Hi maintainers, Just kindly ping. May I ask if this refresh version could be merged into the next tree of the i915? Thanks, Zhao On Sun, Dec 03, 2023 at 09:29:38PM +0800, Zhao Liu wrote: > Date: Sun, 3 Dec 2023 21:29:38 +0800 > From: Zhao Liu <zhao1.liu@xxxxxxxxxxxxxxx> > Subject: [PATCH v3 0/9] drm/i915: Replace kmap_atomic() with > kmap_local_page() > X-Mailer: git-send-email 2.34.1 > > From: Zhao Liu <zhao1.liu@xxxxxxxxx> > > Hi all, > > I refreshed this v3 by rebasing v2 [1] on the commit 968f35f4ab1c > ("Merge tag 'v6.7-rc3-smb3-client-fixes' of git://git.samba.org/sfrench/ > cifs-2.6"). > > Based on the current code, I rechecked the substitutions in v2 and they > still stand and are valid, so no code change in v3. > > Thanks for all the review! And sorry v2 was missed, I'll pay more > attention to this v3. > > > Purpose of This Patchset > ======================== > > The purpose of this pacthset is to replace all uses of kmap_atomic() in > i915 with kmap_local_page() because the use of kmap_atomic() is being > deprecated in favor of kmap_local_page()[2]. And 92b64bd (mm/highmem: > add notes about conversions from kmap{,_atomic}()) has declared the > deprecation of kmap_atomic(). > > > Motivation for Deprecating kmap_atomic() and Using kmap_local_page() > ==================================================================== > > The main difference between atomic and local mappings is that local > mappings doesn't disable page faults or preemption (the preemption is > disabled for !PREEMPT_RT case, otherwise it only disables migration). > > With kmap_local_page(), we can avoid the often unwanted side effect of > unnecessary page faults and preemption disables. > > > Patch summary > ============= > > Patch 1, 4-6 and 8-9 replace kmap_atomic()/kunmap_atomic() with > kmap_local_page()/kunmap_local() directly. With these local > mappings, the page faults and preemption are allowed. > > Patch 2 and 7 use memcpy_from_page() and memcpy_to_page() to replace > kmap_atomic()/kunmap_atomic(). These two variants of memcpy() > are based on the local mapping, so page faults and preemption > are also allowed in these two interfaces. > > Patch 3 replaces kmap_atomic()/kunmap_atomic() with kmap_local_page()/ > kunmap_local() and also disable page fault since the for special > handling (pls see the commit message). > > > Reference > ========= > > [1]: https://lore.kernel.org/all/20230329073220.3982460-1-zhao1.liu@xxxxxxxxxxxxxxx/ > [2]: https://lore.kernel.org/all/20220813220034.806698-1-ira.weiny@xxxxxxxxx > > > Thanks and Best Regards, > Zhao > > --- > Changlog: > > Changes since v2: > * Rebased on 968f35f4ab1c ("Merge tag 'v6.7-rc3-smb3-client-fixes' of > git://git.samba.org/sfrench/cifs-2.6"). > * Removed changelog (of v2) in commit message. > * Fixed typo in cover letter (Fabio). > * Added Reviewed-by tags from Ira and Fabio. > > Changes since v1: > * Dropped hot plug related description in commit message since it has > nothing to do with kmap_local_page(). > * Emphasized the motivation for using kmap_local_page() in commit > message. > * Rebased patch 1 on f47e630 (drm/i915/gem: Typecheck page lookups) to > keep the "idx" variable of type pgoff_t here. > * Used memcpy_from_page() and memcpy_to_page() to replace > kmap_local_page() + memcpy() in patch 2. > > --- > Zhao Liu (9): > drm/i915: Use kmap_local_page() in gem/i915_gem_object.c > drm/i915: Use memcpy_[from/to]_page() in gem/i915_gem_pyhs.c > drm/i915: Use kmap_local_page() in gem/i915_gem_shmem.c > drm/i915: Use kmap_local_page() in gem/selftests/huge_pages.c > drm/i915: Use kmap_local_page() in gem/selftests/i915_gem_coherency.c > drm/i915: Use kmap_local_page() in gem/selftests/i915_gem_context.c > drm/i915: Use memcpy_from_page() in gt/uc/intel_uc_fw.c > drm/i915: Use kmap_local_page() in i915_cmd_parser.c > drm/i915: Use kmap_local_page() in gem/i915_gem_execbuffer.c > > drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c | 10 +++++----- > drivers/gpu/drm/i915/gem/i915_gem_object.c | 8 +++----- > drivers/gpu/drm/i915/gem/i915_gem_phys.c | 10 ++-------- > drivers/gpu/drm/i915/gem/i915_gem_shmem.c | 6 ++++-- > drivers/gpu/drm/i915/gem/selftests/huge_pages.c | 6 +++--- > .../gpu/drm/i915/gem/selftests/i915_gem_coherency.c | 12 ++++-------- > .../gpu/drm/i915/gem/selftests/i915_gem_context.c | 8 ++++---- > drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c | 5 +---- > drivers/gpu/drm/i915/i915_cmd_parser.c | 4 ++-- > 9 files changed, 28 insertions(+), 41 deletions(-) > > -- > 2.34.1 >