Date: Mon, 13 May 2019 18:48:08 +0000 (UTC) From: Stephen Hurd <shurd@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-12@freebsd.org Subject: svn commit: r347542 - in stable/12: share/man/man4 sys/net Message-ID: <201905131848.x4DIm8hG054346@repo.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: shurd Date: Mon May 13 18:48:08 2019 New Revision: 347542 URL: https://svnweb.freebsd.org/changeset/base/347542 Log: MFC r346708: iflib: Better control over queue core assignment By default, cores are now assigned to queues in a sequential manner rather than all NICs starting at the first core. On a four-core system with two NICs each using two queue pairs, the nic:queue -> core mapping has changed from this: 0:0 -> 0, 0:1 -> 1 1:0 -> 0, 1:1 -> 1 To this: 0:0 -> 0, 0:1 -> 1 1:0 -> 2, 1:1 -> 3 Additionally, a device can now be configured to use separate cores for TX and RX queues. Two new tunables have been added, dev.X.Y.iflib.separate_txrx and dev.X.Y.iflib.core_offset. If core_offset is set, the NIC is not part of the auto-assigned sequence. Reviewed by: marius Sponsored by: Limelight Networks Differential Revision: https://reviews.freebsd.org/D20029 Modified: stable/12/share/man/man4/iflib.4 stable/12/sys/net/iflib.c Directory Properties: stable/12/ (props changed) Modified: stable/12/share/man/man4/iflib.4 ============================================================================== --- stable/12/share/man/man4/iflib.4 Mon May 13 18:40:01 2019 (r347541) +++ stable/12/share/man/man4/iflib.4 Mon May 13 18:48:08 2019 (r347542) @@ -55,6 +55,16 @@ If zero, the number of TX queues is derived from the n socket connected to the controller. .It Va disable_msix Disables MSI-X interrupts for the device. +.It Va core_offset +Specifies a starting core offset to assign queues to. +If the value is unspecified or 65535, cores are assigned sequentially across +controllers. +.It Va separate_txrx +Requests that RX and TX queues not be paired on the same core. +If this is zero or not set, an RX and TX queue pair will be assigned to each +core. +When set to a non-zero value, TX queues are assigned to cores following the +last RX queue. .El .Pp These Modified: stable/12/sys/net/iflib.c ============================================================================== --- stable/12/sys/net/iflib.c Mon May 13 18:40:01 2019 (r347541) +++ stable/12/sys/net/iflib.c Mon May 13 18:48:08 2019 (r347542) @@ -191,6 +191,9 @@ struct iflib_ctx { uint16_t ifc_sysctl_qs_eq_override; uint16_t ifc_sysctl_rx_budget; uint16_t ifc_sysctl_tx_abdicate; + uint16_t ifc_sysctl_core_offset; +#define CORE_OFFSET_UNSPECIFIED 0xffff + uint8_t ifc_sysctl_separate_txrx; qidx_t ifc_sysctl_ntxds[8]; qidx_t ifc_sysctl_nrxds[8]; @@ -728,6 +731,18 @@ static void iflib_free_intr_mem(if_ctx_t ctx); static struct mbuf * iflib_fixup_rx(struct mbuf *m); #endif +static SLIST_HEAD(cpu_offset_list, cpu_offset) cpu_offsets = + SLIST_HEAD_INITIALIZER(cpu_offsets); +struct cpu_offset { + SLIST_ENTRY(cpu_offset) entries; + cpuset_t set; + unsigned int refcount; + uint16_t offset; +}; +static struct mtx cpu_offset_mtx; +MTX_SYSINIT(iflib_cpu_offset, &cpu_offset_mtx, "iflib_cpu_offset lock", + MTX_DEF); + NETDUMP_DEFINE(iflib); #ifdef DEV_NETMAP @@ -4401,6 +4416,71 @@ iflib_reset_qvalues(if_ctx_t ctx) } } +static uint16_t +get_ctx_core_offset(if_ctx_t ctx) +{ + if_softc_ctx_t scctx = &ctx->ifc_softc_ctx; + struct cpu_offset *op; + uint16_t qc; + uint16_t ret = ctx->ifc_sysctl_core_offset; + + if (ret != CORE_OFFSET_UNSPECIFIED) + return (ret); + + if (ctx->ifc_sysctl_separate_txrx) + qc = scctx->isc_ntxqsets + scctx->isc_nrxqsets; + else + qc = max(scctx->isc_ntxqsets, scctx->isc_nrxqsets); + + mtx_lock(&cpu_offset_mtx); + SLIST_FOREACH(op, &cpu_offsets, entries) { + if (CPU_CMP(&ctx->ifc_cpus, &op->set) == 0) { + ret = op->offset; + op->offset += qc; + MPASS(op->refcount < UINT_MAX); + op->refcount++; + break; + } + } + if (ret == CORE_OFFSET_UNSPECIFIED) { + ret = 0; + op = malloc(sizeof(struct cpu_offset), M_IFLIB, + M_NOWAIT | M_ZERO); + if (op == NULL) { + device_printf(ctx->ifc_dev, + "allocation for cpu offset failed.\n"); + } else { + op->offset = qc; + op->refcount = 1; + CPU_COPY(&ctx->ifc_cpus, &op->set); + SLIST_INSERT_HEAD(&cpu_offsets, op, entries); + } + } + mtx_unlock(&cpu_offset_mtx); + + return (ret); +} + +static void +unref_ctx_core_offset(if_ctx_t ctx) +{ + struct cpu_offset *op, *top; + + mtx_lock(&cpu_offset_mtx); + SLIST_FOREACH_SAFE(op, &cpu_offsets, entries, top) { + if (CPU_CMP(&ctx->ifc_cpus, &op->set) == 0) { + MPASS(op->refcount > 0); + op->refcount--; + if (op->refcount == 0) { + SLIST_REMOVE(&cpu_offsets, op, cpu_offset, entries); + free(op, M_IFLIB); + } + break; + } + } + mtx_unlock(&cpu_offset_mtx); +} + int iflib_device_register(device_t dev, void *sc, if_shared_ctx_t sctx, if_ctx_t *ctxp) { @@ -4551,6 +4631,11 @@ iflib_device_register(device_t dev, void *sc, if_share goto fail_queues; /* + * Now that we know how many queues there are, get the core offset. + */ + ctx->ifc_sysctl_core_offset = get_ctx_core_offset(ctx); + + /* * Group taskqueues aren't properly set up until SMP is started, * so we disable interrupts until we can handle them post * SI_SUB_SMP. @@ -4971,6 +5056,7 @@ iflib_device_deregister(if_ctx_t ctx) iflib_rx_structures_free(ctx); if (ctx->ifc_flags & IFC_SC_ALLOCATED) free(ctx->ifc_softc, M_IFLIB); + unref_ctx_core_offset(ctx); STATE_LOCK_DESTROY(ctx); free(ctx, M_IFLIB); return (0); @@ -5589,7 +5675,7 @@ find_child_with_core(int cpu, struct cpu_group *grp) * Find the nth "close" core to the specified core * "close" is defined as the deepest level that shares * at least an L2 cache. With threads, this will be - * threads on the same core. If the sahred cache is L3 + * threads on the same core. If the shared cache is L3 * or higher, simply returns the same core. */ static int @@ -5671,10 +5757,12 @@ static inline int iflib_irq_set_affinity(if_ctx_t ctx, int irq, iflib_intr_type_t type, int qid, struct grouptask *gtask, struct taskqgroup *tqg, void *uniq, const char *name) { - int cpuid; - int err, tid; + int co, cpuid, err, tid; - cpuid = find_nth(ctx, qid); + co = ctx->ifc_sysctl_core_offset; + if (ctx->ifc_sysctl_separate_txrx && type == IFLIB_INTR_TX) + co += ctx->ifc_softc_ctx.isc_nrxqsets; + cpuid = find_nth(ctx, qid + co); tid = get_core_offset(ctx, type, qid); MPASS(tid >= 0); cpuid = find_close_core(cpuid, tid); @@ -6264,6 +6352,13 @@ iflib_add_device_sysctl_pre(if_ctx_t ctx) SYSCTL_ADD_U16(ctx_list, oid_list, OID_AUTO, "tx_abdicate", CTLFLAG_RWTUN, &ctx->ifc_sysctl_tx_abdicate, 0, "cause tx to abdicate instead of running to completion"); + ctx->ifc_sysctl_core_offset = CORE_OFFSET_UNSPECIFIED; + SYSCTL_ADD_U16(ctx_list, oid_list, OID_AUTO, "core_offset", + CTLFLAG_RDTUN, &ctx->ifc_sysctl_core_offset, 0, + "offset to start using cores at"); + SYSCTL_ADD_U8(ctx_list, oid_list, OID_AUTO, "separate_txrx", + CTLFLAG_RDTUN, &ctx->ifc_sysctl_separate_txrx, 0, + "use separate cores for TX and RX"); /* XXX change for per-queue sizes */ SYSCTL_ADD_PROC(ctx_list, oid_list, OID_AUTO, "override_ntxds",
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201905131848.x4DIm8hG054346>