- 30 Jul, 2018 15 commits
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Michael Ellerman authored
Paul Menzel reported that kmemleak was producing reports such as: unreferenced object 0xc0000000f8b80000 (size 16384): comm "init", pid 1, jiffies 4294937416 (age 312.240s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000d997deb7>] __pud_alloc+0x80/0x190 [<0000000087f2e8a3>] move_page_tables+0xbac/0xdc0 [<00000000091e51c2>] shift_arg_pages+0xc0/0x210 [<00000000ab88670c>] setup_arg_pages+0x22c/0x2a0 [<0000000060871529>] load_elf_binary+0x41c/0x1648 [<00000000ecd9d2d4>] search_binary_handler.part.11+0xbc/0x280 [<0000000034e0cdd7>] __do_execve_file.isra.13+0x73c/0x940 [<000000005f953a6e>] sys_execve+0x58/0x70 [<000000009700a858>] system_call+0x5c/0x70 Indicating that a PUD was being leaked. However what's really happening is that kmemleak is not able to recognise the references from the PGD to the PUD, because they are not fully qualified pointers. We can confirm that in xmon, eg: Find the task struct for pid 1 "init": 0:mon> P task_struct ->thread.ksp PID PPID S P CMD c0000001fe7c0000 c0000001fe803960 1 0 S 13 systemd Dump virtual address 0 to find the PGD: 0:mon> dv 0 c0000001fe7c0000 pgd @ 0xc0000000f8b01000 Dump the memory of the PGD: 0:mon> d c0000000f8b01000 c0000000f8b01000 00000000f8b90000 0000000000000000 |................| c0000000f8b01010 0000000000000000 0000000000000000 |................| c0000000f8b01020 0000000000000000 0000000000000000 |................| c0000000f8b01030 0000000000000000 00000000f8b80000 |................| ^^^^^^^^^^^^^^^^ There we can see the reference to our supposedly leaked PUD. But because it's missing the leading 0xc, kmemleak won't recognise it. We can confirm it's still in use by translating an address that is mapped via it: 0:mon> dv 7fff94000000 c0000001fe7c0000 pgd @ 0xc0000000f8b01000 pgdp @ 0xc0000000f8b01038 = 0x00000000f8b80000 <-- pudp @ 0xc0000000f8b81ff8 = 0x00000000037c4000 pmdp @ 0xc0000000037c5ca0 = 0x00000000fbd89000 ptep @ 0xc0000000fbd89000 = 0xc0800001d5ce0386 Maps physical address = 0x00000001d5ce0000 Flags = Accessed Dirty Read Write The fix is fairly simple. We need to tell kmemleak to ignore PUD allocations and never report them as leaks. We can also tell it not to scan the PGD, because it will never find pointers in there. However it will still notice if we allocate a PGD and then leak it. Reported-by:Paul Menzel <pmenzel@molgen.mpg.de> Signed-off-by:
Michael Ellerman <mpe@ellerman.id.au> Tested-by:
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Christophe Leroy authored
Split asm/tlbflush.h into: asm/nohash/tlbflush.h asm/book3s/32/tlbflush.h asm/book3s/64/tlbflush.h (already existing) Signed-off-by:
Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by:
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Christophe Leroy authored
asm/tlbflush.h is only needed for: - using functions xxx_flush_tlb_xxx() - using MMU_NO_CONTEXT - including asm-generic/pgtable.h Signed-off-by:
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Christophe Leroy authored
mmu-44x.h doesn't need asm/page.h if PAGE_SHIFT are replaced by CONFIG_PPC_XX_PAGES Signed-off-by:
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Christophe Leroy authored
Signed-off-by:
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Christophe Leroy authored
Remove superflous includes and add missing ones Signed-off-by:
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Christophe Leroy authored
PPC_PIN_SIZE is specific to the 44x and is defined in mmu.h Signed-off-by:
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Christophe Leroy authored
set_breakpoint() is only used in process.c so make it static Signed-off-by:
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Christophe Leroy authored
Files not using fixmap consts or functions don't need asm/fixmap.h Signed-off-by:
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Christophe Leroy authored
files not using feature fixup don't need asm/feature-fixups.h files using feature fixup need asm/feature-fixups.h Signed-off-by:
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Christophe Leroy authored
Only include linux/stringify.h is files using __stringify() Signed-off-by:
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Christophe Leroy authored
This patch moves ASM_CONST() and stringify_in_c() into dedicated asm-const.h, then cleans all related inclusions. Signed-off-by:
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Christophe Leroy authored
Signed-off-by:
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Christophe Leroy authored
Files not using cpu_has_feature() don't need cpu_has_feature.h Signed-off-by:
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Christophe Leroy authored
page.h doesn't need kdump.h Signed-off-by:
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- 24 Jul, 2018 25 commits
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Nicholas Piggin authored
This delay was in the very first OPAL console commit 6.5 years ago, and came from the vio hvc driver. The firmware console has hardened sufficiently to remove it. Reviewed-by:
Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by:
Nicholas Piggin <npiggin@gmail.com> Signed-off-by:
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Nicholas Piggin authored
The RAW console does not need writes to be atomic, so relax opal_put_chars to be able to do partial writes, and implement an _atomic variant which does not take a spinlock. This API is used in xmon, so the less locking that is used, the better chance there is that a crash can be debugged. Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by:
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Nicholas Piggin authored
OPAL console writes do not have to synchronously flush firmware / hardware buffers unless they are going through the udbg path. Remove the unconditional flushing from opal_put_chars. Flush if there was no space in the buffer as an optimisation (callers loop waiting for success in that case). udbg flushing is moved to udbg_opal_putc. Signed-off-by:
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Nicholas Piggin authored
opal_put_chars deals with partial writes because in OPALv1, opal_console_write_buffer_space did not work correctly. That firmware is not supported. This reworks the opal_put_chars code to no longer deal with partial writes by turning them into full writes. Partial write handling is still supported in terms of what gets returned to the caller, but it may not go to the console atomically. A warning message is printed in this case. This allows console flushing to be moved out of the opal_write_lock spinlock. That could cause the lock to be held for long periods if the console is busy (especially if it was being spammed by firmware), which is dangerous because the lock is taken by xmon to debug the system. Flushing outside the lock improves the situation a bit. Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by:
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Nicholas Piggin authored
A new console flushing firmware API was introduced to replace event polling loops, and implemented in opal-kmsg with affddff6 ("powerpc/powernv: Add a kmsg_dumper that flushes console output on panic"), to flush the console in the panic path. The OPAL console driver has other situations where interrupts are off and it needs to flush the console synchronously. These still use a polling loop. So move the opal-kmsg flush code to opal_flush_console, and use the new function in opal-kmsg and opal_put_chars. Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by:
Russell Currey <ruscur@russell.cc> Signed-off-by:
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Nicholas Piggin authored
Use the more refined and tested event polling loop from opal_put_chars as the fallback console flush in the opal-kmsg path. This loop is used by the console driver today, whereas the opal-kmsg fallback is not likely to have been used for years. Use WARN_ONCE rather than a printk when the fallback is invoked to prepare for moving the console flush into a common function. Reviewed-by:
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Nicholas Piggin authored
OPAL_CONSOLE_FLUSH is documented as being able to return OPAL_BUSY, so implement the standard OPAL_BUSY handling for it. Reviewed-by:
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Nicholas Piggin authored
The OPAL console driver does not delay in case it gets OPAL_BUSY or OPAL_BUSY_EVENT from firmware. It can't yet be made to sleep because it is called under spinlock, but it can be changed to the standard OPAL_BUSY loop form, and a delay added to keep it from hitting the firmware too frequently. Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by:
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Nicholas Piggin authored
The intention here is to consume and discard the remaining buffer upon error. This works if there has not been a previous partial write. If there has been, then total_len is no longer total number of bytes to copy. total_len is always "bytes left to copy", so it should be added to written bytes. This code may not be exercised any more if partial writes will not be hit, but this is a small bugfix before a larger change. Reviewed-by:
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Mukesh Ojha authored
Fixes: 8034f715 ("powernv/opal-dump: Convert to irq domain") Converts all the return explicit number to a more proper IRQ_HANDLED, which looks proper incase of interrupt handler returning case. Here, It also removes error message like "nobody cared" which was getting unveiled while returning -1 or 0 from handler. Signed-off-by:
Mukesh Ojha <mukesh02@linux.vnet.ibm.com> Reviewed-by:
Vasant Hegde <hegdevasant@linux.vnet.ibm.com> Signed-off-by:
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Mukesh Ojha authored
Moves the return value check of 'opal_dump_info' to a proper place which was previously unnecessarily filling all the dump info even on failure. Signed-off-by:
Stewart Smith <stewart@linux.vnet.ibm.com> Acked-by:
Jeremy Kerr <jk@ozlabs.org> Signed-off-by:
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Cyril Bur authored
Since commit dc310669 ("powerpc: tm: Always use fp_state and vr_state to store live registers") tm_reclaim_thread() doesn't use the parameter anymore, both callers have to bother getting it as they have no need for a struct thread_info either. Just remove it and adjust the callers. Signed-off-by:
Cyril Bur <cyrilbur@gmail.com> Signed-off-by:
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Cyril Bur authored
In commit eb5c3f1c ("powerpc: Always save/restore checkpointed regs during treclaim/trecheckpoint") __tm_recheckpoint was modified to no longer take the second parameter 'unsigned long orig_msr' as part of a TM rewrite to simplify the reclaiming/recheckpointing process. There is a comment in the asm file where the function is delcared which has an incorrect prototype with the 'orig_msr' parameter. This patch corrects the comment. Signed-off-by:
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Simon Guo authored
This patch reworked selftest memcmp_64 so that memcmp selftest can cover more test cases. It adds testcases for: - memcmp over 4K bytes size. - s1/s2 with different/random offset on 16 bytes boundary. - enter/exit_vmx_ops pairness. Signed-off-by:
Simon Guo <wei.guo.simon@gmail.com> [mpe: Add -maltivec to fix build on some toolchains] Signed-off-by:
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Simon Guo authored
This patch is based on the previous VMX patch on memcmp(). To optimize ppc64 memcmp() with VMX instruction, we need to think about the VMX penalty brought with: If kernel uses VMX instruction, it needs to save/restore current thread's VMX registers. There are 32 x 128 bits VMX registers in PPC, which means 32 x 16 = 512 bytes for load and store. The major concern regarding the memcmp() performance in kernel is KSM, who will use memcmp() frequently to merge identical pages. So it will make sense to take some measures/enhancement on KSM to see whether any improvement can be done here. Cyril Bur indicates that the memcmp() for KSM has a higher possibility to fail (unmatch) early in previous bytes in following mail. https://patchwork.ozlabs.org/patch/817322/#1773629 And I am taking a follow-up on this with this patch. Per some testing, it shows KSM memcmp() will fail early at previous 32 bytes. More specifically: - 76% cases will fail/unmatch before 16 bytes; - 83% cases will fail/unmatch before 32 bytes; - 84% cases will fail/unmatch before 64 bytes; So 32 bytes looks a better choice than other bytes for pre-checking. The early failure is also true for memcmp() for non-KSM case. With a non-typical call load, it shows ~73% cases fail before first 32 bytes. This patch adds a 32 bytes pre-checking firstly before jumping into VMX operations, to avoid the unnecessary VMX penalty. It is not limited to KSM case. And the testing shows ~20% improvement on memcmp() average execution time with this patch. And note the 32B pre-checking is only performed when the compare size is long enough (>=4K currently) to allow VMX operation. The detail data and analysis is at: https://github.com/justdoitqd/publicFiles/blob/master/memcmp/README.mdSigned-off-by:
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Simon Guo authored
This patch add VMX primitives to do memcmp() in case the compare size is equal or greater than 4K bytes. KSM feature can benefit from this. Test result with following test program(replace the "^>" with ""): ------ ># cat tools/testing/selftests/powerpc/stringloops/memcmp.c >#include <malloc.h> >#include <stdlib.h> >#include <string.h> >#include <time.h> >#include "utils.h" >#define SIZE (1024 * 1024 * 900) >#define ITERATIONS 40 int test_memcmp(const void *s1, const void *s2, size_t n); static int testcase(void) { char *s1; char *s2; unsigned long i; s1 = memalign(128, SIZE); if (!s1) { perror("memalign"); exit(1); } s2 = memalign(128, SIZE); if (!s2) { perror("memalign"); exit(1); } for (i = 0; i < SIZE; i++) { s1[i] = i & 0xff; s2[i] = i & 0xff; } for (i = 0; i < ITERATIONS; i++) { int ret = test_memcmp(s1, s2, SIZE); if (ret) { printf("return %d at[%ld]! should have returned zero\n", ret, i); abort(); } } return 0; } int main(void) { return test_harness(testcase, "memcmp"); } ------ Without this patch (but with the first patch "powerpc/64: Align bytes before fall back to .Lshort in powerpc64 memcmp()." in the series): 4.726728762 seconds time elapsed ( +- 3.54%) With VMX patch: 4.234335473 seconds time elapsed ( +- 2.63%) There is ~+10% improvement. Testing with unaligned and different offset version (make s1 and s2 shift random offset within 16 bytes) can archieve higher improvement than 10%.. Signed-off-by: -
Simon Guo authored
Some old tool chains don't know about instructions like vcmpequd. This patch adds .long macro for vcmpequd and vcmpequb, which is a preparation to optimize ppc64 memcmp with VMX instructions. Signed-off-by:
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Simon Guo authored
Currently memcmp() 64bytes version in powerpc will fall back to .Lshort (compare per byte mode) if either src or dst address is not 8 bytes aligned. It can be opmitized in 2 situations: 1) if both addresses are with the same offset with 8 bytes boundary: memcmp() can compare the unaligned bytes within 8 bytes boundary firstly and then compare the rest 8-bytes-aligned content with .Llong mode. 2) If src/dst addrs are not with the same offset of 8 bytes boundary: memcmp() can align src addr with 8 bytes, increment dst addr accordingly, then load src with aligned mode and load dst with unaligned mode. This patch optmizes memcmp() behavior in the above 2 situations. Tested with both little/big endian. Performance result below is based on little endian. Following is the test result with src/dst having the same offset case: (a similar result was observed when src/dst having different offset): (1) 256 bytes Test with the existing tools/testing/selftests/powerpc/stringloops/memcmp: - without patch 29.773018302 seconds time elapsed ( +- 0.09% ) - with patch 16.485568173 seconds time elapsed ( +- 0.02% ) -> There is ~+80% percent improvement (2) 32 bytes To observe performance impact on < 32 bytes, modify tools/testing/selftests/powerpc/stringloops/memcmp.c with following: ------- #include <string.h> #include "utils.h" -#define SIZE 256 +#define SIZE 32 #define ITERATIONS 10000 int test_memcmp(const void *s1, const void *s2, size_t n); -------- - Without patch 0.244746482 seconds time elapsed ( +- 0.36%) - with patch 0.215069477 seconds time elapsed ( +- 0.51%) -> There is ～+13% improvement (3) 0~8 bytes To observe <8 bytes performance impact, modify tools/testing/selftests/powerpc/stringloops/memcmp.c with following: ------- #include <string.h> #include "utils.h" -#define SIZE 256 -#define ITERATIONS 10000 +#define SIZE 8 +#define ITERATIONS 1000000 int test_memcmp(const void *s1, const void *s2, size_t n); ------- - Without patch 1.845642503 seconds time elapsed ( +- 0.12% ) - With patch 1.849767135 seconds time elapsed ( +- 0.26% ) -> They are nearly the same. (-0.2%) Signed-off-by: -
Aneesh Kumar K.V authored
This patch adds error reporting to H_ENTER and H_READ hcalls. A failure for both these hcalls are mostly fatal and it would be good to log the failure reason. Signed-off-by:
Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> [mpe: Split out of larger patch] Signed-off-by:
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Aneesh Kumar K.V authored
Switch from printk to pr_fmt() / pr_xxx(). Signed-off-by:
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Aneesh Kumar K.V authored
We do this in some part. This patch make sure we always try to search for hpte without holding lock and redo the compare with lock held once match found. Signed-off-by:
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Aneesh Kumar K.V authored
No functional change Signed-off-by:
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Aneesh Kumar K.V authored
When computing the starting slot number for a hash page table group we used to do this hpte_group = ((hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL; Multiplying with 8 (HPTES_PER_GROUP) imply the last three bits are 0. Hence we really don't need to clear then separately. Signed-off-by:
Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by:
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Aneesh Kumar K.V authored
We do this only with VMEMMAP config so that our page_to_[nid/section] etc are not impacted. Signed-off-by:
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Aneesh Kumar K.V authored
With SPARSEMEM config enabled, we make sure that we don't add sections beyond MAX_PHYSMEM_BITS range. This results in not building vmemmap mapping for range beyond max range. But our memblock layer looks the device tree and create mapping for the full memory range. Prevent this by checking against MAX_PHSYSMEM_BITS when doing memblock_add. We don't do similar check for memeblock_reserve_range. If reserve range is beyond MAX_PHYSMEM_BITS we expect that to be configured with 'nomap'. Any other reserved range should come from existing memblock ranges which we already filtered while adding. This avoids crash as below when running on a system with system ram config above MAX_PHSYSMEM_BITS Unable to handle kernel paging request for data at address 0xc00a001000000440 Faulting instruction address: 0xc000000001034118 cpu 0x0: Vector: 300 (Data Access) at [c00000000124fb30] pc: c000000001034118: __free_pages_bootmem+0xc0/0x1c0 lr: c00000000103b258: free_all_bootmem+0x19c/0x22c sp: c00000000124fdb0 msr: 9000000002001033 dar: c00a001000000440 dsisr: 40000000 current = 0xc00000000120dd00 paca = 0xc000000001f60000^I irqmask: 0x03^I irq_happened: 0x01 pid = 0, comm = swapper [c00000000124fe20] c00000000103b258 free_all_bootmem+0x19c/0x22c [c00000000124fee0] c000000001010a68 mem_init+0x3c/0x5c [c00000000124ff00] c00000000100401c start_kernel+0x298/0x5e4 [c00000000124ff90] c00000000000b57c start_here_common+0x1c/0x520 Signed-off-by:
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