5d2efba64b
The 10Gigabit ethernet device drivers appear to be able to chew up all 256MB of TCE mappings on pSeries systems, as evidenced by numerous error messages: iommu_alloc failed, tbl c0000000010d5c48 vaddr c0000000d875eff0 npages 1 Some experimentation indicates that this is essentially because one 1500 byte ethernet MTU gets mapped as a 64K DMA region when the large 64K pages are enabled. Thus, it doesn't take much to exhaust all of the available DMA mappings for a high-speed card. This patch changes the iommu allocator to work with its own unique, distinct page size. Although the patch is long, its actually quite simple: it just #defines a distinct IOMMU_PAGE_SIZE and then uses this in all the places that matter. As a side effect, it also dramatically improves network performance on platforms with H-calls on iommu translation inserts/removes (since we no longer call it 16 times for a 1500 bytes packet when the iommu HW is still 4k). In the future, we might want to make the IOMMU_PAGE_SIZE a variable in the iommu_table instance, thus allowing support for different HW page sizes in the iommu itself. Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Paul Mackerras <paulus@samba.org> |
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| .. | ||
| call_hpt.h | ||
| call_pci.h | ||
| call_sm.h | ||
| dt.c | ||
| htab.c | ||
| hvcall.S | ||
| hvlog.c | ||
| hvlpconfig.c | ||
| iommu.c | ||
| ipl_parms.h | ||
| irq.c | ||
| irq.h | ||
| it_exp_vpd_panel.h | ||
| it_lp_naca.h | ||
| Kconfig | ||
| ksyms.c | ||
| lpardata.c | ||
| lpevents.c | ||
| main_store.h | ||
| Makefile | ||
| mf.c | ||
| misc.S | ||
| naca.h | ||
| pci.c | ||
| pci.h | ||
| proc.c | ||
| processor_vpd.h | ||
| release_data.h | ||
| setup.c | ||
| setup.h | ||
| smp.c | ||
| smp.h | ||
| spcomm_area.h | ||
| viopath.c | ||
| vpd_areas.h | ||
| vpdinfo.c | ||