From 1122f40072731525c06b1371cfa30112b9b54d27 Mon Sep 17 00:00:00 2001 From: Xin Yin Date: Thu, 25 Aug 2022 10:09:45 +0800 Subject: cachefiles: make on-demand request distribution fairer For now, enqueuing and dequeuing on-demand requests all start from idx 0, this makes request distribution unfair. In the weighty concurrent I/O scenario, the request stored in higher idx will starve. Searching requests cyclically in cachefiles_ondemand_daemon_read, makes distribution fairer. Fixes: c8383054506c ("cachefiles: notify the user daemon when looking up cookie") Reported-by: Yongqing Li Signed-off-by: Xin Yin Signed-off-by: David Howells Reviewed-by: Jeffle Xu Reviewed-by: Gao Xiang Link: https://lore.kernel.org/r/20220817065200.11543-1-yinxin.x@bytedance.com/ # v1 Link: https://lore.kernel.org/r/20220825020945.2293-1-yinxin.x@bytedance.com/ # v2 --- fs/cachefiles/internal.h | 1 + 1 file changed, 1 insertion(+) (limited to 'fs/cachefiles/internal.h') diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h index 6cba2c6de2f9..2ad58c465208 100644 --- a/fs/cachefiles/internal.h +++ b/fs/cachefiles/internal.h @@ -111,6 +111,7 @@ struct cachefiles_cache { char *tag; /* cache binding tag */ refcount_t unbind_pincount;/* refcount to do daemon unbind */ struct xarray reqs; /* xarray of pending on-demand requests */ + unsigned long req_id_next; struct xarray ondemand_ids; /* xarray for ondemand_id allocation */ u32 ondemand_id_next; }; -- cgit