Dear Wilk > -----Original Message----- > From: Konrad Rzeszutek Wilk [mailto:konrad.wilk@xxxxxxxxxx] > Sent: Tuesday, February 17, 2015 6:13 AM > To: Wang, Xiaoming > Cc: ralf@xxxxxxxxxxxxxx; boris.ostrovsky@xxxxxxxxxx; > david.vrabel@xxxxxxxxxx; linux-mips@xxxxxxxxxxxxxx; linux- > kernel@xxxxxxxxxxxxxxx; xen-devel@xxxxxxxxxxxxxxxxxxxx; akpm@linux- > foundation.org; linux@xxxxxxxxxxx; lauraa@xxxxxxxxxxxxxx; > heiko.carstens@xxxxxxxxxx; d.kasatkin@xxxxxxxxxxx; > takahiro.akashi@xxxxxxxxxx; chris@xxxxxxxxxxxxxxxxxx; pebolle@xxxxxxxxxx; Liu, > Chuansheng; Zhang, Dongxing > Subject: Re: [PATCH v3] modify the IO_TLB_SEGSIZE and > IO_TLB_DEFAULT_SIZE configurable as flexible requirement about SW- > IOMMU. > > On Mon, Feb 16, 2015 at 10:38:18AM +0800, Wang Xiaoming wrote: > > The maximum of SW-IOMMU is limited to 2^11*128 = 256K. > > And the maximum of IO_TLB_DEFAULT_SIZE is limited to (64UL<<20) 64M. > > While in different platform and different requirement this seems improper. > > So modifing the IO_TLB_SEGSIZE to io_tlb_segsize and > > IO_TLB_DEFAULT_SIZE to io_tlb_default_size which can configure by > BOARD_KERNEL_CMDLINE in BoardConfig.mk. > > Thsi patch does not have anything in BoardConfig.mk. Perhaps remove this. > > Got a couple of things below: > > This can meet different requirement. > > > > Signed-off-by: Chuansheng Liu <chuansheng.liu@xxxxxxxxx> > > Signed-off-by: Zhang Dongxing <dongxing.zhang@xxxxxxxxx> > > Signed-off-by: Wang Xiaoming <xiaoming.wang@xxxxxxxxx> > > --- > > patch v1 make this change at Kconfig > > which needs to edit the .config manually. > > https://lkml.org/lkml/2015/1/25/571 > > > > patch v2 only change IO_TLB_SEGSIZE configurable > > https://lkml.org/lkml/2015/2/5/812 > > > > arch/mips/cavium-octeon/dma-octeon.c | 2 +- > > arch/mips/netlogic/common/nlm-dma.c | 2 +- > > drivers/xen/swiotlb-xen.c | 6 ++-- > > include/linux/swiotlb.h | 8 +---- > > lib/swiotlb.c | 58 +++++++++++++++++++++++++--------- > > 5 files changed, 49 insertions(+), 27 deletions(-) > > > > diff --git a/arch/mips/cavium-octeon/dma-octeon.c > > b/arch/mips/cavium-octeon/dma-octeon.c > > index 3778655..a521af6 100644 > > --- a/arch/mips/cavium-octeon/dma-octeon.c > > +++ b/arch/mips/cavium-octeon/dma-octeon.c > > @@ -312,7 +312,7 @@ void __init plat_swiotlb_setup(void) > > swiotlbsize = 64 * (1<<20); > > #endif > > swiotlb_nslabs = swiotlbsize >> IO_TLB_SHIFT; > > - swiotlb_nslabs = ALIGN(swiotlb_nslabs, IO_TLB_SEGSIZE); > > + swiotlb_nslabs = ALIGN(swiotlb_nslabs, io_tlb_segsize); > > swiotlbsize = swiotlb_nslabs << IO_TLB_SHIFT; > > > > octeon_swiotlb = alloc_bootmem_low_pages(swiotlbsize); > > diff --git a/arch/mips/netlogic/common/nlm-dma.c > > b/arch/mips/netlogic/common/nlm-dma.c > > index f3d4ae8..eeffa8f 100644 > > --- a/arch/mips/netlogic/common/nlm-dma.c > > +++ b/arch/mips/netlogic/common/nlm-dma.c > > @@ -99,7 +99,7 @@ void __init plat_swiotlb_setup(void) > > > > swiotlbsize = 1 << 20; /* 1 MB for now */ > > swiotlb_nslabs = swiotlbsize >> IO_TLB_SHIFT; > > - swiotlb_nslabs = ALIGN(swiotlb_nslabs, IO_TLB_SEGSIZE); > > + swiotlb_nslabs = ALIGN(swiotlb_nslabs, io_tlb_segsize); > > swiotlbsize = swiotlb_nslabs << IO_TLB_SHIFT; > > > > nlm_swiotlb = alloc_bootmem_low_pages(swiotlbsize); > > diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c > > index 810ad41..3b3e9fe 100644 > > --- a/drivers/xen/swiotlb-xen.c > > +++ b/drivers/xen/swiotlb-xen.c > > @@ -164,11 +164,11 @@ xen_swiotlb_fixup(void *buf, size_t size, > unsigned long nslabs) > > dma_addr_t dma_handle; > > phys_addr_t p = virt_to_phys(buf); > > > > - dma_bits = get_order(IO_TLB_SEGSIZE << IO_TLB_SHIFT) + > PAGE_SHIFT; > > + dma_bits = get_order(io_tlb_segsize << IO_TLB_SHIFT) + PAGE_SHIFT; > > > > i = 0; > > do { > > - int slabs = min(nslabs - i, (unsigned long)IO_TLB_SEGSIZE); > > + int slabs = min(nslabs - i, (unsigned long)io_tlb_segsize); > > > > do { > > rc = xen_create_contiguous_region( @@ -187,7 > +187,7 @@ static > > unsigned long xen_set_nslabs(unsigned long nr_tbl) { > > if (!nr_tbl) { > > xen_io_tlb_nslabs = (64 * 1024 * 1024 >> IO_TLB_SHIFT); > > - xen_io_tlb_nslabs = ALIGN(xen_io_tlb_nslabs, > IO_TLB_SEGSIZE); > > + xen_io_tlb_nslabs = ALIGN(xen_io_tlb_nslabs, io_tlb_segsize); > > } else > > xen_io_tlb_nslabs = nr_tbl; > > > > diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index > > e7a018e..13506db 100644 > > --- a/include/linux/swiotlb.h > > +++ b/include/linux/swiotlb.h > > @@ -8,13 +8,7 @@ struct dma_attrs; > > struct scatterlist; > > > > extern int swiotlb_force; > > - > > -/* > > - * Maximum allowable number of contiguous slabs to map, > > - * must be a power of 2. What is the appropriate value ? > > - * The complexity of {map,unmap}_single is linearly dependent on this > value. > > - */ > > -#define IO_TLB_SEGSIZE 128 > > +extern int io_tlb_segsize; > > > > /* > > * log of the size of each IO TLB slab. The number of slabs is > > command line diff --git a/lib/swiotlb.c b/lib/swiotlb.c index > > 4abda07..1db5fc8 100644 > > --- a/lib/swiotlb.c > > +++ b/lib/swiotlb.c > > @@ -56,6 +56,15 @@ > > int swiotlb_force; > > > > /* > > + * Maximum allowable number of contiguous slabs to map, > > + * must be a power of 2. What is the appropriate value ? > > + * define io_tlb_segsize as a parameter > > + * which can be changed dynamically in config file for special usage. > > + * The complexity of {map,unmap}_single is linearly dependent on this > value. > > + */ > > +int io_tlb_segsize = 128; > > + > > +/* > > * Used to do a quick range check in swiotlb_tbl_unmap_single and > > * swiotlb_tbl_sync_single_*, to see if the memory was in fact allocated by > this > > * API. > > @@ -97,12 +106,20 @@ static DEFINE_SPINLOCK(io_tlb_lock); static int > > late_alloc; > > > > static int __init > > +setup_io_tlb_segsize(char *str) > > +{ > > + get_option(&str, &io_tlb_segsize); > > + return 0; > > +} > > +__setup("io_tlb_segsize=", setup_io_tlb_segsize); > > This should be folded in swiotlb=XYZ parsing please. > I am not very clear about this comment. 1, Do you mean it should use early_param instead of __setup? As I known early_param can't help to assign the parameter that we changed at kernel cmdline because we have the default value here. int io_tlb_segsize = 128; unsigned long io_tlb_default_size = (64UL<<20); 2, Or do you mean use iotlbsegsize instead of io_tlb_segsize? > Also you will need to update the Documentaiton/kernel-parameters.txt file. > > > + > > +static int __init > > setup_io_tlb_npages(char *str) > > { > > if (isdigit(*str)) { > > io_tlb_nslabs = simple_strtoul(str, &str, 0); > > - /* avoid tail segment of size < IO_TLB_SEGSIZE */ > > - io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE); > > + /* avoid tail segment of size < io_tlb_segsize */ > > + io_tlb_nslabs = ALIGN(io_tlb_nslabs, io_tlb_segsize); > > } > > if (*str == ',') > > ++str; > > @@ -120,15 +137,26 @@ unsigned long swiotlb_nr_tbl(void) } > > EXPORT_SYMBOL_GPL(swiotlb_nr_tbl); > > > > -/* default to 64MB */ > > -#define IO_TLB_DEFAULT_SIZE (64UL<<20) > > +/* default to 64MB > > + * define io_tlb_default_size as a parameter > > + * which can be changed dynamically in config file for special usage. > > + */ > > +unsigned long io_tlb_default_size = (64UL<<20); > > + > > +static int __init > > + setup_io_tlb_default_size(char *str) { > > + get_option(&str, &io_tlb_default_size); > > + return 0; > > +} > > +__setup("io_tlb_default_size=", setup_io_tlb_default_size); > > Please fold that in swiotlb=XYZ parameter. Make it do all the work. > > > + > > unsigned long swiotlb_size_or_default(void) { > > unsigned long size; > > > > size = io_tlb_nslabs << IO_TLB_SHIFT; > > > > - return size ? size : (IO_TLB_DEFAULT_SIZE); > > + return size ? size : (io_tlb_default_size); > > } > > > > /* Note that this doesn't work with highmem page */ @@ -183,7 +211,7 > > @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, > > int verbose) > > > > /* > > * Allocate and initialize the free list array. This array is used > > - * to find contiguous free memory regions of size up to > IO_TLB_SEGSIZE > > + * to find contiguous free memory regions of size up to > > +io_tlb_segsize > > * between io_tlb_start and io_tlb_end. > > */ > > io_tlb_list = memblock_virt_alloc( > > @@ -193,7 +221,7 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned > long nslabs, int verbose) > > PAGE_ALIGN(io_tlb_nslabs * > sizeof(phys_addr_t)), > > PAGE_SIZE); > > for (i = 0; i < io_tlb_nslabs; i++) { > > - io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE); > > + io_tlb_list[i] = io_tlb_segsize - OFFSET(i, io_tlb_segsize); > > io_tlb_orig_addr[i] = INVALID_PHYS_ADDR; > > } > > io_tlb_index = 0; > > @@ -211,13 +239,13 @@ int __init swiotlb_init_with_tbl(char *tlb, > > unsigned long nslabs, int verbose) void __init swiotlb_init(int > > verbose) { > > - size_t default_size = IO_TLB_DEFAULT_SIZE; > > + size_t default_size = io_tlb_default_size; > > unsigned char *vstart; > > unsigned long bytes; > > > > if (!io_tlb_nslabs) { > > io_tlb_nslabs = (default_size >> IO_TLB_SHIFT); > > - io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE); > > + io_tlb_nslabs = ALIGN(io_tlb_nslabs, io_tlb_segsize); > > } > > > > bytes = io_tlb_nslabs << IO_TLB_SHIFT; @@ -249,7 +277,7 @@ > > swiotlb_late_init_with_default_size(size_t default_size) > > > > if (!io_tlb_nslabs) { > > io_tlb_nslabs = (default_size >> IO_TLB_SHIFT); > > - io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE); > > + io_tlb_nslabs = ALIGN(io_tlb_nslabs, io_tlb_segsize); > > } > > > > /* > > @@ -308,7 +336,7 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned > > long nslabs) > > > > /* > > * Allocate and initialize the free list array. This array is used > > - * to find contiguous free memory regions of size up to > IO_TLB_SEGSIZE > > + * to find contiguous free memory regions of size up to > > +io_tlb_segsize > > * between io_tlb_start and io_tlb_end. > > */ > > io_tlb_list = (unsigned int *)__get_free_pages(GFP_KERNEL, @@ - > 324,7 > > +352,7 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) > > goto cleanup4; > > > > for (i = 0; i < io_tlb_nslabs; i++) { > > - io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE); > > + io_tlb_list[i] = io_tlb_segsize - OFFSET(i, io_tlb_segsize); > > io_tlb_orig_addr[i] = INVALID_PHYS_ADDR; > > } > > io_tlb_index = 0; > > @@ -493,7 +521,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device > > *hwdev, > > > > for (i = index; i < (int) (index + nslots); i++) > > io_tlb_list[i] = 0; > > - for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != > IO_TLB_SEGSIZE - 1) && io_tlb_list[i]; i--) > > + for (i = index - 1; (OFFSET(i, io_tlb_segsize) != > io_tlb_segsize - > > +1) && io_tlb_list[i]; i--) > > io_tlb_list[i] = ++count; > > tlb_addr = io_tlb_start + (index << IO_TLB_SHIFT); > > > > @@ -571,7 +599,7 @@ void swiotlb_tbl_unmap_single(struct device > *hwdev, phys_addr_t tlb_addr, > > */ > > spin_lock_irqsave(&io_tlb_lock, flags); > > { > > - count = ((index + nslots) < ALIGN(index + 1, IO_TLB_SEGSIZE) ? > > + count = ((index + nslots) < ALIGN(index + 1, io_tlb_segsize) ? > > io_tlb_list[index + nslots] : 0); > > /* > > * Step 1: return the slots to the free list, merging the @@ - > 585,7 > > +613,7 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, > phys_addr_t tlb_addr, > > * Step 2: merge the returned slots with the preceding slots, > > * if available (non zero) > > */ > > - for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != > IO_TLB_SEGSIZE -1) && io_tlb_list[i]; i--) > > + for (i = index - 1; (OFFSET(i, io_tlb_segsize) != io_tlb_segsize > > +-1) && io_tlb_list[i]; i--) > > io_tlb_list[i] = ++count; > > } > > spin_unlock_irqrestore(&io_tlb_lock, flags); > > -- > > 1.7.9.5 > >
