[7/7] perf tools: Remove prot field in mmap param

Message ID 20171113013809.212417-8-wangnan0@huawei.com
State New
Headers show
Series
  • perf tools: Clarify overwrite and backward, bugfix
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Commit Message

Wang Nan Nov. 13, 2017, 1:38 a.m.
After removing the concept of 'overwrite' in code level, now the
prot is determinated by write_backward. There's no need to pass
prot from perf_evlist__mmap_ex().

Signed-off-by: Wang Nan <wangnan0@huawei.com>

---
 tools/perf/util/evlist.c | 17 ++++++-----------
 tools/perf/util/mmap.c   |  4 ++--
 tools/perf/util/mmap.h   |  4 ++--
 3 files changed, 10 insertions(+), 15 deletions(-)

-- 
2.10.1

Comments

Jiri Olsa Nov. 13, 2017, 11:52 a.m. | #1
On Mon, Nov 13, 2017 at 01:38:09AM +0000, Wang Nan wrote:
> After removing the concept of 'overwrite' in code level, now the

> prot is determinated by write_backward. There's no need to pass

> prot from perf_evlist__mmap_ex().

> 

> Signed-off-by: Wang Nan <wangnan0@huawei.com>

> ---

>  tools/perf/util/evlist.c | 17 ++++++-----------

>  tools/perf/util/mmap.c   |  4 ++--

>  tools/perf/util/mmap.h   |  4 ++--

>  3 files changed, 10 insertions(+), 15 deletions(-)

> 

> diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c

> index 4948d3d..0d713e0 100644

> --- a/tools/perf/util/evlist.c

> +++ b/tools/perf/util/evlist.c

> @@ -799,28 +799,23 @@ perf_evlist__should_poll(struct perf_evlist *evlist __maybe_unused,

>  }

>  

>  static int perf_evlist__mmap_per_evsel(struct perf_evlist *evlist, int idx,

> -				       struct mmap_params *_mp, int cpu_idx,

> +				       struct mmap_params *mp, int cpu_idx,

>  				       int thread, int *_output, int *_output_backward)

>  {

>  	struct perf_evsel *evsel;

>  	int revent;

>  	int evlist_cpu = cpu_map__cpu(evlist->cpus, cpu_idx);

> -	struct mmap_params *mp;

>  

>  	evlist__for_each_entry(evlist, evsel) {

>  		struct perf_mmap *maps = evlist->mmap;

> -		struct mmap_params rdonly_mp;

>  		int *output = _output;

>  		int fd;

>  		int cpu;

> +		int prot = PROT_READ;


can't you set the PROT_READ in struct mmap_params *mp as its default value?

		mp->prot = PROT_READ;

>  

> -		mp = _mp;

>  		if (evsel->attr.write_backward) {

>  			output = _output_backward;

>  			maps = evlist->backward_mmap;

> -			rdonly_mp = *_mp;

> -			rdonly_mp.prot &= ~PROT_WRITE;

> -			mp = &rdonly_mp;

>  

>  			if (!maps) {

>  				maps = perf_evlist__alloc_mmap(evlist);

> @@ -830,6 +825,8 @@ static int perf_evlist__mmap_per_evsel(struct perf_evlist *evlist, int idx,

>  				if (evlist->bkw_mmap_state == BKW_MMAP_NOTREADY)

>  					perf_evlist__toggle_bkw_mmap(evlist, BKW_MMAP_RUNNING);

>  			}

> +		} else {

> +			prot |= PROT_WRITE;

>  		}

>  

>  		if (evsel->system_wide && thread)

> @@ -844,7 +841,7 @@ static int perf_evlist__mmap_per_evsel(struct perf_evlist *evlist, int idx,

>  		if (*output == -1) {

>  			*output = fd;

>  

> -			if (perf_mmap__mmap(&maps[idx], mp, *output)  < 0)

> +			if (perf_mmap__mmap(&maps[idx], mp, prot, *output)  < 0)


so there's no need for the extra 'prot' param in here

jirka
Jiri Olsa Nov. 13, 2017, 11:52 a.m. | #2
On Mon, Nov 13, 2017 at 01:38:09AM +0000, Wang Nan wrote:
> After removing the concept of 'overwrite' in code level, now the

> prot is determinated by write_backward. There's no need to pass

> prot from perf_evlist__mmap_ex().

> 

> Signed-off-by: Wang Nan <wangnan0@huawei.com>

> ---

>  tools/perf/util/evlist.c | 17 ++++++-----------

>  tools/perf/util/mmap.c   |  4 ++--

>  tools/perf/util/mmap.h   |  4 ++--

>  3 files changed, 10 insertions(+), 15 deletions(-)

> 

> diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c

> index 4948d3d..0d713e0 100644

> --- a/tools/perf/util/evlist.c

> +++ b/tools/perf/util/evlist.c

> @@ -799,28 +799,23 @@ perf_evlist__should_poll(struct perf_evlist *evlist __maybe_unused,

>  }

>  

>  static int perf_evlist__mmap_per_evsel(struct perf_evlist *evlist, int idx,

> -				       struct mmap_params *_mp, int cpu_idx,

> +				       struct mmap_params *mp, int cpu_idx,

>  				       int thread, int *_output, int *_output_backward)

>  {

>  	struct perf_evsel *evsel;

>  	int revent;

>  	int evlist_cpu = cpu_map__cpu(evlist->cpus, cpu_idx);

> -	struct mmap_params *mp;

>  

>  	evlist__for_each_entry(evlist, evsel) {

>  		struct perf_mmap *maps = evlist->mmap;

> -		struct mmap_params rdonly_mp;

>  		int *output = _output;

>  		int fd;

>  		int cpu;

> +		int prot = PROT_READ;

>  

> -		mp = _mp;

>  		if (evsel->attr.write_backward) {

>  			output = _output_backward;

>  			maps = evlist->backward_mmap;

> -			rdonly_mp = *_mp;

> -			rdonly_mp.prot &= ~PROT_WRITE;

> -			mp = &rdonly_mp;


I dont think we need the first patch, you're reverting it in here

jirka

Patch

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 4948d3d..0d713e0 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -799,28 +799,23 @@  perf_evlist__should_poll(struct perf_evlist *evlist __maybe_unused,
 }
 
 static int perf_evlist__mmap_per_evsel(struct perf_evlist *evlist, int idx,
-				       struct mmap_params *_mp, int cpu_idx,
+				       struct mmap_params *mp, int cpu_idx,
 				       int thread, int *_output, int *_output_backward)
 {
 	struct perf_evsel *evsel;
 	int revent;
 	int evlist_cpu = cpu_map__cpu(evlist->cpus, cpu_idx);
-	struct mmap_params *mp;
 
 	evlist__for_each_entry(evlist, evsel) {
 		struct perf_mmap *maps = evlist->mmap;
-		struct mmap_params rdonly_mp;
 		int *output = _output;
 		int fd;
 		int cpu;
+		int prot = PROT_READ;
 
-		mp = _mp;
 		if (evsel->attr.write_backward) {
 			output = _output_backward;
 			maps = evlist->backward_mmap;
-			rdonly_mp = *_mp;
-			rdonly_mp.prot &= ~PROT_WRITE;
-			mp = &rdonly_mp;
 
 			if (!maps) {
 				maps = perf_evlist__alloc_mmap(evlist);
@@ -830,6 +825,8 @@  static int perf_evlist__mmap_per_evsel(struct perf_evlist *evlist, int idx,
 				if (evlist->bkw_mmap_state == BKW_MMAP_NOTREADY)
 					perf_evlist__toggle_bkw_mmap(evlist, BKW_MMAP_RUNNING);
 			}
+		} else {
+			prot |= PROT_WRITE;
 		}
 
 		if (evsel->system_wide && thread)
@@ -844,7 +841,7 @@  static int perf_evlist__mmap_per_evsel(struct perf_evlist *evlist, int idx,
 		if (*output == -1) {
 			*output = fd;
 
-			if (perf_mmap__mmap(&maps[idx], mp, *output)  < 0)
+			if (perf_mmap__mmap(&maps[idx], mp, prot, *output)  < 0)
 				return -1;
 		} else {
 			if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, *output) != 0)
@@ -1064,9 +1061,7 @@  int perf_evlist__mmap_ex(struct perf_evlist *evlist, unsigned int pages,
 	struct perf_evsel *evsel;
 	const struct cpu_map *cpus = evlist->cpus;
 	const struct thread_map *threads = evlist->threads;
-	struct mmap_params mp = {
-		.prot = PROT_READ | PROT_WRITE,
-	};
+	struct mmap_params mp;
 
 	if (!evlist->mmap)
 		evlist->mmap = perf_evlist__alloc_mmap(evlist);
diff --git a/tools/perf/util/mmap.c b/tools/perf/util/mmap.c
index 703ed41..40e91a0 100644
--- a/tools/perf/util/mmap.c
+++ b/tools/perf/util/mmap.c
@@ -219,7 +219,7 @@  void perf_mmap__munmap(struct perf_mmap *map)
 	auxtrace_mmap__munmap(&map->auxtrace_mmap);
 }
 
-int perf_mmap__mmap(struct perf_mmap *map, struct mmap_params *mp, int fd)
+int perf_mmap__mmap(struct perf_mmap *map, struct mmap_params *mp, int prot, int fd)
 {
 	/*
 	 * The last one will be done at perf_evlist__mmap_consume(), so that we
@@ -237,7 +237,7 @@  int perf_mmap__mmap(struct perf_mmap *map, struct mmap_params *mp, int fd)
 	refcount_set(&map->refcnt, 2);
 	map->prev = 0;
 	map->mask = mp->mask;
-	map->base = mmap(NULL, perf_mmap__mmap_len(map), mp->prot,
+	map->base = mmap(NULL, perf_mmap__mmap_len(map), prot,
 			 MAP_SHARED, fd, 0);
 	if (map->base == MAP_FAILED) {
 		pr_debug2("failed to mmap perf event ring buffer, error %d\n",
diff --git a/tools/perf/util/mmap.h b/tools/perf/util/mmap.h
index 2c3d291..1f6fcc6 100644
--- a/tools/perf/util/mmap.h
+++ b/tools/perf/util/mmap.h
@@ -53,11 +53,11 @@  enum bkw_mmap_state {
 };
 
 struct mmap_params {
-	int			    prot, mask;
+	int			    mask;
 	struct auxtrace_mmap_params auxtrace_mp;
 };
 
-int perf_mmap__mmap(struct perf_mmap *map, struct mmap_params *mp, int fd);
+int perf_mmap__mmap(struct perf_mmap *map, struct mmap_params *mp, int prot, int fd);
 void perf_mmap__munmap(struct perf_mmap *map);
 
 void perf_mmap__get(struct perf_mmap *map);