From: Jacob Keller jacob.e.keller@intel.com
[ Upstream commit 1eb43fc754485d772b1165118a8fb80c385f0492 ]
Currently, we use a combination of ilog2 and is_power_of_2() to calculate the next power of 2 for the qcount. This appears to be causing a warning on some combinations of GCC and the Linux kernel:
MODPOST 1 modules WARNING: "____ilog2_NaN" [ice.ko] undefined!
This appears to because because GCC realizes that qcount could be zero in some circumstances and thus attempts to link against the intentionally undefined ___ilog2_NaN function.
The order_base_2 function is intentionally defined to return 0 when passed 0 as an argument, and thus will be safe to use here.
This not only fixes the warning but makes the resulting code slightly cleaner, and is really what we should have used originally.
Also update the comment to make it more clear that we are rounding up, not just incrementing the ilog2 of qcount unconditionally.
Signed-off-by: Jacob Keller jacob.e.keller@intel.com Signed-off-by: Anirudh Venkataramanan anirudh.venkataramanan@intel.com Tested-by: Tony Brelinski tonyx.brelinski@intel.com Signed-off-by: Jeff Kirsher jeffrey.t.kirsher@intel.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- drivers/net/ethernet/intel/ice/ice_main.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-)
diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c index 46b35b78e8aa..db580d41dbf9 100644 --- a/drivers/net/ethernet/intel/ice/ice_main.c +++ b/drivers/net/ethernet/intel/ice/ice_main.c @@ -1313,11 +1313,8 @@ static void ice_vsi_setup_q_map(struct ice_vsi *vsi, struct ice_vsi_ctx *ctxt) qcount = numq_tc; }
- /* find higher power-of-2 of qcount */ - pow = ilog2(qcount); - - if (!is_power_of_2(qcount)) - pow++; + /* find the (rounded up) power-of-2 of qcount */ + pow = order_base_2(qcount);
for (i = 0; i < ICE_MAX_TRAFFIC_CLASS; i++) { if (!(vsi->tc_cfg.ena_tc & BIT(i))) {