Commits
Alexey Brodkin committed b607eddd712
ARCv2: guard SLC DMA ops with spinlock SLC maintenance ops need to be serialized by software as there is no inherent buffering / quequing of aux commands. It can silently ignore a new aux operation if previous one is still ongoing (SLC_CTRL_BUSY) So gaurd the SLC op using a spin lock The spin lock doesn't seem to be contended even in heavy workloads such as iperf. On FPGA @ 75 MHz. [1] Before this change: ============================================================ # iperf -c 10.42.0.1 ------------------------------------------------------------ Client connecting to 10.42.0.1, TCP port 5001 TCP window size: 43.8 KByte (default) ------------------------------------------------------------ [ 3] local 10.42.0.110 port 38935 connected with 10.42.0.1 port 5001 [ ID] Interval Transfer Bandwidth [ 3] 0.0-10.0 sec 48.4 MBytes 40.6 Mbits/sec ============================================================ [2] After this change: ============================================================ # iperf -c 10.42.0.1 ------------------------------------------------------------ Client connecting to 10.42.0.1, TCP port 5001 TCP window size: 43.8 KByte (default) ------------------------------------------------------------ [ 3] local 10.42.0.243 port 60248 connected with 10.42.0.1 port 5001 [ ID] Interval Transfer Bandwidth [ 3] 0.0-10.0 sec 47.5 MBytes 39.8 Mbits/sec # iperf -c 10.42.0.1 ------------------------------------------------------------ Client connecting to 10.42.0.1, TCP port 5001 TCP window size: 43.8 KByte (default) ------------------------------------------------------------ [ 3] local 10.42.0.243 port 60249 connected with 10.42.0.1 port 5001 [ ID] Interval Transfer Bandwidth [ 3] 0.0-10.0 sec 54.9 MBytes 46.0 Mbits/sec ============================================================ Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Cc: arc-linux-dev@synopsys.com Signed-off-by: Vineet Gupta <vgupta@synopsys.com>