Re: libxc: domain restore: fold redundant variables

[Andrew Cooper <andrew.cooper3@citrix.com>]

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On 24/03/14 12:14, Jan Beulich wrote:
> "vcpuextstate_size" being non-zero fully expresses "vcpuextstate" being
> true - drop the latter.
>
> Signed-off-by: Jan Beulich <jbeulich@suse.com>

Having just reverse engineered this as part of rewriting migration from
scratch, this looks accurate.

Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

>
> --- a/tools/libxc/xc_domain_restore.c
> +++ b/tools/libxc/xc_domain_restore.c
> @@ -248,7 +248,7 @@ static int uncanonicalize_pagetable(
>  static xen_pfn_t *load_p2m_frame_list(
>      xc_interface *xch, struct restore_ctx *ctx,
>      int io_fd, int *pae_extended_cr3, int *ext_vcpucontext,
> -    int *vcpuextstate, uint32_t *vcpuextstate_size)
> +    uint32_t *vcpuextstate_size)
>  {
>      xen_pfn_t *p2m_frame_list;
>      vcpu_guest_context_any_t ctxt;
> @@ -326,7 +326,6 @@ static xen_pfn_t *load_p2m_frame_list(
>              }
>              else if ( !strncmp(chunk_sig, "xcnt", 4) )
>              {
> -                *vcpuextstate = 1;
>                  if ( RDEXACT(io_fd, vcpuextstate_size, sizeof(*vcpuextstate_size)) )
>                  {
>                      PERROR("read extended vcpu state size failed");
> @@ -520,7 +519,7 @@ static int buffer_tail_hvm(xc_interface 
>                             struct tailbuf_hvm *buf, int fd,
>                             unsigned int max_vcpu_id, uint64_t *vcpumap,
>                             int ext_vcpucontext,
> -                           int vcpuextstate, uint32_t vcpuextstate_size)
> +                           uint32_t vcpuextstate_size)
>  {
>      uint8_t *tmp;
>      unsigned char qemusig[21];
> @@ -588,7 +587,6 @@ static int buffer_tail_pv(xc_interface *
>                            struct tailbuf_pv *buf, int fd,
>                            unsigned int max_vcpu_id, uint64_t *vcpumap,
>                            int ext_vcpucontext,
> -                          int vcpuextstate,
>                            uint32_t vcpuextstate_size)
>  {
>      unsigned int i;
> @@ -629,9 +627,7 @@ static int buffer_tail_pv(xc_interface *
>                 : sizeof(vcpu_guest_context_x86_32_t)) * buf->vcpucount;
>      if ( ext_vcpucontext )
>          vcpulen += 128 * buf->vcpucount;
> -    if ( vcpuextstate ) {
> -        vcpulen += vcpuextstate_size * buf->vcpucount;
> -    }
> +    vcpulen += vcpuextstate_size * buf->vcpucount;
>  
>      if ( !(buf->vcpubuf) ) {
>          if ( !(buf->vcpubuf = malloc(vcpulen)) ) {
> @@ -671,16 +667,14 @@ static int buffer_tail_pv(xc_interface *
>  static int buffer_tail(xc_interface *xch, struct restore_ctx *ctx,
>                         tailbuf_t *buf, int fd, unsigned int max_vcpu_id,
>                         uint64_t *vcpumap, int ext_vcpucontext,
> -                       int vcpuextstate, uint32_t vcpuextstate_size)
> +                       uint32_t vcpuextstate_size)
>  {
>      if ( buf->ishvm )
>          return buffer_tail_hvm(xch, ctx, &buf->u.hvm, fd, max_vcpu_id, vcpumap,
> -                               ext_vcpucontext, vcpuextstate,
> -                               vcpuextstate_size);
> +                               ext_vcpucontext, vcpuextstate_size);
>      else
>          return buffer_tail_pv(xch, ctx, &buf->u.pv, fd, max_vcpu_id, vcpumap,
> -                              ext_vcpucontext, vcpuextstate,
> -                              vcpuextstate_size);
> +                              ext_vcpucontext, vcpuextstate_size);
>  }
>  
>  static void tailbuf_free_hvm(struct tailbuf_hvm *buf)
> @@ -1421,7 +1415,6 @@ int xc_domain_restore(xc_interface *xch,
>      DECLARE_DOMCTL;
>      xc_dominfo_t info;
>      int rc = 1, frc, i, j, n, m, pae_extended_cr3 = 0, ext_vcpucontext = 0;
> -    int vcpuextstate = 0;
>      uint32_t vcpuextstate_size = 0;
>      unsigned long mfn, pfn;
>      int nraces = 0;
> @@ -1527,7 +1520,7 @@ int xc_domain_restore(xc_interface *xch,
>          /* Load the p2m frame list, plus potential extended info chunk */
>          p2m_frame_list = load_p2m_frame_list(xch, ctx,
>              io_fd, &pae_extended_cr3, &ext_vcpucontext,
> -            &vcpuextstate, &vcpuextstate_size);
> +            &vcpuextstate_size);
>  
>          if ( !p2m_frame_list )
>              goto out;
> @@ -1730,7 +1723,7 @@ int xc_domain_restore(xc_interface *xch,
>      if ( !ctx->completed ) {
>  
>          if ( buffer_tail(xch, ctx, &tailbuf, io_fd, max_vcpu_id, vcpumap,
> -                         ext_vcpucontext, vcpuextstate, vcpuextstate_size) < 0 ) {
> +                         ext_vcpucontext, vcpuextstate_size) < 0 ) {
>              ERROR ("error buffering image tail");
>              goto out;
>          }
> @@ -1783,7 +1776,7 @@ int xc_domain_restore(xc_interface *xch,
>      memset(&tmptail, 0, sizeof(tmptail));
>      tmptail.ishvm = hvm;
>      if ( buffer_tail(xch, ctx, &tmptail, io_fd, max_vcpu_id, vcpumap,
> -                     ext_vcpucontext, vcpuextstate, vcpuextstate_size) < 0 ) {
> +                     ext_vcpucontext, vcpuextstate_size) < 0 ) {
>          ERROR ("error buffering image tail, finishing");
>          goto out;
>      }
> @@ -2147,7 +2140,7 @@ int xc_domain_restore(xc_interface *xch,
>          }
>  
>   vcpu_ext_state_restore:
> -        if ( !vcpuextstate )
> +        if ( !vcpuextstate_size )
>              continue;
>  
>          memcpy(&domctl.u.vcpuextstate.xfeature_mask, vcpup,
>
>
>
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xen.org
> http://lists.xen.org/xen-devel


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