From 7d0445d66a7619e23257570daa794dbf1d89c2a6 Mon Sep 17 00:00:00 2001 From: Michal Schmidt Date: Tue, 25 Feb 2014 16:04:24 +0100 Subject: [PATCH 1/3] bnx2x: clamp num_queues to prevent passing a negative value Use the clamp() macro to make the calculation of the number of queues slightly easier to understand. It also avoids a crash when someone accidentally passes a negative value in num_queues= module parameter. Signed-off-by: Michal Schmidt Signed-off-by: David S. Miller --- drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c index 89d75c24335c..34d124998823 100644 --- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c +++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c @@ -61,10 +61,9 @@ static void bnx2x_add_all_napi(struct bnx2x *bp) static int bnx2x_calc_num_queues(struct bnx2x *bp) { - return bnx2x_num_queues ? - min_t(int, bnx2x_num_queues, BNX2X_MAX_QUEUES(bp)) : - min_t(int, netif_get_num_default_rss_queues(), - BNX2X_MAX_QUEUES(bp)); + int nq = bnx2x_num_queues ? : netif_get_num_default_rss_queues(); + nq = clamp(nq, 1, BNX2X_MAX_QUEUES(bp)); + return nq; } /** From ff2ad3071f56697920a7154ca301fd45d17d57d2 Mon Sep 17 00:00:00 2001 From: Michal Schmidt Date: Tue, 25 Feb 2014 16:04:25 +0100 Subject: [PATCH 2/3] bnx2x: save RAM in kdump kernel by using a single queue When running in a kdump kernel, make sure to use only a single ethernet queue even if a num_queues option in /etc/modprobe.d/*.conf would specify otherwise. This saves memory, which tends to be scarce in kdump. This saves about 40 MB in the kdump environment on a setup with num_queues=8 in the config file. Signed-off-by: Michal Schmidt Signed-off-by: David S. Miller --- drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c index 34d124998823..26bc25bd465d 100644 --- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c +++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c @@ -62,6 +62,11 @@ static void bnx2x_add_all_napi(struct bnx2x *bp) static int bnx2x_calc_num_queues(struct bnx2x *bp) { int nq = bnx2x_num_queues ? : netif_get_num_default_rss_queues(); + + /* Reduce memory usage in kdump environment by using only one queue */ + if (reset_devices) + nq = 1; + nq = clamp(nq, 1, BNX2X_MAX_QUEUES(bp)); return nq; } From 94d9de3cf7b7902253e65d7aef30f2db051c1ac6 Mon Sep 17 00:00:00 2001 From: Michal Schmidt Date: Tue, 25 Feb 2014 16:04:26 +0100 Subject: [PATCH 3/3] bnx2x: save RAM in kdump kernel by disabling TPA When running in a kdump kernel, disable TPA. This saves memory, which tends to be scarce in kdump. TPA, being a receive acceleration, is unlikely to be useful for kdump, whose purpose is to send the memory image out. This saves additional 5 MB in the kdump environment. Signed-off-by: Michal Schmidt Signed-off-by: David S. Miller --- drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c index 230dea623895..5e74599b05c7 100644 --- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c +++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c @@ -11804,6 +11804,8 @@ static int bnx2x_init_bp(struct bnx2x *bp) bp->disable_tpa = disable_tpa; bp->disable_tpa |= IS_MF_STORAGE_SD(bp) || IS_MF_FCOE_AFEX(bp); + /* Reduce memory usage in kdump environment by disabling TPA */ + bp->disable_tpa |= reset_devices; /* Set TPA flags */ if (bp->disable_tpa) {