xref: /illumos-gate/usr/src/man/man9e/mri_stat.9e (revision dd72704bd9e794056c558153663c739e2012d721)
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12.\" Copyright (c) 2017, Joyent, Inc.
13.\" Copyright 2022 Oxide Computer Company
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15.Dd July 2, 2022
16.Dt MRI_STAT 9E
17.Os
18.Sh NAME
19.Nm mri_stat
20.Nd xtatistics collection entry point for rings
21.Sh SYNOPSIS
22.In sys/mac_provider.h
23.Ft int
24.Fo prefix_ring_stat
25.Fa "mac_ring_driver_t rh"
26.Fa "uint_t stat"
27.Fa "uint64_t *val"
28.Fc
29.Sh INTERFACE LEVEL
30.Sy Uncommitted -
31This interface is still evolving.
32API and ABI stability is not guaranteed.
33.Sh PARAMETERS
34.Bl -tag -width Fa
35.It Fa rh
36A pointer to the ring's private data that was passed in via the
37.Vt mri_driver
38member of the
39.Xr mac_ring_info 9S
40structure as part of the
41.Xr mr_rget 9E
42entry point.
43.It Fa stat
44The numeric identifier of a statistic.
45.It Fa val
46A pointer to a 64-bit unsigned value into which the device driver should
47place statistic.
48.El
49.Sh DESCRIPTION
50The
51.Fn mri_stat
52entry point is called by the MAC framework to get statistics that have
53been scoped to the ring, indicated by
54.Fa rh .
55.Pp
56The set of statistics that the driver should check depends on the kind
57of ring that is in use.
58If the driver encounters an unknown statistic it should return
59.Er ENOTSUP .
60All the statistics should be values that are scoped to the ring itself.
61This is in contrast to the normal
62.Xr mc_getstat 9E
63entry point, which has statistics for the entire device.
64Other than the scoping, the statistics listed below have the same
65meaning as they do in the
66.Sx STATISTICS
67section of
68.Xr mac 9E .
69See
70.Xr mac 9E
71for more details of those statistics.
72.Pp
73Receive rings should support the following statistics:
74.Bl -bullet
75.It
76.Dv MAC_STAT_IPACKETS
77.It
78.Dv MAC_STAT_RBYTES
79.El
80.Pp
81Transmit rings should support the following statitics:
82.Bl -bullet
83.It
84.Dv MAC_STAT_OBYTES
85.It
86.Dv MAC_STAT_OPACKETS
87.El
88.Sh EXAMPLES
89The following example shows how a driver might structure its
90.Fn mri_stat
91entry point.
92.Bd -literal
93#include <sys/mac_provider.h>
94
95/*
96 * Note, this example merely shows the structure of the function. For
97 * the purpose of this example, we assume that we have a per-ring
98 * structure which has members that indicate its stats and that it has a
99 * lock which is used to serialize access to this data.
100 */
101
102static int
103example_tx_ring_stat(mac_ring_driver_t rh, uint_t stat, uint64_t *val)
104{
105	example_tx_ring_t *etrp = arg;
106
107	mutex_enter(&etrp->etrp_lock);
108	switch (stat) {
109	case MAC_STAT_OBYTES:
110		*val = etrp->etrp_stats.eps_obytes;
111		break;
112	case MAC_STAT_OPACKETS:
113		*val = etrp->etrp_stats.eps_opackets;
114		break;
115	default:
116		mutex_exit(&etrp->etrp_lock);
117		return (ENOTSUP);
118	}
119	mutex_exit(&etrp->etrp_lock);
120
121	return (0);
122}
123
124static int
125example_rx_ring_stat(mac_ring_driver_t rh, uint_t stat, uint64_t *val)
126{
127	example_rx_ring_t *errp = arg;
128
129	mutex_enter(&errp->errp_lock);
130	switch (stat) {
131	case MAC_STAT_RBYTES:
132		*val = errp->errp_stats.eps_ibytes;
133		break;
134	case MAC_STAT_IPACKETS:
135		*val = errp->errp_stats.eps_ipackets;
136		break;
137	default:
138		mutex_exit(&errp->errp_lock);
139		return (ENOTSUP);
140	}
141	mutex_exit(&errp->errp_lock);
142
143	return (0);
144}
145.Ed
146.Sh ERRORS
147The device driver may return one of the following errors.
148While this list is not intended to be exhaustive, it is recommend to use
149one of these if possible.
150.Bl -tag -width Er
151.It Er ENOTSUP
152The specified statistic is unknown, unsupported, or unimplemented.
153.It Er EIO
154A transport or DMA FM related error occurred while trying to sync data
155from the device.
156.It Er ECANCELLED
157The device is not currently in a state where it can currently service
158the request.
159.El
160.Sh SEE ALSO
161.Xr mac 9E ,
162.Xr mac_capab_rings 9E ,
163.Xr mc_getstat 9E ,
164.Xr mr_rget 9E ,
165.Xr mac_ring_info 9S
166