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author | Chris Metcalf <cmetcalf@tilera.com> | 2012-03-29 13:58:43 -0400 |
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committer | Chris Metcalf <cmetcalf@tilera.com> | 2012-05-25 12:48:24 -0400 |
commit | d5d14ed6f2db7287a5088e1350cf422bf72140b3 (patch) | |
tree | 19f0bc20bb6f1995a1e4f75dc58e388c047f7d23 /arch/tile/Kconfig | |
parent | 47d632f9f8f3ed62b21f725e98b726d65769b6d7 (diff) | |
download | linux-d5d14ed6f2db7287a5088e1350cf422bf72140b3.tar.bz2 |
arch/tile: Allow tilegx to build with either 16K or 64K page size
This change introduces new flags for the hv_install_context()
API that passes a page table pointer to the hypervisor. Clients
can explicitly request 4K, 16K, or 64K small pages when they
install a new context. In practice, the page size is fixed at
kernel compile time and the same size is always requested every
time a new page table is installed.
The <hv/hypervisor.h> header changes so that it provides more abstract
macros for managing "page" things like PFNs and page tables. For
example there is now a HV_DEFAULT_PAGE_SIZE_SMALL instead of the old
HV_PAGE_SIZE_SMALL. The various PFN routines have been eliminated and
only PA- or PTFN-based ones remain (since PTFNs are always expressed
in fixed 2KB "page" size). The page-table management macros are
renamed with a leading underscore and take page-size arguments with
the presumption that clients will use those macros in some single
place to provide the "real" macros they will use themselves.
I happened to notice the old hv_set_caching() API was totally broken
(it assumed 4KB pages) so I changed it so it would nominally work
correctly with other page sizes.
Tag modules with the page size so you can't load a module built with
a conflicting page size. (And add a test for SMP while we're at it.)
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Diffstat (limited to 'arch/tile/Kconfig')
-rw-r--r-- | arch/tile/Kconfig | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/arch/tile/Kconfig b/arch/tile/Kconfig index 74239dd77e06..38c3957e0b40 100644 --- a/arch/tile/Kconfig +++ b/arch/tile/Kconfig @@ -139,6 +139,31 @@ config NR_CPUS smaller kernel memory footprint results from using a smaller value on chips with fewer tiles. +if TILEGX + +choice + prompt "Kernel page size" + default PAGE_SIZE_64KB + help + This lets you select the page size of the kernel. For best + performance on memory-intensive applications, a page size of 64KB + is recommended. For workloads involving many small files, many + connections, etc., it may be better to select 16KB, which uses + memory more efficiently at some cost in TLB performance. + + Note that this option is TILE-Gx specific; currently + TILEPro page size is set by rebuilding the hypervisor. + +config PAGE_SIZE_16KB + bool "16KB" + +config PAGE_SIZE_64KB + bool "64KB" + +endchoice + +endif + source "kernel/time/Kconfig" source "kernel/Kconfig.hz" |