[PATCH v3 12/18] bnx2x: Eliminate duplicate barriers on weakly-ordered archs
From: Sinan Kaya <hidden>
Date: 2018-03-16 16:22:25
Also in:
linux-arm-msm, lkml, netdev
Subsystem:
broadcom bnx2x 10 gigabit ethernet driver, networking drivers, the rest · Maintainers:
Sudarsana Kalluru, Manish Chopra, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Code includes wmb() followed by writel(). writel() already has a barrier on some architectures like arm64. This ends up CPU observing two barriers back to back before executing the register write. Since code already has an explicit barrier call, changing writel() to writel_relaxed(). Signed-off-by: Sinan Kaya <redacted> --- drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c
index 76a4668..3b2f1bd 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c@@ -170,7 +170,7 @@ static int bnx2x_send_msg2pf(struct bnx2x *bp, u8 *done, dma_addr_t msg_mapping) wmb(); /* Trigger the PF FW */ - writeb(1, &zone_data->trigger.vf_pf_channel.addr_valid); + writeb_relaxed(1, &zone_data->trigger.vf_pf_channel.addr_valid); /* Wait for PF to complete */ while ((tout >= 0) && (!*done)) {
--
2.7.4