From 6640b5df1a38801be6d0595c8cd2177d968d7ee0 Mon Sep 17 00:00:00 2001 From: Saurabh Sengar Date: Fri, 27 May 2022 00:43:59 -0700 Subject: [PATCH] Drivers: hv: vmbus: Don't assign VMbus channel interrupts to isolated CPUs MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit When initially assigning a VMbus channel interrupt to a CPU, don’t choose a managed IRQ isolated CPU (as specified on the kernel boot line with parameter 'isolcpus=managed_irq,<#cpu>'). Also, when using sysfs to change the CPU that a VMbus channel will interrupt, don't allow changing to a managed IRQ isolated CPU. Signed-off-by: Saurabh Sengar Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/1653637439-23060-1-git-send-email-ssengar@linux.microsoft.com Signed-off-by: Wei Liu --- drivers/hv/channel_mgmt.c | 17 ++++++++++++----- drivers/hv/vmbus_drv.c | 4 ++++ 2 files changed, 16 insertions(+), 5 deletions(-) diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c index b60f134..280b529 100644 --- a/drivers/hv/channel_mgmt.c +++ b/drivers/hv/channel_mgmt.c @@ -21,6 +21,7 @@ #include #include #include +#include #include "hyperv_vmbus.h" @@ -728,16 +729,20 @@ static void init_vp_index(struct vmbus_channel *channel) u32 i, ncpu = num_online_cpus(); cpumask_var_t available_mask; struct cpumask *allocated_mask; + const struct cpumask *hk_mask = housekeeping_cpumask(HK_TYPE_MANAGED_IRQ); u32 target_cpu; int numa_node; if (!perf_chn || - !alloc_cpumask_var(&available_mask, GFP_KERNEL)) { + !alloc_cpumask_var(&available_mask, GFP_KERNEL) || + cpumask_empty(hk_mask)) { /* * If the channel is not a performance critical * channel, bind it to VMBUS_CONNECT_CPU. * In case alloc_cpumask_var() fails, bind it to * VMBUS_CONNECT_CPU. + * If all the cpus are isolated, bind it to + * VMBUS_CONNECT_CPU. */ channel->target_cpu = VMBUS_CONNECT_CPU; if (perf_chn) @@ -758,17 +763,19 @@ static void init_vp_index(struct vmbus_channel *channel) } allocated_mask = &hv_context.hv_numa_map[numa_node]; - if (cpumask_equal(allocated_mask, cpumask_of_node(numa_node))) { +retry: + cpumask_xor(available_mask, allocated_mask, cpumask_of_node(numa_node)); + cpumask_and(available_mask, available_mask, hk_mask); + + if (cpumask_empty(available_mask)) { /* * We have cycled through all the CPUs in the node; * reset the allocated map. */ cpumask_clear(allocated_mask); + goto retry; } - cpumask_xor(available_mask, allocated_mask, - cpumask_of_node(numa_node)); - target_cpu = cpumask_first(available_mask); cpumask_set_cpu(target_cpu, allocated_mask); diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 714d549..547ae33 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include @@ -1770,6 +1771,9 @@ static ssize_t target_cpu_store(struct vmbus_channel *channel, if (target_cpu >= nr_cpumask_bits) return -EINVAL; + if (!cpumask_test_cpu(target_cpu, housekeeping_cpumask(HK_TYPE_MANAGED_IRQ))) + return -EINVAL; + /* No CPUs should come up or down during this. */ cpus_read_lock(); -- 2.7.4