mm: simplify try_to_unuse
Remove the unused frontswap and pages_to_unuse arguments, and mark the
function static now that the caller in frontswap is gone.
[[email protected]: fix shmem_unuse() stub, per Matthew]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Juergen Gross <[email protected]>
Cc: Dan Streetman <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Konrad Rzeszutek Wilk <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Cc: Seth Jennings <[email protected]>
Cc: Vitaly Wool <[email protected]>
Cc: Naresh Kamboju <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
diff --git a/mm/swapfile.c b/mm/swapfile.c
index df5930c..82342c7 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1923,8 +1923,7 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd,
static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
unsigned long addr, unsigned long end,
- unsigned int type, bool frontswap,
- unsigned long *fs_pages_to_unuse)
+ unsigned int type)
{
struct page *page;
swp_entry_t entry;
@@ -1945,9 +1944,6 @@ static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
continue;
offset = swp_offset(entry);
- if (frontswap && !frontswap_test(si, offset))
- continue;
-
pte_unmap(pte);
swap_map = &si->swap_map[offset];
page = lookup_swap_cache(entry, vma, addr);
@@ -1979,11 +1975,6 @@ static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
try_to_free_swap(page);
unlock_page(page);
put_page(page);
-
- if (*fs_pages_to_unuse && !--(*fs_pages_to_unuse)) {
- ret = FRONTSWAP_PAGES_UNUSED;
- goto out;
- }
try_next:
pte = pte_offset_map(pmd, addr);
} while (pte++, addr += PAGE_SIZE, addr != end);
@@ -1996,8 +1987,7 @@ static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
static inline int unuse_pmd_range(struct vm_area_struct *vma, pud_t *pud,
unsigned long addr, unsigned long end,
- unsigned int type, bool frontswap,
- unsigned long *fs_pages_to_unuse)
+ unsigned int type)
{
pmd_t *pmd;
unsigned long next;
@@ -2009,8 +1999,7 @@ static inline int unuse_pmd_range(struct vm_area_struct *vma, pud_t *pud,
next = pmd_addr_end(addr, end);
if (pmd_none_or_trans_huge_or_clear_bad(pmd))
continue;
- ret = unuse_pte_range(vma, pmd, addr, next, type,
- frontswap, fs_pages_to_unuse);
+ ret = unuse_pte_range(vma, pmd, addr, next, type);
if (ret)
return ret;
} while (pmd++, addr = next, addr != end);
@@ -2019,8 +2008,7 @@ static inline int unuse_pmd_range(struct vm_area_struct *vma, pud_t *pud,
static inline int unuse_pud_range(struct vm_area_struct *vma, p4d_t *p4d,
unsigned long addr, unsigned long end,
- unsigned int type, bool frontswap,
- unsigned long *fs_pages_to_unuse)
+ unsigned int type)
{
pud_t *pud;
unsigned long next;
@@ -2031,8 +2019,7 @@ static inline int unuse_pud_range(struct vm_area_struct *vma, p4d_t *p4d,
next = pud_addr_end(addr, end);
if (pud_none_or_clear_bad(pud))
continue;
- ret = unuse_pmd_range(vma, pud, addr, next, type,
- frontswap, fs_pages_to_unuse);
+ ret = unuse_pmd_range(vma, pud, addr, next, type);
if (ret)
return ret;
} while (pud++, addr = next, addr != end);
@@ -2041,8 +2028,7 @@ static inline int unuse_pud_range(struct vm_area_struct *vma, p4d_t *p4d,
static inline int unuse_p4d_range(struct vm_area_struct *vma, pgd_t *pgd,
unsigned long addr, unsigned long end,
- unsigned int type, bool frontswap,
- unsigned long *fs_pages_to_unuse)
+ unsigned int type)
{
p4d_t *p4d;
unsigned long next;
@@ -2053,16 +2039,14 @@ static inline int unuse_p4d_range(struct vm_area_struct *vma, pgd_t *pgd,
next = p4d_addr_end(addr, end);
if (p4d_none_or_clear_bad(p4d))
continue;
- ret = unuse_pud_range(vma, p4d, addr, next, type,
- frontswap, fs_pages_to_unuse);
+ ret = unuse_pud_range(vma, p4d, addr, next, type);
if (ret)
return ret;
} while (p4d++, addr = next, addr != end);
return 0;
}
-static int unuse_vma(struct vm_area_struct *vma, unsigned int type,
- bool frontswap, unsigned long *fs_pages_to_unuse)
+static int unuse_vma(struct vm_area_struct *vma, unsigned int type)
{
pgd_t *pgd;
unsigned long addr, end, next;
@@ -2076,16 +2060,14 @@ static int unuse_vma(struct vm_area_struct *vma, unsigned int type,
next = pgd_addr_end(addr, end);
if (pgd_none_or_clear_bad(pgd))
continue;
- ret = unuse_p4d_range(vma, pgd, addr, next, type,
- frontswap, fs_pages_to_unuse);
+ ret = unuse_p4d_range(vma, pgd, addr, next, type);
if (ret)
return ret;
} while (pgd++, addr = next, addr != end);
return 0;
}
-static int unuse_mm(struct mm_struct *mm, unsigned int type,
- bool frontswap, unsigned long *fs_pages_to_unuse)
+static int unuse_mm(struct mm_struct *mm, unsigned int type)
{
struct vm_area_struct *vma;
int ret = 0;
@@ -2093,8 +2075,7 @@ static int unuse_mm(struct mm_struct *mm, unsigned int type,
mmap_read_lock(mm);
for (vma = mm->mmap; vma; vma = vma->vm_next) {
if (vma->anon_vma) {
- ret = unuse_vma(vma, type, frontswap,
- fs_pages_to_unuse);
+ ret = unuse_vma(vma, type);
if (ret)
break;
}
@@ -2110,7 +2091,7 @@ static int unuse_mm(struct mm_struct *mm, unsigned int type,
* if there are no inuse entries after prev till end of the map.
*/
static unsigned int find_next_to_unuse(struct swap_info_struct *si,
- unsigned int prev, bool frontswap)
+ unsigned int prev)
{
unsigned int i;
unsigned char count;
@@ -2124,8 +2105,7 @@ static unsigned int find_next_to_unuse(struct swap_info_struct *si,
for (i = prev + 1; i < si->max; i++) {
count = READ_ONCE(si->swap_map[i]);
if (count && swap_count(count) != SWAP_MAP_BAD)
- if (!frontswap || frontswap_test(si, i))
- break;
+ break;
if ((i % LATENCY_LIMIT) == 0)
cond_resched();
}
@@ -2136,12 +2116,7 @@ static unsigned int find_next_to_unuse(struct swap_info_struct *si,
return i;
}
-/*
- * If the boolean frontswap is true, only unuse pages_to_unuse pages;
- * pages_to_unuse==0 means all pages; ignored if frontswap is false
- */
-int try_to_unuse(unsigned int type, bool frontswap,
- unsigned long pages_to_unuse)
+static int try_to_unuse(unsigned int type)
{
struct mm_struct *prev_mm;
struct mm_struct *mm;
@@ -2155,13 +2130,10 @@ int try_to_unuse(unsigned int type, bool frontswap,
if (!READ_ONCE(si->inuse_pages))
return 0;
- if (!frontswap)
- pages_to_unuse = 0;
-
retry:
- retval = shmem_unuse(type, frontswap, &pages_to_unuse);
+ retval = shmem_unuse(type);
if (retval)
- goto out;
+ return retval;
prev_mm = &init_mm;
mmget(prev_mm);
@@ -2178,11 +2150,10 @@ int try_to_unuse(unsigned int type, bool frontswap,
spin_unlock(&mmlist_lock);
mmput(prev_mm);
prev_mm = mm;
- retval = unuse_mm(mm, type, frontswap, &pages_to_unuse);
-
+ retval = unuse_mm(mm, type);
if (retval) {
mmput(prev_mm);
- goto out;
+ return retval;
}
/*
@@ -2199,7 +2170,7 @@ int try_to_unuse(unsigned int type, bool frontswap,
i = 0;
while (READ_ONCE(si->inuse_pages) &&
!signal_pending(current) &&
- (i = find_next_to_unuse(si, i, frontswap)) != 0) {
+ (i = find_next_to_unuse(si, i)) != 0) {
entry = swp_entry(type, i);
page = find_get_page(swap_address_space(entry), i);
@@ -2217,14 +2188,6 @@ int try_to_unuse(unsigned int type, bool frontswap,
try_to_free_swap(page);
unlock_page(page);
put_page(page);
-
- /*
- * For frontswap, we just need to unuse pages_to_unuse, if
- * it was specified. Need not check frontswap again here as
- * we already zeroed out pages_to_unuse if not frontswap.
- */
- if (pages_to_unuse && --pages_to_unuse == 0)
- goto out;
}
/*
@@ -2242,10 +2205,10 @@ int try_to_unuse(unsigned int type, bool frontswap,
if (READ_ONCE(si->inuse_pages)) {
if (!signal_pending(current))
goto retry;
- retval = -EINTR;
+ return -EINTR;
}
-out:
- return (retval == FRONTSWAP_PAGES_UNUSED) ? 0 : retval;
+
+ return 0;
}
/*
@@ -2577,7 +2540,7 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile)
disable_swap_slots_cache_lock();
set_current_oom_origin();
- err = try_to_unuse(p->type, false, 0); /* force unuse all pages */
+ err = try_to_unuse(p->type);
clear_current_oom_origin();
if (err) {
