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From: Jan Glauber <jglauber@cavium.com>
To: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S . Miller" <davem@davemloft.net>,
	linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org,
	Mahipal Challa <Mahipal.Challa@cavium.com>,
	Robert Richter <rrichter@cavium.com>,
	Jan Glauber <jglauber@cavium.com>
Subject: [PATCH v2 3/5] crypto: thunderx_zip: Prevent division by zero
Date: Mon,  9 Apr 2018 17:45:52 +0200	[thread overview]
Message-ID: <20180409154554.7578-4-jglauber@cavium.com> (raw)
In-Reply-To: <20180409154554.7578-1-jglauber@cavium.com>

Avoid two potential divisions by zero when calculating average
values for the zip statistics.

Signed-off-by: Jan Glauber <jglauber@cavium.com>
Reviewed-by: Robert Richter <rrichter@cavium.com>
---
 drivers/crypto/cavium/zip/zip_main.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/crypto/cavium/zip/zip_main.c b/drivers/crypto/cavium/zip/zip_main.c
index 1cd8aa488185..79b449e0f955 100644
--- a/drivers/crypto/cavium/zip/zip_main.c
+++ b/drivers/crypto/cavium/zip/zip_main.c
@@ -482,10 +482,11 @@ static int zip_show_stats(struct seq_file *s, void *unused)
 				atomic64_add(val, &st->pending_req);
 			}
 
-			avg_chunk = (atomic64_read(&st->comp_in_bytes) /
-				     atomic64_read(&st->comp_req_complete));
-			avg_cr = (atomic64_read(&st->comp_in_bytes) /
-				  atomic64_read(&st->comp_out_bytes));
+			val = atomic64_read(&st->comp_req_complete);
+			avg_chunk = (val) ? atomic64_read(&st->comp_in_bytes) / val : 0;
+
+			val = atomic64_read(&st->comp_out_bytes);
+			avg_cr = (val) ? atomic64_read(&st->comp_in_bytes) / val : 0;
 			seq_printf(s, "        ZIP Device %d Stats\n"
 				      "-----------------------------------\n"
 				      "Comp Req Submitted        : \t%lld\n"
-- 
2.16.2

  parent reply	other threads:[~2018-04-09 15:45 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-09 15:45 [PATCH v2 0/5] ThunderX ZIP driver bug fixes Jan Glauber
2018-04-09 15:45 ` [PATCH v2 1/5] crypto: thunderx_zip: Fix fallout from CONFIG_VMAP_STACK Jan Glauber
2018-04-09 15:45 ` [PATCH v2 2/5] crypto: thunderx_zip: Limit result reading attempts Jan Glauber
2018-04-09 15:45 ` Jan Glauber [this message]
2018-04-09 15:45 ` [PATCH v2 4/5] crypto: thunderx_zip: Fix statistics pending request value Jan Glauber
2018-04-09 15:45 ` [PATCH v2 5/5] crypto: thunderx_zip: Fix smp_processor_id() warnings Jan Glauber
2018-04-20 16:51 ` [PATCH v2 0/5] ThunderX ZIP driver bug fixes Herbert Xu

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