/* * net/sched/sch_fifo.c The simplest FIFO queue. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * * Authors: Alexey Kuznetsov, */ #include #include #include #include #include #include #include /* 1 band FIFO pseudo-"scheduler" */ static int bfifo_enqueue(struct sk_buff *skb, struct Qdisc *sch, struct sk_buff **to_free) { if (likely(sch->qstats.backlog + qdisc_pkt_len(skb) <= sch->limit)) return qdisc_enqueue_tail(skb, sch); return qdisc_drop(skb, sch, to_free); } static int pfifo_enqueue(struct sk_buff *skb, struct Qdisc *sch, struct sk_buff **to_free) { if (likely(sch->q.qlen < sch->limit)) return qdisc_enqueue_tail(skb, sch); return qdisc_drop(skb, sch, to_free); } static int pfifo_tail_enqueue(struct sk_buff *skb, struct Qdisc *sch, struct sk_buff **to_free) { unsigned int prev_backlog; if (likely(sch->q.qlen < sch->limit)) return qdisc_enqueue_tail(skb, sch); prev_backlog = sch->qstats.backlog; /* queue full, remove one skb to fulfill the limit */ __qdisc_queue_drop_head(sch, &sch->q, to_free); qdisc_qstats_drop(sch); qdisc_enqueue_tail(skb, sch); qdisc_tree_reduce_backlog(sch, 0, prev_backlog - sch->qstats.backlog); return NET_XMIT_CN; } static int fifo_init(struct Qdisc *sch, struct nlattr *opt) { bool bypass; bool is_bfifo = sch->ops == &bfifo_qdisc_ops; if (opt == NULL) { u32 limit = qdisc_dev(sch)->tx_queue_len; if (is_bfifo) limit *= psched_mtu(qdisc_dev(sch)); sch->limit = limit; } else { struct tc_fifo_qopt *ctl = nla_data(opt); if (nla_len(opt) < sizeof(*ctl)) return -EINVAL; sch->limit = ctl->limit; } if (is_bfifo) bypass = sch->limit >= psched_mtu(qdisc_dev(sch)); else bypass = sch->limit >= 1; if (bypass) sch->flags |= TCQ_F_CAN_BYPASS; else sch->flags &= ~TCQ_F_CAN_BYPASS; return 0; } static int fifo_dump(struct Qdisc *sch, struct sk_buff *skb) { struct tc_fifo_qopt opt = { .limit = sch->limit }; if (nla_put(skb, TCA_OPTIONS, sizeof(opt), &opt)) goto nla_put_failure; return skb->len; nla_put_failure: return -1; } struct Qdisc_ops pfifo_qdisc_ops __read_mostly = { .id = "pfifo", .priv_size = 0, .enqueue = pfifo_enqueue, .dequeue = qdisc_dequeue_head, .peek = qdisc_peek_head, .init = fifo_init, .reset = qdisc_reset_queue, .change = fifo_init, .dump = fifo_dump, .owner = THIS_MODULE, }; EXPORT_SYMBOL(pfifo_qdisc_ops); struct Qdisc_ops bfifo_qdisc_ops __read_mostly = { .id = "bfifo", .priv_size = 0, .enqueue = bfifo_enqueue, .dequeue = qdisc_dequeue_head, .peek = qdisc_peek_head, .init = fifo_init, .reset = qdisc_reset_queue, .change = fifo_init, .dump = fifo_dump, .owner = THIS_MODULE, }; EXPORT_SYMBOL(bfifo_qdisc_ops); struct Qdisc_ops pfifo_head_drop_qdisc_ops __read_mostly = { .id = "pfifo_head_drop", .priv_size = 0, .enqueue = pfifo_tail_enqueue, .dequeue = qdisc_dequeue_head, .peek = qdisc_peek_head, .init = fifo_init, .reset = qdisc_reset_queue, .change = fifo_init, .dump = fifo_dump, .owner = THIS_MODULE, }; /* Pass size change message down to embedded FIFO */ int fifo_set_limit(struct Qdisc *q, unsigned int limit) { struct nlattr *nla; int ret = -ENOMEM; /* Hack to avoid sending change message to non-FIFO */ if (strncmp(q->ops->id + 1, "fifo", 4) != 0) return 0; nla = kmalloc(nla_attr_size(sizeof(struct tc_fifo_qopt)), GFP_KERNEL); if (nla) { nla->nla_type = RTM_NEWQDISC; nla->nla_len = nla_attr_size(sizeof(struct tc_fifo_qopt)); ((struct tc_fifo_qopt *)nla_data(nla))->limit = limit; ret = q->ops->change(q, nla); kfree(nla); } return ret; } EXPORT_SYMBOL(fifo_set_limit); struct Qdisc *fifo_create_dflt(struct Qdisc *sch, struct Qdisc_ops *ops, unsigned int limit) { struct Qdisc *q; int err = -ENOMEM; q = qdisc_create_dflt(sch->dev_queue, ops, TC_H_MAKE(sch->handle, 1)); if (q) { err = fifo_set_limit(q, limit); if (err < 0) { qdisc_destroy(q); q = NULL; } } return q ? : ERR_PTR(err); } EXPORT_SYMBOL(fifo_create_dflt); onchange='this.form.submit();'>mode:
authorJungseung Lee <js07.lee@samsung.com>2016-12-12 16:46:43 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2016-12-12 18:55:10 -0800
commit39a0e975c37dee93fa1b8ea5f7eacd1c4c8a586e (patch)
tree34df14285ce89f83a93f6053a897bcd371dc1e15 /tools/objtool/Documentation/stack-validation.txt
parent30f74aa0854c2d5a331b507b14fe421ba4980511 (diff)
init: reduce rootwait polling interval time to 5ms
For several devices, the rootwait time is sensitive because it directly affects booting time. The polling interval of rootwait is currently 100ms. To save unnessesary waiting time, reduce the polling interval to 5 ms. [akpm@linux-foundation.org: remove used-once #define] Link: http://lkml.kernel.org/r/20161207060743.1728-1-js07.lee@samsung.com Signed-off-by: Jungseung Lee <js07.lee@samsung.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'tools/objtool/Documentation/stack-validation.txt')