LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Sanjay R Mehta <sanju.mehta@amd.com>
To: jdmason@kudzu.us, dave.jiang@intel.com, allenbh@gmail.com,
	arindam.nath@amd.com, logang@deltatee.com,
	Shyam-sundar.S-k@amd.com
Cc: linux-ntb@googlegroups.com, linux-kernel@vger.kernel.org,
	Sanjay R Mehta <sanju.mehta@amd.com>
Subject: [PATCH v2 2/5] ntb_perf: send command in response to EAGAIN
Date: Tue, 10 Mar 2020 15:54:51 -0500	[thread overview]
Message-ID: <1583873694-19151-3-git-send-email-sanju.mehta@amd.com> (raw)
In-Reply-To: <1583873694-19151-1-git-send-email-sanju.mehta@amd.com>

From: Arindam Nath <arindam.nath@amd.com>

perf_spad_cmd_send() and perf_msg_cmd_send() return
-EAGAIN after trying to send commands for a maximum
of MSG_TRIES re-tries. But currently there is no
handling for this error. These functions are invoked
from perf_service_work() through function pointers,
so rather than simply call these functions is not
enough. We need to make sure to invoke them again in
case of -EAGAIN. Since peer status bits were cleared
before calling these functions, we set the same status
bits before queueing the work again for later invocation.
This way we simply won't go ahead and initialize the
XLAT registers wrongfully in case sending the very first
command itself fails.

Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Signed-off-by: Sanjay R Mehta <sanju.mehta@amd.com>
---
 drivers/ntb/test/ntb_perf.c | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/ntb/test/ntb_perf.c b/drivers/ntb/test/ntb_perf.c
index 6d16628..9068e42 100644
--- a/drivers/ntb/test/ntb_perf.c
+++ b/drivers/ntb/test/ntb_perf.c
@@ -625,14 +625,24 @@ static void perf_service_work(struct work_struct *work)
 {
 	struct perf_peer *peer = to_peer_service(work);
 
-	if (test_and_clear_bit(PERF_CMD_SSIZE, &peer->sts))
-		perf_cmd_send(peer, PERF_CMD_SSIZE, peer->outbuf_size);
+	if (test_and_clear_bit(PERF_CMD_SSIZE, &peer->sts)) {
+		if (perf_cmd_send(peer, PERF_CMD_SSIZE, peer->outbuf_size)
+		    == -EAGAIN) {
+			set_bit(PERF_CMD_SSIZE, &peer->sts);
+			(void)queue_work(system_highpri_wq, &peer->service);
+		}
+	}
 
 	if (test_and_clear_bit(PERF_CMD_RSIZE, &peer->sts))
 		perf_setup_inbuf(peer);
 
-	if (test_and_clear_bit(PERF_CMD_SXLAT, &peer->sts))
-		perf_cmd_send(peer, PERF_CMD_SXLAT, peer->inbuf_xlat);
+	if (test_and_clear_bit(PERF_CMD_SXLAT, &peer->sts)) {
+		if (perf_cmd_send(peer, PERF_CMD_SXLAT, peer->inbuf_xlat)
+		    == -EAGAIN) {
+			set_bit(PERF_CMD_SXLAT, &peer->sts);
+			(void)queue_work(system_highpri_wq, &peer->service);
+		}
+	}
 
 	if (test_and_clear_bit(PERF_CMD_RXLAT, &peer->sts))
 		perf_setup_outbuf(peer);
-- 
2.7.4


  parent reply	other threads:[~2020-03-10 20:55 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-10 20:54 [PATCH v2 0/5] ntb perf, ntb tool and ntb-hw improvements Sanjay R Mehta
2020-03-10 20:54 ` [PATCH v2 1/5] ntb_perf: refactor code for CPU and DMA transfers Sanjay R Mehta
2020-03-10 21:21   ` Logan Gunthorpe
2020-03-11 17:44     ` Nath, Arindam
2020-03-10 20:54 ` Sanjay R Mehta [this message]
2020-03-10 21:31   ` [PATCH v2 2/5] ntb_perf: send command in response to EAGAIN Logan Gunthorpe
2020-03-11 18:11     ` Nath, Arindam
2020-03-11 18:47       ` Logan Gunthorpe
2020-03-11 18:58         ` Nath, Arindam
2020-03-10 20:54 ` [PATCH v2 3/5] ntb_perf: pass correct struct device to dma_alloc_coherent Sanjay R Mehta
2020-03-10 20:54 ` [PATCH v2 4/5] ntb_tool: " Sanjay R Mehta
2020-03-10 20:54 ` [PATCH v2 5/5] ntb: hw: remove the code that sets the DMA mask Sanjay R Mehta

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1583873694-19151-3-git-send-email-sanju.mehta@amd.com \
    --to=sanju.mehta@amd.com \
    --cc=Shyam-sundar.S-k@amd.com \
    --cc=allenbh@gmail.com \
    --cc=arindam.nath@amd.com \
    --cc=dave.jiang@intel.com \
    --cc=jdmason@kudzu.us \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-ntb@googlegroups.com \
    --cc=logang@deltatee.com \
    --subject='Re: [PATCH v2 2/5] ntb_perf: send command in response to EAGAIN' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).