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riscv: kselftests: Fix mm build by removing testcases subdirectory #32
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kselftests fails to build because the mm/testcases subdirectory is not created and then the compiler fails to output the binary there. So fix this by simply removing this subdirectory which is not very useful. Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>
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At least one diff in series https://patchwork.kernel.org/project/linux-riscv/list/?series=784534 irrelevant now. Closing PR. |
When I use older version aarch64 objdump (2.24) to disassemble aarch64 vmlinux, I get the result like below. There is no space between sp and offset. ffff800008010000 <dw_apb_ictl_handle_irq>: ffff800008010000: d503233f hint #0x19 ffff800008010004: a9bc7bfd stp x29, x30, [sp,#-64]! ffff800008010008: 90011e60 adrp x0, ffff80000a3dc000 <num_ictlrs> ffff80000801000c: 910003fd mov x29, sp ffff800008010010: a9025bf5 stp x21, x22, [sp,#32] When I use newer version aarch64 objdump (2.35), I get the result like below. There is a space between sp and offset. ffff800008010000 <dw_apb_ictl_handle_irq>: ffff800008010000: d503233f paciasp ffff800008010004: a9bc7bfd stp x29, x30, [sp, #-64]! ffff800008010008: 90011e60 adrp x0, ffff80000a3dc000 <num_ictlrs> ffff80000801000c: 910003fd mov x29, sp ffff800008010010: a9025bf5 stp x21, x22, [sp, #32] Add no space support of regular expression for old version objdump. Link: https://lkml.kernel.org/r/20231220073629.2658-1-Kuan-Ying.Lee@mediatek.com Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com> Cc: Casper Li <casper.li@mediatek.com> Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Cc: Chinwen Chang <chinwen.chang@mediatek.com> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: Qun-Wei Lin <qun-wei.lin@mediatek.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If an abnormally huge cnt is used for multi-uprobes attachment, the following warning will be reported: ------------[ cut here ]------------ WARNING: CPU: 7 PID: 406 at mm/util.c:632 kvmalloc_node+0xd9/0xe0 Modules linked in: bpf_testmod(O) CPU: 7 PID: 406 Comm: test_progs Tainted: G ...... 6.7.0-rc3+ #32 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ...... RIP: 0010:kvmalloc_node+0xd9/0xe0 ...... Call Trace: <TASK> ? __warn+0x89/0x150 ? kvmalloc_node+0xd9/0xe0 bpf_uprobe_multi_link_attach+0x14a/0x480 __sys_bpf+0x14a9/0x2bc0 do_syscall_64+0x36/0xb0 entry_SYSCALL_64_after_hwframe+0x6e/0x76 ...... </TASK> ---[ end trace 0000000000000000 ]--- So add a test to ensure the warning is fixed. Signed-off-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20231215100708.2265609-4-houtao@huaweicloud.com
If an abnormally huge cnt is used for multi-kprobes attachment, the following warning will be reported: ------------[ cut here ]------------ WARNING: CPU: 1 PID: 392 at mm/util.c:632 kvmalloc_node+0xd9/0xe0 Modules linked in: bpf_testmod(O) CPU: 1 PID: 392 Comm: test_progs Tainted: G ...... 6.7.0-rc3+ #32 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ...... RIP: 0010:kvmalloc_node+0xd9/0xe0 ? __warn+0x89/0x150 ? kvmalloc_node+0xd9/0xe0 bpf_kprobe_multi_link_attach+0x87/0x670 __sys_bpf+0x2a28/0x2bc0 __x64_sys_bpf+0x1a/0x30 do_syscall_64+0x36/0xb0 entry_SYSCALL_64_after_hwframe+0x6e/0x76 RIP: 0033:0x7fbe067f0e0d ...... </TASK> ---[ end trace 0000000000000000 ]--- So add a test to ensure the warning is fixed. Signed-off-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20231215100708.2265609-6-houtao@huaweicloud.com
------------[ cut here ]------------ memcpy: detected field-spanning write (size 56) of single field "eseg->inline_hdr.start" at /var/lib/dkms/mlnx-ofed-kernel/5.8/build/drivers/infiniband/hw/mlx5/wr.c:131 (size 2) WARNING: CPU: 0 PID: 293779 at /var/lib/dkms/mlnx-ofed-kernel/5.8/build/drivers/infiniband/hw/mlx5/wr.c:131 mlx5_ib_post_send+0x191b/0x1a60 [mlx5_ib] Modules linked in: 8021q garp mrp stp llc rdma_ucm(OE) rdma_cm(OE) iw_cm(OE) ib_ipoib(OE) ib_cm(OE) ib_umad(OE) mlx5_ib(OE) ib_uverbs(OE) ib_core(OE) mlx5_core(OE) pci_hyperv_intf mlxdevm(OE) mlx_compat(OE) tls mlxfw(OE) psample nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables libcrc32c nfnetlink mst_pciconf(OE) knem(OE) vfio_pci vfio_pci_core vfio_iommu_type1 vfio iommufd irqbypass cuse nfsv3 nfs fscache netfs xfrm_user xfrm_algo ipmi_devintf ipmi_msghandler binfmt_misc crct10dif_pclmul crc32_pclmul polyval_clmulni polyval_generic ghash_clmulni_intel sha512_ssse3 snd_pcsp aesni_intel crypto_simd cryptd snd_pcm snd_timer joydev snd soundcore input_leds serio_raw evbug nfsd auth_rpcgss nfs_acl lockd grace sch_fq_codel sunrpc drm efi_pstore ip_tables x_tables autofs4 psmouse virtio_net net_failover failover floppy [last unloaded: mlx_compat(OE)] CPU: 0 PID: 293779 Comm: ssh Tainted: G OE 6.2.0-32-generic #32~22.04.1-Ubuntu Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 RIP: 0010:mlx5_ib_post_send+0x191b/0x1a60 [mlx5_ib] Code: 0c 01 00 a8 01 75 25 48 8b 75 a0 b9 02 00 00 00 48 c7 c2 10 5b fd c0 48 c7 c7 80 5b fd c0 c6 05 57 0c 03 00 01 e8 95 4d 93 da <0f> 0b 44 8b 4d b0 4c 8b 45 c8 48 8b 4d c0 e9 49 fb ff ff 41 0f b7 RSP: 0018:ffffb5b48478b570 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffb5b48478b628 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffb5b48478b5e8 R13: ffff963a3c609b5e R14: ffff9639c3fbd800 R15: ffffb5b480475a80 FS: 00007fc03b444c80(0000) GS:ffff963a3dc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000556f46bdf000 CR3: 0000000006ac6003 CR4: 00000000003706f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ? show_regs+0x72/0x90 ? mlx5_ib_post_send+0x191b/0x1a60 [mlx5_ib] ? __warn+0x8d/0x160 ? mlx5_ib_post_send+0x191b/0x1a60 [mlx5_ib] ? report_bug+0x1bb/0x1d0 ? handle_bug+0x46/0x90 ? exc_invalid_op+0x19/0x80 ? asm_exc_invalid_op+0x1b/0x20 ? mlx5_ib_post_send+0x191b/0x1a60 [mlx5_ib] mlx5_ib_post_send_nodrain+0xb/0x20 [mlx5_ib] ipoib_send+0x2ec/0x770 [ib_ipoib] ipoib_start_xmit+0x5a0/0x770 [ib_ipoib] dev_hard_start_xmit+0x8e/0x1e0 ? validate_xmit_skb_list+0x4d/0x80 sch_direct_xmit+0x116/0x3a0 __dev_xmit_skb+0x1fd/0x580 __dev_queue_xmit+0x284/0x6b0 ? _raw_spin_unlock_irq+0xe/0x50 ? __flush_work.isra.0+0x20d/0x370 ? push_pseudo_header+0x17/0x40 [ib_ipoib] neigh_connected_output+0xcd/0x110 ip_finish_output2+0x179/0x480 ? __smp_call_single_queue+0x61/0xa0 __ip_finish_output+0xc3/0x190 ip_finish_output+0x2e/0xf0 ip_output+0x78/0x110 ? __pfx_ip_finish_output+0x10/0x10 ip_local_out+0x64/0x70 __ip_queue_xmit+0x18a/0x460 ip_queue_xmit+0x15/0x30 __tcp_transmit_skb+0x914/0x9c0 tcp_write_xmit+0x334/0x8d0 tcp_push_one+0x3c/0x60 tcp_sendmsg_locked+0x2e1/0xac0 tcp_sendmsg+0x2d/0x50 inet_sendmsg+0x43/0x90 sock_sendmsg+0x68/0x80 sock_write_iter+0x93/0x100 vfs_write+0x326/0x3c0 ksys_write+0xbd/0xf0 ? do_syscall_64+0x69/0x90 __x64_sys_write+0x19/0x30 do_syscall_64+0x59/0x90 ? do_user_addr_fault+0x1d0/0x640 ? exit_to_user_mode_prepare+0x3b/0xd0 ? irqentry_exit_to_user_mode+0x9/0x20 ? irqentry_exit+0x43/0x50 ? exc_page_fault+0x92/0x1b0 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7fc03ad14a37 Code: 10 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24 RSP: 002b:00007ffdf8697fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000008024 RCX: 00007fc03ad14a37 RDX: 0000000000008024 RSI: 0000556f46bd8270 RDI: 0000000000000003 RBP: 0000556f46bb1800 R08: 0000000000007fe3 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 R13: 0000556f46bc66b0 R14: 000000000000000a R15: 0000556f46bb2f50 </TASK> ---[ end trace 0000000000000000 ]--- Link: https://lore.kernel.org/r/8228ad34bd1a25047586270f7b1fb4ddcd046282.1706433934.git.leon@kernel.org Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Currently our IO accessors all use register addressing without offsets, but we could safely use offset addressing (without writeback) to simplify and optimize the generated code. To function correctly under a hypervisor which emulates IO accesses, we must ensure that any faulting/trapped IO access results in an ESR_ELx value with ESR_ELX.ISS.ISV=1 and with the tranfer register described in ESR_ELx.ISS.SRT. This means that we can only use loads/stores of a single general purpose register (or the zero register), and must avoid writeback addressing modes. However, we can use immediate offset addressing modes, as these still provide ESR_ELX.ISS.ISV=1 and a valid ESR_ELx.ISS.SRT when those accesses fault at Stage-2. Currently we only use register addressing without offsets. We use the "r" constraint to place the address into a register, and manually generate the register addressing by surrounding the resulting register operand with square braces, e.g. | static __always_inline void __raw_writeq(u64 val, volatile void __iomem *addr) | { | asm volatile("str %x0, [%1]" : : "rZ" (val), "r" (addr)); | } Due to this, sequences of adjacent accesses need to generate addresses using separate instructions. For example, the following code: | void writeq_zero_8_times(void *ptr) | { | writeq_relaxed(0, ptr + 8 * 0); | writeq_relaxed(0, ptr + 8 * 1); | writeq_relaxed(0, ptr + 8 * 2); | writeq_relaxed(0, ptr + 8 * 3); | writeq_relaxed(0, ptr + 8 * 4); | writeq_relaxed(0, ptr + 8 * 5); | writeq_relaxed(0, ptr + 8 * 6); | writeq_relaxed(0, ptr + 8 * 7); | } ... is compiled to: | <writeq_zero_8_times>: | str xzr, [x0] | add x1, x0, #0x8 | str xzr, [x1] | add x1, x0, #0x10 | str xzr, [x1] | add x1, x0, #0x18 | str xzr, [x1] | add x1, x0, #0x20 | str xzr, [x1] | add x1, x0, #0x28 | str xzr, [x1] | add x1, x0, #0x30 | str xzr, [x1] | add x0, x0, #0x38 | str xzr, [x0] | ret As described above, we could safely use immediate offset addressing, which would allow the ADDs to be folded into the address generation for the STRs, resulting in simpler and smaller generated assembly. We can do this by using the "o" constraint to allow the compiler to generate offset addressing (without writeback) for a memory operand, e.g. | static __always_inline void __raw_writeq(u64 val, volatile void __iomem *addr) | { | volatile u64 __iomem *ptr = addr; | asm volatile("str %x0, %1" : : "rZ" (val), "o" (*ptr)); | } ... which results in the earlier code sequence being compiled to: | <writeq_zero_8_times>: | str xzr, [x0] | str xzr, [x0, #8] | str xzr, [x0, #16] | str xzr, [x0, #24] | str xzr, [x0, #32] | str xzr, [x0, #40] | str xzr, [x0, #48] | str xzr, [x0, #56] | ret As Will notes at: https://lore.kernel.org/linux-arm-kernel/20240117160528.GA3398@willie-the-truck/ ... some compilers struggle with a plain "o" constraint, so it's preferable to use "Qo", where the additional "Q" constraint permits using non-offset register addressing. This patch modifies our IO write accessors to use "Qo" constraints, resulting in the better code generation described above. The IO read accessors are left as-is because ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE requires that non-offset register addressing is used, as the LDAR instruction does not support offset addressing. When compiling v6.8-rc1 defconfig with GCC 13.2.0, this saves ~4KiB of text: | [mark@lakrids:~/src/linux]% ls -al vmlinux-* | -rwxr-xr-x 1 mark mark 153960576 Jan 23 12:01 vmlinux-after | -rwxr-xr-x 1 mark mark 153862192 Jan 23 11:57 vmlinux-before | | [mark@lakrids:~/src/linux]% size vmlinux-before vmlinux-after | text data bss dec hex filename | 26708921 16690350 622736 44022007 29fb8f7 vmlinux-before | 26704761 16690414 622736 44017911 29fa8f7 vmlinux-after ... though due to internal alignment of sections, this has no impact on the size of the resulting Image: | [mark@lakrids:~/src/linux]% ls -al Image-* | -rw-r--r-- 1 mark mark 43590144 Jan 23 12:01 Image-after | -rw-r--r-- 1 mark mark 43590144 Jan 23 11:57 Image-before Aside from the better code generation, there should be no functional change as a result of this patch. I have lightly tested this patch, including booting under KVM (where some devices such as PL011 are emulated). Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Will Deacon <will@kernel.org> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20240124111259.874975-1-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
With BPF_PROBE_MEM, BPF allows de-referencing an untrusted pointer. To thwart invalid memory accesses, the JITs add an exception table entry for all such accesses. But in case the src_reg + offset is a userspace address, the BPF program might read that memory if the user has mapped it. Make the verifier add guard instructions around such memory accesses and skip the load if the address falls into the userspace region. The JITs need to implement bpf_arch_uaddress_limit() to define where the userspace addresses end for that architecture or TASK_SIZE is taken as default. The implementation is as follows: REG_AX = SRC_REG if(offset) REG_AX += offset; REG_AX >>= 32; if (REG_AX <= (uaddress_limit >> 32)) DST_REG = 0; else DST_REG = *(size *)(SRC_REG + offset); Comparing just the upper 32 bits of the load address with the upper 32 bits of uaddress_limit implies that the values are being aligned down to a 4GB boundary before comparison. The above means that all loads with address <= uaddress_limit + 4GB are skipped. This is acceptable because there is a large hole (much larger than 4GB) between userspace and kernel space memory, therefore a correctly functioning BPF program should not access this 4GB memory above the userspace. Let's analyze what this patch does to the following fentry program dereferencing an untrusted pointer: SEC("fentry/tcp_v4_connect") int BPF_PROG(fentry_tcp_v4_connect, struct sock *sk) { *(volatile long *)sk; return 0; } BPF Program before | BPF Program after ------------------ | ----------------- 0: (79) r1 = *(u64 *)(r1 +0) 0: (79) r1 = *(u64 *)(r1 +0) ----------------------------------------------------------------------- 1: (79) r1 = *(u64 *)(r1 +0) --\ 1: (bf) r11 = r1 ----------------------------\ \ 2: (77) r11 >>= 32 2: (b7) r0 = 0 \ \ 3: (b5) if r11 <= 0x8000 goto pc+2 3: (95) exit \ \-> 4: (79) r1 = *(u64 *)(r1 +0) \ 5: (05) goto pc+1 \ 6: (b7) r1 = 0 \-------------------------------------- 7: (b7) r0 = 0 8: (95) exit As you can see from above, in the best case (off=0), 5 extra instructions are emitted. Now, we analyze the same program after it has gone through the JITs of ARM64 and RISC-V architectures. We follow the single load instruction that has the untrusted pointer and see what instrumentation has been added around it. x86-64 JIT ========== JIT's Instrumentation (upstream) --------------------- 0: nopl 0x0(%rax,%rax,1) 5: xchg %ax,%ax 7: push %rbp 8: mov %rsp,%rbp b: mov 0x0(%rdi),%rdi --------------------------------- f: movabs $0x800000000000,%r11 19: cmp %r11,%rdi 1c: jb 0x000000000000002a 1e: mov %rdi,%r11 21: add $0x0,%r11 28: jae 0x000000000000002e 2a: xor %edi,%edi 2c: jmp 0x0000000000000032 2e: mov 0x0(%rdi),%rdi --------------------------------- 32: xor %eax,%eax 34: leave 35: ret The x86-64 JIT already emits some instructions to protect against user memory access. This patch doesn't make any changes for the x86-64 JIT. ARM64 JIT ========= No Intrumentation Verifier's Instrumentation (upstream) (This patch) ----------------- -------------------------- 0: add x9, x30, #0x0 0: add x9, x30, #0x0 4: nop 4: nop 8: paciasp 8: paciasp c: stp x29, x30, [sp, #-16]! c: stp x29, x30, [sp, #-16]! 10: mov x29, sp 10: mov x29, sp 14: stp x19, x20, [sp, #-16]! 14: stp x19, x20, [sp, #-16]! 18: stp x21, x22, [sp, #-16]! 18: stp x21, x22, [sp, #-16]! 1c: stp x25, x26, [sp, #-16]! 1c: stp x25, x26, [sp, #-16]! 20: stp x27, x28, [sp, #-16]! 20: stp x27, x28, [sp, #-16]! 24: mov x25, sp 24: mov x25, sp 28: mov x26, #0x0 28: mov x26, #0x0 2c: sub x27, x25, #0x0 2c: sub x27, x25, #0x0 30: sub sp, sp, #0x0 30: sub sp, sp, #0x0 34: ldr x0, [x0] 34: ldr x0, [x0] -------------------------------------------------------------------------------- 38: ldr x0, [x0] ----------\ 38: add x9, x0, #0x0 -----------------------------------\\ 3c: lsr x9, x9, #32 3c: mov x7, #0x0 \\ 40: cmp x9, #0x10, lsl #12 40: mov sp, sp \\ 44: b.ls 0x0000000000000050 44: ldp x27, x28, [sp], #16 \\--> 48: ldr x0, [x0] 48: ldp x25, x26, [sp], #16 \ 4c: b 0x0000000000000054 4c: ldp x21, x22, [sp], #16 \ 50: mov x0, #0x0 50: ldp x19, x20, [sp], #16 \--------------------------------------- 54: ldp x29, x30, [sp], #16 54: mov x7, #0x0 58: add x0, x7, #0x0 58: mov sp, sp 5c: autiasp 5c: ldp x27, x28, [sp], #16 60: ret 60: ldp x25, x26, [sp], #16 64: nop 64: ldp x21, x22, [sp], #16 68: ldr x10, 0x0000000000000070 68: ldp x19, x20, [sp], #16 6c: br x10 6c: ldp x29, x30, [sp], #16 70: add x0, x7, #0x0 74: autiasp 78: ret 7c: nop 80: ldr x10, 0x0000000000000088 84: br x10 There are 6 extra instructions added in ARM64 in the best case. This will become 7 in the worst case (off != 0). RISC-V JIT (RISCV_ISA_C Disabled) ========== No Intrumentation Verifier's Instrumentation (upstream) (This patch) ----------------- -------------------------- 0: nop 0: nop 4: nop 4: nop 8: li a6, 33 8: li a6, 33 c: addi sp, sp, -16 c: addi sp, sp, -16 10: sd s0, 8(sp) 10: sd s0, 8(sp) 14: addi s0, sp, 16 14: addi s0, sp, 16 18: ld a0, 0(a0) 18: ld a0, 0(a0) --------------------------------------------------------------- 1c: ld a0, 0(a0) --\ 1c: mv t0, a0 --------------------------\ \ 20: srli t0, t0, 32 20: li a5, 0 \ \ 24: lui t1, 4096 24: ld s0, 8(sp) \ \ 28: sext.w t1, t1 28: addi sp, sp, 16 \ \ 2c: bgeu t1, t0, 12 2c: sext.w a0, a5 \ \--> 30: ld a0, 0(a0) 30: ret \ 34: j 8 \ 38: li a0, 0 \------------------------------ 3c: li a5, 0 40: ld s0, 8(sp) 44: addi sp, sp, 16 48: sext.w a0, a5 4c: ret There are 7 extra instructions added in RISC-V. Fixes: 8008342 ("bpf, arm64: Add BPF exception tables") Reported-by: Breno Leitao <leitao@debian.org> Suggested-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Puranjay Mohan <puranjay12@gmail.com> Link: https://lore.kernel.org/r/20240424100210.11982-2-puranjay@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Inline calls to bpf_get_smp_processor_id() helper in the JIT by emitting a read from struct thread_info. The SP_EL0 system register holds the pointer to the task_struct and thread_info is the first member of this struct. We can read the cpu number from the thread_info. Here is how the ARM64 JITed assembly changes after this commit: ARM64 JIT =========== BEFORE AFTER -------- ------- int cpu = bpf_get_smp_processor_id(); int cpu = bpf_get_smp_processor_id(); mov x10, #0xfffffffffffff4d0 mrs x10, sp_el0 movk x10, #0x802b, lsl #16 ldr w7, [x10, #24] movk x10, #0x8000, lsl #32 blr x10 add x7, x0, #0x0 Performance improvement using benchmark[1] ./benchs/run_bench_trigger.sh glob-arr-inc arr-inc hash-inc +---------------+-------------------+-------------------+--------------+ | Name | Before | After | % change | |---------------+-------------------+-------------------+--------------| | glob-arr-inc | 23.380 ± 1.675M/s | 25.893 ± 0.026M/s | + 10.74% | | arr-inc | 23.928 ± 0.034M/s | 25.213 ± 0.063M/s | + 5.37% | | hash-inc | 12.352 ± 0.005M/s | 12.609 ± 0.013M/s | + 2.08% | +---------------+-------------------+-------------------+--------------+ [1] anakryiko@8dec900975ef Signed-off-by: Puranjay Mohan <puranjay@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240502151854.9810-5-puranjay@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Puranjay Mohan says: ==================== bpf: Inline helpers in arm64 and riscv JITs Changes in v5 -> v6: arm64 v5: https://lore.kernel.org/all/20240430234739.79185-1-puranjay@kernel.org/ riscv v2: https://lore.kernel.org/all/20240430175834.33152-1-puranjay@kernel.org/ - Combine riscv and arm64 changes in single series - Some coding style fixes Changes in v4 -> v5: v4: https://lore.kernel.org/all/20240429131647.50165-1-puranjay@kernel.org/ - Implement the inlining of the bpf_get_smp_processor_id() in the JIT. NOTE: This needs to be based on: https://lore.kernel.org/all/20240430175834.33152-1-puranjay@kernel.org/ to be built. Manual run of bpf-ci with this series rebased on above: kernel-patches/bpf#6929 Changes in v3 -> v4: v3: https://lore.kernel.org/all/20240426121349.97651-1-puranjay@kernel.org/ - Fix coding style issue related to C89 standards. Changes in v2 -> v3: v2: https://lore.kernel.org/all/20240424173550.16359-1-puranjay@kernel.org/ - Fixed the xlated dump of percpu mov to "r0 = &(void __percpu *)(r0)" - Made ARM64 and x86-64 use the same code for inlining. The only difference that remains is the per-cpu address of the cpu_number. Changes in v1 -> v2: v1: https://lore.kernel.org/all/20240405091707.66675-1-puranjay12@gmail.com/ - Add a patch to inline bpf_get_smp_processor_id() - Fix an issue in MRS instruction encoding as pointed out by Will - Remove CONFIG_SMP check because arm64 kernel always compiles with CONFIG_SMP This series adds the support of internal only per-CPU instructions and inlines the bpf_get_smp_processor_id() helper call for ARM64 and RISC-V BPF JITs. Here is an example of calls to bpf_get_smp_processor_id() and percpu_array_map_lookup_elem() before and after this series on ARM64. BPF ===== BEFORE AFTER -------- ------- int cpu = bpf_get_smp_processor_id(); int cpu = bpf_get_smp_processor_id(); (85) call bpf_get_smp_processor_id#229032 (85) call bpf_get_smp_processor_id#8 p = bpf_map_lookup_elem(map, &zero); p = bpf_map_lookup_elem(map, &zero); (18) r1 = map[id:78] (18) r1 = map[id:153] (18) r2 = map[id:82][0]+65536 (18) r2 = map[id:157][0]+65536 (85) call percpu_array_map_lookup_elem#313512 (07) r1 += 496 (61) r0 = *(u32 *)(r2 +0) (35) if r0 >= 0x1 goto pc+5 (67) r0 <<= 3 (0f) r0 += r1 (79) r0 = *(u64 *)(r0 +0) (bf) r0 = &(void __percpu *)(r0) (05) goto pc+1 (b7) r0 = 0 ARM64 JIT =========== BEFORE AFTER -------- ------- int cpu = bpf_get_smp_processor_id(); int cpu = bpf_get_smp_processor_id(); mov x10, #0xfffffffffffff4d0 mrs x10, sp_el0 movk x10, #0x802b, lsl #16 ldr w7, [x10, #24] movk x10, #0x8000, lsl #32 blr x10 add x7, x0, #0x0 p = bpf_map_lookup_elem(map, &zero); p = bpf_map_lookup_elem(map, &zero); mov x0, #0xffff0003ffffffff mov x0, #0xffff0003ffffffff movk x0, #0xce5c, lsl #16 movk x0, #0xe0f3, lsl #16 movk x0, #0xca00 movk x0, #0x7c00 mov x1, #0xffff8000ffffffff mov x1, #0xffff8000ffffffff movk x1, #0x8bdb, lsl #16 movk x1, #0xb0c7, lsl #16 movk x1, #0x6000 movk x1, #0xe000 mov x10, #0xffffffffffff3ed0 add x0, x0, #0x1f0 movk x10, #0x802d, lsl #16 ldr w7, [x1] movk x10, #0x8000, lsl #32 cmp x7, #0x1 blr x10 b.cs 0x0000000000000090 add x7, x0, #0x0 lsl x7, x7, #3 add x7, x7, x0 ldr x7, [x7] mrs x10, tpidr_el1 add x7, x7, x10 b 0x0000000000000094 mov x7, #0x0 Performance improvement found using benchmark[1] ./benchs/run_bench_trigger.sh glob-arr-inc arr-inc hash-inc +---------------+-------------------+-------------------+--------------+ | Name | Before | After | % change | |---------------+-------------------+-------------------+--------------| | glob-arr-inc | 23.380 ± 1.675M/s | 25.893 ± 0.026M/s | + 10.74% | | arr-inc | 23.928 ± 0.034M/s | 25.213 ± 0.063M/s | + 5.37% | | hash-inc | 12.352 ± 0.005M/s | 12.609 ± 0.013M/s | + 2.08% | +---------------+-------------------+-------------------+--------------+ [1] anakryiko@8dec900975ef RISCV64 JIT output for `call bpf_get_smp_processor_id` ======================================================= Before After -------- ------- auipc t1,0x848c ld a5,32(tp) jalr 604(t1) mv a5,a0 Benchmark using [1] on Qemu. ./benchs/run_bench_trigger.sh glob-arr-inc arr-inc hash-inc +---------------+------------------+------------------+--------------+ | Name | Before | After | % change | |---------------+------------------+------------------+--------------| | glob-arr-inc | 1.077 ± 0.006M/s | 1.336 ± 0.010M/s | + 24.04% | | arr-inc | 1.078 ± 0.002M/s | 1.332 ± 0.015M/s | + 23.56% | | hash-inc | 0.494 ± 0.004M/s | 0.653 ± 0.001M/s | + 32.18% | +---------------+------------------+------------------+--------------+ ==================== Link: https://lore.kernel.org/r/20240502151854.9810-1-puranjay@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Pull request for series with
subject: riscv: kselftests: Fix mm build by removing testcases subdirectory
version: 1
url: https://patchwork.kernel.org/project/linux-riscv/list/?series=784534