diff options
| author | Minchan Kim <minchan@kernel.org> | 2022-01-21 22:14:01 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-01-22 08:33:37 +0200 |
| commit | 3ae92ac23bd88ed18c43a5b138d5a91252c31d2a (patch) | |
| tree | 7db70266dd3802af8f27e4060348c7532e46ec9d /mm/zsmalloc.c | |
| parent | 0a5f079b810765be3bd931fce0f88154035af897 (diff) | |
zsmalloc: introduce obj_allocated
The usage pattern for obj_to_head is to check whether the zpage is
allocated or not. Thus, introduce obj_allocated.
Link: https://lkml.kernel.org/r/20211115185909.3949505-5-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/zsmalloc.c')
| -rw-r--r-- | mm/zsmalloc.c | 33 |
1 files changed, 16 insertions, 17 deletions
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index c45807f170e8..5c72fd5f8fac 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -877,13 +877,21 @@ static unsigned long handle_to_obj(unsigned long handle) return *(unsigned long *)handle; } -static unsigned long obj_to_head(struct page *page, void *obj) +static bool obj_allocated(struct page *page, void *obj, unsigned long *phandle) { + unsigned long handle; + if (unlikely(PageHugeObject(page))) { VM_BUG_ON_PAGE(!is_first_page(page), page); - return page->index; + handle = page->index; } else - return *(unsigned long *)obj; + handle = *(unsigned long *)obj; + + if (!(handle & OBJ_ALLOCATED_TAG)) + return false; + + *phandle = handle & ~OBJ_ALLOCATED_TAG; + return true; } static inline int testpin_tag(unsigned long handle) @@ -1606,7 +1614,6 @@ static void zs_object_copy(struct size_class *class, unsigned long dst, static unsigned long find_alloced_obj(struct size_class *class, struct page *page, int *obj_idx) { - unsigned long head; int offset = 0; int index = *obj_idx; unsigned long handle = 0; @@ -1616,9 +1623,7 @@ static unsigned long find_alloced_obj(struct size_class *class, offset += class->size * index; while (offset < PAGE_SIZE) { - head = obj_to_head(page, addr + offset); - if (head & OBJ_ALLOCATED_TAG) { - handle = head & ~OBJ_ALLOCATED_TAG; + if (obj_allocated(page, addr + offset, &handle)) { if (trypin_tag(handle)) break; handle = 0; @@ -1928,7 +1933,7 @@ static int zs_page_migrate(struct address_space *mapping, struct page *newpage, struct page *dummy; void *s_addr, *d_addr, *addr; int offset, pos; - unsigned long handle, head; + unsigned long handle; unsigned long old_obj, new_obj; unsigned int obj_idx; int ret = -EAGAIN; @@ -1964,9 +1969,7 @@ static int zs_page_migrate(struct address_space *mapping, struct page *newpage, pos = offset; s_addr = kmap_atomic(page); while (pos < PAGE_SIZE) { - head = obj_to_head(page, s_addr + pos); - if (head & OBJ_ALLOCATED_TAG) { - handle = head & ~OBJ_ALLOCATED_TAG; + if (obj_allocated(page, s_addr + pos, &handle)) { if (!trypin_tag(handle)) goto unpin_objects; } @@ -1982,9 +1985,7 @@ static int zs_page_migrate(struct address_space *mapping, struct page *newpage, for (addr = s_addr + offset; addr < s_addr + pos; addr += class->size) { - head = obj_to_head(page, addr); - if (head & OBJ_ALLOCATED_TAG) { - handle = head & ~OBJ_ALLOCATED_TAG; + if (obj_allocated(page, addr, &handle)) { BUG_ON(!testpin_tag(handle)); old_obj = handle_to_obj(handle); @@ -2029,9 +2030,7 @@ static int zs_page_migrate(struct address_space *mapping, struct page *newpage, unpin_objects: for (addr = s_addr + offset; addr < s_addr + pos; addr += class->size) { - head = obj_to_head(page, addr); - if (head & OBJ_ALLOCATED_TAG) { - handle = head & ~OBJ_ALLOCATED_TAG; + if (obj_allocated(page, addr, &handle)) { BUG_ON(!testpin_tag(handle)); unpin_tag(handle); } |