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List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird To: Ekansh Gupta , dri-devel@lists.freedesktop.org, iommu@lists.linux.dev, linux-media@vger.kernel.org, linux-arm-msm@vger.kernel.org, linaro-mm-sig@lists.linaro.org, =?UTF-8?Q?Christian_K=C3=B6nig?= , David Airlie , =?UTF-8?B?SsO2cmcgUsO2ZGVs?= , Jonathan Corbet , Maarten Lankhorst , Maxime Ripard , Oded Gabbay , Robin Murphy , Shuah Khan , Simona Vetter , Sumit Semwal , Thomas Zimmermann Cc: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Bharath Kumar , Bjorn Andersson , Chenna Kesava Raju , Dmitry Baryshkov , Konrad Dybcio , Rob Clark , Srinivas Kandagatla , Will Deacon References: <20260519-qda-series-v1-9-b2d984c297f8@oss.qualcomm.com> Subject: Re: [PATCH 09/15] accel/qda: Add DMA-backed GEM objects and memory manager integration Content-Language: en-GB, de-DE From: Markus Elfring In-Reply-To: <20260519-qda-series-v1-9-b2d984c297f8@oss.qualcomm.com> Content-Type: text/plain; charset=UTF-8 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1ahWs/y6JhlcAinqQEM8vz5QXAE85L/bSRVoPYM/Y52fa7CAOmEJVrZ+o6dfLbmsDYBf3CDBA V2Cvpfffj3SsF7bv1vtacGXDIRipvW6KQVWAweXzqiHpgxin24Qh71c/CnJ2VmPXS8IChn/Xh MfOVMZMlFJ47nKOus3JTVLDdU+cpikIhQ1xJyLBiBQYgJemqcszpMvJZhNAncViafeIIZFjAk c0hRcyEqsrEIvIItTn23guEE3gpkb/L/YeMvOGDBfAGdRnPq+C1kuNGMlOSBrMz32YY+e0hYW 2xwz4YiawcJRtkMOEW2Yp9mwtGo= =E2=80=A6 > Assisted-by: Claude:claude-4-6-sonnet =E2=80=A6 Did such an information source gather the knowledge to benefit more from the application of scope-based resource management? =E2=80=A6 > +++ b/drivers/accel/qda/qda_drv.c =E2=80=A6 > @@ -32,6 +33,18 @@ static void qda_postclose(struct drm_device *dev, str= uct drm_file *file) > { =E2=80=A6 > + if (refcount_dec_and_test(&iommu_dev->refcount)) { > + spin_lock_irqsave(&iommu_dev->lock, flags); > + iommu_dev->assigned_pid =3D 0; > + iommu_dev->assigned_file_priv =3D NULL; > + spin_unlock_irqrestore(&iommu_dev->lock, flags); > + } =E2=80=A6 Under which circumstances would you become interested to apply a statement like =E2=80=9Cguard(spinlock_irqsave)(&iommu_dev->lock);=E2=80=9D? https://elixir.bootlin.com/linux/v7.1-rc4/source/include/linux/spinlock.h#= L619-L622 Regards, Markus