Re: [PATCH v4 10/17] xen: mapcache: Break out xen_map_cache_init_single()

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Tue, 30 Apr 2024, Edgar E. Iglesias wrote:
> From: "Edgar E. Iglesias" <edgar.iglesias@xxxxxxx>
> 
> Break out xen_map_cache_init_single() in preparation for
> adding multiple map caches.
> 
> Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xxxxxxx>

Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>


> ---
>  hw/xen/xen-mapcache.c | 53 ++++++++++++++++++++++++++-----------------
>  1 file changed, 32 insertions(+), 21 deletions(-)
> 
> diff --git a/hw/xen/xen-mapcache.c b/hw/xen/xen-mapcache.c
> index dd08cd296b..72a7e25e3e 100644
> --- a/hw/xen/xen-mapcache.c
> +++ b/hw/xen/xen-mapcache.c
> @@ -93,23 +93,44 @@ static inline int test_bits(int nr, int size, const 
> unsigned long *addr)
>          return 0;
>  }
>  
> -void xen_map_cache_init(phys_offset_to_gaddr_t f, void *opaque)
> +static MapCache *xen_map_cache_init_single(phys_offset_to_gaddr_t f,
> +                                           void *opaque,
> +                                           unsigned long max_size)
>  {
>      unsigned long size;
> -    struct rlimit rlimit_as;
> +    MapCache *mc;
> +
> +    mc = g_new0(MapCache, 1);
> +
> +    mc->phys_offset_to_gaddr = f;
> +    mc->opaque = opaque;
> +    qemu_mutex_init(&mc->lock);
> +
> +    QTAILQ_INIT(&mc->locked_entries);
>  
> -    mapcache = g_new0(MapCache, 1);
> +    mc->max_mcache_size = max_size;
>  
> -    mapcache->phys_offset_to_gaddr = f;
> -    mapcache->opaque = opaque;
> -    qemu_mutex_init(&mapcache->lock);
> +    mc->nr_buckets =
> +        (((mc->max_mcache_size >> XC_PAGE_SHIFT) +
> +          (1UL << (MCACHE_BUCKET_SHIFT - XC_PAGE_SHIFT)) - 1) >>
> +         (MCACHE_BUCKET_SHIFT - XC_PAGE_SHIFT));
>  
> -    QTAILQ_INIT(&mapcache->locked_entries);
> +    size = mc->nr_buckets * sizeof(MapCacheEntry);
> +    size = (size + XC_PAGE_SIZE - 1) & ~(XC_PAGE_SIZE - 1);
> +    trace_xen_map_cache_init(mc->nr_buckets, size);
> +    mc->entry = g_malloc0(size);
> +    return mc;
> +}
> +
> +void xen_map_cache_init(phys_offset_to_gaddr_t f, void *opaque)
> +{
> +    struct rlimit rlimit_as;
> +    unsigned long max_mcache_size;
>  
>      if (geteuid() == 0) {
>          rlimit_as.rlim_cur = RLIM_INFINITY;
>          rlimit_as.rlim_max = RLIM_INFINITY;
> -        mapcache->max_mcache_size = MCACHE_MAX_SIZE;
> +        max_mcache_size = MCACHE_MAX_SIZE;
>      } else {
>          getrlimit(RLIMIT_AS, &rlimit_as);
>          rlimit_as.rlim_cur = rlimit_as.rlim_max;
> @@ -119,24 +140,14 @@ void xen_map_cache_init(phys_offset_to_gaddr_t f, void 
> *opaque)
>                          " memory is not infinity");
>          }
>          if (rlimit_as.rlim_max < MCACHE_MAX_SIZE + NON_MCACHE_MEMORY_SIZE) {
> -            mapcache->max_mcache_size = rlimit_as.rlim_max -
> -                NON_MCACHE_MEMORY_SIZE;
> +            max_mcache_size = rlimit_as.rlim_max - NON_MCACHE_MEMORY_SIZE;
>          } else {
> -            mapcache->max_mcache_size = MCACHE_MAX_SIZE;
> +            max_mcache_size = MCACHE_MAX_SIZE;
>          }
>      }
>  
> +    mapcache = xen_map_cache_init_single(f, opaque, max_mcache_size);
>      setrlimit(RLIMIT_AS, &rlimit_as);
> -
> -    mapcache->nr_buckets =
> -        (((mapcache->max_mcache_size >> XC_PAGE_SHIFT) +
> -          (1UL << (MCACHE_BUCKET_SHIFT - XC_PAGE_SHIFT)) - 1) >>
> -         (MCACHE_BUCKET_SHIFT - XC_PAGE_SHIFT));
> -
> -    size = mapcache->nr_buckets * sizeof (MapCacheEntry);
> -    size = (size + XC_PAGE_SIZE - 1) & ~(XC_PAGE_SIZE - 1);
> -    trace_xen_map_cache_init(mapcache->nr_buckets, size);
> -    mapcache->entry = g_malloc0(size);
>  }
>  
>  static void xen_remap_bucket(MapCache *mc,
> -- 
> 2.40.1
>