kernel/linux.git/arch/powerpc/include/asm/perf_event.h, branch linux-7.0.y

powerpc/perf: Expose Performance Monitor Counter SPR's as part of extended regs

2021-02-08T14:09:44+00:00

Currently Monitor Mode Control Registers and Sampling registers are part of extended regs. Patch adds support to include Performance Monitor Counter Registers (PMC1 to PMC6 ) as part of extended registers. PMCs are saved in the perf interrupt handler as part of per-cpu array 'pmcs' in struct cpu_hw_events. While capturing the register values for extended regs, fetch these saved PMC values. Simplified the PERF_REG_PMU_MASK_300/31 definition to include PMU SPRs MMCR0 to PMC6. Exclude the unsupported SPRs (MMCR3, SIER2, SIER3) from extended mask value for CPU_FTR_ARCH_300 in the new definition. PERF_REG_EXTENDED_MAX is used to check if any index beyond the extended registers is requested in the sample. Have one PERF_REG_EXTENDED_MAX for CPU_FTR_ARCH_300/CPU_FTR_ARCH_31 since perf_reg_validate function already checks the extended mask for the presence of any unsupported register. Signed-off-by: Athira Rajeev Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/1612335337-1888-3-git-send-email-atrajeev@linux.vnet.ibm.com

powerpc/perf: Add support for outputting extended regs in perf intr_regs

2020-08-17T03:11:22+00:00

Add support for perf extended register capability in powerpc. The capability flag PERF_PMU_CAP_EXTENDED_REGS, is used to indicate the PMU which support extended registers. The generic code define the mask of extended registers as 0 for non supported architectures. Patch adds extended regs support for power9 platform by exposing MMCR0, MMCR1 and MMCR2 registers. REG_RESERVED mask needs update to include extended regs. PERF_REG_EXTENDED_MASK, contains mask value of the supported registers, is defined at runtime in the kernel based on platform since the supported registers may differ from one processor version to another and hence the MASK value. With the patch: available registers: r0 r1 r2 r3 r4 r5 r6 r7 r8 r9 r10 r11 r12 r13 r14 r15 r16 r17 r18 r19 r20 r21 r22 r23 r24 r25 r26 r27 r28 r29 r30 r31 nip msr orig_r3 ctr link xer ccr softe trap dar dsisr sier mmcra mmcr0 mmcr1 mmcr2 PERF_RECORD_SAMPLE(IP, 0x1): 4784/4784: 0 period: 1 addr: 0 ... intr regs: mask 0xffffffffffff ABI 64-bit .... r0 0xc00000000012b77c .... r1 0xc000003fe5e03930 .... r2 0xc000000001b0e000 .... r3 0xc000003fdcddf800 .... r4 0xc000003fc7880000 .... r5 0x9c422724be .... r6 0xc000003fe5e03908 .... r7 0xffffff63bddc8706 .... r8 0x9e4 .... r9 0x0 .... r10 0x1 .... r11 0x0 .... r12 0xc0000000001299c0 .... r13 0xc000003ffffc4800 .... r14 0x0 .... r15 0x7fffdd8b8b00 .... r16 0x0 .... r17 0x7fffdd8be6b8 .... r18 0x7e7076607730 .... r19 0x2f .... r20 0xc00000001fc26c68 .... r21 0xc0002041e4227e00 .... r22 0xc00000002018fb60 .... r23 0x1 .... r24 0xc000003ffec4d900 .... r25 0x80000000 .... r26 0x0 .... r27 0x1 .... r28 0x1 .... r29 0xc000000001be1260 .... r30 0x6008010 .... r31 0xc000003ffebb7218 .... nip 0xc00000000012b910 .... msr 0x9000000000009033 .... orig_r3 0xc00000000012b86c .... ctr 0xc0000000001299c0 .... link 0xc00000000012b77c .... xer 0x0 .... ccr 0x28002222 .... softe 0x1 .... trap 0xf00 .... dar 0x0 .... dsisr 0x80000000000 .... sier 0x0 .... mmcra 0x80000000000 .... mmcr0 0x82008090 .... mmcr1 0x1e000000 .... mmcr2 0x0 ... thread: perf:4784 Signed-off-by: Anju T Sudhakar Signed-off-by: Athira Rajeev Tested-by: Nageswara R Sastry Reviewed-by: Madhavan Srinivasan Reviewed-by: Kajol Jain Reviewed-and-tested-by: Ravi Bangoria Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/1596794701-23530-2-git-send-email-atrajeev@linux.vnet.ibm.com

powerpc/perf: Fix missing is_sier_aviable() during build

2020-07-21T14:03:06+00:00

Compilation error: arch/powerpc/perf/perf_regs.c:80:undefined reference to `.is_sier_available' Currently is_sier_available() is part of core-book3s.c, which is added to build based on CONFIG_PPC_PERF_CTRS. A config with CONFIG_PERF_EVENTS and without CONFIG_PPC_PERF_CTRS will have a build break because of missing is_sier_available(). In practice it only breaks when CONFIG_FSL_EMB_PERF_EVENT=n because that also guards the usage of is_sier_available(). That only happens with CONFIG_PPC_BOOK3E_64=y and CONFIG_FSL_SOC_BOOKE=n. Patch adds is_sier_available() in asm/perf_event.h to fix the build break for configs missing CONFIG_PPC_PERF_CTRS. Fixes: 333804dc3b7a ("powerpc/perf: Update perf_regs structure to include SIER") Reported-by: Aneesh Kumar K.V Signed-off-by: Madhavan Srinivasan [mpe: Add detail about CONFIG_FSL_SOC_BOOKE] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200614083604.302611-1-maddy@linux.ibm.com

powerpc: Rename current_stack_pointer() to current_stack_frame()

2020-03-04T11:44:28+00:00

current_stack_pointer(), which was called __get_SP(), used to just return the value in r1. But that caused problems in some cases, so it was turned into a function in commit bfe9a2cfe91a ("powerpc: Reimplement __get_SP() as a function not a define"). Because it's a function in a separate compilation unit to all its callers, it has the effect of causing a stack frame to be created, and then returns the address of that frame. This is good in some cases like those described in the above commit, but in other cases it's overkill, we just need to know what stack page we're on. On some other arches current_stack_pointer is just a register global giving the stack pointer, and we'd like to do that too. So rename our current_stack_pointer() to current_stack_frame() to make that possible. Signed-off-by: Michael Ellerman Reviewed-by: Christophe Leroy Link: https://lore.kernel.org/r/20200220115141.2707-1-mpe@ellerman.id.au

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32+00:00

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman

powerpc/perf: Update perf_regs structure to include SIER

2018-12-20T09:53:11+00:00

On each sample, Sample Instruction Event Register (SIER) content is saved in pt_regs. SIER does not have a entry as-is in the pt_regs but instead, SIER content is saved in the "dar" register of pt_regs. Patch adds another entry to the perf_regs structure to include the "SIER" printing which internally maps to the "dar" of pt_regs. It also check for the SIER availability in the platform and present value accordingly Signed-off-by: Madhavan Srinivasan Signed-off-by: Michael Ellerman

powerpc/bpf: Fix broken uapi for BPF_PROG_TYPE_PERF_EVENT

2018-12-07T12:19:04+00:00

Now that there are different variants of pt_regs for userspace and kernel, the uapi for the BPF_PROG_TYPE_PERF_EVENT program type must be changed by exporting the user_pt_regs structure instead of the pt_regs structure that is in-kernel only. Fixes: 002af9391bfb ("powerpc: Split user/kernel definitions of struct pt_regs") Signed-off-by: Sandipan Das Signed-off-by: Michael Ellerman

powerpc: Rename __get_SP() to current_stack_pointer()

2014-10-15T00:23:20+00:00

Michael points out that __get_SP() is a pretty horrible function name. Let's give it a better name. Signed-off-by: Anton Blanchard Signed-off-by: Michael Ellerman

powerpc: Reimplement __get_SP() as a function not a define

2014-10-15T00:23:19+00:00

Li Zhong points out an issue with our current __get_SP() implementation. If ftrace function tracing is enabled (ie -pg profiling using _mcount) we spill a stack frame on 64bit all the time. If a function calls __get_SP() and later calls a function that is tail call optimised, we will pop the stack frame and the value returned by __get_SP() is no longer valid. An example from Li can be found in save_stack_trace -> save_context_stack: c0000000000432c0 <.save_stack_trace>: c0000000000432c0: mflr r0 c0000000000432c4: std r0,16(r1) c0000000000432c8: stdu r1,-128(r1) <-- stack frame for _mcount c0000000000432cc: std r3,112(r1) c0000000000432d0: bl <._mcount> c0000000000432d4: nop c0000000000432d8: mr r4,r1 <-- __get_SP() c0000000000432dc: ld r5,632(r13) c0000000000432e0: ld r3,112(r1) c0000000000432e4: li r6,1 c0000000000432e8: addi r1,r1,128 <-- pop stack frame c0000000000432ec: ld r0,16(r1) c0000000000432f0: mtlr r0 c0000000000432f4: b <.save_context_stack> <-- tail call optimized save_context_stack ends up with a stack pointer below the current one, and it is likely to be scribbled over. Fix this by making __get_SP() a function which returns the callers stack frame. Also replace inline assembly which grabs the stack pointer in save_stack_trace and show_stack with __get_SP(). This also fixes an issue with perf_arch_fetch_caller_regs(). It currently unwinds the stack once, which will skip a valid stack frame on a leaf function. With the __get_SP() fixes in this patch, we never need to unwind the stack frame to get to the first interesting frame. We have to export __get_SP() because perf_arch_fetch_caller_regs() (which is used in modules) calls it from a header file. Reported-by: Li Zhong Signed-off-by: Anton Blanchard Signed-off-by: Michael Ellerman

powerpc/perf: Move code to select SIAR or pt_regs into perf_read_regs

2012-07-10T09:18:41+00:00

The logic to choose whether to use the SIAR or get the information out of pt_regs is going to get more complicated, so do it once in perf_read_regs. We overload regs->result which is gross but we are already doing it with regs->dsisr. Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt