Re: [dpdk-dev] [PATCH v2 3/4] examples/power: allow vms to use lcores over 63

[Burakov, Anatoly]

On 14-Dec-18 11:49 AM, David Hunt wrote:
Extending the functionality to allow vms to power manage cores beyond 63.
Signed-off-by: David Hunt <david.h...@intel.com>
---
  examples/vm_power_manager/channel_manager.c | 74 +++++++++------------
  examples/vm_power_manager/channel_manager.h | 30 ++-------
  examples/vm_power_manager/channel_monitor.c | 56 ++++++----------
  examples/vm_power_manager/vm_power_cli.c    |  4 +-
  4 files changed, 57 insertions(+), 107 deletions(-)

diff --git a/examples/vm_power_manager/channel_manager.c 
b/examples/vm_power_manager/channel_manager.c
index 71f4a0ccf..8756b53b8 100644
--- a/examples/vm_power_manager/channel_manager.c
+++ b/examples/vm_power_manager/channel_manager.c
@@ -49,7 +49,7 @@ static bool global_hypervisor_available;
   */
  struct virtual_machine_info {
        char name[CHANNEL_MGR_MAX_NAME_LEN];
-       rte_atomic64_t pcpu_mask[CHANNEL_CMDS_MAX_CPUS];
+       uint16_t pcpu_map[CHANNEL_CMDS_MAX_CPUS];
        struct channel_info *channels[CHANNEL_CMDS_MAX_VM_CHANNELS];
        char channel_mask[POWER_MGR_MAX_CPUS];
        uint8_t num_channels;
@@ -79,7 +79,6 @@ update_pcpus_mask(struct virtual_machine_info *vm_info)
        virVcpuInfoPtr cpuinfo;
        unsigned i, j;
        int n_vcpus;
-       uint64_t mask;
  
  	memset(global_cpumaps, 0, CHANNEL_CMDS_MAX_CPUS*global_maplen);
  
@@ -120,26 +119,23 @@ update_pcpus_mask(struct virtual_machine_info *vm_info)
                vm_info->info.nrVirtCpu = n_vcpus;
        }
        for (i = 0; i < vm_info->info.nrVirtCpu; i++) {
-               mask = 0;
                for (j = 0; j < global_n_host_cpus; j++) {
-                       if (VIR_CPU_USABLE(global_cpumaps, global_maplen, i, j) 
> 0) {
-                               mask |= 1ULL << j;
-                       }
+                       if (VIR_CPU_USABLE(global_cpumaps,
+                                       global_maplen, i, j) <= 0)
+                               continue;
+                       rte_spinlock_lock(&(vm_info->config_spinlock));
+                       vm_info->pcpu_map[i] = j;
+                       rte_spinlock_unlock(&(vm_info->config_spinlock));

This is not an equivalent replacement, because something can happen 
inbetween the unlock and subsequent lock. There's no need to lock-unlock 
it on every iteration anyway - just lock it before the for (i = 0...) 
and unlock it right before return.

                }
-               rte_atomic64_set(&vm_info->pcpu_mask[i], mask);
        }
        return 0;
  }
  
  int
-set_pcpus_mask(char *vm_name, unsigned int vcpu, char *core_mask)
+set_pcpu(char *vm_name, unsigned int vcpu, unsigned int pcpu)
  {

<snip>

--- a/examples/vm_power_manager/channel_manager.h
+++ b/examples/vm_power_manager/channel_manager.h
@@ -40,7 +40,6 @@ struct sockaddr_un _sockaddr_un;
  #define MAX_CLIENTS 64
  #define MAX_VCPUS 20
  
-
  struct libvirt_vm_info {

Unintended whitespace change?

        const char *vm_name;
        unsigned int pcpus[MAX_VCPUS];
@@ -82,7 +81,7 @@ struct channel_info {
  struct vm_info {
        char name[CHANNEL_MGR_MAX_NAME_LEN];          /**< VM name */
        enum vm_status status;                        /**< libvirt status */

--
Thanks,
Anatoly