| Message ID | 20201215074213.32652-1-maximmi@mellanox.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | David Ahern |
| Headers | show |
| Series | [iproute2-next] tc/htb: Hierarchical QoS hardware offload | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Guessing tree name failed - patch did not apply |
On Tue, 15 Dec 2020 09:42:08 +0200
Maxim Mikityanskiy <maximmi@mellanox.com> wrote:
> + print_uint(PRINT_ANY, "offload", " offload %d", !!tb[TCA_HTB_OFFLOAD]);
This is not the best way to represent a boolean flag in JSON.
Also it breaks the "output should be the same as command line" mantra.
My preference is json_null to indicate presence of a flag.
Something like:
if (tb[TCA_HTB_OFFLOAD])
print_null(PRINT_ANY, "offload", "offload", NULL);
On 2021-01-29 18:05, David Ahern wrote: > On 12/15/20 12:42 AM, Maxim Mikityanskiy wrote: >> This commit adds support for configuring HTB in offload mode. HTB >> offload eliminates the single qdisc lock in the datapath and offloads >> the algorithm to the NIC. The new 'offload' parameter is added to >> enable this mode: >> >> # tc qdisc replace dev eth0 root handle 1: htb offload >> >> Classes are created as usual, but filters should be moved to clsact for >> lock-free classification (filters attached to HTB itself are not >> supported in the offload mode): >> >> # tc filter add dev eth0 egress protocol ip flower dst_port 80 >> action skbedit priority 1:10 > > please add the dump in both stdout and json here. Do you mean to add example output to the commit message? >> >> Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com> >> --- >> include/uapi/linux/pkt_sched.h | 1 + >> tc/q_htb.c | 9 ++++++++- > > missing an update to man/man8/tc-htb.8 OK, I'll add. >> 2 files changed, 9 insertions(+), 1 deletion(-) >> >> diff --git a/include/uapi/linux/pkt_sched.h b/include/uapi/linux/pkt_sched.h >> index 9e7c2c60..79a699f1 100644 >> --- a/include/uapi/linux/pkt_sched.h >> +++ b/include/uapi/linux/pkt_sched.h >> @@ -434,6 +434,7 @@ enum { >> TCA_HTB_RATE64, >> TCA_HTB_CEIL64, >> TCA_HTB_PAD, >> + TCA_HTB_OFFLOAD, >> __TCA_HTB_MAX, >> }; >> >> diff --git a/tc/q_htb.c b/tc/q_htb.c >> index c609e974..fd11dad6 100644 >> --- a/tc/q_htb.c >> +++ b/tc/q_htb.c >> @@ -30,11 +30,12 @@ >> static void explain(void) >> { >> fprintf(stderr, "Usage: ... qdisc add ... htb [default N] [r2q N]\n" >> - " [direct_qlen P]\n" >> + " [direct_qlen P] [offload]\n" >> " default minor id of class to which unclassified packets are sent {0}\n" >> " r2q DRR quantums are computed as rate in Bps/r2q {10}\n" >> " debug string of 16 numbers each 0-3 {0}\n\n" >> " direct_qlen Limit of the direct queue {in packets}\n" >> + " offload hardware offload\n" > > why 'offload hardware offload'? does not make sense to me and "offload" is a new parameter, and "hardware offload" is the description, just like the other parameters above. > you don't > reference hardware below. Where should I reference it? > > > >> "... class add ... htb rate R1 [burst B1] [mpu B] [overhead O]\n" >> " [prio P] [slot S] [pslot PS]\n" >> " [ceil R2] [cburst B2] [mtu MTU] [quantum Q]\n" >> @@ -68,6 +69,7 @@ static int htb_parse_opt(struct qdisc_util *qu, int argc, >> }; >> struct rtattr *tail; >> unsigned int i; char *p; >> + bool offload = false; >> >> while (argc > 0) { >> if (matches(*argv, "r2q") == 0) { >> @@ -91,6 +93,8 @@ static int htb_parse_opt(struct qdisc_util *qu, int argc, >> if (get_u32(&direct_qlen, *argv, 10)) { >> explain1("direct_qlen"); return -1; >> } >> + } else if (matches(*argv, "offload") == 0) { >> + offload = true; >> } else { >> fprintf(stderr, "What is \"%s\"?\n", *argv); >> explain(); >> @@ -103,6 +107,8 @@ static int htb_parse_opt(struct qdisc_util *qu, int argc, >> if (direct_qlen != ~0U) >> addattr_l(n, 2024, TCA_HTB_DIRECT_QLEN, >> &direct_qlen, sizeof(direct_qlen)); >> + if (offload) >> + addattr(n, 2024, TCA_HTB_OFFLOAD); >> addattr_nest_end(n, tail); >> return 0; >> } >> @@ -344,6 +350,7 @@ static int htb_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt) >> print_uint(PRINT_ANY, "direct_qlen", " direct_qlen %u", >> direct_qlen); >> } >> + print_uint(PRINT_ANY, "offload", " offload %d", !!tb[TCA_HTB_OFFLOAD]); >> return 0; >> } >> >> >
On 2/2/21 4:46 AM, Maxim Mikityanskiy wrote: > On 2021-01-29 18:05, David Ahern wrote: >> On 12/15/20 12:42 AM, Maxim Mikityanskiy wrote: >>> This commit adds support for configuring HTB in offload mode. HTB >>> offload eliminates the single qdisc lock in the datapath and offloads >>> the algorithm to the NIC. The new 'offload' parameter is added to >>> enable this mode: >>> >>> # tc qdisc replace dev eth0 root handle 1: htb offload >>> >>> Classes are created as usual, but filters should be moved to clsact for >>> lock-free classification (filters attached to HTB itself are not >>> supported in the offload mode): >>> >>> # tc filter add dev eth0 egress protocol ip flower dst_port 80 >>> action skbedit priority 1:10 >> >> please add the dump in both stdout and json here. > > Do you mean to add example output to the commit message? yes. >>> diff --git a/tc/q_htb.c b/tc/q_htb.c >>> index c609e974..fd11dad6 100644 >>> --- a/tc/q_htb.c >>> +++ b/tc/q_htb.c >>> @@ -30,11 +30,12 @@ >>> static void explain(void) >>> { >>> fprintf(stderr, "Usage: ... qdisc add ... htb [default N] [r2q >>> N]\n" >>> - " [direct_qlen P]\n" >>> + " [direct_qlen P] [offload]\n" >>> " default minor id of class to which unclassified packets >>> are sent {0}\n" >>> " r2q DRR quantums are computed as rate in Bps/r2q >>> {10}\n" >>> " debug string of 16 numbers each 0-3 {0}\n\n" >>> " direct_qlen Limit of the direct queue {in packets}\n" >>> + " offload hardware offload\n" >> >> why 'offload hardware offload'? does not make sense to me and > > "offload" is a new parameter, and "hardware offload" is the description, > just like the other parameters above. > >> you don't >> reference hardware below. > > Where should I reference it? I see now. More words are needed to make it clear 'hardware offload' is the explanation of offload. As it is, the words run together as 'offload hardware offload' which is the source of my confusion.
diff --git a/include/uapi/linux/pkt_sched.h b/include/uapi/linux/pkt_sched.h index 9e7c2c60..79a699f1 100644 --- a/include/uapi/linux/pkt_sched.h +++ b/include/uapi/linux/pkt_sched.h @@ -434,6 +434,7 @@ enum { TCA_HTB_RATE64, TCA_HTB_CEIL64, TCA_HTB_PAD, + TCA_HTB_OFFLOAD, __TCA_HTB_MAX, }; diff --git a/tc/q_htb.c b/tc/q_htb.c index c609e974..fd11dad6 100644 --- a/tc/q_htb.c +++ b/tc/q_htb.c @@ -30,11 +30,12 @@ static void explain(void) { fprintf(stderr, "Usage: ... qdisc add ... htb [default N] [r2q N]\n" - " [direct_qlen P]\n" + " [direct_qlen P] [offload]\n" " default minor id of class to which unclassified packets are sent {0}\n" " r2q DRR quantums are computed as rate in Bps/r2q {10}\n" " debug string of 16 numbers each 0-3 {0}\n\n" " direct_qlen Limit of the direct queue {in packets}\n" + " offload hardware offload\n" "... class add ... htb rate R1 [burst B1] [mpu B] [overhead O]\n" " [prio P] [slot S] [pslot PS]\n" " [ceil R2] [cburst B2] [mtu MTU] [quantum Q]\n" @@ -68,6 +69,7 @@ static int htb_parse_opt(struct qdisc_util *qu, int argc, }; struct rtattr *tail; unsigned int i; char *p; + bool offload = false; while (argc > 0) { if (matches(*argv, "r2q") == 0) { @@ -91,6 +93,8 @@ static int htb_parse_opt(struct qdisc_util *qu, int argc, if (get_u32(&direct_qlen, *argv, 10)) { explain1("direct_qlen"); return -1; } + } else if (matches(*argv, "offload") == 0) { + offload = true; } else { fprintf(stderr, "What is \"%s\"?\n", *argv); explain(); @@ -103,6 +107,8 @@ static int htb_parse_opt(struct qdisc_util *qu, int argc, if (direct_qlen != ~0U) addattr_l(n, 2024, TCA_HTB_DIRECT_QLEN, &direct_qlen, sizeof(direct_qlen)); + if (offload) + addattr(n, 2024, TCA_HTB_OFFLOAD); addattr_nest_end(n, tail); return 0; } @@ -344,6 +350,7 @@ static int htb_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt) print_uint(PRINT_ANY, "direct_qlen", " direct_qlen %u", direct_qlen); } + print_uint(PRINT_ANY, "offload", " offload %d", !!tb[TCA_HTB_OFFLOAD]); return 0; }
This commit adds support for configuring HTB in offload mode. HTB offload eliminates the single qdisc lock in the datapath and offloads the algorithm to the NIC. The new 'offload' parameter is added to enable this mode: # tc qdisc replace dev eth0 root handle 1: htb offload Classes are created as usual, but filters should be moved to clsact for lock-free classification (filters attached to HTB itself are not supported in the offload mode): # tc filter add dev eth0 egress protocol ip flower dst_port 80 action skbedit priority 1:10 Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com> --- include/uapi/linux/pkt_sched.h | 1 + tc/q_htb.c | 9 ++++++++- 2 files changed, 9 insertions(+), 1 deletion(-)