| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Wed, 4 Feb 2009 23:22:10 -0200
From: Arnaldo Carvalho de Melo <acme@...hat.com>
To: Frederic Weisbecker <fweisbec@...il.com>
Cc: Steven Rostedt <rostedt@...dmis.org>, Ingo Molnar <mingo@...e.hu>,
Jens Axboe <jens.axboe@...cle.com>,
Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH tip 1/1] trace: assign defaults at register_ftrace_event
Em Thu, Feb 05, 2009 at 12:41:51AM +0100, Frederic Weisbecker escreveu:
> On Wed, Feb 04, 2009 at 08:16:39PM -0200, Arnaldo Carvalho de Melo wrote:
> > Impact: simplification of tracers
> >
> > As all tracers are doing this we might as well do it in
> > register_ftrace_event and save one branch each time we call these
> > callbacks.
> >
> > Cc: Ingo Molnar <mingo@...e.hu>
> > Cc: Frédéric Weisbecker <fweisbec@...il.com>
> > Cc: Jens Axboe <jens.axboe@...cle.com>
> > Signed-off-by: Arnaldo Carvalho de Melo <acme@...hat.com>
> > ---
> > block/blktrace.c | 2 --
> > kernel/trace/trace.c | 13 +++++--------
> > kernel/trace/trace_branch.c | 3 ---
> > kernel/trace/trace_output.c | 13 +++++++++++--
> > 4 files changed, 16 insertions(+), 15 deletions(-)
> >
> > diff --git a/block/blktrace.c b/block/blktrace.c
> > index c7698d1..1ebd068 100644
> > --- a/block/blktrace.c
> > +++ b/block/blktrace.c
> > @@ -1243,8 +1243,6 @@ static struct trace_event trace_blk_event = {
> > .type = TRACE_BLK,
> > .trace = blk_trace_event_print,
> > .latency_trace = blk_trace_event_print,
> > - .raw = trace_nop_print,
> > - .hex = trace_nop_print,
> > .binary = blk_trace_event_print_binary,
> > };
> >
> > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
> > index fd51cf0..a5e4c0a 100644
> > --- a/kernel/trace/trace.c
> > +++ b/kernel/trace/trace.c
> > @@ -1412,7 +1412,7 @@ static enum print_line_t print_lat_fmt(struct trace_iterator *iter)
> > goto partial;
> > }
> >
> > - if (event && event->latency_trace)
> > + if (event)
> > return event->latency_trace(iter, sym_flags);
> >
> > if (!trace_seq_printf(s, "Unknown type %d\n", entry->type))
> > @@ -1441,7 +1441,7 @@ static enum print_line_t print_trace_fmt(struct trace_iterator *iter)
> > goto partial;
> > }
> >
> > - if (event && event->trace)
> > + if (event)
> > return event->trace(iter, sym_flags);
> >
> > if (!trace_seq_printf(s, "Unknown type %d\n", entry->type))
> > @@ -1467,7 +1467,7 @@ static enum print_line_t print_raw_fmt(struct trace_iterator *iter)
> > }
> >
> > event = ftrace_find_event(entry->type);
> > - if (event && event->raw)
> > + if (event)
> > return event->raw(iter, 0);
> >
> > if (!trace_seq_printf(s, "%d ?\n", entry->type))
> > @@ -1494,7 +1494,7 @@ static enum print_line_t print_hex_fmt(struct trace_iterator *iter)
> > }
> >
> > event = ftrace_find_event(entry->type);
> > - if (event && event->hex) {
> > + if (event) {
> > enum print_line_t ret = event->hex(iter, 0);
> > if (ret != TRACE_TYPE_HANDLED)
> > return ret;
> > @@ -1536,10 +1536,7 @@ static enum print_line_t print_bin_fmt(struct trace_iterator *iter)
> > }
> >
> > event = ftrace_find_event(entry->type);
> > - if (event && event->binary)
> > - return event->binary(iter, 0);
> > -
> > - return TRACE_TYPE_HANDLED;
> > + return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED;
> > }
> >
> > static int trace_empty(struct trace_iterator *iter)
> > diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c
> > index 7ac72a4..297deb2 100644
> > --- a/kernel/trace/trace_branch.c
> > +++ b/kernel/trace/trace_branch.c
> > @@ -182,9 +182,6 @@ static struct trace_event trace_branch_event = {
> > .type = TRACE_BRANCH,
> > .trace = trace_branch_print,
> > .latency_trace = trace_branch_print,
> > - .raw = trace_nop_print,
> > - .hex = trace_nop_print,
> > - .binary = trace_nop_print,
> > };
> >
> > static struct tracer branch_trace __read_mostly =
> > diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
> > index b7380ee..b6e99af 100644
> > --- a/kernel/trace/trace_output.c
> > +++ b/kernel/trace/trace_output.c
> > @@ -435,6 +435,17 @@ int register_ftrace_event(struct trace_event *event)
> > if (ftrace_find_event(event->type))
> > goto out;
> >
> > + if (event->trace == NULL)
> > + event->trace = trace_nop_print;
> > + if (event->latency_trace == NULL)
> > + event->latency_trace = trace_nop_print;
> > + if (event->raw == NULL)
> > + event->raw = trace_nop_print;
> > + if (event->hex == NULL)
> > + event->hex = trace_nop_print;
> > + if (event->binary == NULL)
> > + event->binary = trace_nop_print;
> > +
> > key = event->type & (EVENT_HASHSIZE - 1);
> >
> > hlist_add_head_rcu(&event->node, &event_hash[key]);
> > @@ -874,8 +885,6 @@ static struct trace_event trace_print_event = {
> > .trace = trace_print_print,
> > .latency_trace = trace_print_print,
> > .raw = trace_print_raw,
> > - .hex = trace_nop_print,
> > - .binary = trace_nop_print,
> > };
> >
> > static struct trace_event *events[] __initdata = {
> > --
> > 1.6.0.6
> >
>
>
> Nice! This avoids one branch for each entry printed.
Is that an Acked-by in response to that CC? :-)
- Arnaldo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists