From: Arnaldo Carvalho de Melo <acme@kernel.org>
To: Adrian Hunter <adrian.hunter@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>,
linux-kernel@vger.kernel.org, David Ahern <dsahern@gmail.com>,
Frederic Weisbecker <fweisbec@gmail.com>,
Jiri Olsa <jolsa@redhat.com>, Namhyung Kim <namhyung@gmail.com>,
Paul Mackerras <paulus@samba.org>,
Stephane Eranian <eranian@google.com>
Subject: Re: [PATCH 05/16] perf tools: Add facility to export data in database-friendly way
Date: Thu, 23 Oct 2014 18:42:49 -0300 [thread overview]
Message-ID: <20141023214249.GP14687@kernel.org> (raw)
In-Reply-To: <1414061124-26830-6-git-send-email-adrian.hunter@intel.com>
Em Thu, Oct 23, 2014 at 01:45:13PM +0300, Adrian Hunter escreveu:
> This patch introduces an abstraction for exporting sample
> data in a database-friendly way. The abstraction does not
> implement the actual output. A subsequent patch takes this
> facility into use for extending the script interface.
>
> The abstraction is needed because static data like symbols,
> dsos, comms etc need to be exported only once. That means
> allocating them a unique identifier and recording it on each
> structure. The member 'db_id' is used for that. 'db_id'
> is just a 64-bit sequence number.
>
> Exporting centres around the db_export__sample() function
> which exports the associated data structures if they have
> not yet been allocated a db_id.
So this ends up bloating all data structures with 8 extra bytes, can't
we use the priv pointer that some of the structures already have for
tooling to put tool specific stuff?
In places like this:
> @@ -25,6 +25,7 @@ struct thread {
> bool dead; /* if set thread has exited */
> struct list_head comm_list;
> int comm_len;
> + u64 db_id;
>
> void *priv;
> struct thread_stack *ts;
Instead we would have:
union {
void *priv;
u64 db_id;
};
Using a unnamed union is all that is needed in struct thread case, I
think, the rest of your patch that deals with 'struct thread' doesn't
need to change and the end impact for other tools that have no use
whatsoever fot this thread->db_id is zero.
Because after all you will end up using some tool to just process
samples, etc, i.e. basically a 'perf report' like tool that instead of
creating hist_entries, etc will end up just populating the
machines ->
machine ->
threads ->
map_groups ->
map ->
dso ->
symbols
Hierarchy, right?
Struct symbol even has a mechanism for reserving space for private use,
that symbol_conf.priv_size + symbol__priv(), so that we don't incur even
in the cost of the priv pointer.
struct perf_evsel already has:
union {
void *priv;
off_t id_offset;
};
Just add db_id there and the rest of your patch that deals with
perf_evsel will not need to be changed and again the impact for tools
that do not use this will be zero.
The other data structures that still don't have a ->priv area can have
one added.
I.e. tool specific bloating of core data structures should be avoided.
Fixing up these things will allow a good chunk of this patchkit to be
processed.
Thanks,
- Arnaldo
> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
> ---
> tools/perf/Makefile.perf | 2 +
> tools/perf/util/comm.h | 1 +
> tools/perf/util/db-export.c | 268 ++++++++++++++++++++++++++++++++++++++++++++
> tools/perf/util/db-export.h | 86 ++++++++++++++
> tools/perf/util/dso.h | 1 +
> tools/perf/util/evsel.h | 1 +
> tools/perf/util/machine.h | 1 +
> tools/perf/util/symbol.h | 1 +
> tools/perf/util/thread.h | 1 +
> 9 files changed, 362 insertions(+)
> create mode 100644 tools/perf/util/db-export.c
> create mode 100644 tools/perf/util/db-export.h
>
> diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
> index 5bbe1ff..9134c93 100644
> --- a/tools/perf/Makefile.perf
> +++ b/tools/perf/Makefile.perf
> @@ -305,6 +305,7 @@ LIB_H += ui/ui.h
> LIB_H += util/data.h
> LIB_H += util/kvm-stat.h
> LIB_H += util/thread-stack.h
> +LIB_H += util/db-export.h
>
> LIB_OBJS += $(OUTPUT)util/abspath.o
> LIB_OBJS += $(OUTPUT)util/alias.o
> @@ -382,6 +383,7 @@ LIB_OBJS += $(OUTPUT)util/data.o
> LIB_OBJS += $(OUTPUT)util/tsc.o
> LIB_OBJS += $(OUTPUT)util/cloexec.o
> LIB_OBJS += $(OUTPUT)util/thread-stack.o
> +LIB_OBJS += $(OUTPUT)util/db-export.o
>
> LIB_OBJS += $(OUTPUT)ui/setup.o
> LIB_OBJS += $(OUTPUT)ui/helpline.o
> diff --git a/tools/perf/util/comm.h b/tools/perf/util/comm.h
> index 51c10ab..99e7021 100644
> --- a/tools/perf/util/comm.h
> +++ b/tools/perf/util/comm.h
> @@ -10,6 +10,7 @@ struct comm_str;
> struct comm {
> struct comm_str *comm_str;
> u64 start;
> + u64 db_id;
> struct list_head list;
> bool exec;
> };
> diff --git a/tools/perf/util/db-export.c b/tools/perf/util/db-export.c
> new file mode 100644
> index 0000000..53d0e75
> --- /dev/null
> +++ b/tools/perf/util/db-export.c
> @@ -0,0 +1,268 @@
> +/*
> + * db-export.c: Support for exporting data suitable for import to a database
> + * Copyright (c) 2014, Intel Corporation.
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms and conditions of the GNU General Public License,
> + * version 2, as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope it will be useful, but WITHOUT
> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
> + * more details.
> + *
> + */
> +
> +#include <errno.h>
> +
> +#include "evsel.h"
> +#include "machine.h"
> +#include "thread.h"
> +#include "comm.h"
> +#include "symbol.h"
> +#include "event.h"
> +#include "db-export.h"
> +
> +int db_export__init(struct db_export *dbe)
> +{
> + memset(dbe, 0, sizeof(struct db_export));
> + return 0;
> +}
> +
> +void db_export__exit(struct db_export *dbe __maybe_unused)
> +{
> +}
> +
> +int db_export__evsel(struct db_export *dbe, struct perf_evsel *evsel)
> +{
> + if (evsel->db_id)
> + return 0;
> +
> + evsel->db_id = ++dbe->evsel_last_db_id;
> +
> + if (dbe->export_evsel)
> + return dbe->export_evsel(dbe, evsel);
> +
> + return 0;
> +}
> +
> +int db_export__machine(struct db_export *dbe, struct machine *machine)
> +{
> + if (machine->db_id)
> + return 0;
> +
> + machine->db_id = ++dbe->machine_last_db_id;
> +
> + if (dbe->export_machine)
> + return dbe->export_machine(dbe, machine);
> +
> + return 0;
> +}
> +
> +int db_export__thread(struct db_export *dbe, struct thread *thread,
> + struct machine *machine, struct comm *comm)
> +{
> + u64 main_thread_db_id = 0;
> + int err;
> +
> + if (thread->db_id)
> + return 0;
> +
> + thread->db_id = ++dbe->thread_last_db_id;
> +
> + if (thread->pid_ != -1) {
> + struct thread *main_thread;
> +
> + if (thread->pid_ == thread->tid) {
> + main_thread = thread;
> + } else {
> + main_thread = machine__findnew_thread(machine,
> + thread->pid_,
> + thread->pid_);
> + if (!main_thread)
> + return -ENOMEM;
> + err = db_export__thread(dbe, main_thread, machine,
> + comm);
> + if (err)
> + return err;
> + if (comm) {
> + err = db_export__comm_thread(dbe, comm, thread);
> + if (err)
> + return err;
> + }
> + }
> + main_thread_db_id = main_thread->db_id;
> + }
> +
> + if (dbe->export_thread)
> + return dbe->export_thread(dbe, thread, main_thread_db_id,
> + machine);
> +
> + return 0;
> +}
> +
> +int db_export__comm(struct db_export *dbe, struct comm *comm,
> + struct thread *main_thread)
> +{
> + int err;
> +
> + if (comm->db_id)
> + return 0;
> +
> + comm->db_id = ++dbe->comm_last_db_id;
> +
> + if (dbe->export_comm) {
> + err = dbe->export_comm(dbe, comm);
> + if (err)
> + return err;
> + }
> +
> + return db_export__comm_thread(dbe, comm, main_thread);
> +}
> +
> +int db_export__comm_thread(struct db_export *dbe, struct comm *comm,
> + struct thread *thread)
> +{
> + u64 db_id;
> +
> + db_id = ++dbe->comm_thread_last_db_id;
> +
> + if (dbe->export_comm_thread)
> + return dbe->export_comm_thread(dbe, db_id, comm, thread);
> +
> + return 0;
> +}
> +
> +int db_export__dso(struct db_export *dbe, struct dso *dso,
> + struct machine *machine)
> +{
> + if (dso->db_id)
> + return 0;
> +
> + dso->db_id = ++dbe->dso_last_db_id;
> +
> + if (dbe->export_dso)
> + return dbe->export_dso(dbe, dso, machine);
> +
> + return 0;
> +}
> +
> +int db_export__symbol(struct db_export *dbe, struct symbol *sym,
> + struct dso *dso)
> +{
> + if (sym->db_id)
> + return 0;
> +
> + sym->db_id = ++dbe->symbol_last_db_id;
> +
> + if (dbe->export_symbol)
> + return dbe->export_symbol(dbe, sym, dso);
> +
> + return 0;
> +}
> +
> +static struct thread *get_main_thread(struct machine *machine,
> + struct thread *thread)
> +{
> + if (thread->pid_ == thread->tid)
> + return thread;
> +
> + if (thread->pid_ == -1)
> + return NULL;
> +
> + return machine__find_thread(machine, thread->pid_, thread->pid_);
> +}
> +
> +static int db_ids_from_al(struct db_export *dbe, struct addr_location *al,
> + u64 *dso_db_id, u64 *sym_db_id, u64 *offset)
> +{
> + int err;
> +
> + if (al->map) {
> + struct dso *dso = al->map->dso;
> +
> + err = db_export__dso(dbe, dso, al->machine);
> + if (err)
> + return err;
> + *dso_db_id = dso->db_id;
> +
> + if (!al->sym) {
> + al->sym = symbol__new(al->addr, 0, 0, "unknown");
> + if (al->sym)
> + symbols__insert(&dso->symbols[al->map->type],
> + al->sym);
> + }
> +
> + if (al->sym) {
> + err = db_export__symbol(dbe, al->sym, dso);
> + if (err)
> + return err;
> + *sym_db_id = al->sym->db_id;
> + *offset = al->addr - al->sym->start;
> + }
> + }
> +
> + return 0;
> +}
> +
> +int db_export__sample(struct db_export *dbe, union perf_event *event,
> + struct perf_sample *sample, struct perf_evsel *evsel,
> + struct thread *thread, struct addr_location *al)
> +{
> + struct export_sample es = {
> + .event = event,
> + .sample = sample,
> + .evsel = evsel,
> + .thread = thread,
> + .al = al,
> + };
> + struct thread *main_thread;
> + struct comm *comm = NULL;
> + int err;
> +
> + err = db_export__evsel(dbe, evsel);
> + if (err)
> + return err;
> +
> + err = db_export__machine(dbe, al->machine);
> + if (err)
> + return err;
> +
> + main_thread = get_main_thread(al->machine, thread);
> + if (main_thread)
> + comm = machine__thread_exec_comm(al->machine, main_thread);
> +
> + err = db_export__thread(dbe, thread, al->machine, comm);
> + if (err)
> + return err;
> +
> + if (comm) {
> + err = db_export__comm(dbe, comm, main_thread);
> + if (err)
> + return err;
> + es.comm_db_id = comm->db_id;
> + }
> +
> + es.db_id = ++dbe->sample_last_db_id;
> +
> + err = db_ids_from_al(dbe, al, &es.dso_db_id, &es.sym_db_id, &es.offset);
> + if (err)
> + return err;
> +
> + if ((evsel->attr.sample_type & PERF_SAMPLE_ADDR) &&
> + sample_addr_correlates_sym(&evsel->attr)) {
> + struct addr_location addr_al;
> +
> + perf_event__preprocess_sample_addr(event, sample, al->machine,
> + thread, &addr_al);
> + err = db_ids_from_al(dbe, &addr_al, &es.addr_dso_db_id,
> + &es.addr_sym_db_id, &es.addr_offset);
> + if (err)
> + return err;
> + }
> +
> + if (dbe->export_sample)
> + return dbe->export_sample(dbe, &es);
> +
> + return 0;
> +}
> diff --git a/tools/perf/util/db-export.h b/tools/perf/util/db-export.h
> new file mode 100644
> index 0000000..b3643e8
> --- /dev/null
> +++ b/tools/perf/util/db-export.h
> @@ -0,0 +1,86 @@
> +/*
> + * db-export.h: Support for exporting data suitable for import to a database
> + * Copyright (c) 2014, Intel Corporation.
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms and conditions of the GNU General Public License,
> + * version 2, as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope it will be useful, but WITHOUT
> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
> + * more details.
> + *
> + */
> +
> +#ifndef __PERF_DB_EXPORT_H
> +#define __PERF_DB_EXPORT_H
> +
> +#include <linux/types.h>
> +
> +struct perf_evsel;
> +struct machine;
> +struct thread;
> +struct comm;
> +struct dso;
> +struct perf_sample;
> +struct addr_location;
> +
> +struct export_sample {
> + union perf_event *event;
> + struct perf_sample *sample;
> + struct perf_evsel *evsel;
> + struct thread *thread;
> + struct addr_location *al;
> + u64 db_id;
> + u64 comm_db_id;
> + u64 dso_db_id;
> + u64 sym_db_id;
> + u64 offset; /* ip offset from symbol start */
> + u64 addr_dso_db_id;
> + u64 addr_sym_db_id;
> + u64 addr_offset; /* addr offset from symbol start */
> +};
> +
> +struct db_export {
> + int (*export_evsel)(struct db_export *dbe, struct perf_evsel *evsel);
> + int (*export_machine)(struct db_export *dbe, struct machine *machine);
> + int (*export_thread)(struct db_export *dbe, struct thread *thread,
> + u64 main_thread_db_id, struct machine *machine);
> + int (*export_comm)(struct db_export *dbe, struct comm *comm);
> + int (*export_comm_thread)(struct db_export *dbe, u64 db_id,
> + struct comm *comm, struct thread *thread);
> + int (*export_dso)(struct db_export *dbe, struct dso *dso,
> + struct machine *machine);
> + int (*export_symbol)(struct db_export *dbe, struct symbol *sym,
> + struct dso *dso);
> + int (*export_sample)(struct db_export *dbe, struct export_sample *es);
> + u64 evsel_last_db_id;
> + u64 machine_last_db_id;
> + u64 thread_last_db_id;
> + u64 comm_last_db_id;
> + u64 comm_thread_last_db_id;
> + u64 dso_last_db_id;
> + u64 symbol_last_db_id;
> + u64 sample_last_db_id;
> +};
> +
> +int db_export__init(struct db_export *dbe);
> +void db_export__exit(struct db_export *dbe);
> +int db_export__evsel(struct db_export *dbe, struct perf_evsel *evsel);
> +int db_export__machine(struct db_export *dbe, struct machine *machine);
> +int db_export__thread(struct db_export *dbe, struct thread *thread,
> + struct machine *machine, struct comm *comm);
> +int db_export__comm(struct db_export *dbe, struct comm *comm,
> + struct thread *main_thread);
> +int db_export__comm_thread(struct db_export *dbe, struct comm *comm,
> + struct thread *thread);
> +int db_export__dso(struct db_export *dbe, struct dso *dso,
> + struct machine *machine);
> +int db_export__symbol(struct db_export *dbe, struct symbol *sym,
> + struct dso *dso);
> +int db_export__sample(struct db_export *dbe, union perf_event *event,
> + struct perf_sample *sample, struct perf_evsel *evsel,
> + struct thread *thread, struct addr_location *al);
> +
> +#endif
> diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
> index acb651a..8463fc3 100644
> --- a/tools/perf/util/dso.h
> +++ b/tools/perf/util/dso.h
> @@ -111,6 +111,7 @@ struct dso {
> enum dso_swap_type needs_swap;
> enum dso_binary_type symtab_type;
> enum dso_binary_type binary_type;
> + u64 db_id;
> u8 adjust_symbols:1;
> u8 has_build_id:1;
> u8 has_srcline:1;
> diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
> index 4861e8c..4777262 100644
> --- a/tools/perf/util/evsel.h
> +++ b/tools/perf/util/evsel.h
> @@ -95,6 +95,7 @@ struct perf_evsel {
> int sample_read;
> struct perf_evsel *leader;
> char *group_name;
> + u64 db_id;
> };
>
> union u64_swap {
> diff --git a/tools/perf/util/machine.h b/tools/perf/util/machine.h
> index 2b651a7..4bc57e5 100644
> --- a/tools/perf/util/machine.h
> +++ b/tools/perf/util/machine.h
> @@ -40,6 +40,7 @@ struct machine {
> u64 kernel_start;
> symbol_filter_t symbol_filter;
> pid_t *current_tid;
> + u64 db_id;
> };
>
> static inline
> diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
> index eb2c19b..6f54ade 100644
> --- a/tools/perf/util/symbol.h
> +++ b/tools/perf/util/symbol.h
> @@ -73,6 +73,7 @@ struct symbol {
> struct rb_node rb_node;
> u64 start;
> u64 end;
> + u64 db_id;
> u16 namelen;
> u8 binding;
> bool ignore;
> diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h
> index a057820..a3ebb21 100644
> --- a/tools/perf/util/thread.h
> +++ b/tools/perf/util/thread.h
> @@ -25,6 +25,7 @@ struct thread {
> bool dead; /* if set thread has exited */
> struct list_head comm_list;
> int comm_len;
> + u64 db_id;
>
> void *priv;
> struct thread_stack *ts;
> --
> 1.9.1
next prev parent reply other threads:[~2014-10-23 21:43 UTC|newest]
Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-10-23 10:45 [PATCH 00/16] perf tools: Intel PT preparation continued Adrian Hunter
2014-10-23 10:45 ` [PATCH 01/16] perf tools: Add id index Adrian Hunter
2014-10-23 21:08 ` Arnaldo Carvalho de Melo
2014-10-24 5:10 ` Namhyung Kim
2014-10-24 7:25 ` Adrian Hunter
2014-10-29 8:55 ` Jiri Olsa
2014-10-23 10:45 ` [PATCH 02/16] perf pmu: Let pmu's with no events show up on perf list Adrian Hunter
2014-10-24 5:15 ` Namhyung Kim
2014-10-24 12:57 ` Arnaldo Carvalho de Melo
2014-10-24 13:03 ` Arnaldo Carvalho de Melo
2014-10-24 13:21 ` Arnaldo Carvalho de Melo
2014-10-24 14:36 ` Adrian Hunter
2014-10-24 14:38 ` Adrian Hunter
2014-10-24 14:45 ` Arnaldo Carvalho de Melo
2014-10-24 15:35 ` Arnaldo Carvalho de Melo
2014-10-30 6:45 ` [tip:perf/core] perf pmu: Let pmu' s " tip-bot for Adrian Hunter
2014-10-23 10:45 ` [PATCH 03/16] perf session: Add perf_session__deliver_synth_event() Adrian Hunter
2014-10-24 5:22 ` Namhyung Kim
2014-10-24 10:41 ` Adrian Hunter
2014-10-23 10:45 ` [PATCH 04/16] perf tools: Add a thread stack for synthesizing call chains Adrian Hunter
2014-10-23 20:51 ` Arnaldo Carvalho de Melo
2014-10-24 8:47 ` Adrian Hunter
2014-10-24 5:41 ` Namhyung Kim
2014-10-29 9:03 ` Jiri Olsa
2014-10-29 9:07 ` Jiri Olsa
2014-10-23 10:45 ` [PATCH 05/16] perf tools: Add facility to export data in database-friendly way Adrian Hunter
2014-10-23 21:42 ` Arnaldo Carvalho de Melo [this message]
2014-10-24 6:02 ` Namhyung Kim
2014-10-24 8:11 ` Adrian Hunter
2014-10-24 10:47 ` Adrian Hunter
2014-10-24 12:26 ` Namhyung Kim
2014-10-24 13:13 ` Adrian Hunter
2014-10-24 14:40 ` Arnaldo Carvalho de Melo
2014-10-24 14:41 ` Arnaldo Carvalho de Melo
2014-10-30 6:46 ` [tip:perf/core] " tip-bot for Adrian Hunter
2014-10-23 10:45 ` [PATCH 06/16] perf tools: Extend Python script interface to export data in a " Adrian Hunter
2014-10-30 6:47 ` [tip:perf/core] perf scripting python: Extend " tip-bot for Adrian Hunter
2014-10-23 10:45 ` [PATCH 07/16] perf tools: Add Python script to export to postgresql Adrian Hunter
2014-10-30 6:47 ` [tip:perf/core] perf script: " tip-bot for Adrian Hunter
2014-10-23 10:45 ` [PATCH 08/16] perf tools: Add branch type to db export Adrian Hunter
2014-10-23 10:45 ` [PATCH 09/16] perf tools: Add branch_type and in_tx to Python export Adrian Hunter
2014-10-23 10:45 ` [PATCH 10/16] perf tools: Enhance the thread stack to output call/return data Adrian Hunter
2014-10-29 13:23 ` Jiri Olsa
2014-10-29 14:02 ` Arnaldo Carvalho de Melo
2014-10-23 10:45 ` [PATCH 11/16] perf tools: Add call information to the database export API Adrian Hunter
2014-10-23 10:45 ` [PATCH 12/16] perf tools: Add call information to Python export Adrian Hunter
2014-10-23 10:45 ` [PATCH 13/16] perf tools: Defer export of comms that were not 'set' Adrian Hunter
2014-10-23 10:45 ` [PATCH 14/16] perf tools: Build programs to copy 32-bit compatibility VDSOs Adrian Hunter
2014-10-30 6:45 ` [tip:perf/core] perf tools: Build programs to copy 32-bit compatibility tip-bot for Adrian Hunter
2014-10-23 10:45 ` [PATCH 15/16] perf tools: Add support for 32-bit compatibility VDSOs Adrian Hunter
2014-10-30 6:45 ` [tip:perf/core] " tip-bot for Adrian Hunter
2014-10-23 10:45 ` [PATCH 16/16] perf tools: Do not attempt to run perf-read-vdso32 if it wasn't built Adrian Hunter
2014-10-30 6:46 ` [tip:perf/core] " tip-bot for Adrian Hunter
2014-10-23 21:11 ` [PATCH 00/16] perf tools: Intel PT preparation continued Arnaldo Carvalho de Melo
2014-10-23 23:43 ` Arnaldo Carvalho de Melo
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