[163/181] dma-contiguous: simplify cma_early_percent_memory()

Commit Message

Andrew Morton Oct. 13, 2020, 11:57 p.m. UTC

From: Mike Rapoport <[e-mail]>
Subject: dma-contiguous: simplify cma_early_percent_memory()

The memory size calculation in cma_early_percent_memory() traverses
memblock.memory rather than simply call memblock_phys_mem_size().  The
comment in that function suggests that at some point there should have
been call to memblock_analyze() before memblock_phys_mem_size() could be
used.  As of now, there is no memblock_analyze() at all and
memblock_phys_mem_size() can be used as soon as cold-plug memory is
registered with memblock.

Replace loop over memblock.memory with a call to memblock_phys_mem_size().

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Mike Rapoport <[e-mail]>
Reviewed-by: Christoph Hellwig <[e-mail]>
Reviewed-by: Baoquan He <[e-mail]>
Cc: Andy Lutomirski <[e-mail]>
Cc: Benjamin Herrenschmidt <[e-mail]>
Cc: Borislav Petkov <[e-mail]>
Cc: Catalin Marinas <[e-mail]>
Cc: Daniel Axtens <[e-mail]>
Cc: Dave Hansen <[e-mail]>
Cc: Emil Renner Berthing <[e-mail]>
Cc: Hari Bathini <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: Jonathan Cameron <[e-mail]>
Cc: Marek Szyprowski <[e-mail]>
Cc: Max Filippov <[e-mail]>
Cc: Michael Ellerman <[e-mail]>
Cc: Michal Simek <[e-mail]>
Cc: Miguel Ojeda <[e-mail]>
Cc: Palmer Dabbelt <[e-mail]>
Cc: Paul Mackerras <[e-mail]>
Cc: Paul Walmsley <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Russell King <[e-mail]>
Cc: Stafford Horne <[e-mail]>
Cc: Thomas Bogendoerfer <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Cc: Will Deacon <[e-mail]>
Cc: Yoshinori Sato <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
---

 kernel/dma/contiguous.c |   11 +----------
 1 file changed, 1 insertion(+), 10 deletions(-)

Patch

--- a/kernel/dma/contiguous.c~dma-contiguous-simplify-cma_early_percent_memory
+++ a/kernel/dma/contiguous.c
@@ -73,16 +73,7 @@  early_param("cma", early_cma);
 
 static phys_addr_t __init __maybe_unused cma_early_percent_memory(void)
 {
-	struct memblock_region *reg;
-	unsigned long total_pages = 0;
-
-	/*
-	 * We cannot use memblock_phys_mem_size() here, because
-	 * memblock_analyze() has not been called yet.
-	 */
-	for_each_memblock(memory, reg)
-		total_pages += memblock_region_memory_end_pfn(reg) -
-			       memblock_region_memory_base_pfn(reg);
+	unsigned long total_pages = PHYS_PFN(memblock_phys_mem_size());
 
 	return (total_pages * CONFIG_CMA_SIZE_PERCENTAGE / 100) << PAGE_SHIFT;
 }