Re: [Qemu-devel] [PATCH 2.12] spapr: replace numa_get_node() with lookup in pc-dimm list

[Igor Mammedov]

On Wed, 6 Dec 2017 11:14:06 +1100
David Gibson <address@hidden> wrote:

> On Tue, Dec 05, 2017 at 04:41:17PM +0100, Igor Mammedov wrote:
> > SPAPR is the last user of numa_get_node() and a bunch of
> > supporting code to maintain numa_info[x].addr list.
> > 
> > Get LMB node id from pc-dimm list, which allows to
> > remove ~80LOC maintaining dynamic address range
> > lookup list.
> > 
> > It also removes pc-dimm dependency on numa_[un]set_mem_node_id()
> > and makes pc-dimms a sole source of information about which
> > node it belongs to and removes duplicate data from global
> > numa_info.
> > 
> > Signed-off-by: Igor Mammedov <address@hidden>
> > ---
> > Beside making code simpler, my interest in simplification
> > lies in allowing calling parse_numa_opts() multiple times,
> > without complex cleanups in case NUMA config is changed
> > since startup.
> > 
> > PS:
> > build tested only
> > ---
> >  include/sysemu/numa.h | 10 ------
> >  hw/mem/pc-dimm.c      |  2 --
> >  hw/ppc/spapr.c        | 29 +++++++++++++++-
> >  numa.c                | 94 
> > ---------------------------------------------------
> >  4 files changed, 28 insertions(+), 107 deletions(-)  
> 
> Applied to ppc-for-2.12.
Thanks

> 
> It definitely seems like an improvement over what we have.  Looking
> back at the DIMM list from QMP in the loop seems a little roundabout
> though.  Maybe we'd be better stepping through the DIMMs, then
> stepping through the LMBs within each DIMM, rather than just stepping
> through the LMBs directly.
Surely that would be better, maybe someone from ppc side would take care
of it.

> 
> 
> > 
> > diff --git a/include/sysemu/numa.h b/include/sysemu/numa.h
> > index 5c6df28..b354521 100644
> > --- a/include/sysemu/numa.h
> > +++ b/include/sysemu/numa.h
> > @@ -10,17 +10,10 @@
> >  extern int nb_numa_nodes;   /* Number of NUMA nodes */
> >  extern bool have_numa_distance;
> >  
> > -struct numa_addr_range {
> > -    ram_addr_t mem_start;
> > -    ram_addr_t mem_end;
> > -    QLIST_ENTRY(numa_addr_range) entry;
> > -};
> > -
> >  struct node_info {
> >      uint64_t node_mem;
> >      struct HostMemoryBackend *node_memdev;
> >      bool present;
> > -    QLIST_HEAD(, numa_addr_range) addr; /* List to store address ranges */
> >      uint8_t distance[MAX_NODES];
> >  };
> >  
> > @@ -33,9 +26,6 @@ extern NodeInfo numa_info[MAX_NODES];
> >  void parse_numa_opts(MachineState *ms);
> >  void query_numa_node_mem(NumaNodeMem node_mem[]);
> >  extern QemuOptsList qemu_numa_opts;
> > -void numa_set_mem_node_id(ram_addr_t addr, uint64_t size, uint32_t node);
> > -void numa_unset_mem_node_id(ram_addr_t addr, uint64_t size, uint32_t node);
> > -uint32_t numa_get_node(ram_addr_t addr, Error **errp);
> >  void numa_legacy_auto_assign_ram(MachineClass *mc, NodeInfo *nodes,
> >                                   int nb_nodes, ram_addr_t size);
> >  void numa_default_auto_assign_ram(MachineClass *mc, NodeInfo *nodes,
> > diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c
> > index 66eace5..6e74b61 100644
> > --- a/hw/mem/pc-dimm.c
> > +++ b/hw/mem/pc-dimm.c
> > @@ -109,7 +109,6 @@ void pc_dimm_memory_plug(DeviceState *dev, 
> > MemoryHotplugState *hpms,
> >  
> >      memory_region_add_subregion(&hpms->mr, addr - hpms->base, mr);
> >      vmstate_register_ram(vmstate_mr, dev);
> > -    numa_set_mem_node_id(addr, memory_region_size(mr), dimm->node);
> >  
> >  out:
> >      error_propagate(errp, local_err);
> > @@ -122,7 +121,6 @@ void pc_dimm_memory_unplug(DeviceState *dev, 
> > MemoryHotplugState *hpms,
> >      PCDIMMDeviceClass *ddc = PC_DIMM_GET_CLASS(dimm);
> >      MemoryRegion *vmstate_mr = ddc->get_vmstate_memory_region(dimm);
> >  
> > -    numa_unset_mem_node_id(dimm->addr, memory_region_size(mr), dimm->node);
> >      memory_region_del_subregion(&hpms->mr, mr);
> >      vmstate_unregister_ram(vmstate_mr, dev);
> >  }
> > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> > index 9efddea..8de0b5b 100644
> > --- a/hw/ppc/spapr.c
> > +++ b/hw/ppc/spapr.c
> > @@ -641,6 +641,26 @@ static void spapr_populate_cpus_dt_node(void *fdt, 
> > sPAPRMachineState *spapr)
> >  
> >  }
> >  
> > +static uint32_t spapr_pc_dimm_node(MemoryDeviceInfoList *list, ram_addr_t 
> > addr)
> > +{
> > +    MemoryDeviceInfoList *info;
> > +
> > +    for (info = list; info; info = info->next) {
> > +        MemoryDeviceInfo *value = info->value;
> > +
> > +        if (value && value->type == MEMORY_DEVICE_INFO_KIND_DIMM) {
> > +            PCDIMMDeviceInfo *pcdimm_info = value->u.dimm.data;
> > +
> > +            if (pcdimm_info->addr >= addr &&
> > +                addr < (pcdimm_info->addr + pcdimm_info->size)) {
> > +                return pcdimm_info->node;
> > +            }
> > +        }
> > +    }
> > +
> > +    return -1;
> > +}
> > +
> >  /*
> >   * Adds ibm,dynamic-reconfiguration-memory node.
> >   * Refer to docs/specs/ppc-spapr-hotplug.txt for the documentation
> > @@ -658,6 +678,7 @@ static int 
> > spapr_populate_drconf_memory(sPAPRMachineState *spapr, void *fdt)
> >                         lmb_size;
> >      uint32_t *int_buf, *cur_index, buf_len;
> >      int nr_nodes = nb_numa_nodes ? nb_numa_nodes : 1;
> > +    MemoryDeviceInfoList *dimms = NULL;
> >  
> >      /*
> >       * Don't create the node if there is no hotpluggable memory
> > @@ -692,6 +713,11 @@ static int 
> > spapr_populate_drconf_memory(sPAPRMachineState *spapr, void *fdt)
> >          goto out;
> >      }
> >  
> > +    if (hotplug_lmb_start) {
> > +        MemoryDeviceInfoList **prev = &dimms;
> > +        qmp_pc_dimm_device_list(qdev_get_machine(), &prev);
> > +    }
> > +
> >      /* ibm,dynamic-memory */
> >      int_buf[0] = cpu_to_be32(nr_lmbs);
> >      cur_index++;
> > @@ -709,7 +735,7 @@ static int 
> > spapr_populate_drconf_memory(sPAPRMachineState *spapr, void *fdt)
> >              dynamic_memory[1] = cpu_to_be32(addr & 0xffffffff);
> >              dynamic_memory[2] = cpu_to_be32(spapr_drc_index(drc));
> >              dynamic_memory[3] = cpu_to_be32(0); /* reserved */
> > -            dynamic_memory[4] = cpu_to_be32(numa_get_node(addr, NULL));
> > +            dynamic_memory[4] = cpu_to_be32(spapr_pc_dimm_node(dimms, 
> > addr));
> >              if (memory_region_present(get_system_memory(), addr)) {
> >                  dynamic_memory[5] = cpu_to_be32(SPAPR_LMB_FLAGS_ASSIGNED);
> >              } else {
> > @@ -732,6 +758,7 @@ static int 
> > spapr_populate_drconf_memory(sPAPRMachineState *spapr, void *fdt)
> >  
> >          cur_index += SPAPR_DR_LMB_LIST_ENTRY_SIZE;
> >      }
> > +    qapi_free_MemoryDeviceInfoList(dimms);
> >      ret = fdt_setprop(fdt, offset, "ibm,dynamic-memory", int_buf, buf_len);
> >      if (ret < 0) {
> >          goto out;
> > diff --git a/numa.c b/numa.c
> > index 7151b24..98fa9a4 100644
> > --- a/numa.c
> > +++ b/numa.c
> > @@ -55,92 +55,6 @@ int nb_numa_nodes;
> >  bool have_numa_distance;
> >  NodeInfo numa_info[MAX_NODES];
> >  
> > -void numa_set_mem_node_id(ram_addr_t addr, uint64_t size, uint32_t node)
> > -{
> > -    struct numa_addr_range *range;
> > -
> > -    /*
> > -     * Memory-less nodes can come here with 0 size in which case,
> > -     * there is nothing to do.
> > -     */
> > -    if (!size) {
> > -        return;
> > -    }
> > -
> > -    range = g_malloc0(sizeof(*range));
> > -    range->mem_start = addr;
> > -    range->mem_end = addr + size - 1;
> > -    QLIST_INSERT_HEAD(&numa_info[node].addr, range, entry);
> > -}
> > -
> > -void numa_unset_mem_node_id(ram_addr_t addr, uint64_t size, uint32_t node)
> > -{
> > -    struct numa_addr_range *range, *next;
> > -
> > -    QLIST_FOREACH_SAFE(range, &numa_info[node].addr, entry, next) {
> > -        if (addr == range->mem_start && (addr + size - 1) == 
> > range->mem_end) {
> > -            QLIST_REMOVE(range, entry);
> > -            g_free(range);
> > -            return;
> > -        }
> > -    }
> > -}
> > -
> > -static void numa_set_mem_ranges(void)
> > -{
> > -    int i;
> > -    ram_addr_t mem_start = 0;
> > -
> > -    /*
> > -     * Deduce start address of each node and use it to store
> > -     * the address range info in numa_info address range list
> > -     */
> > -    for (i = 0; i < nb_numa_nodes; i++) {
> > -        numa_set_mem_node_id(mem_start, numa_info[i].node_mem, i);
> > -        mem_start += numa_info[i].node_mem;
> > -    }
> > -}
> > -
> > -/*
> > - * Check if @addr falls under NUMA @node.
> > - */
> > -static bool numa_addr_belongs_to_node(ram_addr_t addr, uint32_t node)
> > -{
> > -    struct numa_addr_range *range;
> > -
> > -    QLIST_FOREACH(range, &numa_info[node].addr, entry) {
> > -        if (addr >= range->mem_start && addr <= range->mem_end) {
> > -            return true;
> > -        }
> > -    }
> > -    return false;
> > -}
> > -
> > -/*
> > - * Given an address, return the index of the NUMA node to which the
> > - * address belongs to.
> > - */
> > -uint32_t numa_get_node(ram_addr_t addr, Error **errp)
> > -{
> > -    uint32_t i;
> > -
> > -    /* For non NUMA configurations, check if the addr falls under node 0 */
> > -    if (!nb_numa_nodes) {
> > -        if (numa_addr_belongs_to_node(addr, 0)) {
> > -            return 0;
> > -        }
> > -    }
> > -
> > -    for (i = 0; i < nb_numa_nodes; i++) {
> > -        if (numa_addr_belongs_to_node(addr, i)) {
> > -            return i;
> > -        }
> > -    }
> > -
> > -    error_setg(errp, "Address 0x" RAM_ADDR_FMT " doesn't belong to any "
> > -                "NUMA node", addr);
> > -    return -1;
> > -}
> >  
> >  static void parse_numa_node(MachineState *ms, NumaNodeOptions *node,
> >                              Error **errp)
> > @@ -497,12 +411,6 @@ void parse_numa_opts(MachineState *ms)
> >              exit(1);
> >          }
> >  
> > -        for (i = 0; i < nb_numa_nodes; i++) {
> > -            QLIST_INIT(&numa_info[i].addr);
> > -        }
> > -
> > -        numa_set_mem_ranges();
> > -
> >          /* QEMU needs at least all unique node pair distances to build
> >           * the whole NUMA distance table. QEMU treats the distance table
> >           * as symmetric by default, i.e. distance A->B == distance B->A.
> > @@ -522,8 +430,6 @@ void parse_numa_opts(MachineState *ms)
> >              /* Validation succeeded, now fill in any missing distances. */
> >              complete_init_numa_distance();
> >          }
> > -    } else {
> > -        numa_set_mem_node_id(0, ram_size, 0);
> >      }
> >  }
> >    
>