kernel.git/arch/powerpc/platforms/ps3, branch linux-3.19.y

powerpc/mm: don't do tlbie for updatepp request with NO HPTE fault

2014-12-05T05:26:15Z

upatepp can get called for a nohpte fault when we find from the linux page table that the translation was hashed before. In that case we are sure that there is no existing translation, hence we could avoid doing tlbie. We could possibly race with a parallel fault filling the TLB. But that should be ok because updatepp is only ever relaxing permissions. We also look at linux pte permission bits when filling hash pte permission bits. We also hold the linux pte busy bits while inserting/updating a hashpte entry, hence a paralle update of linux pte is not possible. On the other hand mprotect involves ptep_modify_prot_start which cause a hpte invalidate and not updatepp. Performance number: We use randbox_access_bench written by Anton. Kernel with THP disabled and smaller hash page table size. 86.60% random_access_b [kernel.kallsyms] [k] .native_hpte_updatepp 2.10% random_access_b random_access_bench [.] doit 1.99% random_access_b [kernel.kallsyms] [k] .do_raw_spin_lock 1.85% random_access_b [kernel.kallsyms] [k] .native_hpte_insert 1.26% random_access_b [kernel.kallsyms] [k] .native_flush_hash_range 1.18% random_access_b [kernel.kallsyms] [k] .__delay 0.69% random_access_b [kernel.kallsyms] [k] .native_hpte_remove 0.37% random_access_b [kernel.kallsyms] [k] .clear_user_page 0.34% random_access_b [kernel.kallsyms] [k] .__hash_page_64K 0.32% random_access_b [kernel.kallsyms] [k] fast_exception_return 0.30% random_access_b [kernel.kallsyms] [k] .hash_page_mm With Fix: 27.54% random_access_b random_access_bench [.] doit 22.90% random_access_b [kernel.kallsyms] [k] .native_hpte_insert 5.76% random_access_b [kernel.kallsyms] [k] .native_hpte_remove 5.20% random_access_b [kernel.kallsyms] [k] fast_exception_return 5.12% random_access_b [kernel.kallsyms] [k] .__hash_page_64K 4.80% random_access_b [kernel.kallsyms] [k] .hash_page_mm 3.31% random_access_b [kernel.kallsyms] [k] data_access_common 1.84% random_access_b [kernel.kallsyms] [k] .trace_hardirqs_on_caller Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman

powerpc: Remove more traces of bootmem

2014-11-19T10:41:51Z

Although we are now selecting NO_BOOTMEM, we still have some traces of bootmem lying around. That is because even with NO_BOOTMEM there is still a shim that converts bootmem calls into memblock calls, but ultimately we want to remove all traces of bootmem. Most of the patch is conversions from alloc_bootmem() to memblock_virt_alloc(). In general a call such as: p = (struct foo *)alloc_bootmem(x); Becomes: p = memblock_virt_alloc(x, 0); We don't need the cast because memblock_virt_alloc() returns a void *. The alignment value of zero tells memblock to use the default alignment, which is SMP_CACHE_BYTES, the same value alloc_bootmem() uses. We remove a number of NULL checks on the result of memblock_virt_alloc(). That is because memblock_virt_alloc() will panic if it can't allocate, in exactly the same way as alloc_bootmem(), so the NULL checks are and always have been redundant. The memory returned by memblock_virt_alloc() is already zeroed, so we remove several memsets of the result of memblock_virt_alloc(). Finally we convert a few uses of __alloc_bootmem(x, y, MAX_DMA_ADDRESS) to just plain memblock_virt_alloc(). We don't use memblock_alloc_base() because MAX_DMA_ADDRESS is ~0ul on powerpc, so limiting the allocation to that is pointless, 16XB ought to be enough for anyone. Signed-off-by: Michael Ellerman

Merge branch 'topic/get-cpu-var' into next

2014-11-05T10:00:31Z

powerpc: Convert power off logic to pm_power_off

2014-11-03T01:12:51Z

The generic Linux framework to power off the machine is a function pointer called pm_power_off. The trick about this pointer is that device drivers can potentially implement it rather than board files. Today on powerpc we set pm_power_off to invoke our generic full machine power off logic which then calls ppc_md.power_off to invoke machine specific power off. However, when we want to add a power off GPIO via the "gpio-poweroff" driver, this card house falls apart. That driver only registers itself if pm_power_off is NULL to ensure it doesn't override board specific logic. However, since we always set pm_power_off to the generic power off logic (which will just not power off the machine if no ppc_md.power_off call is implemented), we can't implement power off via the generic GPIO power off driver. To fix this up, let's get rid of the ppc_md.power_off logic and just always use pm_power_off as was intended. Then individual drivers such as the GPIO power off driver can implement power off logic via that function pointer. With this patch set applied and a few patches on top of QEMU that implement a power off GPIO on the virt e500 machine, I can successfully turn off my virtual machine after halt. Signed-off-by: Alexander Graf [mpe: Squash into one patch and update changelog based on cover letter] Signed-off-by: Michael Ellerman

powerpc: Replace __get_cpu_var uses

2014-11-03T01:12:32Z

This still has not been merged and now powerpc is the only arch that does not have this change. Sorry about missing linuxppc-dev before. V2->V2 - Fix up to work against 3.18-rc1 __get_cpu_var() is used for multiple purposes in the kernel source. One of them is address calculation via the form &__get_cpu_var(x). This calculates the address for the instance of the percpu variable of the current processor based on an offset. Other use cases are for storing and retrieving data from the current processors percpu area. __get_cpu_var() can be used as an lvalue when writing data or on the right side of an assignment. __get_cpu_var() is defined as : __get_cpu_var() always only does an address determination. However, store and retrieve operations could use a segment prefix (or global register on other platforms) to avoid the address calculation. this_cpu_write() and this_cpu_read() can directly take an offset into a percpu area and use optimized assembly code to read and write per cpu variables. This patch converts __get_cpu_var into either an explicit address calculation using this_cpu_ptr() or into a use of this_cpu operations that use the offset. Thereby address calculations are avoided and less registers are used when code is generated. At the end of the patch set all uses of __get_cpu_var have been removed so the macro is removed too. The patch set includes passes over all arches as well. Once these operations are used throughout then specialized macros can be defined in non -x86 arches as well in order to optimize per cpu access by f.e. using a global register that may be set to the per cpu base. Transformations done to __get_cpu_var() 1. Determine the address of the percpu instance of the current processor. DEFINE_PER_CPU(int, y); int *x = &__get_cpu_var(y); Converts to int *x = this_cpu_ptr(&y); 2. Same as #1 but this time an array structure is involved. DEFINE_PER_CPU(int, y[20]); int *x = __get_cpu_var(y); Converts to int *x = this_cpu_ptr(y); 3. Retrieve the content of the current processors instance of a per cpu variable. DEFINE_PER_CPU(int, y); int x = __get_cpu_var(y) Converts to int x = __this_cpu_read(y); 4. Retrieve the content of a percpu struct DEFINE_PER_CPU(struct mystruct, y); struct mystruct x = __get_cpu_var(y); Converts to memcpy(&x, this_cpu_ptr(&y), sizeof(x)); 5. Assignment to a per cpu variable DEFINE_PER_CPU(int, y) __get_cpu_var(y) = x; Converts to __this_cpu_write(y, x); 6. Increment/Decrement etc of a per cpu variable DEFINE_PER_CPU(int, y); __get_cpu_var(y)++ Converts to __this_cpu_inc(y) Cc: Benjamin Herrenschmidt CC: Paul Mackerras Signed-off-by: Christoph Lameter [mpe: Fix build errors caused by set/or_softirq_pending(), and rework assignment in __set_breakpoint() to use memcpy().] Signed-off-by: Michael Ellerman

Merge branch 'powernv-cpuidle' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

2014-04-02T20:47:29Z

Pull powerpc non-virtualized cpuidle from Ben Herrenschmidt: "This is the branch I mentioned in my other pull request which contains our improved cpuidle support for the "powernv" platform (non-virtualized). It adds support for the "fast sleep" feature of the processor which provides higher power savings than our usual "nap" mode but at the cost of losing the timers while asleep, and thus exploits the new timer broadcast framework to work around that limitation. It's based on a tip timer tree that you seem to have already merged" * 'powernv-cpuidle' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: cpuidle/powernv: Parse device tree to setup idle states cpuidle/powernv: Add "Fast-Sleep" CPU idle state powerpc/powernv: Add OPAL call to resync timebase on wakeup powerpc/powernv: Add context management for Fast Sleep powerpc: Split timer_interrupt() into timer handling and interrupt handling routines powerpc: Implement tick broadcast IPI as a fixed IPI message powerpc: Free up the slot of PPC_MSG_CALL_FUNC_SINGLE IPI message

powerpc: Implement tick broadcast IPI as a fixed IPI message

2014-03-05T04:55:04Z

For scalability and performance reasons, we want the tick broadcast IPIs to be handled as efficiently as possible. Fixed IPI messages are one of the most efficient mechanisms available - they are faster than the smp_call_function mechanism because the IPI handlers are fixed and hence they don't involve costly operations such as adding IPI handlers to the target CPU's function queue, acquiring locks for synchronization etc. Luckily we have an unused IPI message slot, so use that to implement tick broadcast IPIs efficiently. Signed-off-by: Srivatsa S. Bhat [Functions renamed to tick_broadcast* and Changelog modified by Preeti U. Murthy] Signed-off-by: Preeti U. Murthy Acked-by: Geoff Levand [For the PS3 part] Signed-off-by: Benjamin Herrenschmidt

powerpc: Free up the slot of PPC_MSG_CALL_FUNC_SINGLE IPI message

2014-03-05T04:53:24Z

The IPI handlers for both PPC_MSG_CALL_FUNC and PPC_MSG_CALL_FUNC_SINGLE map to a common implementation - generic_smp_call_function_single_interrupt(). So, we can consolidate them and save one of the IPI message slots, (which are precious on powerpc, since only 4 of those slots are available). So, implement the functionality of PPC_MSG_CALL_FUNC_SINGLE using PPC_MSG_CALL_FUNC itself and release its IPI message slot, so that it can be used for something else in the future, if desired. Signed-off-by: Srivatsa S. Bhat Signed-off-by: Preeti U. Murthy Acked-by: Geoff Levand [For the PS3 part] Signed-off-by: Benjamin Herrenschmidt

usb: host: remove selects of USB_ARCH_HAS_?HCI

2014-02-18T20:36:38Z

USB_ARCH_HAS_EHCI, USB_ARCH_HAS_OHCI, and USB_ARCH_HAS_XHCI were just removed. Selecting them is a nop. The select statements for these symbols can be removed too. Signed-off-by: Paul Bolle Acked-by: Alan Stern Signed-off-by: Greg Kroah-Hartman

powerpc/ps3: Remove inline marking of EXPORT_SYMBOL functions

2013-12-02T03:06:53Z

EXPORT_SYMBOL and inline directives are contradictory to each other. The patch fixes this inconsistency. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Denis Efremov Acked-by: Geoff Levand Signed-off-by: Benjamin Herrenschmidt