* Re: [PATCH 2/2] blktrace: fix output of BLK_TC_PC events
2009-04-01 8:19 ` [PATCH 2/2] blktrace: fix output of BLK_TC_PC events Li Zefan
@ 2009-04-01 11:00 ` Ingo Molnar
2009-04-01 12:52 ` Arnaldo Carvalho de Melo
2009-04-11 8:15 ` Li Zefan
2009-04-13 22:22 ` [tip:tracing/core] " tip-bot for Li Zefan
2 siblings, 1 reply; 13+ messages in thread
From: Ingo Molnar @ 2009-04-01 11:00 UTC (permalink / raw)
To: Li Zefan
Cc: Jens Axboe, Arnaldo Carvalho de Melo, Steven Rostedt,
Frederic Weisbecker, LKML
* Li Zefan <lizf@cn.fujitsu.com> wrote:
> BLK_TC_PC events should be treated differently with BLK_TC_FS events.
>
> Before this patch:
>
> # echo 1 > /sys/block/sda/sda1/trace/enable
> # echo pc > /sys/block/sda/sda1/trace/act_mask
> # echo blk > /debugfs/tracing/current_tracer
> # (generate some BLK_TC_PC events)
> # cat trace
> bash-2184 [000] 1774.275413: 8,7 I N [bash]
> bash-2184 [000] 1774.275435: 8,7 D N [bash]
> bash-2184 [000] 1774.275540: 8,7 I R [bash]
> bash-2184 [000] 1774.275547: 8,7 D R [bash]
> ksoftirqd/0-4 [000] 1774.275580: 8,7 C N 0 [0]
> bash-2184 [000] 1774.275648: 8,7 I R [bash]
> bash-2184 [000] 1774.275653: 8,7 D R [bash]
> ksoftirqd/0-4 [000] 1774.275682: 8,7 C N 0 [0]
> bash-2184 [000] 1774.275739: 8,7 I R [bash]
> bash-2184 [000] 1774.275744: 8,7 D R [bash]
> ksoftirqd/0-4 [000] 1774.275771: 8,7 C N 0 [0]
> bash-2184 [000] 1774.275804: 8,7 I R [bash]
> bash-2184 [000] 1774.275808: 8,7 D R [bash]
> ksoftirqd/0-4 [000] 1774.275836: 8,7 C N 0 [0]
>
> After this patch:
>
> # cat trace
> bash-2263 [000] 366.782149: 8,7 I N 0 (00 ..) [bash]
> bash-2263 [000] 366.782323: 8,7 D N 0 (00 ..) [bash]
> bash-2263 [000] 366.782557: 8,7 I R 8 (25 00 ..) [bash]
> bash-2263 [000] 366.782560: 8,7 D R 8 (25 00 ..) [bash]
> ksoftirqd/0-4 [000] 366.782582: 8,7 C N (25 00 ..) [0]
> bash-2263 [000] 366.782648: 8,7 I R 8 (5a 00 3f 00) [bash]
> bash-2263 [000] 366.782650: 8,7 D R 8 (5a 00 3f 00) [bash]
> ksoftirqd/0-4 [000] 366.782669: 8,7 C N (5a 00 3f 00) [0]
> bash-2263 [000] 366.782710: 8,7 I R 8 (5a 00 08 00) [bash]
> bash-2263 [000] 366.782713: 8,7 D R 8 (5a 00 08 00) [bash]
> ksoftirqd/0-4 [000] 366.782730: 8,7 C N (5a 00 08 00) [0]
> bash-2263 [000] 366.783375: 8,7 I R 36 (5a 00 08 00) [bash]
> bash-2263 [000] 366.783379: 8,7 D R 36 (5a 00 08 00) [bash]
> ksoftirqd/0-4 [000] 366.783404: 8,7 C N (5a 00 08 00) [0]
>
> This is what we do with PC events in user-space blktrace.
>
> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
> ---
> kernel/trace/blktrace.c | 88 ++++++++++++++++++++++++++++++++++++++++++----
> 1 files changed, 80 insertions(+), 8 deletions(-)
>
> diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
> index 464a6e5..fd1ff49 100644
> --- a/kernel/trace/blktrace.c
> +++ b/kernel/trace/blktrace.c
> @@ -970,6 +970,16 @@ static inline const void *pdu_start(const struct trace_entry *ent)
> return te_blk_io_trace(ent) + 1;
> }
>
> +static inline u32 t_action(const struct trace_entry *ent)
> +{
> + return te_blk_io_trace(ent)->action;
> +}
> +
> +static inline u32 t_bytes(const struct trace_entry *ent)
> +{
> + return te_blk_io_trace(ent)->bytes;
> +}
> +
> static inline u32 t_sec(const struct trace_entry *ent)
> {
> return te_blk_io_trace(ent)->bytes >> 9;
> @@ -1030,25 +1040,87 @@ static int blk_log_action(struct trace_iterator *iter, const char *act)
> MAJOR(t->device), MINOR(t->device), act, rwbs);
> }
>
> +static int blk_log_dump_pdu(struct trace_seq *s, const struct trace_entry *ent)
> +{
> + const char *pdu_buf;
> + int pdu_len;
> + int i, end, ret;
> +
> + pdu_buf = pdu_start(ent);
> + pdu_len = te_blk_io_trace(ent)->pdu_len;
> +
> + if (!pdu_len)
> + return 1;
> +
> + /* find the last zero that needs to be printed */
> + for (end = pdu_len - 1; end >= 0; end--)
> + if (pdu_buf[end])
> + break;
> + end++;
> +
> + if (!trace_seq_putc(s, '('))
> + return 0;
> +
> + for (i = 0; i < pdu_len; i++) {
> +
> + ret = trace_seq_printf(s, "%s%02x",
> + i == 0 ? "" : " ", pdu_buf[i]);
> + if (!ret)
> + return ret;
> +
> + /*
> + * stop when the rest is just zeroes and indicate so
> + * with a ".." appended
> + */
> + if (i == end && end != pdu_len - 1)
> + return trace_seq_puts(s, " ..) ");
> + }
> +
> + return trace_seq_puts(s, ") ");
> +}
> +
> static int blk_log_generic(struct trace_seq *s, const struct trace_entry *ent)
> {
> char cmd[TASK_COMM_LEN];
>
> trace_find_cmdline(ent->pid, cmd);
>
> - if (t_sec(ent))
> - return trace_seq_printf(s, "%llu + %u [%s]\n",
> - t_sector(ent), t_sec(ent), cmd);
> - return trace_seq_printf(s, "[%s]\n", cmd);
> + if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) {
> + int ret;
> +
> + ret = trace_seq_printf(s, "%u ", t_bytes(ent));
> + if (!ret)
> + return 0;
> + ret = blk_log_dump_pdu(s, ent);
> + if (!ret)
> + return 0;
> + return trace_seq_printf(s, "[%s]\n", cmd);
> + } else {
> + if (t_sec(ent))
> + return trace_seq_printf(s, "%llu + %u [%s]\n",
> + t_sector(ent), t_sec(ent), cmd);
> + return trace_seq_printf(s, "[%s]\n", cmd);
> + }
> }
>
> static int blk_log_with_error(struct trace_seq *s,
> const struct trace_entry *ent)
> {
> - if (t_sec(ent))
> - return trace_seq_printf(s, "%llu + %u [%d]\n", t_sector(ent),
> - t_sec(ent), t_error(ent));
> - return trace_seq_printf(s, "%llu [%d]\n", t_sector(ent), t_error(ent));
> + if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) {
> + int ret;
> +
> + ret = blk_log_dump_pdu(s, ent);
> + if (ret)
> + return trace_seq_printf(s, "[%d]\n", t_error(ent));
> + return 0;
> + } else {
> + if (t_sec(ent))
> + return trace_seq_printf(s, "%llu + %u [%d]\n",
> + t_sector(ent),
> + t_sec(ent), t_error(ent));
> + return trace_seq_printf(s, "%llu [%d]\n",
> + t_sector(ent), t_error(ent));
> + }
> }
>
> static int blk_log_remap(struct trace_seq *s, const struct trace_entry *ent)
Neat shortcut - packet command requests can be quite large in
special cases, right?
Sidenote. Right now we reserve the full packet length in the trace
buffer, then copy the full packet into the trace buffer:
if (pdu_len)
memcpy((void *) t + sizeof(*t), pdu_data, pdu_len);
... just to scan it a second time during output and discard much of
it later on if it has a lot of trailing zeroes.
It might make sense to pre-compress: by extending the trace record
format with a trailing-zeroes field.
But that would make it more complex and key to tracers is simplicity
of data acquisition.
Dunno, probably not worth it, except if data stream bloat becomes a
real issue (which i'd not expect them to become in this case).
Anyway - Jens, the two patches look good to me, do they look fine to
you too?
Ingo
^ permalink raw reply [flat|nested] 13+ messages in thread* Re: [PATCH 2/2] blktrace: fix output of BLK_TC_PC events
2009-04-01 11:00 ` Ingo Molnar
@ 2009-04-01 12:52 ` Arnaldo Carvalho de Melo
0 siblings, 0 replies; 13+ messages in thread
From: Arnaldo Carvalho de Melo @ 2009-04-01 12:52 UTC (permalink / raw)
To: Ingo Molnar
Cc: Li Zefan, Jens Axboe, Steven Rostedt, Frederic Weisbecker, LKML
Em Wed, Apr 01, 2009 at 01:00:16PM +0200, Ingo Molnar escreveu:
>
> * Li Zefan <lizf@cn.fujitsu.com> wrote:
>
> > + } else {
> > + if (t_sec(ent))
> > + return trace_seq_printf(s, "%llu + %u [%d]\n",
> > + t_sector(ent),
> > + t_sec(ent), t_error(ent));
> > + return trace_seq_printf(s, "%llu [%d]\n",
> > + t_sector(ent), t_error(ent));
> > + }
> > }
> >
> > static int blk_log_remap(struct trace_seq *s, const struct trace_entry *ent)
>
> Neat shortcut - packet command requests can be quite large in
> special cases, right?
>
> Sidenote. Right now we reserve the full packet length in the trace
> buffer, then copy the full packet into the trace buffer:
>
> if (pdu_len)
> memcpy((void *) t + sizeof(*t), pdu_data, pdu_len);
>
> ... just to scan it a second time during output and discard much of
> it later on if it has a lot of trailing zeroes.
>
> It might make sense to pre-compress: by extending the trace record
> format with a trailing-zeroes field.
You mean something like asking, at tracer registration time to do this
kind of compression and have it done on the core tracing code? Looks
worthy if we can find a second tracer that would benefit from the space
savings at the cost of using more CPU at each event.
But perhaps providing a "memcpy" replacement to be used in such things
and leaving this to the user to decide, i.e. it may be interesting in
certain scenarios to be able to do:
echo 1 > /sys/kernel/debug/tracing/options/compress
And have the payload compressed.
> But that would make it more complex and key to tracers is simplicity
> of data acquisition.
>
> Dunno, probably not worth it, except if data stream bloat becomes a
> real issue (which i'd not expect them to become in this case).
>
> Anyway - Jens, the two patches look good to me, do they look fine to
> you too?
To me too,
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
to this one too.
- Arnaldo
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH 2/2] blktrace: fix output of BLK_TC_PC events
2009-04-01 8:19 ` [PATCH 2/2] blktrace: fix output of BLK_TC_PC events Li Zefan
2009-04-01 11:00 ` Ingo Molnar
@ 2009-04-11 8:15 ` Li Zefan
2009-04-12 13:07 ` Ingo Molnar
2009-04-13 22:22 ` [tip:tracing/core] " tip-bot for Li Zefan
2 siblings, 1 reply; 13+ messages in thread
From: Li Zefan @ 2009-04-11 8:15 UTC (permalink / raw)
To: Ingo Molnar
Cc: Jens Axboe, Arnaldo Carvalho de Melo, Steven Rostedt,
Frederic Weisbecker, LKML
Hi Ingo,
I would like to ask what's the status of these 2 patches.
Arnaldo acked on them.
Li Zefan wrote:
> BLK_TC_PC events should be treated differently with BLK_TC_FS events.
>
> Before this patch:
>
> # echo 1 > /sys/block/sda/sda1/trace/enable
> # echo pc > /sys/block/sda/sda1/trace/act_mask
> # echo blk > /debugfs/tracing/current_tracer
> # (generate some BLK_TC_PC events)
> # cat trace
> bash-2184 [000] 1774.275413: 8,7 I N [bash]
> bash-2184 [000] 1774.275435: 8,7 D N [bash]
> bash-2184 [000] 1774.275540: 8,7 I R [bash]
> bash-2184 [000] 1774.275547: 8,7 D R [bash]
> ksoftirqd/0-4 [000] 1774.275580: 8,7 C N 0 [0]
> bash-2184 [000] 1774.275648: 8,7 I R [bash]
> bash-2184 [000] 1774.275653: 8,7 D R [bash]
> ksoftirqd/0-4 [000] 1774.275682: 8,7 C N 0 [0]
> bash-2184 [000] 1774.275739: 8,7 I R [bash]
> bash-2184 [000] 1774.275744: 8,7 D R [bash]
> ksoftirqd/0-4 [000] 1774.275771: 8,7 C N 0 [0]
> bash-2184 [000] 1774.275804: 8,7 I R [bash]
> bash-2184 [000] 1774.275808: 8,7 D R [bash]
> ksoftirqd/0-4 [000] 1774.275836: 8,7 C N 0 [0]
>
> After this patch:
>
> # cat trace
> bash-2263 [000] 366.782149: 8,7 I N 0 (00 ..) [bash]
> bash-2263 [000] 366.782323: 8,7 D N 0 (00 ..) [bash]
> bash-2263 [000] 366.782557: 8,7 I R 8 (25 00 ..) [bash]
> bash-2263 [000] 366.782560: 8,7 D R 8 (25 00 ..) [bash]
> ksoftirqd/0-4 [000] 366.782582: 8,7 C N (25 00 ..) [0]
> bash-2263 [000] 366.782648: 8,7 I R 8 (5a 00 3f 00) [bash]
> bash-2263 [000] 366.782650: 8,7 D R 8 (5a 00 3f 00) [bash]
> ksoftirqd/0-4 [000] 366.782669: 8,7 C N (5a 00 3f 00) [0]
> bash-2263 [000] 366.782710: 8,7 I R 8 (5a 00 08 00) [bash]
> bash-2263 [000] 366.782713: 8,7 D R 8 (5a 00 08 00) [bash]
> ksoftirqd/0-4 [000] 366.782730: 8,7 C N (5a 00 08 00) [0]
> bash-2263 [000] 366.783375: 8,7 I R 36 (5a 00 08 00) [bash]
> bash-2263 [000] 366.783379: 8,7 D R 36 (5a 00 08 00) [bash]
> ksoftirqd/0-4 [000] 366.783404: 8,7 C N (5a 00 08 00) [0]
>
> This is what we do with PC events in user-space blktrace.
>
> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
> ---
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH 2/2] blktrace: fix output of BLK_TC_PC events
2009-04-11 8:15 ` Li Zefan
@ 2009-04-12 13:07 ` Ingo Molnar
2009-04-12 13:10 ` Jens Axboe
0 siblings, 1 reply; 13+ messages in thread
From: Ingo Molnar @ 2009-04-12 13:07 UTC (permalink / raw)
To: Li Zefan
Cc: Jens Axboe, Arnaldo Carvalho de Melo, Steven Rostedt,
Frederic Weisbecker, LKML
* Li Zefan <lizf@cn.fujitsu.com> wrote:
> Hi Ingo,
>
> I would like to ask what's the status of these 2 patches.
>
> Arnaldo acked on them.
They looked good to me - but i'm waiting for an Ack from Jens. Jens
has complained about seeing un-ack-ed patches in the blktrace code,
so i've started serializing any new patches on acks from Jens. The
workflow would be more efficient i suspect if Jens
nominated/declared you and Arnaldo as blktrace co-maintainers too -
most of the patches come from you two.
Ingo
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH 2/2] blktrace: fix output of BLK_TC_PC events
2009-04-12 13:07 ` Ingo Molnar
@ 2009-04-12 13:10 ` Jens Axboe
2009-04-12 13:37 ` Ingo Molnar
2009-04-13 0:40 ` Li Zefan
0 siblings, 2 replies; 13+ messages in thread
From: Jens Axboe @ 2009-04-12 13:10 UTC (permalink / raw)
To: Ingo Molnar
Cc: Li Zefan, Arnaldo Carvalho de Melo, Steven Rostedt,
Frederic Weisbecker, LKML
On Sun, Apr 12 2009, Ingo Molnar wrote:
>
> * Li Zefan <lizf@cn.fujitsu.com> wrote:
>
> > Hi Ingo,
> >
> > I would like to ask what's the status of these 2 patches.
> >
> > Arnaldo acked on them.
>
> They looked good to me - but i'm waiting for an Ack from Jens. Jens
> has complained about seeing un-ack-ed patches in the blktrace code,
> so i've started serializing any new patches on acks from Jens. The
> workflow would be more efficient i suspect if Jens
> nominated/declared you and Arnaldo as blktrace co-maintainers too -
> most of the patches come from you two.
I'd be fine with listing Li Zefan as co-maintainer of the blktrace bits.
He knows what he is doing and is also a user of blktrace, so I think he
would be fine. Li, what do you think?
--
Jens Axboe
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH 2/2] blktrace: fix output of BLK_TC_PC events
2009-04-12 13:10 ` Jens Axboe
@ 2009-04-12 13:37 ` Ingo Molnar
2009-04-13 0:43 ` Li Zefan
2009-04-13 0:40 ` Li Zefan
1 sibling, 1 reply; 13+ messages in thread
From: Ingo Molnar @ 2009-04-12 13:37 UTC (permalink / raw)
To: Jens Axboe
Cc: Li Zefan, Arnaldo Carvalho de Melo, Steven Rostedt,
Frederic Weisbecker, LKML
* Jens Axboe <jens.axboe@oracle.com> wrote:
> On Sun, Apr 12 2009, Ingo Molnar wrote:
> >
> > * Li Zefan <lizf@cn.fujitsu.com> wrote:
> >
> > > Hi Ingo,
> > >
> > > I would like to ask what's the status of these 2 patches.
> > >
> > > Arnaldo acked on them.
> >
> > They looked good to me - but i'm waiting for an Ack from Jens. Jens
> > has complained about seeing un-ack-ed patches in the blktrace code,
> > so i've started serializing any new patches on acks from Jens. The
> > workflow would be more efficient i suspect if Jens
> > nominated/declared you and Arnaldo as blktrace co-maintainers too -
> > most of the patches come from you two.
>
> I'd be fine with listing Li Zefan as co-maintainer of the blktrace
> bits. He knows what he is doing and is also a user of blktrace, so
> I think he would be fine. Li, what do you think?
Cool ... i've also taken this as an implicit approval from you of Li
sending blktrace patches so i have queued the two up.
The next big (and nice!) step would be the blktrace events in
TRACE_EVENT() style. That would integrate the blktrace tracepoints
with all the others, in one coherent framework.
Thanks,
Ingo
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH 2/2] blktrace: fix output of BLK_TC_PC events
2009-04-12 13:37 ` Ingo Molnar
@ 2009-04-13 0:43 ` Li Zefan
0 siblings, 0 replies; 13+ messages in thread
From: Li Zefan @ 2009-04-13 0:43 UTC (permalink / raw)
To: Ingo Molnar
Cc: Jens Axboe, Arnaldo Carvalho de Melo, Steven Rostedt,
Frederic Weisbecker, LKML
Ingo Molnar wrote:
> * Jens Axboe <jens.axboe@oracle.com> wrote:
>
>> On Sun, Apr 12 2009, Ingo Molnar wrote:
>>> * Li Zefan <lizf@cn.fujitsu.com> wrote:
>>>
>>>> Hi Ingo,
>>>>
>>>> I would like to ask what's the status of these 2 patches.
>>>>
>>>> Arnaldo acked on them.
>>> They looked good to me - but i'm waiting for an Ack from Jens. Jens
>>> has complained about seeing un-ack-ed patches in the blktrace code,
>>> so i've started serializing any new patches on acks from Jens. The
>>> workflow would be more efficient i suspect if Jens
>>> nominated/declared you and Arnaldo as blktrace co-maintainers too -
>>> most of the patches come from you two.
>> I'd be fine with listing Li Zefan as co-maintainer of the blktrace
>> bits. He knows what he is doing and is also a user of blktrace, so
>> I think he would be fine. Li, what do you think?
>
> Cool ... i've also taken this as an implicit approval from you of Li
> sending blktrace patches so i have queued the two up.
>
Thanks!
> The next big (and nice!) step would be the blktrace events in
> TRACE_EVENT() style. That would integrate the blktrace tracepoints
> with all the others, in one coherent framework.
>
As I mentioned in another mail thread, this is what we are planning
to do. :)
--
Zefan
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH 2/2] blktrace: fix output of BLK_TC_PC events
2009-04-12 13:10 ` Jens Axboe
2009-04-12 13:37 ` Ingo Molnar
@ 2009-04-13 0:40 ` Li Zefan
1 sibling, 0 replies; 13+ messages in thread
From: Li Zefan @ 2009-04-13 0:40 UTC (permalink / raw)
To: Jens Axboe
Cc: Ingo Molnar, Arnaldo Carvalho de Melo, Steven Rostedt,
Frederic Weisbecker, LKML
Jens Axboe wrote:
> On Sun, Apr 12 2009, Ingo Molnar wrote:
>> * Li Zefan <lizf@cn.fujitsu.com> wrote:
>>
>>> Hi Ingo,
>>>
>>> I would like to ask what's the status of these 2 patches.
>>>
>>> Arnaldo acked on them.
>> They looked good to me - but i'm waiting for an Ack from Jens. Jens
>> has complained about seeing un-ack-ed patches in the blktrace code,
>> so i've started serializing any new patches on acks from Jens. The
>> workflow would be more efficient i suspect if Jens
>> nominated/declared you and Arnaldo as blktrace co-maintainers too -
>> most of the patches come from you two.
>
> I'd be fine with listing Li Zefan as co-maintainer of the blktrace bits.
> He knows what he is doing and is also a user of blktrace, so I think he
> would be fine. Li, what do you think?
>
Thanks. It's fine for me too.
--
Zefan
^ permalink raw reply [flat|nested] 13+ messages in thread
* [tip:tracing/core] blktrace: fix output of BLK_TC_PC events
2009-04-01 8:19 ` [PATCH 2/2] blktrace: fix output of BLK_TC_PC events Li Zefan
2009-04-01 11:00 ` Ingo Molnar
2009-04-11 8:15 ` Li Zefan
@ 2009-04-13 22:22 ` tip-bot for Li Zefan
2 siblings, 0 replies; 13+ messages in thread
From: tip-bot for Li Zefan @ 2009-04-13 22:22 UTC (permalink / raw)
To: linux-tip-commits
Cc: linux-kernel, acme, hpa, mingo, lizf, jens.axboe, fweisbec,
rostedt, tglx, mingo
Commit-ID: 66de7792c02693b49671afe58c771fde3b092fc7
Gitweb: http://git.kernel.org/tip/66de7792c02693b49671afe58c771fde3b092fc7
Author: Li Zefan <lizf@cn.fujitsu.com>
AuthorDate: Wed, 1 Apr 2009 16:19:19 +0800
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Sun, 12 Apr 2009 15:32:46 +0200
blktrace: fix output of BLK_TC_PC events
BLK_TC_PC events should be treated differently with BLK_TC_FS events.
Before this patch:
# echo 1 > /sys/block/sda/sda1/trace/enable
# echo pc > /sys/block/sda/sda1/trace/act_mask
# echo blk > /debugfs/tracing/current_tracer
# (generate some BLK_TC_PC events)
# cat trace
bash-2184 [000] 1774.275413: 8,7 I N [bash]
bash-2184 [000] 1774.275435: 8,7 D N [bash]
bash-2184 [000] 1774.275540: 8,7 I R [bash]
bash-2184 [000] 1774.275547: 8,7 D R [bash]
ksoftirqd/0-4 [000] 1774.275580: 8,7 C N 0 [0]
bash-2184 [000] 1774.275648: 8,7 I R [bash]
bash-2184 [000] 1774.275653: 8,7 D R [bash]
ksoftirqd/0-4 [000] 1774.275682: 8,7 C N 0 [0]
bash-2184 [000] 1774.275739: 8,7 I R [bash]
bash-2184 [000] 1774.275744: 8,7 D R [bash]
ksoftirqd/0-4 [000] 1774.275771: 8,7 C N 0 [0]
bash-2184 [000] 1774.275804: 8,7 I R [bash]
bash-2184 [000] 1774.275808: 8,7 D R [bash]
ksoftirqd/0-4 [000] 1774.275836: 8,7 C N 0 [0]
After this patch:
# cat trace
bash-2263 [000] 366.782149: 8,7 I N 0 (00 ..) [bash]
bash-2263 [000] 366.782323: 8,7 D N 0 (00 ..) [bash]
bash-2263 [000] 366.782557: 8,7 I R 8 (25 00 ..) [bash]
bash-2263 [000] 366.782560: 8,7 D R 8 (25 00 ..) [bash]
ksoftirqd/0-4 [000] 366.782582: 8,7 C N (25 00 ..) [0]
bash-2263 [000] 366.782648: 8,7 I R 8 (5a 00 3f 00) [bash]
bash-2263 [000] 366.782650: 8,7 D R 8 (5a 00 3f 00) [bash]
ksoftirqd/0-4 [000] 366.782669: 8,7 C N (5a 00 3f 00) [0]
bash-2263 [000] 366.782710: 8,7 I R 8 (5a 00 08 00) [bash]
bash-2263 [000] 366.782713: 8,7 D R 8 (5a 00 08 00) [bash]
ksoftirqd/0-4 [000] 366.782730: 8,7 C N (5a 00 08 00) [0]
bash-2263 [000] 366.783375: 8,7 I R 36 (5a 00 08 00) [bash]
bash-2263 [000] 366.783379: 8,7 D R 36 (5a 00 08 00) [bash]
ksoftirqd/0-4 [000] 366.783404: 8,7 C N (5a 00 08 00) [0]
This is what we do with PC events in user-space blktrace.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <49D32387.9040106@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
kernel/trace/blktrace.c | 88 ++++++++++++++++++++++++++++++++++++++++++----
1 files changed, 80 insertions(+), 8 deletions(-)
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index e45e1af..2b98195 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -971,6 +971,16 @@ static inline const void *pdu_start(const struct trace_entry *ent)
return te_blk_io_trace(ent) + 1;
}
+static inline u32 t_action(const struct trace_entry *ent)
+{
+ return te_blk_io_trace(ent)->action;
+}
+
+static inline u32 t_bytes(const struct trace_entry *ent)
+{
+ return te_blk_io_trace(ent)->bytes;
+}
+
static inline u32 t_sec(const struct trace_entry *ent)
{
return te_blk_io_trace(ent)->bytes >> 9;
@@ -1031,25 +1041,87 @@ static int blk_log_action(struct trace_iterator *iter, const char *act)
MAJOR(t->device), MINOR(t->device), act, rwbs);
}
+static int blk_log_dump_pdu(struct trace_seq *s, const struct trace_entry *ent)
+{
+ const char *pdu_buf;
+ int pdu_len;
+ int i, end, ret;
+
+ pdu_buf = pdu_start(ent);
+ pdu_len = te_blk_io_trace(ent)->pdu_len;
+
+ if (!pdu_len)
+ return 1;
+
+ /* find the last zero that needs to be printed */
+ for (end = pdu_len - 1; end >= 0; end--)
+ if (pdu_buf[end])
+ break;
+ end++;
+
+ if (!trace_seq_putc(s, '('))
+ return 0;
+
+ for (i = 0; i < pdu_len; i++) {
+
+ ret = trace_seq_printf(s, "%s%02x",
+ i == 0 ? "" : " ", pdu_buf[i]);
+ if (!ret)
+ return ret;
+
+ /*
+ * stop when the rest is just zeroes and indicate so
+ * with a ".." appended
+ */
+ if (i == end && end != pdu_len - 1)
+ return trace_seq_puts(s, " ..) ");
+ }
+
+ return trace_seq_puts(s, ") ");
+}
+
static int blk_log_generic(struct trace_seq *s, const struct trace_entry *ent)
{
char cmd[TASK_COMM_LEN];
trace_find_cmdline(ent->pid, cmd);
- if (t_sec(ent))
- return trace_seq_printf(s, "%llu + %u [%s]\n",
- t_sector(ent), t_sec(ent), cmd);
- return trace_seq_printf(s, "[%s]\n", cmd);
+ if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) {
+ int ret;
+
+ ret = trace_seq_printf(s, "%u ", t_bytes(ent));
+ if (!ret)
+ return 0;
+ ret = blk_log_dump_pdu(s, ent);
+ if (!ret)
+ return 0;
+ return trace_seq_printf(s, "[%s]\n", cmd);
+ } else {
+ if (t_sec(ent))
+ return trace_seq_printf(s, "%llu + %u [%s]\n",
+ t_sector(ent), t_sec(ent), cmd);
+ return trace_seq_printf(s, "[%s]\n", cmd);
+ }
}
static int blk_log_with_error(struct trace_seq *s,
const struct trace_entry *ent)
{
- if (t_sec(ent))
- return trace_seq_printf(s, "%llu + %u [%d]\n", t_sector(ent),
- t_sec(ent), t_error(ent));
- return trace_seq_printf(s, "%llu [%d]\n", t_sector(ent), t_error(ent));
+ if (t_action(ent) & BLK_TC_ACT(BLK_TC_PC)) {
+ int ret;
+
+ ret = blk_log_dump_pdu(s, ent);
+ if (ret)
+ return trace_seq_printf(s, "[%d]\n", t_error(ent));
+ return 0;
+ } else {
+ if (t_sec(ent))
+ return trace_seq_printf(s, "%llu + %u [%d]\n",
+ t_sector(ent),
+ t_sec(ent), t_error(ent));
+ return trace_seq_printf(s, "%llu [%d]\n",
+ t_sector(ent), t_error(ent));
+ }
}
static int blk_log_remap(struct trace_seq *s, const struct trace_entry *ent)
^ permalink raw reply related [flat|nested] 13+ messages in thread