From dfe9674b04ff6b819f9105650a008d164d81725e Mon Sep 17 00:00:00 2001 From: Reinette Chatre Date: Fri, 22 Jun 2018 15:42:17 -0700 Subject: [PATCH] x86/intel_rdt: Enable entering of pseudo-locksetup mode The user can request entering pseudo-locksetup mode by writing "pseudo-locksetup" to the mode file. Act on this request as well as support switching from a pseudo-locksetup mode (before pseudo-locked mode was entered). It is not supported to modify the mode once pseudo-locked mode has been entered. The schemata reflects the new mode by adding "uninitialized" to all resources. The size resctrl file reports zero for all cache domains in support of the uninitialized nature. Since there are no users of this class of service its allocations can be ignored when searching for appropriate default allocations for new resource groups. For the same reason resource groups in pseudo-locksetup mode are not considered when testing if new resource groups may overlap. Signed-off-by: Reinette Chatre Signed-off-by: Thomas Gleixner Cc: fenghua.yu@intel.com Cc: tony.luck@intel.com Cc: vikas.shivappa@linux.intel.com Cc: gavin.hindman@intel.com Cc: jithu.joseph@intel.com Cc: dave.hansen@intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/56f553334708022903c296284e62db3bbc1ff150.1529706536.git.reinette.chatre@intel.com --- arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c | 16 +++++--- arch/x86/kernel/cpu/intel_rdt_rdtgroup.c | 41 ++++++++++++++++++--- 2 files changed, 47 insertions(+), 10 deletions(-) diff --git a/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c b/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c index bc79396c5dad..1ed273220ffa 100644 --- a/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c +++ b/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c @@ -156,7 +156,8 @@ int parse_cbm(void *_data, struct rdt_resource *r, struct rdt_domain *d) } if (rdtgroup_cbm_overlaps(r, d, cbm_val, rdtgrp->closid, false)) { - if (rdtgrp->mode == RDT_MODE_EXCLUSIVE) { + if (rdtgrp->mode == RDT_MODE_EXCLUSIVE || + rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) { rdt_last_cmd_printf("overlaps with other group\n"); return -EINVAL; } @@ -356,10 +357,15 @@ int rdtgroup_schemata_show(struct kernfs_open_file *of, rdtgrp = rdtgroup_kn_lock_live(of->kn); if (rdtgrp) { - closid = rdtgrp->closid; - for_each_alloc_enabled_rdt_resource(r) { - if (closid < r->num_closid) - show_doms(s, r, closid); + if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) { + for_each_alloc_enabled_rdt_resource(r) + seq_printf(s, "%s:uninitialized\n", r->name); + } else { + closid = rdtgrp->closid; + for_each_alloc_enabled_rdt_resource(r) { + if (closid < r->num_closid) + show_doms(s, r, closid); + } } } else { ret = -ENOENT; diff --git a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c index 013cbfedc753..bd4e2de303dc 100644 --- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c +++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c @@ -974,9 +974,10 @@ bool rdtgroup_cbm_overlaps(struct rdt_resource *r, struct rdt_domain *d, ctrl = d->ctrl_val; for (i = 0; i < r->num_closid; i++, ctrl++) { ctrl_b = (unsigned long *)ctrl; - if (closid_allocated(i) && i != closid) { + mode = rdtgroup_mode_by_closid(i); + if (closid_allocated(i) && i != closid && + mode != RDT_MODE_PSEUDO_LOCKSETUP) { if (bitmap_intersects(cbm, ctrl_b, r->cache.cbm_len)) { - mode = rdtgroup_mode_by_closid(i); if (exclusive) { if (mode == RDT_MODE_EXCLUSIVE) return true; @@ -1046,10 +1047,24 @@ static ssize_t rdtgroup_mode_write(struct kernfs_open_file *of, mode = rdtgrp->mode; if ((!strcmp(buf, "shareable") && mode == RDT_MODE_SHAREABLE) || - (!strcmp(buf, "exclusive") && mode == RDT_MODE_EXCLUSIVE)) + (!strcmp(buf, "exclusive") && mode == RDT_MODE_EXCLUSIVE) || + (!strcmp(buf, "pseudo-locksetup") && + mode == RDT_MODE_PSEUDO_LOCKSETUP) || + (!strcmp(buf, "pseudo-locked") && mode == RDT_MODE_PSEUDO_LOCKED)) goto out; + if (mode == RDT_MODE_PSEUDO_LOCKED) { + rdt_last_cmd_printf("cannot change pseudo-locked group\n"); + ret = -EINVAL; + goto out; + } + if (!strcmp(buf, "shareable")) { + if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) { + ret = rdtgroup_locksetup_exit(rdtgrp); + if (ret) + goto out; + } rdtgrp->mode = RDT_MODE_SHAREABLE; } else if (!strcmp(buf, "exclusive")) { if (!rdtgroup_mode_test_exclusive(rdtgrp)) { @@ -1057,7 +1072,17 @@ static ssize_t rdtgroup_mode_write(struct kernfs_open_file *of, ret = -EINVAL; goto out; } + if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) { + ret = rdtgroup_locksetup_exit(rdtgrp); + if (ret) + goto out; + } rdtgrp->mode = RDT_MODE_EXCLUSIVE; + } else if (!strcmp(buf, "pseudo-locksetup")) { + ret = rdtgroup_locksetup_enter(rdtgrp); + if (ret) + goto out; + rdtgrp->mode = RDT_MODE_PSEUDO_LOCKSETUP; } else { rdt_last_cmd_printf("unknown/unsupported mode\n"); ret = -EINVAL; @@ -1127,8 +1152,12 @@ static int rdtgroup_size_show(struct kernfs_open_file *of, list_for_each_entry(d, &r->domains, list) { if (sep) seq_putc(s, ';'); - cbm = d->ctrl_val[rdtgrp->closid]; - size = rdtgroup_cbm_to_size(r, d, cbm); + if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) { + size = 0; + } else { + cbm = d->ctrl_val[rdtgrp->closid]; + size = rdtgroup_cbm_to_size(r, d, cbm); + } seq_printf(s, "%d=%u", d->id, size); sep = true; } @@ -2277,6 +2306,8 @@ static int rdtgroup_init_alloc(struct rdtgroup *rdtgrp) for (i = 0; i < r->num_closid; i++, ctrl++) { if (closid_allocated(i) && i != closid) { mode = rdtgroup_mode_by_closid(i); + if (mode == RDT_MODE_PSEUDO_LOCKSETUP) + break; used_b |= *ctrl; if (mode == RDT_MODE_SHAREABLE) d->new_ctrl |= *ctrl; -- GitLab