LU-12748 readahead: limit async ra requests

[fs/lustre-release.git] / lustre / llite / rw.c

diff --git a/lustre/llite/rw.c b/lustre/llite/rw.c
index 89ea7fb..6161bdc 100644 (file)
--- a/lustre/llite/rw.c
+++ b/lustre/llite/rw.c
@@ -528,6 +528,7 @@ static void ll_readahead_handle_work(struct work_struct *wq)
        __u64 kms;
        int rc;
        pgoff_t eof_index;
+       struct ll_sb_info *sbi;
 
        work = container_of(wq, struct ll_readahead_work,
                            lrw_readahead_work);
@@ -535,6 +536,7 @@ static void ll_readahead_handle_work(struct work_struct *wq)
        ras = &fd->fd_ras;
        file = work->lrw_file;
        inode = file_inode(file);
+       sbi = ll_i2sbi(inode);
 
        env = cl_env_alloc(&refcheck, LCT_NOREF);
        if (IS_ERR(env))
@@ -567,7 +569,7 @@ static void ll_readahead_handle_work(struct work_struct *wq)
 
        ria->ria_end_idx = work->lrw_end_idx;
        pages = ria->ria_end_idx - ria->ria_start_idx + 1;
-       ria->ria_reserved = ll_ra_count_get(ll_i2sbi(inode), ria,
+       ria->ria_reserved = ll_ra_count_get(sbi, ria,
                                            ria_page_count(ria), pages_min);
 
        CDEBUG(D_READA,
@@ -631,6 +633,7 @@ out_put_env:
 out_free_work:
        if (ra_end_idx > 0)
                ll_ra_stats_inc_sbi(ll_i2sbi(inode), RA_STAT_ASYNC);
+       atomic_dec(&sbi->ll_ra_info.ra_async_inflight);
        ll_readahead_work_free(work);
 }
 
@@ -1479,7 +1482,8 @@ static int kickoff_async_readahead(struct file *file, unsigned long pages)
         * we do async readahead, allowing the user thread to do fast i/o.
         */
        if (stride_io_mode(ras) || !throttle ||
-           ras->ras_window_pages < throttle)
+           ras->ras_window_pages < throttle ||
+           atomic_read(&ra->ra_async_inflight) > ra->ra_async_max_active)
                return 0;
 
        if ((atomic_read(&ra->ra_cur_pages) + pages) > ra->ra_max_pages)
@@ -1491,6 +1495,7 @@ static int kickoff_async_readahead(struct file *file, unsigned long pages)
        /* ll_readahead_work_free() free it */
        OBD_ALLOC_PTR(lrw);
        if (lrw) {
+               atomic_inc(&sbi->ll_ra_info.ra_async_inflight);
                lrw->lrw_file = get_file(file);
                lrw->lrw_start_idx = start_idx;
                lrw->lrw_end_idx = end_idx;