Adding dwarves@xxxxxxxxxxxxxxx to the CC list. Em Tue, Dec 18, 2018 at 02:09:38PM -0800, Yonghong Song escreveu: > This patch set included three btf related changes. > Patch #1 added support to do dwarf->btf conversion > for multiple cu's and multiple binaries. > Patch #2 added support to generate types for struct, > union and fwd using kind_flag. The kernel support > for kind_flag is here: > https://www.spinics.net/lists/netdev/msg539088.html > Patch #3 added func_proto support. The kernel support > is here: > https://www.spinics.net/lists/netdev/msg534643.html > Please see individual patch for details. > Yonghong Song (3): > btf: permit multiple cu's for dwarf->btf conversion > btf: fix struct/union/fwd types with kind_flag > btf: add func_proto support Ok, I tested and processed those and added a few more, adding a btf loader, pushed out to my git.kernel.org pahole repo. The btf loader is at: https://git.kernel.org/pub/scm/devel/pahole/pahole.git/commit/?id=472256d3c57bef53250686d55bd011f5dab4b657 Please take a look to see if I made some mistake. For a net/ipv4/tcp.o from a kernel build, for struct sk_buff, shows differences wrt the bit size of bitfield members, that is not encoded in BTF at the moment: $ pahole -F btf -C sk_buff ~/git/build/v4.20-rc5+/net/ipv4/tcp.o > /tmp/sk_buff.btf $ pahole -F dwarf -C sk_buff ~/git/build/v4.20-rc5+/net/ipv4/tcp.o > /tmp/sk_buff.dwarf $ diff -u /tmp/sk_buff.dwarf /tmp/sk_buff.btf --- /tmp/sk_buff.dwarf 2018-12-20 14:50:51.428653046 -0300 +++ /tmp/sk_buff.btf 2018-12-20 14:50:46.302601516 -0300 @@ -38,45 +38,45 @@ __u16 hdr_len; /* 138 2 */ __u16 queue_mapping; /* 140 2 */ __u8 __cloned_offset[0]; /* 142 0 */ - __u8 cloned:1; /* 142: 7 1 */ - __u8 nohdr:1; /* 142: 6 1 */ - __u8 fclone:2; /* 142: 4 1 */ - __u8 peeked:1; /* 142: 3 1 */ - __u8 head_frag:1; /* 142: 2 1 */ - __u8 xmit_more:1; /* 142: 1 1 */ - __u8 pfmemalloc:1; /* 142: 0 1 */ + __u8 cloned; /* 142 1 */ + __u8 nohdr; /* 142 1 */ + __u8 fclone; /* 142 1 */ + __u8 peeked; /* 142 1 */ + __u8 head_frag; /* 142 1 */ + __u8 xmit_more; /* 142 1 */ + __u8 pfmemalloc; /* 142 1 */ /* XXX 1 byte hole, try to pack */ __u32 headers_start[0]; /* 144 0 */ __u8 __pkt_type_offset[0]; /* 144 0 */ - __u8 pkt_type:3; /* 144: 5 1 */ - __u8 ignore_df:1; /* 144: 4 1 */ - __u8 nf_trace:1; /* 144: 3 1 */ - __u8 ip_summed:2; /* 144: 1 1 */ - __u8 ooo_okay:1; /* 144: 0 1 */ - __u8 l4_hash:1; /* 145: 7 1 */ - __u8 sw_hash:1; /* 145: 6 1 */ - __u8 wifi_acked_valid:1; /* 145: 5 1 */ - __u8 wifi_acked:1; /* 145: 4 1 */ - __u8 no_fcs:1; /* 145: 3 1 */ - __u8 encapsulation:1; /* 145: 2 1 */ - __u8 encap_hdr_csum:1; /* 145: 1 1 */ - __u8 csum_valid:1; /* 145: 0 1 */ - __u8 csum_complete_sw:1; /* 146: 7 1 */ - __u8 csum_level:2; /* 146: 5 1 */ - __u8 csum_not_inet:1; /* 146: 4 1 */ - __u8 dst_pending_confirm:1; /* 146: 3 1 */ - __u8 ndisc_nodetype:2; /* 146: 1 1 */ - __u8 ipvs_property:1; /* 146: 0 1 */ - __u8 inner_protocol_type:1; /* 147: 7 1 */ - __u8 remcsum_offload:1; /* 147: 6 1 */ - __u8 offload_fwd_mark:1; /* 147: 5 1 */ - __u8 offload_mr_fwd_mark:1; /* 147: 4 1 */ - __u8 tc_skip_classify:1; /* 147: 3 1 */ - __u8 tc_at_ingress:1; /* 147: 2 1 */ - __u8 tc_redirected:1; /* 147: 1 1 */ - __u8 tc_from_ingress:1; /* 147: 0 1 */ + __u8 pkt_type; /* 144 1 */ + __u8 ignore_df; /* 144 1 */ + __u8 nf_trace; /* 144 1 */ + __u8 ip_summed; /* 144 1 */ + __u8 ooo_okay; /* 144 1 */ + __u8 l4_hash; /* 145 1 */ + __u8 sw_hash; /* 145 1 */ + __u8 wifi_acked_valid; /* 145 1 */ + __u8 wifi_acked; /* 145 1 */ + __u8 no_fcs; /* 145 1 */ + __u8 encapsulation; /* 145 1 */ + __u8 encap_hdr_csum; /* 145 1 */ + __u8 csum_valid; /* 145 1 */ + __u8 csum_complete_sw; /* 146 1 */ + __u8 csum_level; /* 146 1 */ + __u8 csum_not_inet; /* 146 1 */ + __u8 dst_pending_confirm; /* 146 1 */ + __u8 ndisc_nodetype; /* 146 1 */ + __u8 ipvs_property; /* 146 1 */ + __u8 inner_protocol_type; /* 147 1 */ + __u8 remcsum_offload; /* 147 1 */ + __u8 offload_fwd_mark; /* 147 1 */ + __u8 offload_mr_fwd_mark; /* 147 1 */ + __u8 tc_skip_classify; /* 147 1 */ + __u8 tc_at_ingress; /* 147 1 */ + __u8 tc_redirected; /* 147 1 */ + __u8 tc_from_ingress; /* 147 1 */ __u16 tc_index; /* 148 2 */ /* XXX 2 bytes hole, try to pack */ $ For the whole net/ipv6/tcp.o: I'm getting a segfault when processing this entry: [acme@quaco pahole]$ pahole -F dwarf -C fpregs_state ~/git/build/v4.20-rc5+/net/ipv4/tcp.o union fpregs_state { struct fxregs_state fxsave; /* 0 512 */ struct swregs_state soft; /* 0 136 */ struct xregs_state xsave; /* 0 576 */ u8 __padding[4096]; /* 0 4096 */ }; [acme@quaco pahole]$ [acme@quaco pahole]$ pahole -F btf -C fpregs_state ~/git/build/v4.20-rc5+/net/ipv4/tcp.o Segmentation fault (core dumped) [acme@quaco pahole]$ Have to stop now, will try to fix this later, please let me know if you found the problem meanwhile :-) The difference up to the point where it tries to process that union is just related to bitfields: --- /tmp/tcp.o.dwarf.c 2018-12-20 15:00:09.249222711 -0300 +++ /tmp/tcp.o.btf.c 2018-12-20 15:22:00.935246130 -0300 @@ -81,11 +81,13 @@ const char * function; /* 8 8 */ const char * filename; /* 16 8 */ const char * format; /* 24 8 */ - unsigned int lineno:18; /* 32:14 4 */ - unsigned int flags:8; /* 32: 6 4 */ + unsigned int lineno; /* 32 4 */ - /* XXX 6 bits hole, try to pack */ - /* XXX 4 bytes hole, try to pack */ + /* Bitfield combined with next fields */ + + unsigned int flags; /* 34 4 */ + + /* XXX 2 bytes hole, try to pack */ union { struct static_key_true dd_key_true; /* 40 16 */ @@ -93,8 +95,7 @@ } key; /* 40 16 */ /* size: 56, cachelines: 1, members: 7 */ - /* sum members: 52, holes: 1, sum holes: 4 */ - /* bit holes: 1, sum bit holes: 6 bits */ + /* sum members: 54, holes: 1, sum holes: 2 */ /* last cacheline: 56 bytes */ }; struct file_operations { @@ -223,7 +224,11 @@ } futex; /* 8 40 */ struct { clockid_t clockid; /* 8 4 */ - enum timespec_type type; /* 12 4 */ + enum timespec_type type:4; /* 12: 0 1 */ + + /* XXX 4 bits hole, try to pack */ + /* XXX 3 bytes hole, try to pack */ + union { struct timespec * rmtp; /* 16 8 */ struct old_timespec32 * compat_rmtp; /* 16 8 */ @@ -320,22 +325,16 @@ long unsigned int jobctl; /* 1120 8 */ unsigned int personality; /* 1128 4 */ - unsigned int sched_reset_on_fork:1; /* 1132:31 4 */ - unsigned int sched_contributes_to_load:1; /* 1132:30 4 */ - unsigned int sched_migrated:1; /* 1132:29 4 */ - unsigned int sched_remote_wakeup:1; /* 1132:28 4 */ - - /* XXX 28 bits hole, try to pack */ - - unsigned int in_execve:1; /* 1136:31 4 */ - unsigned int in_iowait:1; /* 1136:30 4 */ - unsigned int restore_sigmask:1; /* 1136:29 4 */ - unsigned int in_user_fault:1; /* 1136:28 4 */ - unsigned int no_cgroup_migration:1; /* 1136:27 4 */ - unsigned int use_memdelay:1; /* 1136:26 4 */ - - /* XXX 26 bits hole, try to pack */ - + unsigned int sched_reset_on_fork; /* 1132 4 */ + unsigned int sched_contributes_to_load; /* 1132 4 */ + unsigned int sched_migrated; /* 1132 4 */ + unsigned int sched_remote_wakeup; /* 1132 4 */ + unsigned int in_execve; /* 1136 4 */ + unsigned int in_iowait; /* 1136 4 */ + unsigned int restore_sigmask; /* 1136 4 */ + unsigned int in_user_fault; /* 1136 4 */ + unsigned int no_cgroup_migration; /* 1136 4 */ + unsigned int use_memdelay; /* 1136 4 */ unsigned int kernel_uaccess_faults_ok; /* 1140 4 */ long unsigned int atomic_flags; /* 1144 8 */ /* --- cacheline 18 boundary (1152 bytes) --- */ @@ -548,7 +547,6 @@ /* size: 11008, cachelines: 172, members: 207 */ /* sum members: 10906, holes: 15, sum holes: 102 */ - /* bit holes: 2, sum bit holes: 54 bits */ /* paddings: 3, sum paddings: 14 */ }; struct screen_info { @@ -811,40 +809,64 @@ struct desc_struct { u16 limit0; /* 0 2 */ u16 base0; /* 2 2 */ - u16 base1:8; /* 4: 8 2 */ - u16 type:4; /* 4: 4 2 */ - u16 s:1; /* 4: 3 2 */ - u16 dpl:2; /* 4: 1 2 */ - u16 p:1; /* 4: 0 2 */ - u16 limit1:4; /* 6:12 2 */ - u16 avl:1; /* 6:11 2 */ - u16 l:1; /* 6:10 2 */ - u16 d:1; /* 6: 9 2 */ - u16 g:1; /* 6: 8 2 */ - u16 base2:8; /* 6: 0 2 */ + u16 base1; /* 4 2 */ + + /* Bitfield combined with next fields */ + + u16 type; /* 5 2 */ + u16 s; /* 5 2 */ + u16 dpl; /* 5 2 */ + u16 p; /* 5 2 */ + + /* Bitfield combined with next fields */ + + u16 limit1; /* 6 2 */ + u16 avl; /* 6 2 */ + u16 l; /* 6 2 */ + u16 d; /* 6 2 */ + u16 g; /* 6 2 */ + + /* Bitfield combined with next fields */ + + u16 base2; /* 7 2 */ /* size: 8, cachelines: 1, members: 13 */ + /* padding: 65535 */ /* last cacheline: 8 bytes */ + + /* BRAIN FART ALERT! 8 != 9 + 0(holes), diff = -1 */ + }; struct idt_bits { - u16 ist:3; /* 0:13 2 */ - u16 zero:5; /* 0: 8 2 */ - u16 type:5; /* 0: 3 2 */ - u16 dpl:2; /* 0: 1 2 */ - u16 p:1; /* 0: 0 2 */ + u16 ist; /* 0 2 */ + u16 zero; /* 0 2 */ + + /* Bitfield combined with next fields */ + + u16 type; /* 1 2 */ + u16 dpl; /* 1 2 */ + u16 p; /* 1 2 */ /* size: 2, cachelines: 1, members: 5 */ + /* padding: 65535 */ /* last cacheline: 2 bytes */ + + /* BRAIN FART ALERT! 2 != 3 + 0(holes), diff = -1 */ + }; struct gate_struct { u16 offset_low; /* 0 2 */ u16 segment; /* 2 2 */ struct idt_bits bits; /* 4 2 */ + + /* XXX last struct has 65535 bytes of padding */ + u16 offset_middle; /* 6 2 */ u32 offset_high; /* 8 4 */ u32 reserved; /* 12 4 */ /* size: 16, cachelines: 1, members: 6 */ + /* paddings: 1, sum paddings: 65535 */ /* last cacheline: 16 bytes */ }; struct desc_ptr { @@ -884,9 +906,15 @@ void * s_mem; /* 40 8 */ long unsigned int counters; /* 40 8 */ struct { - unsigned int inuse:16; /* 40:16 4 */ - unsigned int objects:15; /* 40: 1 4 */ - unsigned int frozen:1; /* 40: 0 4 */ + unsigned int inuse; /* 40 4 */ + + /* Bitfield combined with next fields */ + + unsigned int objects; /* 42 4 */ + + /* Bitfield combined with next fields */ + + unsigned int frozen; /* 43 4 */ }; /* 40 4 */ }; /* 40 8 */ }; /* 8 40 */ @@ -1039,10 +1067,9 @@ /* XXX 4 bytes hole, try to pack */ mm_segment_t addr_limit; /* 152 8 */ - unsigned int sig_on_uaccess_err:1; /* 160:31 4 */ - unsigned int uaccess_err:1; /* 160:30 4 */ + unsigned int sig_on_uaccess_err; /* 160 4 */ + unsigned int uaccess_err; /* 160 4 */ - /* XXX 30 bits hole, try to pack */ /* XXX 28 bytes hole, try to pack */ /* --- cacheline 3 boundary (192 bytes) --- */ @@ -1050,7 +1077,6 @@ /* size: 4352, cachelines: 68, members: 21 */ /* sum members: 4320, holes: 2, sum holes: 32 */ - /* bit holes: 1, sum bit holes: 30 bits */ }; struct pv_irq_ops { struct paravirt_callee_save save_fl; /* 0 8 */
