freebsd-dev/sys/netinet/tcp_hpts.h
2020-09-01 21:19:14 +00:00

268 lines
9.9 KiB
C

/*-
* Copyright (c) 2016-2018 Netflix, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef __tcp_hpts_h__
#define __tcp_hpts_h__
/*
* The hpts uses a 102400 wheel. The wheel
* defines the time in 10 usec increments (102400 x 10).
* This gives a range of 10usec - 1024ms to place
* an entry within. If the user requests more than
* 1.024 second, a remaineder is attached and the hpts
* when seeing the remainder will re-insert the
* inpcb forward in time from where it is until
* the remainder is zero.
*/
#define NUM_OF_HPTSI_SLOTS 102400
TAILQ_HEAD(hptsh, inpcb);
/* Number of useconds in a hpts tick */
#define HPTS_TICKS_PER_USEC 10
#define HPTS_MS_TO_SLOTS(x) ((x * 100) + 1)
#define HPTS_USEC_TO_SLOTS(x) ((x+9) /10)
#define HPTS_USEC_IN_SEC 1000000
#define HPTS_MSEC_IN_SEC 1000
#define HPTS_USEC_IN_MSEC 1000
struct hpts_diag {
uint32_t p_hpts_active; /* bbr->flex7 x */
uint32_t p_nxt_slot; /* bbr->flex1 x */
uint32_t p_cur_slot; /* bbr->flex2 x */
uint32_t p_prev_slot; /* bbr->delivered */
uint32_t p_runningtick; /* bbr->inflight */
uint32_t slot_req; /* bbr->flex3 x */
uint32_t inp_hptsslot; /* bbr->flex4 x */
uint32_t slot_remaining; /* bbr->flex5 x */
uint32_t have_slept; /* bbr->epoch x */
uint32_t hpts_sleep_time; /* bbr->applimited x */
uint32_t yet_to_sleep; /* bbr->lt_epoch x */
uint32_t need_new_to; /* bbr->flex6 x */
uint32_t wheel_tick; /* bbr->bw_inuse x */
uint32_t maxticks; /* bbr->delRate x */
uint32_t wheel_cts; /* bbr->rttProp x */
int32_t co_ret; /* bbr->pkts_out x */
uint32_t p_curtick; /* upper bbr->cur_del_rate */
uint32_t p_lasttick; /* lower bbr->cur_del_rate */
uint8_t p_on_min_sleep; /* bbr->flex8 x */
};
/* Magic flags to tell whats cooking on the pacing wheel */
#define PACE_TMR_DELACK 0x01 /* Delayed ack timer running */
#define PACE_TMR_RACK 0x02 /* RACK timer running */
#define PACE_TMR_TLP 0x04 /* TLP timer running */
#define PACE_TMR_RXT 0x08 /* Retransmit timer running */
#define PACE_TMR_PERSIT 0x10 /* Persists timer running */
#define PACE_TMR_KEEP 0x20 /* Keep alive timer running */
#define PACE_PKT_OUTPUT 0x40 /* Output Packets being paced */
#define PACE_TMR_MASK (PACE_TMR_KEEP|PACE_TMR_PERSIT|PACE_TMR_RXT|PACE_TMR_TLP|PACE_TMR_RACK|PACE_TMR_DELACK)
#ifdef _KERNEL
/* Each hpts has its own p_mtx which is used for locking */
struct tcp_hpts_entry {
/* Cache line 0x00 */
struct mtx p_mtx; /* Mutex for hpts */
uint16_t p_hpts_active; /* Flag that says hpts is awake */
uint8_t p_hpts_wake_scheduled; /* Have we scheduled a wakeup? */
uint8_t p_wheel_complete; /* have we completed the wheel arc walk? */
uint32_t p_curtick; /* Tick in 10 us the hpts is going to */
uint32_t p_runningtick; /* Current tick we are at if we are running */
uint32_t p_prev_slot; /* Previous slot we were on */
uint32_t p_cur_slot; /* Current slot in wheel hpts is draining */
uint32_t p_nxt_slot; /* The next slot outside the current range of
* slots that the hpts is running on. */
int32_t p_on_queue_cnt; /* Count on queue in this hpts */
uint32_t p_lasttick; /* Last tick before the current one */
uint8_t p_direct_wake :1, /* boolean */
p_on_min_sleep:1, /* boolean */
p_avail:6;
uint8_t p_fill[3]; /* Fill to 32 bits */
/* Cache line 0x40 */
void *p_inp;
struct hptsh p_input; /* For the tcp-input runner */
/* Hptsi wheel */
struct hptsh *p_hptss;
int32_t p_on_inqueue_cnt; /* Count on input queue in this hpts */
uint32_t hit_no_enobuf;
uint32_t p_dyn_adjust;
uint32_t p_hpts_sleep_time; /* Current sleep interval having a max
* of 255ms */
uint32_t overidden_sleep; /* what was overrided by min-sleep for logging */
uint32_t saved_lasttick; /* for logging */
uint32_t saved_curtick; /* for logging */
uint32_t saved_curslot; /* for logging */
uint32_t saved_prev_slot; /* for logging */
uint32_t p_delayed_by; /* How much were we delayed by */
/* Cache line 0x80 */
struct sysctl_ctx_list hpts_ctx;
struct sysctl_oid *hpts_root;
struct intr_event *ie;
void *ie_cookie;
uint16_t p_num; /* The hpts number one per cpu */
uint16_t p_cpu; /* The hpts CPU */
/* There is extra space in here */
/* Cache line 0x100 */
struct callout co __aligned(CACHE_LINE_SIZE);
} __aligned(CACHE_LINE_SIZE);
struct tcp_hptsi {
struct proc *rp_proc; /* Process structure for hpts */
struct tcp_hpts_entry **rp_ent; /* Array of hptss */
uint32_t rp_num_hptss; /* Number of hpts threads */
};
#endif
#define HPTS_REMOVE_INPUT 0x01
#define HPTS_REMOVE_OUTPUT 0x02
#define HPTS_REMOVE_ALL (HPTS_REMOVE_INPUT | HPTS_REMOVE_OUTPUT)
/*
* When using the hpts, a TCP stack must make sure
* that once a INP_DROPPED flag is applied to a INP
* that it does not expect tcp_output() to ever be
* called by the hpts. The hpts will *not* call
* any output (or input) functions on a TCB that
* is in the DROPPED state.
*
* This implies final ACK's and RST's that might
* be sent when a TCB is still around must be
* sent from a routine like tcp_respond().
*/
#define DEFAULT_MIN_SLEEP 250 /* How many usec's is default for hpts sleep
* this determines min granularity of the
* hpts. If 0, granularity is 10useconds at
* the cost of more CPU (context switching). */
#ifdef _KERNEL
#define HPTS_MTX_ASSERT(hpts) mtx_assert(&(hpts)->p_mtx, MA_OWNED)
struct tcp_hpts_entry *tcp_hpts_lock(struct inpcb *inp);
struct tcp_hpts_entry *tcp_input_lock(struct inpcb *inp);
int __tcp_queue_to_hpts_immediate(struct inpcb *inp, int32_t line);
#define tcp_queue_to_hpts_immediate(a)__tcp_queue_to_hpts_immediate(a, __LINE__)
struct tcp_hpts_entry *tcp_cur_hpts(struct inpcb *inp);
#define tcp_hpts_remove(a, b) __tcp_hpts_remove(a, b, __LINE__)
void __tcp_hpts_remove(struct inpcb *inp, int32_t flags, int32_t line);
/*
* To insert a TCB on the hpts you *must* be holding the
* INP_WLOCK(). The hpts insert code will then acqurire
* the hpts's lock and insert the TCB on the requested
* slot possibly waking up the hpts if you are requesting
* a time earlier than what the hpts is sleeping to (if
* the hpts is sleeping). You may check the inp->inp_in_hpts
* flag without the hpts lock. The hpts is the only one
* that will clear this flag holding only the hpts lock. This
* means that in your tcp_output() routine when you test for
* it to be 1 (so you wont call output) it may be transitioning
* to 0 (by the hpts). That will be fine since that will just
* mean an extra call to tcp_output that most likely will find
* the call you executed (when the mis-match occured) will have
* put the TCB back on the hpts and it will return. If your
* call did not add it back to the hpts then you will either
* over-send or the cwnd will block you from sending more.
*
* Note you should also be holding the INP_WLOCK() when you
* call the remove from the hpts as well. Thoug usually
* you are either doing this from a timer, where you need
* that INP_WLOCK() or from destroying your TCB where again
* you should already have the INP_WLOCK().
*/
uint32_t __tcp_hpts_insert(struct inpcb *inp, uint32_t slot, int32_t line);
#define tcp_hpts_insert(a, b) __tcp_hpts_insert(a, b, __LINE__)
uint32_t
tcp_hpts_insert_diag(struct inpcb *inp, uint32_t slot, int32_t line, struct hpts_diag *diag);
int
__tcp_queue_to_input_locked(struct inpcb *inp, struct tcp_hpts_entry *hpts, int32_t line);
#define tcp_queue_to_input_locked(a, b) __tcp_queue_to_input_locked(a, b, __LINE__);
int
__tcp_queue_to_input(struct inpcb *inp, int32_t line);
#define tcp_queue_to_input(a) __tcp_queue_to_input(a, __LINE__)
uint16_t tcp_hpts_delayedby(struct inpcb *inp);
void __tcp_set_hpts(struct inpcb *inp, int32_t line);
#define tcp_set_hpts(a) __tcp_set_hpts(a, __LINE__)
void __tcp_set_inp_to_drop(struct inpcb *inp, uint16_t reason, int32_t line);
#define tcp_set_inp_to_drop(a, b) __tcp_set_inp_to_drop(a, b, __LINE__)
extern int32_t tcp_min_hptsi_time;
static __inline uint32_t
tcp_tv_to_hptstick(struct timeval *sv)
{
return ((sv->tv_sec * 100000) + (sv->tv_usec / 10));
}
static __inline uint32_t
tcp_gethptstick(struct timeval *sv)
{
struct timeval tv;
if (sv == NULL)
sv = &tv;
microuptime(sv);
return (tcp_tv_to_hptstick(sv));
}
static __inline uint32_t
tcp_tv_to_usectick(struct timeval *sv)
{
return ((uint32_t) ((sv->tv_sec * HPTS_USEC_IN_SEC) + sv->tv_usec));
}
static __inline uint32_t
tcp_tv_to_mssectick(struct timeval *sv)
{
return ((uint32_t) ((sv->tv_sec * HPTS_MSEC_IN_SEC) + (sv->tv_usec/HPTS_USEC_IN_MSEC)));
}
static __inline void
tcp_hpts_unlock(struct tcp_hpts_entry *hpts)
{
mtx_unlock(&hpts->p_mtx);
}
static __inline uint32_t
tcp_get_usecs(struct timeval *tv)
{
struct timeval tvd;
if (tv == NULL)
tv = &tvd;
microuptime(tv);
return (tcp_tv_to_usectick(tv));
}
#endif /* _KERNEL */
#endif /* __tcp_hpts_h__ */