluster) {
> > + si->percpu_cluster = alloc_percpu(struct percpu_cluster);
> > + if (!si->percpu_cluster) {
> > error = -ENOMEM;
> > goto bad_swap_unlock_inode;
> > }
> > for_each_possible_cpu(cpu) {
> > struct percpu_cluster *cluster;
> >
> > - cluster = per_cpu_ptr(p->percpu_cluster, cpu);
> > + cluster = per_cpu_ptr(si->percpu_cluster, cpu);
> > for (i = 0; i < SWAP_NR_ORDERS; i++)
> > cluster->next[i] = SWAP_NEXT_INVALID;
> > }
> > @@ -3379,11 +3379,11 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
> > inced_nr_rotate_swap = true;
> > }
> >
> > - error = swap_cgroup_swapon(p->type, maxpages);
> > + error = swap_cgroup_swapon(si->type, maxpages);
> > if (error)
> > goto bad_swap_unlock_inode;
> >
> > - nr_extents = setup_swap_map_and_extents(p, swap_header, swap_map,
> > + nr_extents = setup_swap_map_and_extents(si, swap_header, swap_map,
> > cluster_info, maxpages, &span);
> > if (unlikely(nr_extents < 0)) {
> > error = nr_extents;
> > @@ -3391,14 +3391,14 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
> > }
> >
> > if ((swap_flags & SWAP_FLAG_DISCARD) &&
> > - p->bdev && bdev_max_discard_sectors(p->bdev)) {
> > + si->bdev && bdev_max_discard_sectors(si->bdev)) {
> > /*
> > * When discard is enabled for swap with no particular
> > * policy flagged, we set all swap discard flags here in
> > * order to sustain backward compatibility with older
> > * swapon(8) releases.
> > */
> > - p->flags |= (SWP_DISCARDABLE | SWP_AREA_DISCARD |
> > + si->flags |= (SWP_DISCARDABLE | SWP_AREA_DISCARD |
> > SWP_PAGE_DISCARD);
> >
> > /*
> > @@ -3408,24 +3408,24 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
> > * Now it's time to adjust the p->flags accordingly.
> > */
> > if (swap_flags & SWAP_FLAG_DISCARD_ONCE)
> > - p->flags &= ~SWP_PAGE_DISCARD;
> > + si->flags &= ~SWP_PAGE_DISCARD;
> > else if (swap_flags & SWAP_FLAG_DISCARD_PAGES)
> > - p->flags &= ~SWP_AREA_DISCARD;
> > + si->flags &= ~SWP_AREA_DISCARD;
> >
> > /* issue a swapon-time discard if it's still required */
> > - if (p->flags & SWP_AREA_DISCARD) {
> > - int err = discard_swap(p);
> > + if (si->flags & SWP_AREA_DISCARD) {
> > + int err = discard_swap(si);
> > if (unlikely(err))
> > pr_err("swapon: discard_swap(%p): %d\n",
> > - p, err);
> > + si, err);
> > }
> > }
> >
> > - error = init_swap_address_space(p->type, maxpages);
> > + error = init_swap_address_space(si->type, maxpages);
> > if (error)
> > goto bad_swap_unlock_inode;
> >
> > - error = zswap_swapon(p->type, maxpages);
> > + error = zswap_swapon(si->type, maxpages);
> > if (error)
> > goto free_swap_address_space;
> >
> > @@ -3445,15 +3445,15 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
> > if (swap_flags & SWAP_FLAG_PREFER)
> > prio =
> > (swap_flags & SWAP_FLAG_PRIO_MASK) >> SWAP_FLAG_PRIO_SHIFT;
> > - enable_swap_info(p, prio, swap_map, cluster_info);
> > + enable_swap_info(si, prio, swap_map, cluster_info);
> >
> > pr_info("Adding %uk swap on %s. Priority:%d extents:%d across:%lluk %s%s%s%s\n",
> > - K(p->pages), name->name, p->prio, nr_extents,
> > + K(si->pages), name->name, si->prio, nr_extents,
> > K((unsigned long long)span),
> > - (p->flags & SWP_SOLIDSTATE) ? "SS" : "",
> > - (p->flags & SWP_DISCARDABLE) ? "D" : "",
> > - (p->flags & SWP_AREA_DISCARD) ? "s" : "",
> > - (p->flags & SWP_PAGE_DISCARD) ? "c" : "");
> > + (si->flags & SWP_SOLIDSTATE) ? "SS" : "",
> > + (si->flags & SWP_DISCARDABLE) ? "D" : "",
> > + (si->flags & SWP_AREA_DISCARD) ? "s" : "",
> > + (si->flags & SWP_PAGE_DISCARD) ? "c" : "");
> >
> > mutex_unlock(&swapon_mutex);
> > atomic_inc(&proc_poll_event);
> > @@ -3462,22 +3462,22 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
> > error = 0;
> > goto out;
> > free_swap_zswap:
> > - zswap_swapoff(p->type);
> > + zswap_swapoff(si->type);
> > free_swap_address_space:
> > - exit_swap_address_space(p->type);
> > + exit_swap_address_space(si->type);
> > bad_swap_unlock_inode:
> > inode_unlock(inode);
> > bad_swap:
> > - free_percpu(p->percpu_cluster);
> > - p->percpu_cluster = NULL;
> > - free_percpu(p->cluster_next_cpu);
> > - p->cluster_next_cpu = NULL;
> > + free_percpu(si->percpu_cluster);
> > + si->percpu_cluster = NULL;
> > + free_percpu(si->cluster_next_cpu);
> > + si->cluster_next_cpu = NULL;
> > inode = NULL;
> > - destroy_swap_extents(p);
> > - swap_cgroup_swapoff(p->type);
> > + destroy_swap_extents(si);
> > + swap_cgroup_swapoff(si->type);
> > spin_lock(&swap_lock);
> > - p->swap_file = NULL;
> > - p->flags = 0;
> > + si->swap_file = NULL;
> > + si->flags = 0;
> > spin_unlock(&swap_lock);
> > vfree(swap_map);
> > kvfree(cluster_info);
> > @@ -3529,23 +3529,23 @@ void si_swapinfo(struct sysinfo *val)
> > */
> > static int __swap_duplicate(swp_entry_t entry, unsigned char usage, int nr)
> > {
> > - struct swap_info_struct *p;
> > + struct swap_info_struct *si;
> > struct swap_cluster_info *ci;
> > unsigned long offset;
> > unsigned char count;
> > unsigned char has_cache;
> > int err, i;
> >
> > - p = swp_swap_info(entry);
> > + si = swp_swap_info(entry);
> >
> > offset = swp_offset(entry);
> > VM_WARN_ON(nr > SWAPFILE_CLUSTER - offset % SWAPFILE_CLUSTER);
> > VM_WARN_ON(usage == 1 && nr > 1);
> > - ci = lock_cluster_or_swap_info(p, offset);
> > + ci = lock_cluster_or_swap_info(si, offset);
> >
> > err = 0;
> > for (i = 0; i < nr; i++) {
> > - count = p->swap_map[offset + i];
> > + count = si->swap_map[offset + i];
> >
> > /*
> > * swapin_readahead() doesn't check if a swap entry is valid, so the
> > @@ -3573,7 +3573,7 @@ static int __swap_duplicate(swp_entry_t entry, unsigned char usage, int nr)
> > }
> >
> > for (i = 0; i < nr; i++) {
> > - count = p->swap_map[offset + i];
> > + count = si->swap_map[offset + i];
> > has_cache = count & SWAP_HAS_CACHE;
> > count &= ~SWAP_HAS_CACHE;
> >
> > @@ -3581,7 +3581,7 @@ static int __swap_duplicate(swp_entry_t entry, unsigned char usage, int nr)
> > has_cache = SWAP_HAS_CACHE;
> > else if ((count & ~COUNT_CONTINUED) < SWAP_MAP_MAX)
> > count += usage;
> > - else if (swap_count_continued(p, offset + i, count))
> > + else if (swap_count_continued(si, offset + i, count))
> > count = COUNT_CONTINUED;
> > else {
> > /*
> > @@ -3592,11 +3592,11 @@ static int __swap_duplicate(swp_entry_t entry, unsigned char usage, int nr)
> > goto unlock_out;
> > }
> >
> > - WRITE_ONCE(p->swap_map[offset + i], count | has_cache);
> > + WRITE_ONCE(si->swap_map[offset + i], count | has_cache);
> > }
> >
> > unlock_out:
> > - unlock_cluster_or_swap_info(p, ci);
> > + unlock_cluster_or_swap_info(si, ci);
> > return err;
> > }
> >
> > --
> > 2.34.1
> >
Thanks
Barry
