From: Pu Lehui Date: Sat, 31 Aug 2024 04:19:31 +0000 (+0000) Subject: libbpf: Access first syscall argument with CO-RE direct read on s390 X-Git-Tag: v6.12-rc1~112^2~42^2~3 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=e4db2a821b6cff4bd59c0efabdbfdd84ac6005c1;p=thirdparty%2Fkernel%2Flinux.git libbpf: Access first syscall argument with CO-RE direct read on s390 Currently PT_REGS_PARM1 SYSCALL(x) is consistent with PT_REGS_PARM1_CORE SYSCALL(x), which will introduce the overhead of BPF_CORE_READ(), taking into account the read pt_regs comes directly from the context, let's use CO-RE direct read to access the first system call argument. Suggested-by: Andrii Nakryiko Signed-off-by: Pu Lehui Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20240831041934.1629216-2-pulehui@huaweicloud.com --- diff --git a/tools/lib/bpf/bpf_tracing.h b/tools/lib/bpf/bpf_tracing.h index 9314fa95f04e8..1297d8d297d17 100644 --- a/tools/lib/bpf/bpf_tracing.h +++ b/tools/lib/bpf/bpf_tracing.h @@ -163,7 +163,7 @@ struct pt_regs___s390 { unsigned long orig_gpr2; -}; +} __attribute__((preserve_access_index)); /* s390 provides user_pt_regs instead of struct pt_regs to userspace */ #define __PT_REGS_CAST(x) ((const user_pt_regs *)(x)) @@ -179,7 +179,7 @@ struct pt_regs___s390 { #define __PT_PARM4_SYSCALL_REG __PT_PARM4_REG #define __PT_PARM5_SYSCALL_REG __PT_PARM5_REG #define __PT_PARM6_SYSCALL_REG gprs[7] -#define PT_REGS_PARM1_SYSCALL(x) PT_REGS_PARM1_CORE_SYSCALL(x) +#define PT_REGS_PARM1_SYSCALL(x) (((const struct pt_regs___s390 *)(x))->__PT_PARM1_SYSCALL_REG) #define PT_REGS_PARM1_CORE_SYSCALL(x) \ BPF_CORE_READ((const struct pt_regs___s390 *)(x), __PT_PARM1_SYSCALL_REG)