From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-pf0-f193.google.com ([209.85.192.193]:35119 "EHLO mail-pf0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751787AbdEATiL (ORCPT ); Mon, 1 May 2017 15:38:11 -0400 Date: Mon, 1 May 2017 12:38:07 -0700 From: Dmitry Torokhov To: Brian Norris Cc: Ganapathi Bhat , Nishant Sarmukadam , linux-kernel@vger.kernel.org, Kalle Valo , linux-wireless@vger.kernel.org Subject: Re: [PATCH v3 1/2] mwifiex: initiate card-specific work atomically Message-ID: <20170501193807.GA34444@dtor-ws> (sfid-20170501_213956_801681_9673317E) References: <20170501193700.89264-1-briannorris@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20170501193700.89264-1-briannorris@chromium.org> Sender: linux-wireless-owner@vger.kernel.org List-ID: On Mon, May 01, 2017 at 12:36:59PM -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 Reviewed-by: Dmitry Torokhov > --- > v3: fix bisectability (unused code warning) -- some code from patch 2 > crept in here > > v2: new > --- > drivers/net/wireless/marvell/mwifiex/pcie.c | 9 +++------ > drivers/net/wireless/marvell/mwifiex/sdio.c | 16 +++++----------- > 2 files changed, 8 insertions(+), 17 deletions(-) > > diff --git a/drivers/net/wireless/marvell/mwifiex/pcie.c b/drivers/net/wireless/marvell/mwifiex/pcie.c > index ac62bce50e96..5f56e8e6d612 100644 > --- a/drivers/net/wireless/marvell/mwifiex/pcie.c > +++ b/drivers/net/wireless/marvell/mwifiex/pcie.c > @@ -2837,12 +2837,9 @@ 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; > - > - 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); > } > > 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 > -- Dmitry