From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Chan Subject: [PATCH net-next v2 09/14] bnxt_en: reduce timeout on initial HWRM calls Date: Thu, 26 Apr 2018 17:44:39 -0400 Message-ID: <1524779084-4016-10-git-send-email-michael.chan@broadcom.com> References: <1524779084-4016-1-git-send-email-michael.chan@broadcom.com> Cc: netdev@vger.kernel.org, Andy Gospodarek To: davem@davemloft.net Return-path: Received: from mail-pf0-f194.google.com ([209.85.192.194]:38697 "EHLO mail-pf0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755995AbeDZVpE (ORCPT ); Thu, 26 Apr 2018 17:45:04 -0400 Received: by mail-pf0-f194.google.com with SMTP id o76so14672244pfi.5 for ; Thu, 26 Apr 2018 14:45:04 -0700 (PDT) In-Reply-To: <1524779084-4016-1-git-send-email-michael.chan@broadcom.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Andy Gospodarek Testing with DIM enabled on older kernels indicated that firmware calls were slower than expected. More detailed analysis indicated that the default 25us delay was higher than necessary. Reducing the time spend in usleep_range() for the first several calls would reduce the overall latency of firmware calls on newer Intel processors. Signed-off-by: Andy Gospodarek Signed-off-by: Michael Chan --- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 26 +++++++++++++++++++++++--- drivers/net/ethernet/broadcom/bnxt/bnxt.h | 6 ++++++ 2 files changed, 29 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c index a221a10..ff9a5cd 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c @@ -3495,15 +3495,29 @@ static int bnxt_hwrm_do_send_msg(struct bnxt *bp, void *msg, u32 msg_len, if (!timeout) timeout = DFLT_HWRM_CMD_TIMEOUT; + /* convert timeout to usec */ + timeout *= 1000; i = 0; - tmo_count = timeout * 40; + /* Short timeout for the first few iterations: + * number of loops = number of loops for short timeout + + * number of loops for standard timeout. + */ + tmo_count = HWRM_SHORT_TIMEOUT_COUNTER; + timeout = timeout - HWRM_SHORT_MIN_TIMEOUT * HWRM_SHORT_TIMEOUT_COUNTER; + tmo_count += DIV_ROUND_UP(timeout, HWRM_MIN_TIMEOUT); resp_len = bp->hwrm_cmd_resp_addr + HWRM_RESP_LEN_OFFSET; if (intr_process) { /* Wait until hwrm response cmpl interrupt is processed */ while (bp->hwrm_intr_seq_id != HWRM_SEQ_ID_INVALID && i++ < tmo_count) { - usleep_range(25, 40); + /* on first few passes, just barely sleep */ + if (i < HWRM_SHORT_TIMEOUT_COUNTER) + usleep_range(HWRM_SHORT_MIN_TIMEOUT, + HWRM_SHORT_MAX_TIMEOUT); + else + usleep_range(HWRM_MIN_TIMEOUT, + HWRM_MAX_TIMEOUT); } if (bp->hwrm_intr_seq_id != HWRM_SEQ_ID_INVALID) { @@ -3521,7 +3535,13 @@ static int bnxt_hwrm_do_send_msg(struct bnxt *bp, void *msg, u32 msg_len, HWRM_RESP_LEN_SFT; if (len) break; - usleep_range(25, 40); + /* on first few passes, just barely sleep */ + if (i < DFLT_HWRM_CMD_TIMEOUT) + usleep_range(HWRM_SHORT_MIN_TIMEOUT, + HWRM_SHORT_MAX_TIMEOUT); + else + usleep_range(HWRM_MIN_TIMEOUT, + HWRM_MAX_TIMEOUT); } if (i >= tmo_count) { diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h index 057f8a2..7fa4a45 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h @@ -532,6 +532,12 @@ struct rx_tpa_end_cmp_ext { #define BNXT_HWRM_REQ_MAX_SIZE 128 #define BNXT_HWRM_REQS_PER_PAGE (BNXT_PAGE_SIZE / \ BNXT_HWRM_REQ_MAX_SIZE) +#define HWRM_SHORT_MIN_TIMEOUT 3 +#define HWRM_SHORT_MAX_TIMEOUT 10 +#define HWRM_SHORT_TIMEOUT_COUNTER 5 + +#define HWRM_MIN_TIMEOUT 25 +#define HWRM_MAX_TIMEOUT 40 #define BNXT_RX_EVENT 1 #define BNXT_AGG_EVENT 2 -- 1.8.3.1