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05 April 2024, 19:05:47 UTC
Revision f525ed19437d376736bed64ee7bc4afee82f2ba9 authored by Nathan Chancellor on 16 September 2022, 21:06:58 UTC, committed by Alex Deucher on 21 September 2022, 21:36:57 UTC 
drm/amd/display: Reduce number of arguments of dml314's CalculateFlipSchedule()
 
Most of the arguments are identical between the two call sites and they
can be accessed through the 'struct vba_vars_st' pointer. This reduces
the total amount of stack space that
dml314_ModeSupportAndSystemConfigurationFull() uses by 112 bytes with
LLVM 16 (1976 -> 1864), helping clear up the following clang warning:

  drivers/gpu/drm/amd/amdgpu/../display/dc/dml/dcn314/display_mode_vba_314.c:4020:6: error: stack frame size (2216) exceeds limit (2048) in 'dml314_ModeSupportAndSystemConfigurationFull' [-Werror,-Wframe-larger-than]
  void dml314_ModeSupportAndSystemConfigurationFull(struct display_mode_lib *mode_lib)
       ^
  1 error generated.

Link: https://github.com/ClangBuiltLinux/linux/issues/1710
Reported-by: "kernelci.org bot" <bot@kernelci.org>
Tested-by: Maíra Canal <mairacanal@riseup.net>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
1 parent faed5d0
Raw File
Tip revision: f525ed19437d376736bed64ee7bc4afee82f2ba9 authored by Nathan Chancellor on 16 September 2022, 21:06:58 UTC
drm/amd/display: Reduce number of arguments of dml314's CalculateFlipSchedule()
Tip revision: f525ed1
io-mapping.c 
// SPDX-License-Identifier: GPL-2.0-only

#include <linux/mm.h>
#include <linux/io-mapping.h>

/**
 * io_mapping_map_user - remap an I/O mapping to userspace
 * @iomap: the source io_mapping
 * @vma: user vma to map to
 * @addr: target user address to start at
 * @pfn: physical address of kernel memory
 * @size: size of map area
 *
 *  Note: this is only safe if the mm semaphore is held when called.
 */
int io_mapping_map_user(struct io_mapping *iomap, struct vm_area_struct *vma,
		unsigned long addr, unsigned long pfn, unsigned long size)
{
	vm_flags_t expected_flags = VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;

	if (WARN_ON_ONCE((vma->vm_flags & expected_flags) != expected_flags))
		return -EINVAL;

	/* We rely on prevalidation of the io-mapping to skip track_pfn(). */
	return remap_pfn_range_notrack(vma, addr, pfn, size,
		__pgprot((pgprot_val(iomap->prot) & _PAGE_CACHE_MASK) |
			 (pgprot_val(vma->vm_page_prot) & ~_PAGE_CACHE_MASK)));
}
EXPORT_SYMBOL_GPL(io_mapping_map_user);
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