ftrace: Fix a few issues
v2 cover ftrace: Fix a few issues
This is v2 of the patches posted at:
https://www.mail-archive.com/[email protected]/msg1395670.html
Changes:
- Patch 1 has been updated to actually simplify the check for glob
- Patch 2 has been updated to guard the call to clear_ftrace_function_probes() in trace.c with the proper #ifdef's
- Patches 3 and 4 are the same as in v1.
- Naveen
Naveen N. Rao (4):
ftrace: Simplify glob handling in
unregister_ftrace_function_probe_func()
ftrace/instances: Clear function triggers when removing instances selftests/ftrace: Fix bashisms
selftests/ftrace: Add test to remove instance with active event
triggers
kernel/trace/ftrace.c | 12 ++++++++++-- kernel/trace/trace.c | 3 +++ kernel/trace/trace.h | 1 + tools/testing/selftests/ftrace/ftracetest | 2 +- .../selftests/ftrace/test.d/ftrace/func_event_triggers.tc | 2 +- tools/testing/selftests/ftrace/test.d/functions | 4 ++-- .../selftests/ftrace/test.d/instances/instance-event.tc | 8 ++++++-- 7 files changed, 24 insertions(+), 8 deletions(-)
Signature · 1 line
2.12.2
PATCH v2 1/4 ftrace: Simplify glob handling in unregister_ftrace_function_probe_func()
Handle a NULL glob properly and simplify the check.
Signed-off-by Naveen N. Rao <[email protected]>
--- kernel/trace/ftrace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
kernel/trace/ftrace.c +2 -2
@@ -4144,9 +4144,9 @@ unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,int i, ret = -ENODEV ;int size; -if (glob && (strcmp (glob,"*" ) ==0 || !strlen (glob))) +if (!glob || !strlen (glob) || !strcmp (glob,"*" )) func_g.search =NULL ; -else if (glob) { +else {int not; func_g.type = filter_parse_regex(glob, strlen(glob),
Signature · 1 line
2.12.2
Re: [PATCH v2 1/4] ftrace: Simplify glob handling in unregister_ftrace_function_probe_func()
Quoted 2 lines · On Tue, 16 May 2017 23:21:25 +0530 "Naveen N. Rao"…
Handle a NULL glob properly and simplify the check.
Looks good to me.
Reviewed-by Masami Hiramatsu <[email protected]>
Thanks!
Quoted 24 lines
Signed-off-by Naveen N. Rao <[email protected]>--- kernel/trace/ftrace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)kernel/trace/ftrace.c +2
-2@@ -4144,9 +4144,9 @@ unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,int i, ret = -ENODEV ;int size; -if (glob && (strcmp (glob,"*" ) ==0 || !strlen (glob))) +if (!glob || !strlen (glob) || !strcmp (glob,"*" )) func_g.search =NULL ; -else if (glob) { +else {int not; func_g.type = filter_parse_regex(glob, strlen(glob),Signature · 1 line
2.12.2
Signature · 1 line
Masami Hiramatsu <[email protected]>
PATCH v2 2/4 ftrace/instances: Clear function triggers when removing instances
In reply to Naveen N. RaoIf instance directories are deleted while there are registered function triggers:
# cd /sys/kernel/debug/tracing/instances
# mkdir test
# echo "schedule:enable_event:sched:sched_switch" > test/set_ftrace_filter
# rmdir test
Unable to handle kernel paging request for data at address 0x00000008
Unable to handle kernel paging request for data at address 0x00000008
Faulting instruction address: 0xc0000000021edde8
Oops: Kernel access of bad area, sig: 11 [#1]
SMP NR_CPUS=2048
NUMA
pSeries
Modules linked in: iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack ipt_REJECT nf_reject_ipv4 xt_tcpudp tun bridge stp llc kvm iptable_filter fuse binfmt_misc pseries_rng rng_core vmx_crypto ib_iser rdma_cm iw_cm ib_cm ib_core libiscsi scsi_transport_iscsi ip_tables x_tables autofs4 btrfs raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c multipath virtio_net virtio_blk virtio_pci crc32c_vpmsum virtio_ring virtio
CPU: 8 PID: 8694 Comm: rmdir Not tainted 4.11.0-nnr+ #113
task: c0000000bab52800 task.stack: c0000000baba0000
NIP: c0000000021edde8 LR: c0000000021f0590 CTR: c000000002119620
REGS: c0000000baba3870 TRAP: 0300 Not tainted (4.11.0-nnr+)
MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE>
CR: 22002422 XER: 20000000
CFAR: 00007fffabb725a8 DAR: 0000000000000008 DSISR: 40000000 SOFTE: 0
GPR00: c00000000220f750 c0000000baba3af0 c000000003157e00 0000000000000000
GPR04: 0000000000000040 00000000000000eb 0000000000000040 0000000000000000
GPR08: 0000000000000000 0000000000000113 0000000000000000 c00000000305db98
GPR12: c000000002119620 c00000000fd42c00 0000000000000000 0000000000000000
GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR20: 0000000000000000 0000000000000000 c0000000bab52e90 0000000000000000
GPR24: 0000000000000000 00000000000000eb 0000000000000040 c0000000baba3bb0
GPR28: c00000009cb06eb0 c0000000bab52800 c00000009cb06eb0 c0000000baba3bb0
NIP [c0000000021edde8] ring_buffer_lock_reserve+0x8/0x4e0
LR [c0000000021f0590] trace_event_buffer_lock_reserve+0xe0/0x1a0
Call Trace:
[c0000000baba3af0] [c0000000021f96c8] trace_event_buffer_commit+0x1b8/0x280 (unreliable)
[c0000000baba3b60] [c00000000220f750] trace_event_buffer_reserve+0x80/0xd0
[c0000000baba3b90] [c0000000021196b8] trace_event_raw_event_sched_switch+0x98/0x180
[c0000000baba3c10] [c0000000029d9980] __schedule+0x6e0/0xab0
[c0000000baba3ce0] [c000000002122230] do_task_dead+0x70/0xc0
[c0000000baba3d10] [c0000000020ea9c8] do_exit+0x828/0xd00
[c0000000baba3dd0] [c0000000020eaf70] do_group_exit+0x60/0x100
[c0000000baba3e10] [c0000000020eb034] SyS_exit_group+0x24/0x30
[c0000000baba3e30] [c00000000200bcec] system_call+0x38/0x54
Instruction dump:
60000000 60420000 7d244b78 7f63db78 4bffaa09 393efff8 793e0020 39200000
4bfffecc 60420000 3c4c00f7 3842a020 <81230008> 2f890000 409e02f0 a14d0008
---[ end trace b917b8985d0e650b ]---
Unable to handle kernel paging request for data at address 0x00000008
Faulting instruction address: 0xc0000000021edde8
Unable to handle kernel paging request for data at address 0x00000008
Faulting instruction address: 0xc0000000021edde8
Faulting instruction address: 0xc0000000021edde8To address this, let's clear all registered function probes before deleting the ftrace instance.
Reported-by Michael Ellerman <[email protected]>
Signed-off-by Naveen N. Rao <[email protected]>
--- kernel/trace/ftrace.c | 8 ++++++++ kernel/trace/trace.c | 3 +++ kernel/trace/trace.h | 1 + 3 files changed, 12 insertions(+)
kernel/trace/ftrace.c +8 -0
@@ -4256,6 +4256,14 @@ unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,return ret; } +void clear_ftrace_function_probes (struct trace_array *tr) +{ +struct ftrace_func_probe *probe, *n; + +list_for_each_entry_safe (probe, n, &tr->func_probes, list) +unregister_ftrace_function_probe_func (NULL , tr, probe->probe_ops); +} +static LIST_HEAD (ftrace_commands);static DEFINE_MUTEX (ftrace_cmd_mutex);
kernel/trace/trace.c +3 -0
@@ -7550,6 +7550,9 @@ static int instance_rmdir(const char *name) }tracing_set_nop (tr); +#if defined(CONFIG_FUNCTION_TRACER ) && defined(CONFIG_DYNAMIC_FTRACE ) +clear_ftrace_function_probes (tr); +#endif event_trace_del_tracer (tr);ftrace_clear_pids (tr);ftrace_destroy_function_files (tr);
kernel/trace/trace.h +1 -0
@@ -980,6 +980,7 @@ register_ftrace_function_probe(char *glob, struct trace_array *tr,extern int unregister_ftrace_function_probe_func (char *glob,struct trace_array *tr,struct ftrace_probe_ops *ops); +extern void clear_ftrace_function_probes (struct trace_array *tr);int register_ftrace_command (struct ftrace_func_command *cmd);int unregister_ftrace_command (struct ftrace_func_command *cmd);
Signature · 1 line
2.12.2
PATCH v2 3/4 selftests/ftrace: Fix bashisms
In reply to Naveen N. RaoFix a few bashisms in ftrace selftests.
Acked-by Masami Hiramatsu <[email protected]>
Signed-off-by Naveen N. Rao <[email protected]>
--- tools/testing/selftests/ftrace/ftracetest | 2 +- tools/testing/selftests/ftrace/test.d/ftrace/func_event_triggers.tc | 2 +- tools/testing/selftests/ftrace/test.d/functions | 4 ++-- 3 files changed, 4 insertions(+), 4 deletions(-)
tools/testing/selftests/ftrace/ftracetest +1 -1
@@ -58,7 +58,7 @@ parse_opts() { # opts ;; --verbose|-v|-vv) VERBOSE=$((VERBOSE + 1)) - [ $1 == '-vv' ] && VERBOSE=$((VERBOSE + 1)) + [ $1 = '-vv' ] && VERBOSE=$((VERBOSE + 1)) shift 1 ;; --debug|-d)
tools/testing/selftests/ftrace/test.d/ftrace/func_event_triggers.tc +1 -1
@@ -48,7 +48,7 @@ test_event_enabled() { e=`cat $EVENT_ENABLE` if [ "$e" != $val ]; then echo "Expected $val but found $e" - exit -1 + exit 1 fi }
tools/testing/selftests/ftrace/test.d/functions +2 -2
@@ -34,10 +34,10 @@ reset_ftrace_filter() { # reset all triggers in set_ftrace_filter echo > set_ftrace_filter grep -v '^#' set_ftrace_filter | while read t; do tr=`echo $t | cut -d: -f2` - if [ "$tr" == "" ]; then + if [ "$tr" = "" ]; then continue fi - if [ $tr == "enable_event" -o $tr == "disable_event" ]; then + if [ $tr = "enable_event" -o $tr = "disable_event" ]; then tr=`echo $t | cut -d: -f1-4` limit=`echo $t | cut -d: -f5` else
Signature · 1 line
2.12.2
PATCH v2 4/4 selftests/ftrace: Add test to remove instance with active event triggers
In reply to Naveen N. RaoAdd a test to ensure we clean up properly when removing an instance with active event triggers.
Signed-off-by Naveen N. Rao <[email protected]>
--- tools/testing/selftests/ftrace/test.d/instances/instance-event.tc | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
tools/testing/selftests/ftrace/test.d/instances/instance-event.tc +6 -2
@@ -75,9 +75,13 @@ rmdir foo if [ -d foo ]; then fail "foo still exists" fi -exit 0 - +mkdir foo +echo "schedule:enable_event:sched:sched_switch" > foo/set_ftrace_filter +rmdir foo +if [ -d foo ]; then + fail "foo still exists" +fi instance_slam() {
Signature · 1 line
2.12.2