diff options
| author | Tejun Heo <tj@kernel.org> | 2015-05-22 17:13:35 -0400 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2015-06-02 08:33:35 -0600 |
| commit | 4aa9c692e052cf6db99db62a8fe0543e5c455da7 (patch) | |
| tree | 378d5b44e7ec769dd4dfc9ac5ab2447fdb1f50a4 /mm/backing-dev.c | |
| parent | 8395cd9f813d5d7ed9870e642230acfcfc1e8a0a (diff) | |
| download | linux-4aa9c692e052cf6db99db62a8fe0543e5c455da7.tar.gz | |
bdi: separate out congested state into a separate struct
Currently, a wb's (bdi_writeback) congestion state is carried in its ->state field; however, cgroup writeback support will require multiple wb's sharing the same congestion state. This patch separates out congestion state into its own struct - struct bdi_writeback_congested. A new field wb field, wb_congested, points to its associated congested struct. The default wb, bdi->wb, always points to bdi->wb_congested. While this patch adds a layer of indirection, it doesn't introduce any behavior changes. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'mm/backing-dev.c')
| -rw-r--r-- | mm/backing-dev.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/mm/backing-dev.c b/mm/backing-dev.c index 805b2870ca4e..5ec7658cb984 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -383,6 +383,9 @@ int bdi_init(struct backing_dev_info *bdi) if (err) return err; + bdi->wb_congested.state = 0; + bdi->wb.congested = &bdi->wb_congested; + return 0; } EXPORT_SYMBOL(bdi_init); @@ -504,7 +507,7 @@ void clear_bdi_congested(struct backing_dev_info *bdi, int sync) wait_queue_head_t *wqh = &congestion_wqh[sync]; bit = sync ? WB_sync_congested : WB_async_congested; - if (test_and_clear_bit(bit, &bdi->wb.state)) + if (test_and_clear_bit(bit, &bdi->wb.congested->state)) atomic_dec(&nr_bdi_congested[sync]); smp_mb__after_atomic(); if (waitqueue_active(wqh)) @@ -517,7 +520,7 @@ void set_bdi_congested(struct backing_dev_info *bdi, int sync) enum wb_state bit; bit = sync ? WB_sync_congested : WB_async_congested; - if (!test_and_set_bit(bit, &bdi->wb.state)) + if (!test_and_set_bit(bit, &bdi->wb.congested->state)) atomic_inc(&nr_bdi_congested[sync]); } EXPORT_SYMBOL(set_bdi_congested); |