From: Mike Rapoport <rppt@xxxxxxxxxxxxx> 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/20200818151634.14343-3-rppt@xxxxxxxxxx Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Reviewed-by: Baoquan He <bhe@xxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Daniel Axtens <dja@xxxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: Emil Renner Berthing <kernel@xxxxxxxx> Cc: Hari Bathini <hbathini@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> Cc: Max Filippov <jcmvbkbc@xxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Michal Simek <monstr@xxxxxxxxx> Cc: Miguel Ojeda <miguel.ojeda.sandonis@xxxxxxxxx> Cc: Palmer Dabbelt <palmer@xxxxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Paul Walmsley <paul.walmsley@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Russell King <linux@xxxxxxxxxxxxxxx> Cc: Stafford Horne <shorne@xxxxxxxxx> Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- kernel/dma/contiguous.c | 11 +---------- 1 file changed, 1 insertion(+), 10 deletions(-) --- 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; } _
