[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-ID: <20230617180420.GA410966@sumitra.com>
Date: Sat, 17 Jun 2023 11:04:20 -0700
From: Sumitra Sharma <sumitraartsy@...il.com>
To: Jani Nikula <jani.nikula@...ux.intel.com>,
Joonas Lahtinen <joonas.lahtinen@...ux.intel.com>,
Rodrigo Vivi <rodrigo.vivi@...el.com>,
Tvrtko Ursulin <tvrtko.ursulin@...ux.intel.com>,
David Airlie <airlied@...il.com>,
Daniel Vetter <daniel@...ll.ch>,
intel-gfx@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org,
linux-kernel@...r.kernel.org
Cc: Ira Weiny <ira.weiny@...el.com>, Fabio <fmdefrancesco@...il.com>,
Deepak R Varma <drv@...lo.com>,
Sumitra Sharma <sumitraartsy@...il.com>
Subject: [PATCH v2] drm/i915: Replace kmap() with kmap_local_page()
kmap() has been deprecated in favor of the kmap_local_page()
due to high cost, restricted mapping space, the overhead of a
global lock for synchronization, and making the process sleep
in the absence of free slots.
kmap_local_page() is faster than kmap() and offers thread-local
and CPU-local mappings, take pagefaults in a local kmap region
and preserves preemption by saving the mappings of outgoing tasks
and restoring those of the incoming one during a context switch.
The mapping is kept thread local in the function
“i915_vma_coredump_create” in i915_gpu_error.c
Therefore, replace kmap() with kmap_local_page().
Suggested-by: Ira Weiny <ira.weiny@...el.com>
Signed-off-by: Sumitra Sharma <sumitraartsy@...il.com>
---
Changes in v2:
- Replace kmap() with kmap_local_page().
- Change commit subject and message.
drivers/gpu/drm/i915/i915_gpu_error.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index f020c0086fbc..bc41500eedf5 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -1164,9 +1164,9 @@ i915_vma_coredump_create(const struct intel_gt *gt,
drm_clflush_pages(&page, 1);
- s = kmap(page);
+ s = kmap_local_page(page);
ret = compress_page(compress, s, dst, false);
- kunmap(page);
+ kunmap_local(s);
drm_clflush_pages(&page, 1);
--
2.25.1
Powered by blists - more mailing lists