[PATCH v2 1/2] mwifiex: initiate card-specific work atomically

[PATCH v2 1/2] mwifiex: initiate card-specific work atomically

[Brian Norris]

The non-atomic test + set is a little awkward here, and it technically
means we might double-schedule work unnecessarily. AFAICT, this is not
really a problem, since the extra "work" will be a no-op (the flag(s)
will be cleared by then), but it's still an anti-pattern.

Rewrite this to use the atomic test_and_set_bit() helper instead.

Signed-off-by: Brian Norris <briannorris@chromium.org>
---
new in v2
---
 drivers/net/wireless/marvell/mwifiex/pcie.c | 13 +++++++++----
 drivers/net/wireless/marvell/mwifiex/sdio.c | 16 +++++-----------
 2 files changed, 14 insertions(+), 15 deletions(-)

diff --git a/drivers/net/wireless/marvell/mwifiex/pcie.c b/drivers/net/wireless/marvell/mwifiex/pcie.c
index ac62bce50e96..8e7d6f41a952 100644
--- a/drivers/net/wireless/marvell/mwifiex/pcie.c
+++ b/drivers/net/wireless/marvell/mwifiex/pcie.c
@@ -2837,12 +2837,17 @@ static void mwifiex_pcie_device_dump(struct mwifiex_adapter *adapter)
 {
 	struct pcie_service_card *card = adapter->card;
 
-	if (test_bit(MWIFIEX_IFACE_WORK_DEVICE_DUMP, &card->work_flags))
-		return;
+	if (!test_and_set_bit(MWIFIEX_IFACE_WORK_DEVICE_DUMP,
+			      &card->work_flags))
+		schedule_work(&card->work);
+}
 
-	set_bit(MWIFIEX_IFACE_WORK_DEVICE_DUMP, &card->work_flags);
+static void mwifiex_pcie_card_reset(struct mwifiex_adapter *adapter)
+{
+	struct pcie_service_card *card = adapter->card;
 
-	schedule_work(&card->work);
+	if (!test_and_set_bit(MWIFIEX_IFACE_WORK_CARD_RESET, &card->work_flags))
+		schedule_work(&card->work);
 }
 
 static void mwifiex_pcie_free_buffers(struct mwifiex_adapter *adapter)
diff --git a/drivers/net/wireless/marvell/mwifiex/sdio.c b/drivers/net/wireless/marvell/mwifiex/sdio.c
index 0af1c6733c92..d38d31bb9b79 100644
--- a/drivers/net/wireless/marvell/mwifiex/sdio.c
+++ b/drivers/net/wireless/marvell/mwifiex/sdio.c
@@ -2533,12 +2533,8 @@ static void mwifiex_sdio_card_reset(struct mwifiex_adapter *adapter)
 {
 	struct sdio_mmc_card *card = adapter->card;
 
-	if (test_bit(MWIFIEX_IFACE_WORK_CARD_RESET, &card->work_flags))
-		return;
-
-	set_bit(MWIFIEX_IFACE_WORK_CARD_RESET, &card->work_flags);
-
-	schedule_work(&card->work);
+	if (!test_and_set_bit(MWIFIEX_IFACE_WORK_CARD_RESET, &card->work_flags))
+		schedule_work(&card->work);
 }
 
 /* This function dumps FW information */
@@ -2546,11 +2542,9 @@ static void mwifiex_sdio_device_dump(struct mwifiex_adapter *adapter)
 {
 	struct sdio_mmc_card *card = adapter->card;
 
-	if (test_bit(MWIFIEX_IFACE_WORK_DEVICE_DUMP, &card->work_flags))
-		return;
-
-	set_bit(MWIFIEX_IFACE_WORK_DEVICE_DUMP, &card->work_flags);
-	schedule_work(&card->work);
+	if (!test_and_set_bit(MWIFIEX_IFACE_WORK_DEVICE_DUMP,
+			      &card->work_flags))
+		schedule_work(&card->work);
 }
 
 /* Function to dump SDIO function registers and SDIO scratch registers in case
-- 
2.13.0.rc0.306.g87b477812d-goog

[PATCH v2 2/2] mwifiex: pcie: add card_reset() support

[Brian Norris]

Similar to the SDIO driver, we should implement this so that we will
automatically reset the device whenever there's a command timeout or
similar.

Signed-off-by: Brian Norris <briannorris@chromium.org>
---
v2: use atomic test/set, based on Dmitry's suggestion
---
 drivers/net/wireless/marvell/mwifiex/pcie.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/net/wireless/marvell/mwifiex/pcie.c b/drivers/net/wireless/marvell/mwifiex/pcie.c
index 8e7d6f41a952..78688ff6ecd0 100644
--- a/drivers/net/wireless/marvell/mwifiex/pcie.c
+++ b/drivers/net/wireless/marvell/mwifiex/pcie.c
@@ -2822,6 +2822,13 @@ static void mwifiex_pcie_device_dump_work(struct mwifiex_adapter *adapter)
 	mwifiex_upload_device_dump(adapter, drv_info, drv_info_size);
 }
 
+static void mwifiex_pcie_card_reset_work(struct mwifiex_adapter *adapter)
+{
+	struct pcie_service_card *card = adapter->card;
+
+	pci_reset_function(card->dev);
+}
+
 static void mwifiex_pcie_work(struct work_struct *work)
 {
 	struct pcie_service_card *card =
@@ -2830,6 +2837,9 @@ static void mwifiex_pcie_work(struct work_struct *work)
 	if (test_and_clear_bit(MWIFIEX_IFACE_WORK_DEVICE_DUMP,
 			       &card->work_flags))
 		mwifiex_pcie_device_dump_work(card->adapter);
+	if (test_and_clear_bit(MWIFIEX_IFACE_WORK_CARD_RESET,
+			       &card->work_flags))
+		mwifiex_pcie_card_reset_work(card->adapter);
 }
 
 /* This function dumps FW information */
@@ -3279,6 +3289,7 @@ static struct mwifiex_if_ops pcie_ops = {
 	.cleanup_mpa_buf =		NULL,
 	.init_fw_port =			mwifiex_pcie_init_fw_port,
 	.clean_pcie_ring =		mwifiex_clean_pcie_ring_buf,
+	.card_reset =			mwifiex_pcie_card_reset,
 	.reg_dump =			mwifiex_pcie_reg_dump,
 	.device_dump =			mwifiex_pcie_device_dump,
 	.down_dev =			mwifiex_pcie_down_dev,
-- 
2.13.0.rc0.306.g87b477812d-goog

Re: [PATCH v2 1/2] mwifiex: initiate card-specific work atomically

[Brian Norris]

On Mon, May 01, 2017 at 11:45:48AM -0700, Brian Norris wrote:
> The non-atomic test + set is a little awkward here, and it technically
> means we might double-schedule work unnecessarily. AFAICT, this is not
> really a problem, since the extra "work" will be a no-op (the flag(s)
> will be cleared by then), but it's still an anti-pattern.
> 
> Rewrite this to use the atomic test_and_set_bit() helper instead.
> 
> Signed-off-by: Brian Norris <briannorris@chromium.org>
> ---
> new in v2
> ---
>  drivers/net/wireless/marvell/mwifiex/pcie.c | 13 +++++++++----
>  drivers/net/wireless/marvell/mwifiex/sdio.c | 16 +++++-----------
>  2 files changed, 14 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/net/wireless/marvell/mwifiex/pcie.c b/drivers/net/wireless/marvell/mwifiex/pcie.c
> index ac62bce50e96..8e7d6f41a952 100644
> --- a/drivers/net/wireless/marvell/mwifiex/pcie.c
> +++ b/drivers/net/wireless/marvell/mwifiex/pcie.c
> @@ -2837,12 +2837,17 @@ static void mwifiex_pcie_device_dump(struct mwifiex_adapter *adapter)
>  {
>  	struct pcie_service_card *card = adapter->card;
>  
> -	if (test_bit(MWIFIEX_IFACE_WORK_DEVICE_DUMP, &card->work_flags))
> -		return;
> +	if (!test_and_set_bit(MWIFIEX_IFACE_WORK_DEVICE_DUMP,
> +			      &card->work_flags))
> +		schedule_work(&card->work);
> +}
>  
> -	set_bit(MWIFIEX_IFACE_WORK_DEVICE_DUMP, &card->work_flags);
> +static void mwifiex_pcie_card_reset(struct mwifiex_adapter *adapter)
> +{
> +	struct pcie_service_card *card = adapter->card;
>  
> -	schedule_work(&card->work);
> +	if (!test_and_set_bit(MWIFIEX_IFACE_WORK_CARD_RESET, &card->work_flags))
> +		schedule_work(&card->work);
>  }
>  
>  static void mwifiex_pcie_free_buffers(struct mwifiex_adapter *adapter)

Ooops, mis-split on patch 1 vs. 2. This won't be bisectable! Sorry,
please ignore! Will send v3 soon.