Subject: Re: [PATCH rdma-next v2 05/17] RDMA/counter: Add set/clear per-port auto mode support

From: Jason Gunthorpe <[email-masked]>
Date: Wed, 22 May 2019 13:56:08 -0300

On Mon, Apr 29, 2019 at 11:34:41AM +0300, Leon Romanovsky wrote:
> From: Mark Zhang <[email-masked]>
> 
> Add an API to support set/clear per-port auto mode.
> 
> Signed-off-by: Mark Zhang <[email-masked]>
> Reviewed-by: Majd Dibbiny <[email-masked]>
> Signed-off-by: Leon Romanovsky <[email-masked]>
>  drivers/infiniband/core/Makefile   |  2 +-
>  drivers/infiniband/core/counters.c | 77 ++++++++++++++++++++++++++++++
>  drivers/infiniband/core/device.c   |  4 ++
>  include/rdma/ib_verbs.h            |  2 +
>  include/rdma/rdma_counter.h        | 24 ++++++++++
>  include/uapi/rdma/rdma_netlink.h   | 26 ++++++++++
>  6 files changed, 134 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/infiniband/core/counters.c
> 
> diff --git a/drivers/infiniband/core/Makefile b/drivers/infiniband/core/Makefile
> index 313f2349b518..cddf748c15c9 100644
> +++ b/drivers/infiniband/core/Makefile
> @@ -12,7 +12,7 @@ ib_core-y :=			packer.o ud_header.o verbs.o cq.o rw.o sysfs.o \
>  				device.o fmr_pool.o cache.o netlink.o \
>  				roce_gid_mgmt.o mr_pool.o addr.o sa_query.o \
>  				multicast.o mad.o smi.o agent.o mad_rmpp.o \
> -				nldev.o restrack.o
> +				nldev.o restrack.o counters.o
>  
>  ib_core-$(CONFIG_SECURITY_INFINIBAND) += security.o
>  ib_core-$(CONFIG_CGROUP_RDMA) += cgroup.o
> diff --git a/drivers/infiniband/core/counters.c b/drivers/infiniband/core/counters.c
> new file mode 100644
> index 000000000000..bda8d945a758
> +++ b/drivers/infiniband/core/counters.c
> @@ -0,0 +1,77 @@
> +// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
> +/*
> + * Copyright (c) 2019 Mellanox Technologies. All rights reserved.
> + */
> +#include <rdma/ib_verbs.h>
> +#include <rdma/rdma_counter.h>
> +
> +#include "core_priv.h"
> +#include "restrack.h"
> +
> +#define ALL_AUTO_MODE_MASKS (RDMA_COUNTER_MASK_QP_TYPE)
> +
> +static int __counter_set_mode(struct rdma_counter_mode *curr,
> +			      enum rdma_nl_counter_mode new_mode,
> +			      enum rdma_nl_counter_mask new_mask)
> +{
> +	if ((new_mode == RDMA_COUNTER_MODE_AUTO) &&
> +	    ((new_mask & (~ALL_AUTO_MODE_MASKS)) ||
> +	     (curr->mode != RDMA_COUNTER_MODE_NONE)))
> +		return -EINVAL;
> +
> +	curr->mode = new_mode;
> +	curr->mask = new_mask;
> +	return 0;
> +}
> +
> +/**
> + * rdma_counter_set_auto_mode() - Turn on/off per-port auto mode
> + *
> + * When @on is true, the @mask must be set
> + */
> +int rdma_counter_set_auto_mode(struct ib_device *dev, u8 port,
> +			       bool on, enum rdma_nl_counter_mask mask)
> +{
> +	struct rdma_port_counter *port_counter;
> +	int ret;
> +
> +	if (!rdma_is_port_valid(dev, port))
> +		return -EINVAL;
> +
> +	port_counter = &dev->port_data[port].port_counter;
> +	mutex_lock(&port_counter->lock);
> +	if (on) {
> +		ret = __counter_set_mode(&port_counter->mode,
> +					 RDMA_COUNTER_MODE_AUTO, mask);
> +	} else {
> +		if (port_counter->mode.mode != RDMA_COUNTER_MODE_AUTO) {
> +			ret = -EINVAL;
> +			goto out;
> +		}
> +		ret = __counter_set_mode(&port_counter->mode,
> +					 RDMA_COUNTER_MODE_NONE, 0);
> +	}
> +
> +out:
> +	mutex_unlock(&port_counter->lock);
> +	return ret;
> +}
> +
> +void rdma_counter_init(struct ib_device *dev)
> +{
> +	struct rdma_port_counter *port_counter;
> +	u32 port;
> +
> +	if (!dev->ops.alloc_hw_stats)
> +		return;
> +
> +	rdma_for_each_port(dev, port) {
> +		port_counter = &dev->port_data[port].port_counter;
> +		port_counter->mode.mode = RDMA_COUNTER_MODE_NONE;
> +		mutex_init(&port_counter->lock);
> +	}
> +}
> +
> +void rdma_counter_cleanup(struct ib_device *dev)
> +{
> +}

Please don't add empty functions

> @@ -1304,6 +1307,7 @@ static void __ib_unregister_device(struct ib_device *ib_dev)
>  		goto out;
>  
>  	disable_device(ib_dev);
> +	rdma_counter_cleanup(ib_dev);

This is the wrong place to call this, the patch that actually adds a
body is just doing kfree's so it is properly called
'rdma_counter_release' and it belongs in ib_device_release()

And it shouldn't test hw_stats, and it shouldn't have a 'fail' stanza
for allocation either.

Jason