Re: [PATCH 37/50] ppc/xive2: Consolidate presentation processing in context push

[Miles Glenn <milesg@linux.ibm.com>]

Reviewed-by: Glenn Miles <milesg@linux.ibm.com>

On Mon, 2025-05-12 at 13:10 +1000, Nicholas Piggin wrote:
> OS-push operation must re-present pending interrupts. Use the
> newly created xive2_tctx_process_pending() function instead of
> duplicating the logic.
> 
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
>  hw/intc/xive2.c | 42 ++++++++++--------------------------------
>  1 file changed, 10 insertions(+), 32 deletions(-)
> 
> diff --git a/hw/intc/xive2.c b/hw/intc/xive2.c
> index aa06bfda77..0fdf6a4f20 100644
> --- a/hw/intc/xive2.c
> +++ b/hw/intc/xive2.c
> @@ -903,18 +903,14 @@ static uint8_t xive2_tctx_restore_os_ctx(Xive2Router *xrtr, XiveTCTX *tctx,
>      return cppr;
>  }
>  
> +static void xive2_tctx_process_pending(XiveTCTX *tctx, uint8_t sig_ring);
> +
>  static void xive2_tctx_need_resend(Xive2Router *xrtr, XiveTCTX *tctx,
>                                     uint8_t nvp_blk, uint32_t nvp_idx,
>                                     bool do_restore)
>  {
> -    XivePresenter *xptr = XIVE_PRESENTER(xrtr);
> -    uint8_t ipb;
> -    uint8_t backlog_level;
> -    uint8_t group_level;
> -    uint8_t first_group;
> -    uint8_t backlog_prio;
> -    uint8_t group_prio;
>      uint8_t *regs = &tctx->regs[TM_QW1_OS];
> +    uint8_t ipb;
>      Xive2Nvp nvp;
>  
>      /*
> @@ -946,30 +942,8 @@ static void xive2_tctx_need_resend(Xive2Router *xrtr, XiveTCTX *tctx,
>      }
>      /* IPB bits in the backlog are merged with the TIMA IPB bits */
>      regs[TM_IPB] |= ipb;
> -    backlog_prio = xive_ipb_to_pipr(regs[TM_IPB]);
> -    backlog_level = 0;
> -
> -    first_group = xive_get_field32(NVP2_W0_PGOFIRST, nvp.w0);
> -    if (first_group && regs[TM_LSMFB] < backlog_prio) {
> -        group_prio = xive2_presenter_backlog_scan(xptr, nvp_blk, nvp_idx,
> -                                                  first_group, &group_level);
> -        regs[TM_LSMFB] = group_prio;
> -        if (regs[TM_LGS] && group_prio < backlog_prio &&
> -            group_prio < regs[TM_CPPR]) {
> -
> -            /* VP can take a group interrupt */
> -            xive2_presenter_backlog_decr(xptr, nvp_blk, nvp_idx,
> -                                         group_prio, group_level);
> -            backlog_prio = group_prio;
> -            backlog_level = group_level;
> -        }
> -    }
>  
> -    /*
> -     * Set the PIPR/NSR based on the restored state.
> -     * It will raise the External interrupt signal if needed.
> -     */
> -    xive_tctx_pipr_set(tctx, TM_QW1_OS, backlog_prio, backlog_level);
> +    xive2_tctx_process_pending(tctx, TM_QW1_OS);
>  }
>  
>  /*
> @@ -1103,8 +1077,12 @@ static void xive2_tctx_process_pending(XiveTCTX *tctx, uint8_t sig_ring)
>  {
>      uint8_t *sig_regs = &tctx->regs[sig_ring];
>      Xive2Router *xrtr = XIVE2_ROUTER(tctx->xptr);
> -    uint8_t backlog_prio, first_group, group_level;
> -    uint8_t pipr_min, lsmfb_min, ring_min;
> +    uint8_t backlog_prio;
> +    uint8_t first_group;
> +    uint8_t group_level;
> +    uint8_t pipr_min;
> +    uint8_t lsmfb_min;
> +    uint8_t ring_min;
>      uint8_t cppr = sig_regs[TM_CPPR];
>      bool group_enabled;
>      Xive2Nvp nvp;