- 08 Jun, 2023 19 commits
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Vincent Chen authored
This patch adds vector context save/restore for guest VCPUs. To reduce the impact on KVM performance, the implementation imitates the FP context switch mechanism to lazily store and restore the vector context only when the kernel enters/exits the in-kernel run loop and not during the KVM world switch. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Anup Patel <anup@brainfault.org> Acked-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20230605110724.21391-20-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Vincent Chen authored
Add V extension to KVM isa extension list to enable supporting of V extension on VCPUs. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Anup Patel <anup@brainfault.org> Acked-by: Anup Patel <anup@brainfault.org> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230605110724.21391-19-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Greentime Hu authored
Early function calls, such as setup_vm(), relocate_enable_mmu(), soc_early_init() etc, are free to operate on stack. However, PT_SIZE_ON_STACK bytes at the head of the kernel stack are purposedly reserved for the placement of per-task register context pointed by task_pt_regs(p). Those functions may corrupt task_pt_regs if we overlap the $sp with it. In fact, we had accidentally corrupted sstatus.VS in some tests, treating the kernel to save V context before V was actually allocated, resulting in a kernel panic. Thus, we should skip PT_SIZE_ON_STACK for $sp before making C function calls from the top-level assembly. Co-developed-by: ShihPo Hung <shihpo.hung@sifive.com> Signed-off-by: ShihPo Hung <shihpo.hung@sifive.com> Co-developed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230605110724.21391-18-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Andy Chiu authored
Some extensions, such as Vector, dynamically change footprint on a signal frame, so MINSIGSTKSZ is no longer accurate. For example, an RV64V implementation with vlen = 512 may occupy 2K + 40 + 12 Bytes of a signal frame with the upcoming support. And processes that do not execute any vector instructions do not need to reserve the extra sigframe. So we need a way to guard the allocation size of the sigframe at process runtime according to current status of V. Thus, provide the function sigaltstack_size_valid() to validate its size based on current allocation status of supported extensions. Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230605110724.21391-17-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Vincent Chen authored
The vector register belongs to the signal context. They need to be stored and restored as entering and leaving the signal handler. According to the V-extension specification, the maximum length of the vector registers can be 2^16. Hence, if userspace refers to the MINSIGSTKSZ to create a sigframe, it may not be enough. To resolve this problem, this patch refers to the commit 94b07c1f ("arm64: signal: Report signal frame size to userspace via auxv") to enable userspace to know the minimum required sigframe size through the auxiliary vector and use it to allocate enough memory for signal context. Note that auxv always reports size of the sigframe as if V exists for all starting processes, whenever the kernel has CONFIG_RISCV_ISA_V. The reason is that users usually reference this value to allocate an alternative signal stack, and the user may use V anytime. So the user must reserve a space for V-context in sigframe in case that the signal handler invokes after the kernel allocating V. Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Acked-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Björn Töpel <bjorn@rivosinc.com> Reviewed-by: Guo Ren <guoren@kernel.org> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230605110724.21391-16-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Greentime Hu authored
This patch facilitates the existing fp-reserved words for placement of the first extension's context header on the user's sigframe. A context header consists of a distinct magic word and the size, including the header itself, of an extension on the stack. Then, the frame is followed by the context of that extension, and then a header + context body for another extension if exists. If there is no more extension to come, then the frame must be ended with a null context header. A special case is rv64gc, where the kernel support no extensions requiring to expose additional regfile to the user. In such case the kernel would place the null context header right after the first reserved word of __riscv_q_ext_state when saving sigframe. And the kernel would check if all reserved words are zeros when a signal handler returns. __riscv_q_ext_state---->| |<-__riscv_extra_ext_header ~ ~ .reserved[0]--->|0 |<- .reserved <-------|magic |<- .hdr | |size |_______ end of sc_fpregs | |ext-bdy| | ~ ~ +)size ------->|magic |<- another context header |size | |ext-bdy| ~ ~ |magic:0|<- null context header |size:0 | The vector registers will be saved in datap pointer. The datap pointer will be allocated dynamically when the task needs in kernel space. On the other hand, datap pointer on the sigframe will be set right after the __riscv_v_ext_state data structure. Co-developed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Suggested-by: Vineet Gupta <vineetg@rivosinc.com> Suggested-by: Richard Henderson <richard.henderson@linaro.org> Co-developed-by: Andy Chiu <andy.chiu@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Acked-by: Conor Dooley <conor.dooley@microchip.com> Acked-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230605110724.21391-15-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Andy Chiu authored
In order to let kernel/user locate and identify an extension context on the existing sigframe, we are going to utilize reserved space of fp and encode the information there. And since the sigcontext has already preserved a space for fp context w or w/o CONFIG_FPU, we move those reserved words checking/setting routine back into generic code. This commit also undone an additional logical change carried by the refactor commit 007f5c35 ("Refactor FPU code in signal setup/return procedures"). Originally we did not restore fp context if restoring of gpr have failed. And it was fine on the other side. In such way the kernel could keep the regfiles intact, and potentially react at the failing point of restore. Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Acked-by: Conor Dooley <conor.dooley@microchip.com> Acked-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230605110724.21391-14-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Greentime Hu authored
This patch adds ptrace support for riscv vector. The vector registers will be saved in datap pointer of __riscv_v_ext_state. This pointer will be set right after the __riscv_v_ext_state data structure then it will be put in ubuf for ptrace system call to get or set. It will check if the datap got from ubuf is set to the correct address or not when the ptrace system call is trying to set the vector registers. Co-developed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-13-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Andy Chiu authored
Vector unit is disabled by default for all user processes. Thus, a process will take a trap (illegal instruction) into kernel at the first time when it uses Vector. Only after then, the kernel allocates V context and starts take care of the context for that user process. Suggested-by: Richard Henderson <richard.henderson@linaro.org> Link: https://lore.kernel.org/r/3923eeee-e4dc-0911-40bf-84c34aee962d@linaro.orgSigned-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230605110724.21391-12-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Greentime Hu authored
This patch adds task switch support for vector. It also supports all lengths of vlen. Suggested-by: Andrew Waterman <andrew@sifive.com> Co-developed-by: Nick Knight <nick.knight@sifive.com> Signed-off-by: Nick Knight <nick.knight@sifive.com> Co-developed-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Co-developed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Co-developed-by: Ruinland Tsai <ruinland.tsai@sifive.com> Signed-off-by: Ruinland Tsai <ruinland.tsai@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Vineet Gupta <vineetg@rivosinc.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Björn Töpel <bjorn@rivosinc.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230605110724.21391-11-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Greentime Hu authored
Add vector state context struct to be added later in thread_struct. And prepare low-level helper functions to save/restore vector contexts. This include Vector Regfile and CSRs holding dynamic configuration state (vstart, vl, vtype, vcsr). The Vec Register width could be implementation defined, but same for all processes, so that is saved separately. This is not yet wired into final thread_struct - will be done when __switch_to actually starts doing this in later patches. Given the variable (and potentially large) size of regfile, they are saved in dynamically allocated memory, pointed to by datap pointer in __riscv_v_ext_state. Co-developed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Vineet Gupta <vineetg@rivosinc.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Acked-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Guo Ren <guoren@kernel.org> Reviewed-by: Björn Töpel <bjorn@rivosinc.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-10-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Greentime Hu authored
This patch is used to detect the size of CPU vector registers and use riscv_v_vsize to save the size of all the vector registers. It assumes all harts has the same capabilities in a SMP system. If a core detects VLENB that is different from the boot core, then it warns and turns off V support for user space. Co-developed-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Co-developed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-9-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Greentime Hu authored
These are small and likely to be frequently called so implement as inline routines (vs. function call). Co-developed-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Co-developed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Vineet Gupta <vineetg@rivosinc.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-8-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Guo Ren authored
Disable vector instructions execution for kernel mode at its entrances. This helps find illegal uses of vector in the kernel space, which is similar to the fpu. Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Co-developed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Co-developed-by: Han-Kuan Chen <hankuan.chen@sifive.com> Signed-off-by: Han-Kuan Chen <hankuan.chen@sifive.com> Co-developed-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Vineet Gupta <vineetg@rivosinc.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-7-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Greentime Hu authored
clear vector registers on boot if kernel supports V. Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Vineet Gupta <vineetg@rivosinc.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Acked-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-6-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Greentime Hu authored
Follow the riscv vector spec to add new csr numbers. Acked-by: Guo Ren <guoren@kernel.org> Co-developed-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Co-developed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Suggested-by: Vineet Gupta <vineetg@rivosinc.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230605110724.21391-5-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Andy Chiu authored
Probing kernel support for Vector extension is available now. This only add detection for V only. Extenions like Zvfh, Zk are not in this scope. Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Evan Green <evan@rivosinc.com> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-4-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Guo Ren authored
Add V-extension into riscv_isa_ext_keys array and detect it with isa string parsing. Signed-off-by: Guo Ren <ren_guo@c-sky.com> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Suggested-by: Vineet Gupta <vineetg@rivosinc.com> Co-developed-by: Andy Chiu <andy.chiu@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-3-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Guo Ren authored
The name of __switch_to_aux() is not clear and rename it with the determine function: __switch_to_fpu(). Next we could add other regs' switch. Signed-off-by: Guo Ren <ren_guo@c-sky.com> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Reviewed-by: Anup Patel <anup@brainfault.org> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230605110724.21391-2-andy.chiu@sifive.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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- 07 May, 2023 8 commits
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Linus Torvalds authored
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Linus Torvalds authored
Merge tag 'perf-tools-for-v6.4-3-2023-05-06' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux Pull perf tool updates from Arnaldo Carvalho de Melo: "Third version of perf tool updates, with the build problems with with using a 'vmlinux.h' generated from the main build fixed, and the bpf skeleton build disabled by default. Build: - Require libtraceevent to build, one can disable it using NO_LIBTRACEEVENT=1. It is required for tools like 'perf sched', 'perf kvm', 'perf trace', etc. libtraceevent is available in most distros so installing 'libtraceevent-devel' should be a one-time event to continue building perf as usual. Using NO_LIBTRACEEVENT=1 produces tooling that is functional and sufficient for lots of users not interested in those libtraceevent dependent features. - Allow Python support in 'perf script' when libtraceevent isn't linked, as not all features requires it, for instance Intel PT does not use tracepoints. - Error if the python interpreter needed for jevents to work isn't available and NO_JEVENTS=1 isn't set, preventing a build without support for JSON vendor events, which is a rare but possible condition. The two check error messages: $(error ERROR: No python interpreter needed for jevents generation. Install python or build with NO_JEVENTS=1.) $(error ERROR: Python interpreter needed for jevents generation too old (older than 3.6). Install a newer python or build with NO_JEVENTS=1.) - Make libbpf 1.0 the minimum required when building with out of tree, distro provided libbpf. - Use libsdtc++'s and LLVM's libcxx's __cxa_demangle, a portable C++ demangler, add 'perf test' entry for it. - Make binutils libraries opt in, as distros disable building with it due to licensing, they were used for C++ demangling, for instance. - Switch libpfm4 to opt-out rather than opt-in, if libpfm-devel (or equivalent) isn't installed, we'll just have a build warning: Makefile.config:1144: libpfm4 not found, disables libpfm4 support. Please install libpfm4-dev - Add a feature test for scandirat(), that is not implemented so far in musl and uclibc, disabling features that need it, such as scanning for tracepoints in /sys/kernel/tracing/events. perf BPF filters: - New feature where BPF can be used to filter samples, for instance: $ sudo ./perf record -e cycles --filter 'period > 1000' true $ sudo ./perf script perf-exec 2273949 546850.708501: 5029 cycles: ffffffff826f9e25 finish_wait+0x5 ([kernel.kallsyms]) perf-exec 2273949 546850.708508: 32409 cycles: ffffffff826f9e25 finish_wait+0x5 ([kernel.kallsyms]) perf-exec 2273949 546850.708526: 143369 cycles: ffffffff82b4cdbf xas_start+0x5f ([kernel.kallsyms]) perf-exec 2273949 546850.708600: 372650 cycles: ffffffff8286b8f7 __pagevec_lru_add+0x117 ([kernel.kallsyms]) perf-exec 2273949 546850.708791: 482953 cycles: ffffffff829190de __mod_memcg_lruvec_state+0x4e ([kernel.kallsyms]) true 2273949 546850.709036: 501985 cycles: ffffffff828add7c tlb_gather_mmu+0x4c ([kernel.kallsyms]) true 2273949 546850.709292: 503065 cycles: 7f2446d97c03 _dl_map_object_deps+0x973 (/usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2) - In addition to 'period' (PERF_SAMPLE_PERIOD), the other PERF_SAMPLE_ can be used for filtering, and also some other sample accessible values, from tools/perf/Documentation/perf-record.txt: Essentially the BPF filter expression is: <term> <operator> <value> (("," | "||") <term> <operator> <value>)* The <term> can be one of: ip, id, tid, pid, cpu, time, addr, period, txn, weight, phys_addr, code_pgsz, data_pgsz, weight1, weight2, weight3, ins_lat, retire_lat, p_stage_cyc, mem_op, mem_lvl, mem_snoop, mem_remote, mem_lock, mem_dtlb, mem_blk, mem_hops The <operator> can be one of: ==, !=, >, >=, <, <=, & The <value> can be one of: <number> (for any term) na, load, store, pfetch, exec (for mem_op) l1, l2, l3, l4, cxl, io, any_cache, lfb, ram, pmem (for mem_lvl) na, none, hit, miss, hitm, fwd, peer (for mem_snoop) remote (for mem_remote) na, locked (for mem_locked) na, l1_hit, l1_miss, l2_hit, l2_miss, any_hit, any_miss, walk, fault (for mem_dtlb) na, by_data, by_addr (for mem_blk) hops0, hops1, hops2, hops3 (for mem_hops) perf lock contention: - Show lock type with address. - Track and show mmap_lock, siglock and per-cpu rq_lock with address. This is done for mmap_lock by following the current->mm pointer: $ sudo ./perf lock con -abl -- sleep 10 contended total wait max wait avg wait address symbol ... 16344 312.30 ms 2.22 ms 19.11 us ffff8cc702595640 17686 310.08 ms 1.49 ms 17.53 us ffff8cc7025952c0 3 84.14 ms 45.79 ms 28.05 ms ffff8cc78114c478 mmap_lock 3557 76.80 ms 68.75 us 21.59 us ffff8cc77ca3af58 1 68.27 ms 68.27 ms 68.27 ms ffff8cda745dfd70 9 54.53 ms 7.96 ms 6.06 ms ffff8cc7642a48b8 mmap_lock 14629 44.01 ms 60.00 us 3.01 us ffff8cc7625f9ca0 3481 42.63 ms 140.71 us 12.24 us ffffffff937906ac vmap_area_lock 16194 38.73 ms 42.15 us 2.39 us ffff8cd397cbc560 11 38.44 ms 10.39 ms 3.49 ms ffff8ccd6d12fbb8 mmap_lock 1 5.43 ms 5.43 ms 5.43 ms ffff8cd70018f0d8 1674 5.38 ms 422.93 us 3.21 us ffffffff92e06080 tasklist_lock 581 4.51 ms 130.68 us 7.75 us ffff8cc9b1259058 5 3.52 ms 1.27 ms 703.23 us ffff8cc754510070 112 3.47 ms 56.47 us 31.02 us ffff8ccee38b3120 381 3.31 ms 73.44 us 8.69 us ffffffff93790690 purge_vmap_area_lock 255 3.19 ms 36.35 us 12.49 us ffff8d053ce30c80 - Update default map size to 16384. - Allocate single letter option -M for --map-nr-entries, as it is proving being frequently used. - Fix struct rq lock access for older kernels with BPF's CO-RE (Compile once, run everywhere). - Fix problems found with MSAn. perf report/top: - Add inline information when using --call-graph=fp or lbr, as was already done to the --call-graph=dwarf callchain mode. - Improve the 'srcfile' sort key performance by really using an optimization introduced in 6.2 for the 'srcline' sort key that avoids calling addr2line for comparision with each sample. perf sched: - Make 'perf sched latency/map/replay' to use "sched:sched_waking" instead of "sched:sched_waking", consistent with 'perf record' since d566a9c2 ("perf sched: Prefer sched_waking event when it exists"). perf ftrace: - Make system wide the default target for latency subcommand, run the following command then generate some network traffic and press control+C: # perf ftrace latency -T __kfree_skb ^C DURATION | COUNT | GRAPH | 0 - 1 us | 27 | ############# | 1 - 2 us | 22 | ########### | 2 - 4 us | 8 | #### | 4 - 8 us | 5 | ## | 8 - 16 us | 24 | ############ | 16 - 32 us | 2 | # | 32 - 64 us | 1 | | 64 - 128 us | 0 | | 128 - 256 us | 0 | | 256 - 512 us | 0 | | 512 - 1024 us | 0 | | 1 - 2 ms | 0 | | 2 - 4 ms | 0 | | 4 - 8 ms | 0 | | 8 - 16 ms | 0 | | 16 - 32 ms | 0 | | 32 - 64 ms | 0 | | 64 - 128 ms | 0 | | 128 - 256 ms | 0 | | 256 - 512 ms | 0 | | 512 - 1024 ms | 0 | | 1 - ... s | 0 | | # perf top: - Add --branch-history (LBR: Last Branch Record) option, just like already available for 'perf record'. - Fix segfault in thread__comm_len() where thread->comm was being used outside thread->comm_lock. perf annotate: - Allow configuring objdump and addr2line in ~/.perfconfig., so that you can use alternative binaries, such as llvm's. perf kvm: - Add TUI mode for 'perf kvm stat report'. Reference counting: - Add reference count checking infrastructure to check for use after free, done to the 'cpumap', 'namespaces', 'maps' and 'map' structs, more to come. To build with it use -DREFCNT_CHECKING=1 in the make command line to build tools/perf. Documented at: https://perf.wiki.kernel.org/index.php/Reference_Count_Checking - The above caught, for instance, fix, present in this series: - Fix maps use after put in 'perf test "Share thread maps"': 'maps' is copied from leader, but the leader is put on line 79 and then 'maps' is used to read the reference count below - so a use after put, with the put of maps happening within thread__put. Fixed by reversing the order of puts so that the leader is put last. - Also several fixes were made to places where reference counts were not being held. - Make this one of the tests in 'make -C tools/perf build-test' to regularly build test it and to make sure no direct access to the reference counted structs are made, doing that via accessors to check the validity of the struct pointer. ARM64: - Fix 'perf report' segfault when filtering coresight traces by sparse lists of CPUs. - Add support for 'simd' as a sort field for 'perf report', to show ARM's NEON SIMD's predicate flags: "partial" and "empty". arm64 vendor events: - Add N1 metrics. Intel vendor events: - Add graniterapids, grandridge and sierraforrest events. - Refresh events for: alderlake, aldernaken, broadwell, broadwellde, broadwellx, cascadelakx, haswell, haswellx, icelake, icelakex, jaketown, meteorlake, knightslanding, sandybridge, sapphirerapids, silvermont, skylake, tigerlake and westmereep-dp - Refresh metrics for alderlake-n, broadwell, broadwellde, broadwellx, haswell, haswellx, icelakex, ivybridge, ivytown and skylakex. perf stat: - Implement --topdown using JSON metrics. - Add TopdownL1 JSON metric as a default if present, but disable it for now for some Intel hybrid architectures, a series of patches addressing this is being reviewed and will be submitted for v6.5. - Use metrics for --smi-cost. - Update topdown documentation. Vendor events (JSON) infrastructure: - Add support for computing and printing metric threshold values. For instance, here is one found in thesapphirerapids json file: { "BriefDescription": "Percentage of cycles spent in System Management Interrupts.", "MetricExpr": "((msr@aperf@ - cycles) / msr@aperf@ if msr@smi@ > 0 else 0)", "MetricGroup": "smi", "MetricName": "smi_cycles", "MetricThreshold": "smi_cycles > 0.1", "ScaleUnit": "100%" }, - Test parsing metric thresholds with the fake PMU in 'perf test pmu-events'. - Support for printing metric thresholds in 'perf list'. - Add --metric-no-threshold option to 'perf stat'. - Add rand (reverse and) and has_pmem (optane memory) support to metrics. - Sort list of input files to avoid depending on the order from readdir() helping in obtaining reproducible builds. S/390: - Add common metrics: - CPI (cycles per instruction), prbstate (ratio of instructions executed in problem state compared to total number of instructions), l1mp (Level one instruction and data cache misses per 100 instructions). - Add cache metrics for z13, z14, z15 and z16. - Add metric for TLB and cache. ARM: - Add raw decoding for SPE (Statistical Profiling Extension) v1.3 MTE (Memory Tagging Extension) and MOPS (Memory Operations) load/store. Intel PT hardware tracing: - Add event type names UINTR (User interrupt delivered) and UIRET (Exiting from user interrupt routine), documented in table 32-50 "CFE Packet Type and Vector Fields Details" in the Intel Processor Trace chapter of The Intel SDM Volume 3 version 078. - Add support for new branch instructions ERETS and ERETU. - Fix CYC timestamps after standalone CBR ARM CoreSight hardware tracing: - Allow user to override timestamp and contextid settings. - Fix segfault in dso lookup. - Fix timeless decode mode detection. - Add separate decode paths for timeless and per-thread modes. auxtrace: - Fix address filter entire kernel size. Miscellaneous: - Fix use-after-free and unaligned bugs in the PLT handling routines. - Use zfree() to reduce chances of use after free. - Add missing 0x prefix for addresses printed in hexadecimal in 'perf probe'. - Suppress massive unsupported target platform errors in the unwind code. - Fix return incorrect build_id size in elf_read_build_id(). - Fix 'perf scripts intel-pt-events.py' IPC output for Python 2 . - Add missing new parameter in kfree_skb tracepoint to the python scripts using it. - Add 'perf bench syscall fork' benchmark. - Add support for printing PERF_MEM_LVLNUM_UNC (Uncached access) in 'perf mem'. - Fix wrong size expectation for perf test 'Setup struct perf_event_attr' caused by the patch adding perf_event_attr::config3. - Fix some spelling mistakes" * tag 'perf-tools-for-v6.4-3-2023-05-06' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (365 commits) Revert "perf build: Make BUILD_BPF_SKEL default, rename to NO_BPF_SKEL" Revert "perf build: Warn for BPF skeletons if endian mismatches" perf metrics: Fix SEGV with --for-each-cgroup perf bpf skels: Stop using vmlinux.h generated from BTF, use subset of used structs + CO-RE perf stat: Separate bperf from bpf_profiler perf test record+probe_libc_inet_pton: Fix call chain match on x86_64 perf test record+probe_libc_inet_pton: Fix call chain match on s390 perf tracepoint: Fix memory leak in is_valid_tracepoint() perf cs-etm: Add fix for coresight trace for any range of CPUs perf build: Fix unescaped # in perf build-test perf unwind: Suppress massive unsupported target platform errors perf script: Add new parameter in kfree_skb tracepoint to the python scripts using it perf script: Print raw ip instead of binary offset for callchain perf symbols: Fix return incorrect build_id size in elf_read_build_id() perf list: Modify the warning message about scandirat(3) perf list: Fix memory leaks in print_tracepoint_events() perf lock contention: Rework offset calculation with BPF CO-RE perf lock contention: Fix struct rq lock access perf stat: Disable TopdownL1 on hybrid perf stat: Avoid SEGV on counter->name ...
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull debugobjects fix from Thomas Gleixner: "A single fix for debugobjects: The recent fix to ensure atomicity of lookup and allocation inadvertently broke the pool refill mechanism, so that debugobject OOMs now in certain situations. The reason is that the functions which got updated no longer invoke debug_objecs_init(), which is now the only place to care about refilling the tracking object pool. Restore the original behaviour by adding explicit refill opportunities to those places" * tag 'core-debugobjects-2023-05-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: debugobject: Ensure pool refill (again)
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git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6Linus Torvalds authored
Pull crypto fixes from Herbert Xu: - A long-standing bug in crypto_engine - A buggy but harmless check in the sun8i-ss driver - A regression in the CRYPTO_USER interface * tag 'v6.4-p2' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: crypto: api - Fix CRYPTO_USER checks for report function crypto: engine - fix crypto_queue backlog handling crypto: sun8i-ss - Fix a test in sun8i_ss_setup_ivs()
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git://git.samba.org/sfrench/cifs-2.6Linus Torvalds authored
Pull cifs fixes from Steve French: "smb3 client fixes, mostly DFS or reconnect related: - Two DFS connection sharing fixes - DFS refresh fix - Reconnect fix - Two potential use after free fixes - Also print prefix patch in mount debug msg - Two small cleanup fixes" * tag '6.4-rc-smb3-client-fixes-part2' of git://git.samba.org/sfrench/cifs-2.6: cifs: Remove unneeded semicolon cifs: fix sharing of DFS connections cifs: avoid potential races when handling multiple dfs tcons cifs: protect access of TCP_Server_Info::{origin,leaf}_fullpath cifs: fix potential race when tree connecting ipc cifs: fix potential use-after-free bugs in TCP_Server_Info::hostname cifs: print smb3_fs_context::source when mounting cifs: protect session status check in smb2_reconnect() SMB3.1.1: correct definition for app_instance_id create contexts
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git://git.kernel.org/pub/scm/linux/kernel/git/clk/linuxLinus Torvalds authored
Pull clk fixes from Stephen Boyd: "A couple more patches that would be good to get into -rc1: - Revert an i.MX patch that's causing video failures because division math goes sideways - Fix a clang + W=1 build isue where FIELD_PREP() is taking a 32-bit variable instead of the usual u64 type - Fix a Kconfig bug in the StarFive JH7110 clk config that selects a reset controller when it can't be selected" * tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: clk: starfive: Fix RESET_STARFIVE_JH7110 can't be selected in a specified case clk: sp7021: Adjust width of _m in HWM_FIELD_PREP() Revert "clk: imx: composite-8m: Add support to determine_rate"
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git://git.linaro.org/landing-teams/working/fujitsu/integrationLinus Torvalds authored
Pull mailbox updates from Jassi Brar: - mailbox api: allow direct registration to a channel and convert omap and pcc to use mbox_bind_client - omap and hi6220 : use of_property_read_bool - test: fix double-free and use spinlock header - rockchip and bcm-pdc: drop of_match_ptr - mpfs: change config symbol - mediatek gce: support MT6795 - qcom apcs: consolidate of_device_id and support IPQ9574 * tag 'mailbox-v6.4' of git://git.linaro.org/landing-teams/working/fujitsu/integration: dt-bindings: mailbox: qcom: add compatible for IPQ9574 SoC mailbox: qcom-apcs-ipc: do not grow the of_device_id dt-bindings: mailbox: qcom,apcs-kpss-global: use fallbacks for few variants dt-bindings: mailbox: mediatek,gce-mailbox: Add support for MT6795 mailbox: mpfs: convert SOC_MICROCHIP_POLARFIRE to ARCH_MICROCHIP_POLARFIRE mailbox: bcm-pdc: drop of_match_ptr for ID table mailbox: rockchip: drop of_match_ptr for ID table mailbox: mailbox-test: Fix potential double-free in mbox_test_message_write() mailbox: mailbox-test: Explicitly include header for spinlock support mailbox: Use of_property_read_bool() for boolean properties mailbox: pcc: Use mbox_bind_client mailbox: omap: Use mbox_bind_client mailbox: Allow direct registration to a channel
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git://git.kernel.dk/linuxLinus Torvalds authored
Pull more io_uring updates from Jens Axboe: "Nothing major in here, just two different parts: - A small series from Breno that enables passing the full SQE down for ->uring_cmd(). This is a prerequisite for enabling full network socket operations. Queued up a bit late because of some stylistic concerns that got resolved, would be nice to have this in 6.4-rc1 so the dependent work will be easier to handle for 6.5. - Fix for the huge page coalescing, which was a regression introduced in the 6.3 kernel release (Tobias)" * tag 'for-6.4/io_uring-2023-05-07' of git://git.kernel.dk/linux: io_uring: Remove unnecessary BUILD_BUG_ON io_uring: Pass whole sqe to commands io_uring: Create a helper to return the SQE size io_uring/rsrc: check for nonconsecutive pages
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- 06 May, 2023 13 commits
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Arnaldo Carvalho de Melo authored
This reverts commit a980755b. We need to better polish building with BPF skels, so revert back to making it an experimental feature that has to be explicitely enabled using BUILD_BPF_SKEL=1. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Arnaldo Carvalho de Melo authored
This reverts commit 51924ae6. We need to better polish building with BPF skels, so revert back to making it an experimental feature that has to be explicitely enabled using BUILD_BPF_SKEL=1. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mmLinus Torvalds authored
Pull dmapool updates - again - from Andrew Morton: "Reinstate the dmapool changes which were accidentally removed by a mishap on the last commit in the previous attempt at the series" Fixes: 2d55c16c ("dmapool: create/destroy cleanup"). [ The whole old series: def85743..2d55c16c results in an empty diff because that last commit ended up being just a revert of all that came everything before it. - Linus ] * tag 'mm-stable-2023-05-06-10-49' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: dmapool: link blocks across pages dmapool: don't memset on free twice dmapool: simplify freeing dmapool: consolidate page initialization dmapool: rearrange page alloc failure handling dmapool: move debug code to own functions dmapool: speedup DMAPOOL_DEBUG with init_on_alloc dmapool: cleanup integer types dmapool: use sysfs_emit() instead of scnprintf() dmapool: remove checks for dev == NULL
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Linus Torvalds authored
Merge tag 'mm-hotfixes-stable-2023-05-06-10-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull hotfixes from Andrew Morton: "Five hotfixes. Three are cc:stable, two pertain to merge window changes" * tag 'mm-hotfixes-stable-2023-05-06-10-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: afs: fix the afs_dir_get_folio return value nilfs2: do not write dirty data after degenerating to read-only mm: do not reclaim private data from pinned page nilfs2: fix infinite loop in nilfs_mdt_get_block() mm/mmap/vma_merge: always check invariants
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Keith Busch authored
The allocated dmapool pages are never freed for the lifetime of the pool. There is no need for the two level list+stack lookup for finding a free block since nothing is ever removed from the list. Just use a simple stack, reducing time complexity to constant. The implementation inserts the stack linking elements and the dma handle of the block within itself when freed. This means the smallest possible dmapool block is increased to at most 16 bytes to accommodate these fields, but there are no exisiting users requesting a dma pool smaller than that anyway. Removing the list has a significant change in performance. Using the kernel's micro-benchmarking self test: Before: # modprobe dmapool_test dmapool test: size:16 blocks:8192 time:57282 dmapool test: size:64 blocks:8192 time:172562 dmapool test: size:256 blocks:8192 time:789247 dmapool test: size:1024 blocks:2048 time:371823 dmapool test: size:4096 blocks:1024 time:362237 After: # modprobe dmapool_test dmapool test: size:16 blocks:8192 time:24997 dmapool test: size:64 blocks:8192 time:26584 dmapool test: size:256 blocks:8192 time:33542 dmapool test: size:1024 blocks:2048 time:9022 dmapool test: size:4096 blocks:1024 time:6045 The module test allocates quite a few blocks that may not accurately represent how these pools are used in real life. For a more marco level benchmark, running fio high-depth + high-batched on nvme, this patch shows submission and completion latency reduced by ~100usec each, 1% IOPs improvement, and perf record's time spent in dma_pool_alloc/free were reduced by half. [kbusch@kernel.org: push new blocks in ascending order] Link: https://lkml.kernel.org/r/20230221165400.1595247-1-kbusch@meta.com Link: https://lkml.kernel.org/r/20230126215125.4069751-12-kbusch@meta.com Fixes: 2d55c16c ("dmapool: create/destroy cleanup") Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Tony Battersby <tonyb@cybernetics.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Keith Busch authored
If debug is enabled, dmapool will poison the range, so no need to clear it to 0 immediately before writing over it. Link: https://lkml.kernel.org/r/20230126215125.4069751-11-kbusch@meta.com Fixes: 2d55c16c ("dmapool: create/destroy cleanup") Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Matthew Wilcox <willy@infradead.org> Cc: Tony Battersby <tonyb@cybernetics.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Keith Busch authored
The actions for busy and not busy are mostly the same, so combine these and remove the unnecessary function. Also, the pool is about to be freed so there's no need to poison the page data since we only check for poison on alloc, which can't be done on a freed pool. Link: https://lkml.kernel.org/r/20230126215125.4069751-10-kbusch@meta.com Fixes: 2d55c16c ("dmapool: create/destroy cleanup") Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Matthew Wilcox <willy@infradead.org> Cc: Tony Battersby <tonyb@cybernetics.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Keith Busch authored
Various fields of the dma pool are set in different places. Move it all to one function. Link: https://lkml.kernel.org/r/20230126215125.4069751-9-kbusch@meta.com Fixes: 2d55c16c ("dmapool: create/destroy cleanup") Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Matthew Wilcox <willy@infradead.org> Cc: Tony Battersby <tonyb@cybernetics.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Keith Busch authored
Handle the error in a condition so the good path can be in the normal flow. Link: https://lkml.kernel.org/r/20230126215125.4069751-8-kbusch@meta.com Fixes: 2d55c16c ("dmapool: create/destroy cleanup") Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Matthew Wilcox <willy@infradead.org> Cc: Tony Battersby <tonyb@cybernetics.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Keith Busch authored
Clean up the normal path by moving the debug code outside it. Link: https://lkml.kernel.org/r/20230126215125.4069751-7-kbusch@meta.com Fixes: 2d55c16c ("dmapool: create/destroy cleanup") Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Matthew Wilcox <willy@infradead.org> Cc: Tony Battersby <tonyb@cybernetics.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Tony Battersby authored
Avoid double-memset of the same allocated memory in dma_pool_alloc() when both DMAPOOL_DEBUG is enabled and init_on_alloc=1. Link: https://lkml.kernel.org/r/20230126215125.4069751-6-kbusch@meta.com Fixes: 2d55c16c ("dmapool: create/destroy cleanup") Signed-off-by: Tony Battersby <tonyb@cybernetics.com> Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Tony Battersby authored
To represent the size of a single allocation, dmapool currently uses 'unsigned int' in some places and 'size_t' in other places. Standardize on 'unsigned int' to reduce overhead, but use 'size_t' when counting all the blocks in the entire pool. Link: https://lkml.kernel.org/r/20230126215125.4069751-5-kbusch@meta.com Fixes: 2d55c16c ("dmapool: create/destroy cleanup") Signed-off-by: Tony Battersby <tonyb@cybernetics.com> Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Tony Battersby authored
Use sysfs_emit instead of scnprintf, snprintf or sprintf. Link: https://lkml.kernel.org/r/20230126215125.4069751-4-kbusch@meta.com Fixes: 2d55c16c ("dmapool: create/destroy cleanup") Signed-off-by: Tony Battersby <tonyb@cybernetics.com> Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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