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authorDennis Zhou (Facebook) <dennisszhou@gmail.com>2017-07-24 19:02:10 -0400
committerTejun Heo <tj@kernel.org>2017-07-26 10:23:53 -0400
commit91e914c5a4988d00a13c14297ab02b250611e00e (patch)
treedb6c6ea3641569450508cb7a094b31764a79ec6b
parentd2f3c3849461baefdbb39123abde1054d46bf22e (diff)
percpu: generalize bitmap (un)populated iterators
The area map allocator only used a bitmap for the backing page state. The new bitmap allocator will use bitmaps to manage the allocation region in addition to this. This patch generalizes the bitmap iterators so they can be reused with the bitmap allocator. Signed-off-by: Dennis Zhou <dennisszhou@gmail.com> Reviewed-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org>
-rw-r--r--mm/percpu.c49
1 files changed, 25 insertions, 24 deletions
diff --git a/mm/percpu.c b/mm/percpu.c
index dc755721c333..84cc2559d4aa 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -253,35 +253,32 @@ static unsigned long pcpu_chunk_addr(struct pcpu_chunk *chunk,
pcpu_unit_page_offset(cpu, page_idx);
}
-static void __maybe_unused pcpu_next_unpop(struct pcpu_chunk *chunk,
- int *rs, int *re, int end)
+static void pcpu_next_unpop(unsigned long *bitmap, int *rs, int *re, int end)
{
- *rs = find_next_zero_bit(chunk->populated, end, *rs);
- *re = find_next_bit(chunk->populated, end, *rs + 1);
+ *rs = find_next_zero_bit(bitmap, end, *rs);
+ *re = find_next_bit(bitmap, end, *rs + 1);
}
-static void __maybe_unused pcpu_next_pop(struct pcpu_chunk *chunk,
- int *rs, int *re, int end)
+static void pcpu_next_pop(unsigned long *bitmap, int *rs, int *re, int end)
{
- *rs = find_next_bit(chunk->populated, end, *rs);
- *re = find_next_zero_bit(chunk->populated, end, *rs + 1);
+ *rs = find_next_bit(bitmap, end, *rs);
+ *re = find_next_zero_bit(bitmap, end, *rs + 1);
}
/*
- * (Un)populated page region iterators. Iterate over (un)populated
- * page regions between @start and @end in @chunk. @rs and @re should
- * be integer variables and will be set to start and end page index of
- * the current region.
+ * Bitmap region iterators. Iterates over the bitmap between
+ * [@start, @end) in @chunk. @rs and @re should be integer variables
+ * and will be set to start and end index of the current free region.
*/
-#define pcpu_for_each_unpop_region(chunk, rs, re, start, end) \
- for ((rs) = (start), pcpu_next_unpop((chunk), &(rs), &(re), (end)); \
- (rs) < (re); \
- (rs) = (re) + 1, pcpu_next_unpop((chunk), &(rs), &(re), (end)))
+#define pcpu_for_each_unpop_region(bitmap, rs, re, start, end) \
+ for ((rs) = (start), pcpu_next_unpop((bitmap), &(rs), &(re), (end)); \
+ (rs) < (re); \
+ (rs) = (re) + 1, pcpu_next_unpop((bitmap), &(rs), &(re), (end)))
-#define pcpu_for_each_pop_region(chunk, rs, re, start, end) \
- for ((rs) = (start), pcpu_next_pop((chunk), &(rs), &(re), (end)); \
- (rs) < (re); \
- (rs) = (re) + 1, pcpu_next_pop((chunk), &(rs), &(re), (end)))
+#define pcpu_for_each_pop_region(bitmap, rs, re, start, end) \
+ for ((rs) = (start), pcpu_next_pop((bitmap), &(rs), &(re), (end)); \
+ (rs) < (re); \
+ (rs) = (re) + 1, pcpu_next_pop((bitmap), &(rs), &(re), (end)))
/**
* pcpu_mem_zalloc - allocate memory
@@ -521,7 +518,8 @@ static int pcpu_fit_in_area(struct pcpu_chunk *chunk, int off, int this_size,
page_end = PFN_UP(head + off + size);
rs = page_start;
- pcpu_next_unpop(chunk, &rs, &re, PFN_UP(off + this_size));
+ pcpu_next_unpop(chunk->populated, &rs, &re,
+ PFN_UP(off + this_size));
if (rs >= page_end)
return head;
cand_off = re * PAGE_SIZE;
@@ -1071,7 +1069,8 @@ area_found:
page_start = PFN_DOWN(off);
page_end = PFN_UP(off + size);
- pcpu_for_each_unpop_region(chunk, rs, re, page_start, page_end) {
+ pcpu_for_each_unpop_region(chunk->populated, rs, re,
+ page_start, page_end) {
WARN_ON(chunk->immutable);
ret = pcpu_populate_chunk(chunk, rs, re);
@@ -1221,7 +1220,8 @@ static void pcpu_balance_workfn(struct work_struct *work)
list_for_each_entry_safe(chunk, next, &to_free, list) {
int rs, re;
- pcpu_for_each_pop_region(chunk, rs, re, 0, chunk->nr_pages) {
+ pcpu_for_each_pop_region(chunk->populated, rs, re, 0,
+ chunk->nr_pages) {
pcpu_depopulate_chunk(chunk, rs, re);
spin_lock_irq(&pcpu_lock);
pcpu_chunk_depopulated(chunk, rs, re);
@@ -1288,7 +1288,8 @@ retry_pop:
continue;
/* @chunk can't go away while pcpu_alloc_mutex is held */
- pcpu_for_each_unpop_region(chunk, rs, re, 0, chunk->nr_pages) {
+ pcpu_for_each_unpop_region(chunk->populated, rs, re, 0,
+ chunk->nr_pages) {
int nr = min(re - rs, nr_to_pop);
ret = pcpu_populate_chunk(chunk, rs, rs + nr);