Re: [Crash-utility] [PATCH 1/2] ps: Add support to "ps -l" to properly display process list

Thank you for the patch, Austin. On Fri, Feb 25, 2022 at 4:52 PM <crash-utility-request(a)redhat.com&gt; wrote: > > Date: Fri, 25 Feb 2022 07:19:32 +0000 > From: Austin Kim <austindh.kim(a)gmail.com&gt; > To: k-hagio-ab(a)nec.com, crash-utility(a)redhat.com > Cc: kernel-team(a)lge.com, mikeseohyungjin(a)gmail.com > Subject: [Crash-utility] [PATCH 1/2] ps: Add support to "ps -l" to > properly display process list > Message-ID: <20220225071932.GA1097@raspberrypi> > Content-Type: text/plain; charset=us-ascii > > Sometimes kernel image is generated without CONFIG_SCHED_STAT or CONFIG_SCHED_INFO. > > Running crash-utility with above kernel image, > "ps -l" options cannot display all processes sorted with most recently-run process > > crash> ps -l > ps: last-run timestamps do not exist in this kernel > Usage: > ps [-k|-u|-G] [-s] [-p|-c|-t|-[l|m][-C cpu]|-a|-g|-r|-S] > [pid | task | command] ... > Enter "help ps" for details. > > This is because output of 'ps -l' depends on task_struct.sched_info.last_arrival. > Without CONFIG_SCHED_STAT or CONFIG_SCHED_INFO, 'sched_info' field is not included > in task_struct. > > So we make 'ps -e' option to access 'exec_start' field of sched_entity. > where 'exec_start' is task_struct.se.exec_start. > > With this patch, "ps -l" option works well without CONFIG_SCHED_STAT or > CONFIG_SCHED_INFO. > > The history of CONFIG_SCHED_INFO and CONFIG_SCHED_STAT is as below; > > - CONFIG_SCHED_INFO: KERNEL_VERSION >= LINUX(4,2,0) > - CONFIG_SCHED_STAT: KERNEL_VERSION < LINUX(4,2,0) > Could you please add the kernel commit ID for the relevant changes?

In addition, I would suggest to fold these two patches as one patch and change the subject as: "ps: Add support to "ps -l|-m" to properly display process list", what do you think?

> Signed-off-by: Austin Kim <austindh.kim(a)gmail.com&gt; > --- > defs.h | 2 ++ > symbols.c | 2 ++ > task.c | 17 ++++++++++++++--- > 3 files changed, 18 insertions(+), 3 deletions(-) > > diff --git a/defs.h b/defs.h > index 7d386d2..ed2f5ca 100644 > --- a/defs.h > +++ b/defs.h > @@ -1768,6 +1768,8 @@ struct offset_table { /* stash of commonly-used offsets */ > long vcpu_struct_rq; > long task_struct_sched_info; > long sched_info_last_arrival; > + long task_struct_sched_entity; > + long se_exec_start; This can be only appended to the end of the offset_table. For more details, refer to the section "writing patches" in wiki: https://github.com/crash-utility/crash/wiki

Thanks. Lianbo > long page_objects; > long kmem_cache_oo; > long char_device_struct_cdev; > diff --git a/symbols.c b/symbols.c > index 97fb778..5e2032a 100644 > --- a/symbols.c > +++ b/symbols.c > @@ -8892,6 +8892,8 @@ dump_offset_table(char *spec, ulong makestruct) > OFFSET(sched_rt_entity_run_list)); > fprintf(fp, " sched_info_last_arrival: %ld\n", > OFFSET(sched_info_last_arrival)); > + fprintf(fp, " se_exec_start: %ld\n", > + OFFSET(se_exec_start)); > fprintf(fp, " task_struct_thread_info: %ld\n", > OFFSET(task_struct_thread_info)); > fprintf(fp, " task_struct_stack: %ld\n", > diff --git a/task.c b/task.c > index 864c838..e6fde74 100644 > --- a/task.c > +++ b/task.c > @@ -334,9 +334,15 @@ task_init(void) > if (VALID_MEMBER(task_struct_sched_info)) > MEMBER_OFFSET_INIT(sched_info_last_arrival, > "sched_info", "last_arrival"); > + MEMBER_OFFSET_INIT(task_struct_sched_entity, "task_struct", "se"); > + if (VALID_MEMBER(task_struct_sched_entity)) { > + STRUCT_SIZE_INIT(sched_entity, "sched_entity"); > + MEMBER_OFFSET_INIT(se_exec_start, "sched_entity", "exec_start"); > + } > if (VALID_MEMBER(task_struct_last_run) || > VALID_MEMBER(task_struct_timestamp) || > - VALID_MEMBER(sched_info_last_arrival)) { > + VALID_MEMBER(sched_info_last_arrival) || > + VALID_MEMBER(se_exec_start)) { > char buf[BUFSIZE]; > strcpy(buf, "alias last ps -l"); > alias_init(buf); > @@ -3574,7 +3580,8 @@ cmd_ps(void) > case 'l': > if (INVALID_MEMBER(task_struct_last_run) && > INVALID_MEMBER(task_struct_timestamp) && > - INVALID_MEMBER(sched_info_last_arrival)) { > + INVALID_MEMBER(sched_info_last_arrival) && > + INVALID_MEMBER(se_exec_start)) { > error(INFO, > "last-run timestamps do not exist in this kernel\n"); > argerrs++; > @@ -6020,7 +6027,11 @@ task_last_run(ulong task) > timestamp = tt->last_task_read ? ULONGLONG(tt->task_struct + > OFFSET(task_struct_sched_info) + > OFFSET(sched_info_last_arrival)) : 0; > - > + else if (VALID_MEMBER(se_exec_start)) > + timestamp = tt->last_task_read ? ULONGLONG(tt->task_struct + > + OFFSET(task_struct_sched_entity) + > + OFFSET(se_exec_start)) : 0; > + > return timestamp; > } > > -- > 2.20.1