When epoll_wait returns, extract the content of the "events" field (events set and data payload).
Here is an example output: syscall_entry_epoll_wait: { epfd = 3, maxevents = 32, timeout = 100 } syscall_exit_epoll_wait: { ret = 1, fds_length = 1, fds = [ [0] = { raw_events = 0x1, events = { EPOLLIN = 1, EPOLLPRI = 0, EPOLLOUT = 0, EPOLLERR = 0, padding = 0 }, data_union = { u64 = 0x100000005, fd = 5 } } ] } Signed-off-by: Julien Desfossez <jdesfos...@efficios.com> --- .../syscalls/headers/syscalls_pointers_override.h | 234 +++++++++++++++++++++ 1 file changed, 234 insertions(+) diff --git a/instrumentation/syscalls/headers/syscalls_pointers_override.h b/instrumentation/syscalls/headers/syscalls_pointers_override.h index 9fe0030..68ba1a2 100644 --- a/instrumentation/syscalls/headers/syscalls_pointers_override.h +++ b/instrumentation/syscalls/headers/syscalls_pointers_override.h @@ -1062,4 +1062,238 @@ SC_LTTNG_TRACEPOINT_EVENT_CODE(epoll_ctl, ) #endif /* defined(CONFIG_X86_32) || defined(CONFIG_X86_64) || defined(CONFIG_ARM64) || defined(CONFIG_ARM) */ +#ifndef ONCE_LTTNG_TRACE_EPOLL_H +#define ONCE_LTTNG_TRACE_EPOLL_H + +static struct lttng_event_field lttng_epoll_wait_fields[] = { + [0] = { + .name = "data_union", + .type = { + .atype = atype_struct, + .u._struct.nr_fields = ARRAY_SIZE(lttng_epoll_data_fields), + .u._struct.fields = lttng_epoll_data_fields, + } + }, + [1] = { + .name = "raw_events", + .type = __type_integer(uint32_t, 0, 0, 0, __BYTE_ORDER, 16, none), + }, + [2] = { + .name = "events", + .type = { + .atype = atype_struct, + .u._struct.nr_fields = ARRAY_SIZE(lttng_epoll_ctl_events_fields), + .u._struct.fields = lttng_epoll_ctl_events_fields, + } + }, +}; + +static struct lttng_type lttng_epoll_wait_elem = { + .atype = atype_struct, + .u._struct.nr_fields = ARRAY_SIZE(lttng_epoll_wait_fields), + .u._struct.fields = lttng_epoll_wait_fields, +}; + +#endif /* ONCE_LTTNG_TRACE_EPOLL_H */ + +#if defined(CONFIG_X86_32) || defined(CONFIG_X86_64) +#define OVERRIDE_32_epoll_wait +#define OVERRIDE_64_epoll_wait +SC_LTTNG_TRACEPOINT_EVENT_CODE(epoll_wait, + TP_PROTO(sc_exit(long ret,) int epfd, struct epoll_event __user * uevents, + int maxevents, int timeout), + TP_ARGS(sc_exit(ret,) epfd, uevents, maxevents, timeout), + TP_locvar( + sc_out( + unsigned int fds_length, overflow; + struct epoll_event *events; + ) + ), + TP_code_pre( + BUILD_BUG_ON(((ARRAY_SIZE(lttng_epoll_ctl_events_fields) - 1) + + EPOLL_FLAGS_PADDING_SIZE) != + sizeof(uint8_t) * BITS_PER_BYTE); + sc_out({ + int err; + unsigned long maxalloc; + + tp_locvar->fds_length = 0; + tp_locvar->events = NULL; + tp_locvar->overflow = 0; + + if (maxevents <= 0 || ret <= 0 || ret > maxevents) + goto skip_code; + + if ((maxevents * sizeof(struct epoll_event)) > PAGE_SIZE) { + maxalloc = PAGE_SIZE / sizeof(struct epoll_event); + if (ret > maxalloc) { + tp_locvar->fds_length = maxalloc; + tp_locvar->overflow = 1; + } else { + tp_locvar->fds_length = ret; + } + } else { + maxalloc = maxevents; + tp_locvar->fds_length = ret; + } + + tp_locvar->events = kmalloc( + maxalloc * sizeof(struct epoll_event), + GFP_ATOMIC); + if (!tp_locvar->events) { + tp_locvar->fds_length = 0; + goto skip_code; + } + + err = lib_ring_buffer_copy_from_user_check_nofault( + tp_locvar->events, uevents, + maxevents * sizeof(struct epoll_event)); + if (err != 0) + tp_locvar->fds_length = 0; + } + skip_code: + ) + ), + TP_FIELDS( + sc_exit(ctf_integer(long, ret, ret)) + sc_in(ctf_integer(int, epfd, epfd)) + sc_in(ctf_integer(int, maxevents, maxevents)) + sc_in(ctf_integer(int, timeout, timeout)) + sc_out(ctf_integer(unsigned int, fds_length, tp_locvar->fds_length)) + sc_out(ctf_integer(int, overflow, tp_locvar->overflow)) + sc_out( + ctf_custom_field( + ctf_custom_type( + .atype = atype_sequence_compound, + .u.sequence_compound.length_name = + "fds_length", + .u.sequence_compound.elem_type = + <tng_epoll_wait_elem, + ), + fds, + ctf_custom_code( + uint32_t i; + + ctf_align(uint64_t) + for (i = 0; i < tp_locvar->fds_length; i++) { + ctf_integer_type(uint64_t, tp_locvar->events[i].data) + ctf_integer_type(int, tp_locvar->events[i].data) + ctf_integer_bitfield_type(uint32_t, + cpu_to_le32(tp_locvar->events[i].events)) + ctf_integer_bitfield_type(uint8_t, + (uint8_t) cpu_to_le32(tp_locvar->events[i].events)) + } + ) + ) + ) + ), + TP_code_post( + sc_out( + kfree(tp_locvar->events); + ) + ) +) +#endif /* defined(CONFIG_X86_32) || defined(CONFIG_X86_64) */ + +#if defined(CONFIG_X86_32) || defined(CONFIG_X86_64) || defined(CONFIG_ARM64) || defined(CONFIG_ARM) +#define OVERRIDE_32_epoll_pwait +#define OVERRIDE_64_epoll_pwait +SC_LTTNG_TRACEPOINT_EVENT_CODE(epoll_pwait, + TP_PROTO(sc_exit(long ret,) int epfd, struct epoll_event __user * uevents, + int maxevents, int timeout, const sigset_t * sigmask, size_t sigsetsize), + TP_ARGS(sc_exit(ret,) epfd, uevents, maxevents, timeout, sigmask, sigsetsize), + TP_locvar( + sc_out( + unsigned int fds_length, overflow; + struct epoll_event *events; + ) + ), + TP_code_pre( + BUILD_BUG_ON(((ARRAY_SIZE(lttng_epoll_ctl_events_fields) - 1) + + EPOLL_FLAGS_PADDING_SIZE) != + sizeof(uint8_t) * BITS_PER_BYTE); + sc_out({ + int err; + unsigned long maxalloc; + + tp_locvar->fds_length = 0; + tp_locvar->events = NULL; + tp_locvar->overflow = 0; + + if (maxevents <= 0 || ret <= 0 || ret > maxevents) + goto skip_code; + + if ((maxevents * sizeof(struct epoll_event)) > PAGE_SIZE) { + maxalloc = PAGE_SIZE / sizeof(struct epoll_event); + if (ret > maxalloc) { + tp_locvar->fds_length = maxalloc; + tp_locvar->overflow = 1; + } else { + tp_locvar->fds_length = ret; + } + } else { + maxalloc = maxevents; + tp_locvar->fds_length = ret; + } + + tp_locvar->events = kmalloc( + maxalloc * sizeof(struct epoll_event), + GFP_ATOMIC); + if (!tp_locvar->events) { + tp_locvar->fds_length = 0; + goto skip_code; + } + + err = lib_ring_buffer_copy_from_user_check_nofault( + tp_locvar->events, uevents, + maxevents * sizeof(struct epoll_event)); + if (err != 0) + tp_locvar->fds_length = 0; + } + skip_code: + ) + ), + TP_FIELDS( + sc_exit(ctf_integer(long, ret, ret)) + sc_in(ctf_integer(int, epfd, epfd)) + sc_in(ctf_integer(int, maxevents, maxevents)) + sc_in(ctf_integer(int, timeout, timeout)) + sc_in(ctf_integer(const sigset_t *, sigmask, sigmask)) + sc_in(ctf_integer(size_t, sigsetsize, sigsetsize)) + sc_out(ctf_integer(unsigned int, fds_length, tp_locvar->fds_length)) + sc_out(ctf_integer(int, overflow, tp_locvar->overflow)) + sc_out( + ctf_custom_field( + ctf_custom_type( + .atype = atype_sequence_compound, + .u.sequence_compound.length_name = + "fds_length", + .u.sequence_compound.elem_type = + <tng_epoll_wait_elem, + ), + fds, + ctf_custom_code( + uint32_t i; + + ctf_align(uint64_t) + for (i = 0; i < tp_locvar->fds_length; i++) { + ctf_integer_type(uint64_t, tp_locvar->events[i].data) + ctf_integer_type(int, tp_locvar->events[i].data) + ctf_integer_bitfield_type(uint32_t, + cpu_to_le32(tp_locvar->events[i].events)) + ctf_integer_bitfield_type(uint8_t, + (uint8_t) cpu_to_le32(tp_locvar->events[i].events)) + } + ) + ) + ) + ), + TP_code_post( + sc_out( + kfree(tp_locvar->events); + ) + ) +) +#endif /* defined(CONFIG_X86_32) || defined(CONFIG_X86_64) || defined(CONFIG_ARM64) || defined(CONFIG_ARM) */ + #endif /* CREATE_SYSCALL_TABLE */ -- 1.9.1 _______________________________________________ lttng-dev mailing list lttng-dev@lists.lttng.org https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev