- 16 Jan, 2018 26 commits
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Benjamin Herrenschmidt authored
WORD2 if the TIMA isn't byte accessible and isn't that useful to know about, take out the pr_devel statement. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Benjamin Herrenschmidt authored
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Benjamin Herrenschmidt authored
We used to not put the newline between the CPU part and the summary part on UP kernels. This is a rather pointless ifdef so take it out. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Benjamin Herrenschmidt authored
These adapters can be found in a number of our systems, so let's enable the corresponding drivers by default. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Christophe Leroy authored
When CONFIG_SWAP is set, the TLB miss handlers have to also take into account _PAGE_ACCESSED flag. At the moment it is done by anding _PAGE_ACCESSED into _PAGE_PRESENT using 3 instructions. This patch uses APG for handling _PAGE_ACCESSED, allowing to just copy _PAGE_ACCESSED bit into APG field, hence reducing the action to a single instruction. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Christophe Leroy authored
As Linux kernel separates KERNEL and USER address spaces, there is therefore no need to flag USER access at page level. Today, the 8xx TLB handlers already handle user access in the L1 entry through Access Protection Groups, it is then natural to move the user access handling at PMD level once _PAGE_NA allows to handle PAGE_NONE protection without _PAGE_USER In the mean time, as we free up one bit in the PTE, we can use it to include SPS (page size flag) in the PTE and avoid handling it at every TLB miss hence removing special handling based on compiled page size. For _PAGE_EXEC, we rework it to use PP PTE bits, avoiding the copy of _PAGE_EXEC bit into the L1 entry. Unfortunatly we are not able to put it at the correct location as it conflicts with NA/RO/RW bits for data entries. Upper bits of APG in L1 entry overlap with PMD base address. In order to avoid having to filter that out, we set up all groups so that upper bits can have any value. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Christophe Leroy authored
Today, PAGE_NONE is defined as a page not having _PAGE_USER. In some circunstances, when the CPU supports it, it might be better to be able to flag a page with NO ACCESS. In a following patch, the 8xx will switch user access being flagged in the PMD, therefore it will not be possible anymore to use _PAGE_USER as a way to flag a page with no access. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Christophe Leroy authored
commit ac29c640 ("powerpc/mm: Replace _PAGE_USER with _PAGE_PRIVILEGED") introduced _PAGE_PRIVILEGED for BOOK3S/64 This patch generalises _PAGE_PRIVILEGED for all CPUs, allowing to have either _PAGE_PRIVILEGED or _PAGE_USER or both. PPC_8xx has a _PAGE_SHARED flag which is set for and only for all non user pages. Lets rename it _PAGE_PRIVILEGED to remove confusion as it has nothing to do with Linux shared pages. On BookE, there's a _PAGE_BAP_SR which has to be set for kernel pages: defining _PAGE_PRIVILEGED as _PAGE_BAP_SR will make this generic Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Christophe Leroy authored
_PAGE_WRITETHRU is only used in: * AMIGA_Z2RAM block driver which is never activated on powerPC * Video/FB driver which is for PPC_PMAC Therefore, no need to spend time in 8xx TLB miss handlers for handling it. And by removing it, we free up bit 20 which then avoids having to clear it on each TLB miss. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Christophe Leroy authored
In TLB miss handlers, updating the perf counter is only useful when performing a perf analysis. As it has a noticeable overhead, let's only do it when needed. In order to do so, the exit of the miss handlers will be patched when starting/stopping 'perf': the first register restore instruction of each exit point will be replaced by a jump to the counting code. Once this is done, CONFIG_PPC_8xx_PERF_EVENT becomes useless as this feature doesn't add any overhead. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Christophe Leroy authored
EXCEPTION_PROLOG_0 and EXCEPTION_EPILOG_0 were added some time ago in order to regroup the two mtspr/mfspr to SCRATCH0 and SCRATCH1 and the mfcr/mtcr in order to ease entry and exit of function not using the full EXCEPTION_PROLOG. Since then, the mfcr/mtcr has been taken out, hence just leaving the two mtspr/mfspr in the macro. In order to improve readability of the exception functions, we remove those two macros and copy back the two mtspr/mfspr instead. As r10 and r11 are used for SCRATCH0 and SCRATCH1, lets also use r12 for SCRATCH2. It will also improve the readability/maintenance. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Christophe Leroy authored
CPU6 ERRATA affects only MPC860 revisions prior to C.0. Manufacturing of those revisiosn was stopped in 1999-2000. Therefore, it has been almost 20 years since this ERRATA has been fixed in the silicon. This patch removes the workaround for that ERRATA. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Christophe Leroy authored
Since commit 0e6e01ff ("CPM/QE: use genalloc to manage CPM/QE muram"), rheap is not used anymore. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Balbir Singh authored
Certain HMI's such as malfunction error propagate through all threads/core on the system. If a thread was offline prior to us crashing the system and jumping to the kdump kernel, bad things happen when it wakes up due to an HMI in the kdump kernel. There are several possible ways to solve this problem 1. Put the offline cores in a state such that they are not woken up for machine check and HMI errors. This does not work, since we might need to wake up offline threads to handle TB errors 2. Ignore HMI errors, setup HMEER to mask HMI errors, but this still leads the window open for any MCEs and masking them for the duration of the dump might be a concern 3. Wake up offline CPUs, as in send them to crash_ipi_callback (not wake them up as in mark them online as seen by the hotplug). kexec does a wake_online_cpus() call, this patch does something similar, but instead sends an IPI and forces them to crash_ipi_callback() This patch takes approach #3. Care is taken to enable this only for powenv platforms via crash_wake_offline (a global value set at setup time). The crash code sends out IPI's to all CPU's which then move to crash_ipi_callback and kexec_smp_wait(). Signed-off-by: Balbir Singh <bsingharora@gmail.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Balbir Singh authored
Our check was extra cautious, we've audited crash_send_ipi and it sends an IPI only to online CPU's. Removal of this check should have not functional impact on crash kdump. Signed-off-by: Balbir Singh <bsingharora@gmail.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Dmitry Torokhov authored
Instead of manually coding the loop with of_find_node_by_type(), let's switch to the standard macro for iterating over nodes with given type. Also fixed a couple of refcount leaks in the aforementioned loops. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Christophe Leroy authored
This patch remove CONFIG_PPC_HTDUMP if not PPC_BOOK3S_64 to avoid below compile failure on BOOK3S_32: In file included from arch/powerpc/mm/dump_hashpagetable.c:27:0: ./arch/powerpc/include/asm/plpar_wrappers.h: In function 'get_cede_latency_hint': ./arch/powerpc/include/asm/plpar_wrappers.h:27:2: error: implicit declaration of function 'get_lppaca' [-Werror=implicit-function-declaration] ... arch/powerpc/mm/dump_hashpagetable.c: At top level: arch/powerpc/mm/dump_hashpagetable.c:69:13: error: 'SLB_VSID_B' undeclared here (not in a function) ... arch/powerpc/mm/dump_hashpagetable.c:506:38: error: 'VMEMMAP_BASE' undeclared (first use in this function) arch/powerpc/mm/dump_hashpagetable.c:506:35: error: assignment makes integer from pointer without a cast [-Werror] Fixes: dd5ac03e ("powerpc/mm: Fix page table dump build on non-Book3S") Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> [mpe: Trim change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Nathan Fontenot authored
Add required bits to the architecture vector to enable support of the ibm,dynamic-memory-v2 device tree property. Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Nathan Fontenot authored
The Power Hypervisor has introduced a new device tree format for the property describing the dynamic reconfiguration LMBs for a system, ibm,dynamic-memory-v2. This new format condenses the size of the property, especially on large memory systems, by reporting sets of LMBs that have the same properties (flags and associativity array index). This patch updates the powerpc/mm/drmem.c code to provide routines that can parse the new device tree format during the walk_drmem_lmb* routines used during boot, the creation of the LMB array, and updating the device tree to create a new property in the proper format for ibm,dynamic-memory-v2. Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Nathan Fontenot authored
Now that the powerpc code parses dynamic reconfiguration memory LMB information from the LMB array and not the device tree directly we can move the of_drconf_cell struct to drmem.h where it fits better. In addition, the struct is renamed to of_drconf_cell_v1 in anticipation of upcoming support for version 2 of the dynamic reconfiguration property and the members are typed as __be* values to reflect how they exist in the device tree. Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Nathan Fontenot authored
Update the pseries memory hotplug code to use the newly added dynamic reconfiguration LMB array. Doing this is required for the upcoming support of version 2 of the dynamic reconfiguration device tree property. In addition, making this change cleans up the code that parses the LMB information as we no longer need to worry about device tree format. This allows us to discard one of the first steps on memory hotplug where we make a working copy of the device tree property and convert the entire property to cpu format. Instead we just use the LMB array directly while holding the memory hotplug lock. This patch also moves the updating of the device tree property to powerpc/mm/drmem.c. This allows to the hotplug code to work without needing to know the device tree format and provides a single routine for updating the device tree property. This new routine will handle determination of the proper device tree format and generate a properly formatted device tree property. Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Nathan Fontenot authored
Update code in powerpc/numa.c to use the walk_drmem_lmbs() routine instead of parsing the device tree directly. This is in anticipation of introducing a new ibm,dynamic-memory-v2 property with a different format. This will allow the numa code to use a single initialization routine per-LMB irregardless of the device tree format. Additionally, to support additional routines in numa.c that need to look up LMB information, an late_init routine is added to drmem.c to allocate the array of LMB information. This LMB array will provide per-LMB information to separate the LMB data from the device tree format. Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Nathan Fontenot authored
We currently have code to parse the dynamic reconfiguration LMB information from the ibm,dynamic-meory device tree property in multiple locations; numa.c, prom.c, and pseries/hotplug-memory.c. In anticipation of adding support for a version 2 of the ibm,dynamic-memory property this patch aims to separate the device tree information from the device tree format. Doing this requires a two step process to avoid a possibly very large bootmem allocation early in boot. During initial boot, new routines are provided to walk the device tree property and make a call-back for each LMB. The second step (introduced in later patches) will allocate an array of LMB information that can be used directly without needing to know the DT format. This approach provides the benefit of consolidating the device tree property parsing to a single location and (eventually) providing a common data structure for retrieving LMB information. This patch introduces a routine to walk the ibm,dynamic-memory property in the flattened device tree and updates the prom.c code to use this to initialize memory. Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Nathan Fontenot authored
Look up the associativity arrays in of_drconf_to_nid_single when deriving the nid for a LMB instead of having it passed in as a parameter. Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Nathan Fontenot authored
Look up the device node for the usable memory property instead of having it passed in as a parameter. This changes precedes an update in which the calling routines for of_get_usable_memory() will not have the device node pointer to pass in. Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Nathan Fontenot authored
Look up the device node for the associativity array property instead of having it passed in as a parameter. This changes precedes an update in which the calling routines for of_get_assoc_arrays() will not have the device node pointer to pass in. Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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- 03 Jan, 2018 1 commit
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Michael Ellerman authored
Add a test case of the error code reported when we take a SEGV on a mapped but inaccessible area. We broke this recently. Based on a test case from John Sperbeck <jsperbeck@google.com>. Acked-by: John Sperbeck <jsperbeck@google.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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- 22 Dec, 2017 3 commits
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Aneesh Kumar K.V authored
pte_access_premitted get called in get_user_pages_fast path. If we have marked the pte PROT_NONE, we should not allow a read access on the address. With the current implementation we are not checking the READ and only check for WRITE. This is needed on archs like ppc64 that implement PROT_NONE using _PAGE_USER access instead of _PAGE_PRESENT. Also add pte_user check just to make sure we are not accessing kernel mapping. Even though there is code duplication, keeping the low level pte accessors different for different platforms helps in code readability. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Aneesh Kumar K.V authored
pte_access_premitted get called in get_user_pages_fast path. If we have marked the pte PROT_NONE, we should not allow a read access on the address. With the current implementation we are not checking the READ and only check for WRITE. This is needed on archs like ppc64 that implement PROT_NONE using RWX access instead of _PAGE_PRESENT. Also add pte_user check just to make sure we are not accessing kernel mapping. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Aneesh Kumar K.V authored
No functional change in this patch. This update gup_hugepte to use the helper. This will help later when we add memory keys. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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- 20 Dec, 2017 8 commits
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Ram Pai authored
The H_PAGE_F_SECOND,H_PAGE_F_GIX are not in the 64K main-PTE. capture these changes in the dump pte report. Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Ram Pai authored
replace redundant code in __hash_page_4K() and flush_hash_page() with helper functions pte_get_hash_gslot() and pte_set_hidx() Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Ram Pai authored
We need PTE bits 3 ,4, 5, 6 and 57 to support protection-keys, because these are the bits we want to consolidate on across all configuration to support protection keys. Bit 3,4,5 and 6 are currently used on 4K-pte kernels. But bit 9 and 10 are available. Hence we use the two available bits and free up bit 5 and 6. We will still not be able to free up bit 3 and 4. In the absence of any other free bits, we will have to stay satisfied with what we have :-(. This means we will not be able to support 32 protection keys, but only 8. The bit numbers are big-endian as defined in the ISA3.0 This patch does the following change to 4K PTE. H_PAGE_F_SECOND (S) which occupied bit 4 moves to bit 7. H_PAGE_F_GIX (G,I,X) which occupied bit 5, 6 and 7 also moves to bit 8,9, 10 respectively. H_PAGE_HASHPTE (H) which occupied bit 8 moves to bit 4. Before the patch, the 4k PTE format was as follows 0 1 2 3 4 5 6 7 8 9 10....................57.....63 : : : : : : : : : : : : : v v v v v v v v v v v v v ,-,-,-,-,--,--,--,--,-,-,-,-,-,------------------,-,-,-, |x|x|x|B|S |G |I |X |H| | |x|x|................| |x|x|x| '_'_'_'_'__'__'__'__'_'_'_'_'_'________________'_'_'_'_' After the patch, the 4k PTE format is as follows 0 1 2 3 4 5 6 7 8 9 10....................57.....63 : : : : : : : : : : : : : v v v v v v v v v v v v v ,-,-,-,-,--,--,--,--,-,-,-,-,-,------------------,-,-,-, |x|x|x|B|H | | |S |G|I|X|x|x|................| |.|.|.| '_'_'_'_'__'__'__'__'_'_'_'_'_'________________'_'_'_'_' The patch has no code changes; just swizzles around bits. Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Ram Pai authored
0xf is considered invalid hidx value. It indicates absence of a backing HPTE. A PTE is initialized to 0xf either a) when it is new it is newly allocated to hold 4k-backing-HPTE or b) Any time it gets demoted to a 4k-backing-HPTE This patch shifts the representation by one-modulo-0xf; i.e hidx 0 is represented as 1, 1 as 2,... , and 0xf as 0. This convention lets us initialize the secondary-part of the PTE to all zeroes. PTEs are anyway zero'd when allocated. We do not have to zero them again; thus saving on the initialization. Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Ram Pai authored
Rearrange 64K PTE bits to free up bits 3, 4, 5 and 6 in the 64K backed HPTE pages. This along with the earlier patch will entirely free up the four bits from 64K PTE. The bit numbers are big-endian as defined in the ISA3.0 This patch does the following change to 64K PTE backed by 64K HPTE. H_PAGE_F_SECOND (S) which occupied bit 4 moves to the second part of the pte to bit 60. H_PAGE_F_GIX (G,I,X) which occupied bit 5, 6 and 7 also moves to the second part of the pte to bit 61, 62, 63, 64 respectively since bit 7 is now freed up, we move H_PAGE_BUSY (B) from bit 9 to bit 7. The second part of the PTE will hold (H_PAGE_F_SECOND|H_PAGE_F_GIX) at bit 60,61,62,63. NOTE: None of the bits in the secondary PTE were not used by 64k-HPTE backed PTE. Before the patch, the 64K HPTE backed 64k PTE format was as follows 0 1 2 3 4 5 6 7 8 9 10...........................63 : : : : : : : : : : : : v v v v v v v v v v v v ,-,-,-,-,--,--,--,--,-,-,-,-,-,------------------,-,-,-, |x|x|x| |S |G |I |X |x|B| |x|x|................|x|x|x|x| <- primary pte '_'_'_'_'__'__'__'__'_'_'_'_'_'________________'_'_'_'_' | | | | | | | | | | | | |..................| | | | | <- secondary pte '_'_'_'_'__'__'__'__'_'_'_'_'__________________'_'_'_'_' After the patch, the 64k HPTE backed 64k PTE format is as follows 0 1 2 3 4 5 6 7 8 9 10...........................63 : : : : : : : : : : : : v v v v v v v v v v v v ,-,-,-,-,--,--,--,--,-,-,-,-,-,------------------,-,-,-, |x|x|x| | | | |B |x| | |x|x|................|.|.|.|.| <- primary pte '_'_'_'_'__'__'__'__'_'_'_'_'_'________________'_'_'_'_' | | | | | | | | | | | | |..................|S|G|I|X| <- secondary pte '_'_'_'_'__'__'__'__'_'_'_'_'__________________'_'_'_'_' The above PTE changes is applicable to hugetlbpages aswell. The patch does the following code changes: a) moves the H_PAGE_F_SECOND and H_PAGE_F_GIX to 4k PTE header since it is no more needed b the 64k PTEs. b) abstracts out __real_pte() and __rpte_to_hidx() so the caller need not know the bit location of the slot. c) moves the slot bits to the secondary pte. Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Ram Pai authored
Rearrange 64K PTE bits to free up bits 3, 4, 5 and 6, in the 4K backed HPTE pages.These bits continue to be used for 64K backed HPTE pages in this patch, but will be freed up in the next patch. The bit numbers are big-endian as defined in the ISA3.0 The patch does the following change to the 4k HTPE backed 64K PTE's format. H_PAGE_BUSY moves from bit 3 to bit 9 (B bit in the figure below) V0 which occupied bit 4 is not used anymore. V1 which occupied bit 5 is not used anymore. V2 which occupied bit 6 is not used anymore. V3 which occupied bit 7 is not used anymore. Before the patch, the 4k backed 64k PTE format was as follows 0 1 2 3 4 5 6 7 8 9 10...........................63 : : : : : : : : : : : : v v v v v v v v v v v v ,-,-,-,-,--,--,--,--,-,-,-,-,-,------------------,-,-,-, |x|x|x|B|V0|V1|V2|V3|x| | |x|x|................|x|x|x|x| <- primary pte '_'_'_'_'__'__'__'__'_'_'_'_'_'________________'_'_'_'_' |S|G|I|X|S |G |I |X |S|G|I|X|..................|S|G|I|X| <- secondary pte '_'_'_'_'__'__'__'__'_'_'_'_'__________________'_'_'_'_' After the patch, the 4k backed 64k PTE format is as follows 0 1 2 3 4 5 6 7 8 9 10...........................63 : : : : : : : : : : : : v v v v v v v v v v v v ,-,-,-,-,--,--,--,--,-,-,-,-,-,------------------,-,-,-, |x|x|x| | | | | |x|B| |x|x|................|.|.|.|.| <- primary pte '_'_'_'_'__'__'__'__'_'_'_'_'_'________________'_'_'_'_' |S|G|I|X|S |G |I |X |S|G|I|X|..................|S|G|I|X| <- secondary pte '_'_'_'_'__'__'__'__'_'_'_'_'__________________'_'_'_'_' the four bits S,G,I,X (one quadruplet per 4k HPTE) that cache the hash-bucket slot value, is initialized to 1,1,1,1 indicating -- an invalid slot. If a HPTE gets cached in a 1111 slot(i.e 7th slot of secondary hash bucket), it is released immediately. In other words, even though 1111 is a valid slot value in the hash bucket, we consider it invalid and release the slot and the HPTE. This gives us the opportunity to determine the validity of S,G,I,X bits based on its contents and not on any of the bits V0,V1,V2 or V3 in the primary PTE When we release a HPTE cached in the 1111 slot we also release a legitimate slot in the primary hash bucket and unmap its corresponding HPTE. This is to ensure that we do get a HPTE cached in a slot of the primary hash bucket, the next time we retry. Though treating 1111 slot as invalid, reduces the number of available slots in the hash bucket and may have an effect on the performance, the probabilty of hitting a 1111 slot is extermely low. Compared to the current scheme, the above scheme reduces the number of false hash table updates significantly and has the added advantage of releasing four valuable PTE bits for other purpose. NOTE:even though bits 3, 4, 5, 6, 7 are not used when the 64K PTE is backed by 4k HPTE, they continue to be used if the PTE gets backed by 64k HPTE. The next patch will decouple that aswell, and truely release the bits. This idea was jointly developed by Paul Mackerras, Aneesh, Michael Ellermen and myself. 4K PTE format remains unchanged currently. The patch does the following code changes a) PTE flags are split between 64k and 4k header files. b) __hash_page_4K() is reimplemented to reflect the above logic. Acked-by: Balbir Singh <bsingharora@gmail.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Ram Pai authored
Introduce pte_get_hash_gslot()() which returns the global slot number of the HPTE in the global hash table. This function will come in handy as we work towards re-arranging the PTE bits in the later patches. Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Ram Pai authored
Introduce pte_set_hidx().It sets the (H_PAGE_F_SECOND|H_PAGE_F_GIX) bits at the appropriate location in the PTE of 4K PTE. For 64K PTE, it sets the bits in the second part of the PTE. Though the implementation for the former just needs the slot parameter, it does take some additional parameters to keep the prototype consistent. This function will be handy as we work towards re-arranging the bits in the subsequent patches. Acked-by: Balbir Singh <bsingharora@gmail.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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- 11 Dec, 2017 2 commits
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Simon Guo authored
GCC 7 will take "r2" in clobber list as an error and it will get following build errors for powerpc ptrace selftests even with -fno-pic option: ptrace-tm-vsx.c: In function ‘tm_vsx’: ptrace-tm-vsx.c:42:2: error: PIC register clobbered by ‘r2’ in ‘asm’ asm __volatile__( ^~~ make[1]: *** [ptrace-tm-vsx] Error 1 ptrace-tm-spd-vsx.c: In function ‘tm_spd_vsx’: ptrace-tm-spd-vsx.c:55:2: error: PIC register clobbered by ‘r2’ in ‘asm’ asm __volatile__( ^~~ make[1]: *** [ptrace-tm-spd-vsx] Error 1 ptrace-tm-spr.c: In function ‘tm_spr’: ptrace-tm-spr.c:46:2: error: PIC register clobbered by ‘r2’ in ‘asm’ asm __volatile__( ^~~ Fix the build error by removing "r2" from the clobber list. None of these asm blocks actually clobber r2. Reported-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> Tested-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Bryant G. Ly authored
Add a pci_vf_drivers_autoprobe() interface. Setting autoprobe to false on the PF prevents drivers from binding to VFs when they are enabled. Signed-off-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com> Signed-off-by: Juan J. Alvarez <jjalvare@linux.vnet.ibm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Russell Currey <ruscur@russell.cc> Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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