From 48dbe31a243d5fc7c07b7f03b48e95ec4696b118 Mon Sep 17 00:00:00 2001 From: James Morse Date: Fri, 2 Sep 2022 15:48:21 +0000 Subject: x86/resctrl: Add per-rmid arch private storage for overflow and chunks A renamed __rmid_read() is intended as the function that an architecture agnostic resctrl filesystem driver can use to read a value in bytes from a counter. Currently the function returns the MBM values in chunks directly from hardware. For bandwidth counters the resctrl filesystem uses this to calculate the number of bytes ever seen. MPAM's scaling of counters can be changed at runtime, reducing the resolution but increasing the range. When this is changed the prev_msr values need to be converted by the architecture code. Add an array for per-rmid private storage. The prev_msr and chunks values will move here to allow resctrl_arch_rmid_read() to always return the number of bytes read by this counter without assistance from the filesystem. The values are moved in later patches when the overflow and correction calls are moved into __rmid_read(). Signed-off-by: James Morse Signed-off-by: Borislav Petkov Reviewed-by: Jamie Iles Reviewed-by: Shaopeng Tan Reviewed-by: Reinette Chatre Tested-by: Xin Hao Tested-by: Shaopeng Tan Tested-by: Cristian Marussi Link: https://lore.kernel.org/r/20220902154829.30399-14-james.morse@arm.com --- arch/x86/kernel/cpu/resctrl/core.c | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) (limited to 'arch/x86/kernel/cpu/resctrl/core.c') diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c index 90ebb7d71af2..de62b0b87ced 100644 --- a/arch/x86/kernel/cpu/resctrl/core.c +++ b/arch/x86/kernel/cpu/resctrl/core.c @@ -413,6 +413,8 @@ static void setup_default_ctrlval(struct rdt_resource *r, u32 *dc) static void domain_free(struct rdt_hw_domain *hw_dom) { + kfree(hw_dom->arch_mbm_total); + kfree(hw_dom->arch_mbm_local); kfree(hw_dom->ctrl_val); kfree(hw_dom); } @@ -438,6 +440,34 @@ static int domain_setup_ctrlval(struct rdt_resource *r, struct rdt_domain *d) return 0; } +/** + * arch_domain_mbm_alloc() - Allocate arch private storage for the MBM counters + * @num_rmid: The size of the MBM counter array + * @hw_dom: The domain that owns the allocated arrays + */ +static int arch_domain_mbm_alloc(u32 num_rmid, struct rdt_hw_domain *hw_dom) +{ + size_t tsize; + + if (is_mbm_total_enabled()) { + tsize = sizeof(*hw_dom->arch_mbm_total); + hw_dom->arch_mbm_total = kcalloc(num_rmid, tsize, GFP_KERNEL); + if (!hw_dom->arch_mbm_total) + return -ENOMEM; + } + if (is_mbm_local_enabled()) { + tsize = sizeof(*hw_dom->arch_mbm_local); + hw_dom->arch_mbm_local = kcalloc(num_rmid, tsize, GFP_KERNEL); + if (!hw_dom->arch_mbm_local) { + kfree(hw_dom->arch_mbm_total); + hw_dom->arch_mbm_total = NULL; + return -ENOMEM; + } + } + + return 0; +} + /* * domain_add_cpu - Add a cpu to a resource's domain list. * @@ -487,6 +517,11 @@ static void domain_add_cpu(int cpu, struct rdt_resource *r) return; } + if (r->mon_capable && arch_domain_mbm_alloc(r->num_rmid, hw_dom)) { + domain_free(hw_dom); + return; + } + list_add_tail(&d->list, add_pos); err = resctrl_online_domain(r, d); -- cgit v1.2.3