net/sfc/base: more accurately calculate number of PS credits

Maximum number of packets per 64k buffer should be rounded up
when calculating number of credits by event queue size.

Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>

diff --git a/drivers/net/sfc/base/ef10_ev.c b/drivers/net/sfc/base/ef10_ev.c
index 946efeb..2c6edf3 100644 (file)
--- a/drivers/net/sfc/base/ef10_ev.c
+++ b/drivers/net/sfc/base/ef10_ev.c
@@ -1370,7 +1370,7 @@ ef10_ev_rxlabel_init(
        eersp->eers_rx_packed_stream = packed_stream;
        if (packed_stream) {
                eersp->eers_rx_packed_stream_credits = (eep->ee_mask + 1) /
-                   (EFX_RX_PACKED_STREAM_MEM_PER_CREDIT /
+                   EFX_DIV_ROUND_UP(EFX_RX_PACKED_STREAM_MEM_PER_CREDIT,
                    EFX_RX_PACKED_STREAM_MIN_PACKET_SPACE);
                EFSYS_ASSERT3U(eersp->eers_rx_packed_stream_credits, !=, 0);
                /*

diff --git a/drivers/net/sfc/base/efx.h b/drivers/net/sfc/base/efx.h
index bf17aba..d7ce0b5 100644 (file)
--- a/drivers/net/sfc/base/efx.h
+++ b/drivers/net/sfc/base/efx.h
@@ -48,6 +48,9 @@ extern "C" {
 #define        EFX_FIELD_OFFSET(_type, _field)         \
        ((size_t) &(((_type *)0)->_field))
 
+/* The macro expands divider twice */
+#define        EFX_DIV_ROUND_UP(_n, _d)                (((_n) + (_d) - 1) / (_d))
+
 /* Return codes */
 
 typedef __success(return == 0) int efx_rc_t;