diff options
author | Paolo Bonzini <pbonzini@redhat.com> | 2024-07-12 11:24:12 -0400 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2024-07-12 11:24:12 -0400 |
commit | c8b8b8190a80b591aa73c27c70a668799f8db547 (patch) | |
tree | 9d948c9aac89678abe64ac81f6c43348bf4b2091 /tools/perf | |
parent | f0a23883fad4ec8a63faddb9639a92be2e007624 (diff) | |
parent | 492ac37fa38faf520b5beae44c930063265ee183 (diff) |
Merge tag 'loongarch-kvm-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson into HEAD
LoongArch KVM changes for v6.11
1. Add ParaVirt steal time support.
2. Add some VM migration enhancement.
3. Add perf kvm-stat support for loongarch.
Diffstat (limited to 'tools/perf')
-rw-r--r-- | tools/perf/Makefile.perf | 1 | ||||
-rw-r--r-- | tools/perf/arch/loongarch/Makefile | 1 | ||||
-rw-r--r-- | tools/perf/arch/loongarch/util/Build | 2 | ||||
-rw-r--r-- | tools/perf/arch/loongarch/util/header.c | 96 | ||||
-rw-r--r-- | tools/perf/arch/loongarch/util/kvm-stat.c | 139 | ||||
-rw-r--r-- | tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl | 1 | ||||
-rw-r--r-- | tools/perf/arch/powerpc/entry/syscalls/syscall.tbl | 1 | ||||
-rw-r--r-- | tools/perf/arch/s390/entry/syscalls/syscall.tbl | 1 | ||||
-rw-r--r-- | tools/perf/arch/x86/entry/syscalls/syscall_64.tbl | 3 | ||||
-rw-r--r-- | tools/perf/builtin-record.c | 6 | ||||
-rw-r--r-- | tools/perf/builtin-trace.c | 2 | ||||
-rw-r--r-- | tools/perf/trace/beauty/arch/x86/include/asm/irq_vectors.h | 8 | ||||
-rw-r--r-- | tools/perf/trace/beauty/include/linux/socket.h | 3 | ||||
-rw-r--r-- | tools/perf/trace/beauty/include/uapi/linux/fcntl.h | 14 | ||||
-rw-r--r-- | tools/perf/trace/beauty/include/uapi/linux/prctl.h | 22 | ||||
-rw-r--r-- | tools/perf/trace/beauty/include/uapi/linux/stat.h | 4 |
16 files changed, 289 insertions, 15 deletions
diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf index 5c35c0d89306..e6d56b555369 100644 --- a/tools/perf/Makefile.perf +++ b/tools/perf/Makefile.perf @@ -214,6 +214,7 @@ NON_CONFIG_TARGETS := clean python-clean TAGS tags cscope help ifdef MAKECMDGOALS ifeq ($(filter-out $(NON_CONFIG_TARGETS),$(MAKECMDGOALS)),) + VMLINUX_H=$(src-perf)/util/bpf_skel/vmlinux/vmlinux.h config := 0 endif endif diff --git a/tools/perf/arch/loongarch/Makefile b/tools/perf/arch/loongarch/Makefile index 3992a67a87d9..c89d6bb6b184 100644 --- a/tools/perf/arch/loongarch/Makefile +++ b/tools/perf/arch/loongarch/Makefile @@ -4,6 +4,7 @@ PERF_HAVE_DWARF_REGS := 1 endif PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET := 1 PERF_HAVE_JITDUMP := 1 +HAVE_KVM_STAT_SUPPORT := 1 # # Syscall table generation for perf diff --git a/tools/perf/arch/loongarch/util/Build b/tools/perf/arch/loongarch/util/Build index d776125a2d06..b12d374d7096 100644 --- a/tools/perf/arch/loongarch/util/Build +++ b/tools/perf/arch/loongarch/util/Build @@ -1,5 +1,7 @@ +perf-y += header.o perf-y += perf_regs.o perf-$(CONFIG_DWARF) += dwarf-regs.o perf-$(CONFIG_LOCAL_LIBUNWIND) += unwind-libunwind.o perf-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o +perf-$(CONFIG_LIBTRACEEVENT) += kvm-stat.o diff --git a/tools/perf/arch/loongarch/util/header.c b/tools/perf/arch/loongarch/util/header.c new file mode 100644 index 000000000000..d962dff55512 --- /dev/null +++ b/tools/perf/arch/loongarch/util/header.c @@ -0,0 +1,96 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Implementation of get_cpuid(). + * + * Author: Nikita Shubin <n.shubin@yadro.com> + * Bibo Mao <maobibo@loongson.cn> + * Huacai Chen <chenhuacai@loongson.cn> + */ + +#include <stdio.h> +#include <stdlib.h> +#include <api/fs/fs.h> +#include <errno.h> +#include "util/debug.h" +#include "util/header.h" + +/* + * Output example from /proc/cpuinfo + * CPU Family : Loongson-64bit + * Model Name : Loongson-3C5000 + * CPU Revision : 0x10 + * FPU Revision : 0x01 + */ +#define CPUINFO_MODEL "Model Name" +#define CPUINFO "/proc/cpuinfo" + +static char *_get_field(const char *line) +{ + char *line2, *nl; + + line2 = strrchr(line, ' '); + if (!line2) + return NULL; + + line2++; + nl = strrchr(line, '\n'); + if (!nl) + return NULL; + + return strndup(line2, nl - line2); +} + +static char *_get_cpuid(void) +{ + unsigned long line_sz; + char *line, *model, *cpuid; + FILE *file; + + file = fopen(CPUINFO, "r"); + if (file == NULL) + return NULL; + + line = model = cpuid = NULL; + while (getline(&line, &line_sz, file) != -1) { + if (strncmp(line, CPUINFO_MODEL, strlen(CPUINFO_MODEL))) + continue; + + model = _get_field(line); + if (!model) + goto out_free; + break; + } + + if (model && (asprintf(&cpuid, "%s", model) < 0)) + cpuid = NULL; + +out_free: + fclose(file); + free(model); + return cpuid; +} + +int get_cpuid(char *buffer, size_t sz) +{ + int ret = 0; + char *cpuid = _get_cpuid(); + + if (!cpuid) + return EINVAL; + + if (sz < strlen(cpuid)) { + ret = ENOBUFS; + goto out_free; + } + + scnprintf(buffer, sz, "%s", cpuid); + +out_free: + free(cpuid); + return ret; +} + +char *get_cpuid_str(struct perf_pmu *pmu __maybe_unused) +{ + return _get_cpuid(); +} diff --git a/tools/perf/arch/loongarch/util/kvm-stat.c b/tools/perf/arch/loongarch/util/kvm-stat.c new file mode 100644 index 000000000000..a7859a3a9a51 --- /dev/null +++ b/tools/perf/arch/loongarch/util/kvm-stat.c @@ -0,0 +1,139 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <errno.h> +#include <memory.h> +#include "util/kvm-stat.h" +#include "util/parse-events.h" +#include "util/debug.h" +#include "util/evsel.h" +#include "util/evlist.h" +#include "util/pmus.h" + +#define LOONGARCH_EXCEPTION_INT 0 +#define LOONGARCH_EXCEPTION_PIL 1 +#define LOONGARCH_EXCEPTION_PIS 2 +#define LOONGARCH_EXCEPTION_PIF 3 +#define LOONGARCH_EXCEPTION_PME 4 +#define LOONGARCH_EXCEPTION_FPD 15 +#define LOONGARCH_EXCEPTION_SXD 16 +#define LOONGARCH_EXCEPTION_ASXD 17 +#define LOONGARCH_EXCEPTION_GSPR 22 +#define LOONGARCH_EXCEPTION_CPUCFG 100 +#define LOONGARCH_EXCEPTION_CSR 101 +#define LOONGARCH_EXCEPTION_IOCSR 102 +#define LOONGARCH_EXCEPTION_IDLE 103 +#define LOONGARCH_EXCEPTION_OTHERS 104 +#define LOONGARCH_EXCEPTION_HVC 23 + +#define loongarch_exception_type \ + {LOONGARCH_EXCEPTION_INT, "Interrupt" }, \ + {LOONGARCH_EXCEPTION_PIL, "Mem Read" }, \ + {LOONGARCH_EXCEPTION_PIS, "Mem Store" }, \ + {LOONGARCH_EXCEPTION_PIF, "Inst Fetch" }, \ + {LOONGARCH_EXCEPTION_PME, "Mem Modify" }, \ + {LOONGARCH_EXCEPTION_FPD, "FPU" }, \ + {LOONGARCH_EXCEPTION_SXD, "LSX" }, \ + {LOONGARCH_EXCEPTION_ASXD, "LASX" }, \ + {LOONGARCH_EXCEPTION_GSPR, "Privilege Error" }, \ + {LOONGARCH_EXCEPTION_HVC, "Hypercall" }, \ + {LOONGARCH_EXCEPTION_CPUCFG, "CPUCFG" }, \ + {LOONGARCH_EXCEPTION_CSR, "CSR" }, \ + {LOONGARCH_EXCEPTION_IOCSR, "IOCSR" }, \ + {LOONGARCH_EXCEPTION_IDLE, "Idle" }, \ + {LOONGARCH_EXCEPTION_OTHERS, "Others" } + +define_exit_reasons_table(loongarch_exit_reasons, loongarch_exception_type); + +const char *vcpu_id_str = "vcpu_id"; +const char *kvm_exit_reason = "reason"; +const char *kvm_entry_trace = "kvm:kvm_enter"; +const char *kvm_reenter_trace = "kvm:kvm_reenter"; +const char *kvm_exit_trace = "kvm:kvm_exit"; +const char *kvm_events_tp[] = { + "kvm:kvm_enter", + "kvm:kvm_reenter", + "kvm:kvm_exit", + "kvm:kvm_exit_gspr", + NULL, +}; + +static bool event_begin(struct evsel *evsel, + struct perf_sample *sample, struct event_key *key) +{ + return exit_event_begin(evsel, sample, key); +} + +static bool event_end(struct evsel *evsel, + struct perf_sample *sample __maybe_unused, + struct event_key *key __maybe_unused) +{ + /* + * LoongArch kvm is different with other architectures + * + * There is kvm:kvm_reenter or kvm:kvm_enter event adjacent with + * kvm:kvm_exit event. + * kvm:kvm_enter means returning to vmm and then to guest + * kvm:kvm_reenter means returning to guest immediately + */ + return evsel__name_is(evsel, kvm_entry_trace) || evsel__name_is(evsel, kvm_reenter_trace); +} + +static void event_gspr_get_key(struct evsel *evsel, + struct perf_sample *sample, struct event_key *key) +{ + unsigned int insn; + + key->key = LOONGARCH_EXCEPTION_OTHERS; + insn = evsel__intval(evsel, sample, "inst_word"); + + switch (insn >> 24) { + case 0: + /* CPUCFG inst trap */ + if ((insn >> 10) == 0x1b) + key->key = LOONGARCH_EXCEPTION_CPUCFG; + break; + case 4: + /* CSR inst trap */ + key->key = LOONGARCH_EXCEPTION_CSR; + break; + case 6: + /* IOCSR inst trap */ + if ((insn >> 15) == 0xc90) + key->key = LOONGARCH_EXCEPTION_IOCSR; + else if ((insn >> 15) == 0xc91) + /* Idle inst trap */ + key->key = LOONGARCH_EXCEPTION_IDLE; + break; + default: + key->key = LOONGARCH_EXCEPTION_OTHERS; + break; + } +} + +static struct child_event_ops child_events[] = { + { .name = "kvm:kvm_exit_gspr", .get_key = event_gspr_get_key }, + { NULL, NULL }, +}; + +static struct kvm_events_ops exit_events = { + .is_begin_event = event_begin, + .is_end_event = event_end, + .child_ops = child_events, + .decode_key = exit_event_decode_key, + .name = "VM-EXIT" +}; + +struct kvm_reg_events_ops kvm_reg_events_ops[] = { + { .name = "vmexit", .ops = &exit_events, }, + { NULL, NULL }, +}; + +const char * const kvm_skip_events[] = { + NULL, +}; + +int cpu_isa_init(struct perf_kvm_stat *kvm, const char *cpuid __maybe_unused) +{ + kvm->exit_reasons_isa = "loongarch64"; + kvm->exit_reasons = loongarch_exit_reasons; + return 0; +} diff --git a/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl b/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl index 532b855df589..1464c6be6eb3 100644 --- a/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl +++ b/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl @@ -376,3 +376,4 @@ 459 n64 lsm_get_self_attr sys_lsm_get_self_attr 460 n64 lsm_set_self_attr sys_lsm_set_self_attr 461 n64 lsm_list_modules sys_lsm_list_modules +462 n64 mseal sys_mseal diff --git a/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl b/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl index 17173b82ca21..3656f1ca7a21 100644 --- a/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl +++ b/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl @@ -548,3 +548,4 @@ 459 common lsm_get_self_attr sys_lsm_get_self_attr 460 common lsm_set_self_attr sys_lsm_set_self_attr 461 common lsm_list_modules sys_lsm_list_modules +462 common mseal sys_mseal diff --git a/tools/perf/arch/s390/entry/syscalls/syscall.tbl b/tools/perf/arch/s390/entry/syscalls/syscall.tbl index 095bb86339a7..bd0fee24ad10 100644 --- a/tools/perf/arch/s390/entry/syscalls/syscall.tbl +++ b/tools/perf/arch/s390/entry/syscalls/syscall.tbl @@ -464,3 +464,4 @@ 459 common lsm_get_self_attr sys_lsm_get_self_attr sys_lsm_get_self_attr 460 common lsm_set_self_attr sys_lsm_set_self_attr sys_lsm_set_self_attr 461 common lsm_list_modules sys_lsm_list_modules sys_lsm_list_modules +462 common mseal sys_mseal sys_mseal diff --git a/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl b/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl index 7e8d46f4147f..a396f6e6ab5b 100644 --- a/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl +++ b/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl @@ -374,7 +374,7 @@ 450 common set_mempolicy_home_node sys_set_mempolicy_home_node 451 common cachestat sys_cachestat 452 common fchmodat2 sys_fchmodat2 -453 64 map_shadow_stack sys_map_shadow_stack +453 common map_shadow_stack sys_map_shadow_stack 454 common futex_wake sys_futex_wake 455 common futex_wait sys_futex_wait 456 common futex_requeue sys_futex_requeue @@ -383,6 +383,7 @@ 459 common lsm_get_self_attr sys_lsm_get_self_attr 460 common lsm_set_self_attr sys_lsm_set_self_attr 461 common lsm_list_modules sys_lsm_list_modules +462 common mseal sys_mseal # # Due to a historical design error, certain syscalls are numbered differently diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 66a3de8ac661..0a8ba1323d64 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -1956,8 +1956,7 @@ static void record__read_lost_samples(struct record *rec) if (count.lost) { if (!lost) { - lost = zalloc(sizeof(*lost) + - session->machines.host.id_hdr_size); + lost = zalloc(PERF_SAMPLE_MAX_SIZE); if (!lost) { pr_debug("Memory allocation failed\n"); return; @@ -1973,8 +1972,7 @@ static void record__read_lost_samples(struct record *rec) lost_count = perf_bpf_filter__lost_count(evsel); if (lost_count) { if (!lost) { - lost = zalloc(sizeof(*lost) + - session->machines.host.id_hdr_size); + lost = zalloc(PERF_SAMPLE_MAX_SIZE); if (!lost) { pr_debug("Memory allocation failed\n"); return; diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index 51eca671c797..08a3a6effac1 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -765,7 +765,7 @@ static const char *fcntl_cmds[] = { static DEFINE_STRARRAY(fcntl_cmds, "F_"); static const char *fcntl_linux_specific_cmds[] = { - "SETLEASE", "GETLEASE", "NOTIFY", [5] = "CANCELLK", "DUPFD_CLOEXEC", + "SETLEASE", "GETLEASE", "NOTIFY", "DUPFD_QUERY", [5] = "CANCELLK", "DUPFD_CLOEXEC", "SETPIPE_SZ", "GETPIPE_SZ", "ADD_SEALS", "GET_SEALS", "GET_RW_HINT", "SET_RW_HINT", "GET_FILE_RW_HINT", "SET_FILE_RW_HINT", }; diff --git a/tools/perf/trace/beauty/arch/x86/include/asm/irq_vectors.h b/tools/perf/trace/beauty/arch/x86/include/asm/irq_vectors.h index d18bfb238f66..13aea8fc3d45 100644 --- a/tools/perf/trace/beauty/arch/x86/include/asm/irq_vectors.h +++ b/tools/perf/trace/beauty/arch/x86/include/asm/irq_vectors.h @@ -97,10 +97,16 @@ #define LOCAL_TIMER_VECTOR 0xec +/* + * Posted interrupt notification vector for all device MSIs delivered to + * the host kernel. + */ +#define POSTED_MSI_NOTIFICATION_VECTOR 0xeb + #define NR_VECTORS 256 #ifdef CONFIG_X86_LOCAL_APIC -#define FIRST_SYSTEM_VECTOR LOCAL_TIMER_VECTOR +#define FIRST_SYSTEM_VECTOR POSTED_MSI_NOTIFICATION_VECTOR #else #define FIRST_SYSTEM_VECTOR NR_VECTORS #endif diff --git a/tools/perf/trace/beauty/include/linux/socket.h b/tools/perf/trace/beauty/include/linux/socket.h index 139c330ccf2c..89d16b90370b 100644 --- a/tools/perf/trace/beauty/include/linux/socket.h +++ b/tools/perf/trace/beauty/include/linux/socket.h @@ -16,6 +16,7 @@ struct cred; struct socket; struct sock; struct sk_buff; +struct proto_accept_arg; #define __sockaddr_check_size(size) \ BUILD_BUG_ON(((size) > sizeof(struct __kernel_sockaddr_storage))) @@ -433,7 +434,7 @@ extern int __sys_recvfrom(int fd, void __user *ubuf, size_t size, extern int __sys_sendto(int fd, void __user *buff, size_t len, unsigned int flags, struct sockaddr __user *addr, int addr_len); -extern struct file *do_accept(struct file *file, unsigned file_flags, +extern struct file *do_accept(struct file *file, struct proto_accept_arg *arg, struct sockaddr __user *upeer_sockaddr, int __user *upeer_addrlen, int flags); extern int __sys_accept4(int fd, struct sockaddr __user *upeer_sockaddr, diff --git a/tools/perf/trace/beauty/include/uapi/linux/fcntl.h b/tools/perf/trace/beauty/include/uapi/linux/fcntl.h index 282e90aeb163..c0bcc185fa48 100644 --- a/tools/perf/trace/beauty/include/uapi/linux/fcntl.h +++ b/tools/perf/trace/beauty/include/uapi/linux/fcntl.h @@ -9,6 +9,14 @@ #define F_GETLEASE (F_LINUX_SPECIFIC_BASE + 1) /* + * Request nofications on a directory. + * See below for events that may be notified. + */ +#define F_NOTIFY (F_LINUX_SPECIFIC_BASE + 2) + +#define F_DUPFD_QUERY (F_LINUX_SPECIFIC_BASE + 3) + +/* * Cancel a blocking posix lock; internal use only until we expose an * asynchronous lock api to userspace: */ @@ -18,12 +26,6 @@ #define F_DUPFD_CLOEXEC (F_LINUX_SPECIFIC_BASE + 6) /* - * Request nofications on a directory. - * See below for events that may be notified. - */ -#define F_NOTIFY (F_LINUX_SPECIFIC_BASE+2) - -/* * Set and get of pipe page size array */ #define F_SETPIPE_SZ (F_LINUX_SPECIFIC_BASE + 7) diff --git a/tools/perf/trace/beauty/include/uapi/linux/prctl.h b/tools/perf/trace/beauty/include/uapi/linux/prctl.h index 370ed14b1ae0..35791791a879 100644 --- a/tools/perf/trace/beauty/include/uapi/linux/prctl.h +++ b/tools/perf/trace/beauty/include/uapi/linux/prctl.h @@ -306,4 +306,26 @@ struct prctl_mm_map { # define PR_RISCV_V_VSTATE_CTRL_NEXT_MASK 0xc # define PR_RISCV_V_VSTATE_CTRL_MASK 0x1f +#define PR_RISCV_SET_ICACHE_FLUSH_CTX 71 +# define PR_RISCV_CTX_SW_FENCEI_ON 0 +# define PR_RISCV_CTX_SW_FENCEI_OFF 1 +# define PR_RISCV_SCOPE_PER_PROCESS 0 +# define PR_RISCV_SCOPE_PER_THREAD 1 + +/* PowerPC Dynamic Execution Control Register (DEXCR) controls */ +#define PR_PPC_GET_DEXCR 72 +#define PR_PPC_SET_DEXCR 73 +/* DEXCR aspect to act on */ +# define PR_PPC_DEXCR_SBHE 0 /* Speculative branch hint enable */ +# define PR_PPC_DEXCR_IBRTPD 1 /* Indirect branch recurrent target prediction disable */ +# define PR_PPC_DEXCR_SRAPD 2 /* Subroutine return address prediction disable */ +# define PR_PPC_DEXCR_NPHIE 3 /* Non-privileged hash instruction enable */ +/* Action to apply / return */ +# define PR_PPC_DEXCR_CTRL_EDITABLE 0x1 /* Aspect can be modified with PR_PPC_SET_DEXCR */ +# define PR_PPC_DEXCR_CTRL_SET 0x2 /* Set the aspect for this process */ +# define PR_PPC_DEXCR_CTRL_CLEAR 0x4 /* Clear the aspect for this process */ +# define PR_PPC_DEXCR_CTRL_SET_ONEXEC 0x8 /* Set the aspect on exec */ +# define PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC 0x10 /* Clear the aspect on exec */ +# define PR_PPC_DEXCR_CTRL_MASK 0x1f + #endif /* _LINUX_PRCTL_H */ diff --git a/tools/perf/trace/beauty/include/uapi/linux/stat.h b/tools/perf/trace/beauty/include/uapi/linux/stat.h index 2f2ee82d5517..67626d535316 100644 --- a/tools/perf/trace/beauty/include/uapi/linux/stat.h +++ b/tools/perf/trace/beauty/include/uapi/linux/stat.h @@ -126,8 +126,9 @@ struct statx { __u64 stx_mnt_id; __u32 stx_dio_mem_align; /* Memory buffer alignment for direct I/O */ __u32 stx_dio_offset_align; /* File offset alignment for direct I/O */ + __u64 stx_subvol; /* Subvolume identifier */ /* 0xa0 */ - __u64 __spare3[12]; /* Spare space for future expansion */ + __u64 __spare3[11]; /* Spare space for future expansion */ /* 0x100 */ }; @@ -155,6 +156,7 @@ struct statx { #define STATX_MNT_ID 0x00001000U /* Got stx_mnt_id */ #define STATX_DIOALIGN 0x00002000U /* Want/got direct I/O alignment info */ #define STATX_MNT_ID_UNIQUE 0x00004000U /* Want/got extended stx_mount_id */ +#define STATX_SUBVOL 0x00008000U /* Want/got stx_subvol */ #define STATX__RESERVED 0x80000000U /* Reserved for future struct statx expansion */ |