2012/2/23 Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>: > Hi, > > This is (yet another) quick update of CMA patches. I've rebased them > onto next-20120222 tree from > git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git and > fixed the bug pointed by Aaro Koskinen. For the whole series: Tested-by: Barry Song <Baohua.Song@xxxxxxx> and i also write a simple kernel helper to test the CMA: /* * kernek module helper for testing CMA * * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company. * * Licensed under GPLv2 or later. */ #include <linux/module.h> #include <linux/device.h> #include <linux/fs.h> #include <linux/miscdevice.h> #include <linux/dma-mapping.h> #define CMA_NUM 10 static struct device *cma_dev; static dma_addr_t dma_phys[CMA_NUM]; static void *dma_virt[CMA_NUM]; /* any read request will free coherent memory, eg. * cat /dev/cma_test */ static ssize_t cma_test_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) { int i; for (i = 0; i < CMA_NUM; i++) { if (dma_virt[i]) { dma_free_coherent(cma_dev, (i + 1) * SZ_1M, dma_virt[i], dma_phys[i]); _dev_info(cma_dev, "free virt: %p phys: %p\n", dma_virt[i], (void *)dma_phys[i]); dma_virt[i] = NULL; break; } } return 0; } /* * any write request will alloc coherent memory, eg. * echo 0 > /dev/cma_test */ static ssize_t cma_test_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { int i; int ret; for (i = 0; i < CMA_NUM; i++) { if (!dma_virt[i]) { dma_virt[i] = dma_alloc_coherent(cma_dev, (i + 1) * SZ_1M, &dma_phys[i], GFP_KERNEL); if (dma_virt[i]) _dev_info(cma_dev, "alloc virt: %p phys: %p\n", dma_virt[i], (void *)dma_phys[i]); else { dev_err(cma_dev, "no mem in CMA area\n"); ret = -ENOMEM; } break; } } return count; } static const struct file_operations cma_test_fops = { .owner = THIS_MODULE, .read = cma_test_read, .write = cma_test_write, }; static struct miscdevice cma_test_misc = { .name = "cma_test", .fops = &cma_test_fops, }; static int __init cma_test_init(void) { int ret = 0; ret = misc_register(&cma_test_misc); if (unlikely(ret)) { pr_err("failed to register cma test misc device!\n"); return ret; } cma_dev = cma_test_misc.this_device; cma_dev->coherent_dma_mask = ~0; _dev_info(cma_dev, "registered.\n"); return ret; } module_init(cma_test_init); static void __exit cma_test_exit(void) { misc_deregister(&cma_test_misc); } module_exit(cma_test_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Barry Song <Baohua.Song@xxxxxxx>"); MODULE_DESCRIPTION("kernel module to help the test of CMA"); MODULE_ALIAS("CMA test"); While fulfilling "dd if=/dev/mmcblk0 of=/dev/null bs=4096 count=1024000000 &" and "dd if=/dev/zero of=/data/1 bs=4096 count=1024000000 &" to exhaust memory at background, i alloc the contiguous memories using the cma_test driver: $echo 0 > /dev/cma_test [ 16.582216] misc cma_test: alloc virt: ceb00000 phys: 0eb00000 $echo 0 > /dev/cma_test [ 20.843395] misc cma_test: alloc virt: cec00000 phys: 0ec00000 $echo 0 > /dev/cma_test [ 21.774601] misc cma_test: alloc virt: cee00000 phys: 0ee00000 $echo 0 > /dev/cma_test [ 22.925633] misc cma_test: alloc virt: cf100000 phys: 0f100000 i did see the page write back is executed and contiguous memories are always available. P.S. the whole series was also back ported to 2.6.38.8 which our release is based on. > > Best regards > Marek Szyprowski > Samsung Poland R&D Center > > Links to previous versions of the patchset: > v22: <http://www.spinics.net/lists/linux-media/msg44370.html> > v21: <http://www.spinics.net/lists/linux-media/msg44155.html> > v20: <http://www.spinics.net/lists/linux-mm/msg29145.html> > v19: <http://www.spinics.net/lists/linux-mm/msg29145.html> > v18: <http://www.spinics.net/lists/linux-mm/msg28125.html> > v17: <http://www.spinics.net/lists/arm-kernel/msg148499.html> > v16: <http://www.spinics.net/lists/linux-mm/msg25066.html> > v15: <http://www.spinics.net/lists/linux-mm/msg23365.html> > v14: <http://www.spinics.net/lists/linux-media/msg36536.html> > v13: (internal, intentionally not released) > v12: <http://www.spinics.net/lists/linux-media/msg35674.html> > v11: <http://www.spinics.net/lists/linux-mm/msg21868.html> > v10: <http://www.spinics.net/lists/linux-mm/msg20761.html> > v9: <http://article.gmane.org/gmane.linux.kernel.mm/60787> > v8: <http://article.gmane.org/gmane.linux.kernel.mm/56855> > v7: <http://article.gmane.org/gmane.linux.kernel.mm/55626> > v6: <http://article.gmane.org/gmane.linux.kernel.mm/55626> > v5: (intentionally left out as CMA v5 was identical to CMA v4) > v4: <http://article.gmane.org/gmane.linux.kernel.mm/52010> > v3: <http://article.gmane.org/gmane.linux.kernel.mm/51573> > v2: <http://article.gmane.org/gmane.linux.kernel.mm/50986> > v1: <http://article.gmane.org/gmane.linux.kernel.mm/50669> > > > Changelog: > > v23: > 1. fixed bug spotted by Aaro Koskinen (incorrect check inside VM_BUG_ON) > > 2. rebased onto next-20120222 tree from > git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git > > v22: > 1. Fixed compilation break caused by missing fixup patch in v21 > > 2. Fixed typos in the comments > > 3. Removed superfluous #include entries > > v21: > 1. Fixed incorrect check which broke memory compaction code > > 2. Fixed hacky and racy min_free_kbytes handling > > 3. Added serialization patch to watermark calculation > > 4. Fixed typos here and there in the comments > > v20 and earlier - see previous patchsets. > > > Patches in this patchset: > > Marek Szyprowski (6): > mm: extract reclaim code from __alloc_pages_direct_reclaim() > mm: trigger page reclaim in alloc_contig_range() to stabilise > watermarks > drivers: add Contiguous Memory Allocator > X86: integrate CMA with DMA-mapping subsystem > ARM: integrate CMA with DMA-mapping subsystem > ARM: Samsung: use CMA for 2 memory banks for s5p-mfc device > > Mel Gorman (1): > mm: Serialize access to min_free_kbytes > > Michal Nazarewicz (9): > mm: page_alloc: remove trailing whitespace > mm: compaction: introduce isolate_migratepages_range() > mm: compaction: introduce map_pages() > mm: compaction: introduce isolate_freepages_range() > mm: compaction: export some of the functions > mm: page_alloc: introduce alloc_contig_range() > mm: page_alloc: change fallbacks array handling > mm: mmzone: MIGRATE_CMA migration type added > mm: page_isolation: MIGRATE_CMA isolation functions added > > Documentation/kernel-parameters.txt | 9 + > arch/Kconfig | 3 + > arch/arm/Kconfig | 2 + > arch/arm/include/asm/dma-contiguous.h | 15 ++ > arch/arm/include/asm/mach/map.h | 1 + > arch/arm/kernel/setup.c | 9 +- > arch/arm/mm/dma-mapping.c | 369 ++++++++++++++++++++++++------ > arch/arm/mm/init.c | 23 ++- > arch/arm/mm/mm.h | 3 + > arch/arm/mm/mmu.c | 31 ++- > arch/arm/plat-s5p/dev-mfc.c | 51 +---- > arch/x86/Kconfig | 1 + > arch/x86/include/asm/dma-contiguous.h | 13 + > arch/x86/include/asm/dma-mapping.h | 4 + > arch/x86/kernel/pci-dma.c | 18 ++- > arch/x86/kernel/pci-nommu.c | 8 +- > arch/x86/kernel/setup.c | 2 + > drivers/base/Kconfig | 89 +++++++ > drivers/base/Makefile | 1 + > drivers/base/dma-contiguous.c | 401 +++++++++++++++++++++++++++++++ > include/asm-generic/dma-contiguous.h | 28 +++ > include/linux/device.h | 4 + > include/linux/dma-contiguous.h | 110 +++++++++ > include/linux/gfp.h | 12 + > include/linux/mmzone.h | 47 +++- > include/linux/page-isolation.h | 18 +- > mm/Kconfig | 2 +- > mm/Makefile | 3 +- > mm/compaction.c | 418 +++++++++++++++++++++------------ > mm/internal.h | 33 +++ > mm/memory-failure.c | 2 +- > mm/memory_hotplug.c | 6 +- > mm/page_alloc.c | 409 ++++++++++++++++++++++++++++---- > mm/page_isolation.c | 15 +- > mm/vmstat.c | 3 + > 35 files changed, 1790 insertions(+), 373 deletions(-) > create mode 100644 arch/arm/include/asm/dma-contiguous.h > create mode 100644 arch/x86/include/asm/dma-contiguous.h > create mode 100644 drivers/base/dma-contiguous.c > create mode 100644 include/asm-generic/dma-contiguous.h > create mode 100644 include/linux/dma-contiguous.h > > -- > 1.7.1.569.g6f426 Thanks barry -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html