diff options
| author | Matthew Wilcox (Oracle) <willy@infradead.org> | 2024-02-15 07:36:45 +0100 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-02-23 17:48:37 -0800 |
| commit | 535c5d9dadb327bb35f6d780fa037e0d3dfcb568 (patch) | |
| tree | 6d66ab2d14acb02dc2469d5807e05e786a80ee9f /include/linux/pagevec.h | |
| parent | 807d1fe36077decf6f4ef8d4b63a084760a5c5fc (diff) | |
pagevec: add ability to iterate a queue
Add a loop counter inside the folio_batch to let us iterate from 0-nr
instead of decrementing nr and treating the batch as a stack. It would
generate some very weird and suboptimal I/O patterns for page writeback to
iterate over the batch as a stack.
Link: https://lkml.kernel.org/r/20240215063649.2164017-11-hch@lst.de
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Chinner <dchinner@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'include/linux/pagevec.h')
| -rw-r--r-- | include/linux/pagevec.h | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/include/linux/pagevec.h b/include/linux/pagevec.h index 87cc678adc85..fcc06c300a72 100644 --- a/include/linux/pagevec.h +++ b/include/linux/pagevec.h @@ -27,6 +27,7 @@ struct folio; */ struct folio_batch { unsigned char nr; + unsigned char i; bool percpu_pvec_drained; struct folio *folios[PAGEVEC_SIZE]; }; @@ -40,12 +41,14 @@ struct folio_batch { static inline void folio_batch_init(struct folio_batch *fbatch) { fbatch->nr = 0; + fbatch->i = 0; fbatch->percpu_pvec_drained = false; } static inline void folio_batch_reinit(struct folio_batch *fbatch) { fbatch->nr = 0; + fbatch->i = 0; } static inline unsigned int folio_batch_count(struct folio_batch *fbatch) @@ -75,6 +78,21 @@ static inline unsigned folio_batch_add(struct folio_batch *fbatch, return folio_batch_space(fbatch); } +/** + * folio_batch_next - Return the next folio to process. + * @fbatch: The folio batch being processed. + * + * Use this function to implement a queue of folios. + * + * Return: The next folio in the queue, or NULL if the queue is empty. + */ +static inline struct folio *folio_batch_next(struct folio_batch *fbatch) +{ + if (fbatch->i == fbatch->nr) + return NULL; + return fbatch->folios[fbatch->i++]; +} + void __folio_batch_release(struct folio_batch *pvec); static inline void folio_batch_release(struct folio_batch *fbatch) |