Re: [PATCH 08/11] perf tools: Add perf_exe() helper to find perf binary

[Arnaldo Carvalho de Melo]

Em Mon, Feb 25, 2019 at 01:56:22PM +0100, Jiri Olsa escreveu:
> On Sun, Feb 24, 2019 at 07:37:19AM -0800, Andi Kleen wrote:
> > From: Andi Kleen 
> > 
> > Also convert one existing user.
> > 
> > Signed-off-by: Andi Kleen 
> 
> Acked-by: Jiri Olsa 

Applied.

- Arnaldo

Re: [PATCH 08/11] perf tools: Add perf_exe() helper to find perf binary

[Jiri Olsa]

On Sun, Feb 24, 2019 at 07:37:19AM -0800, Andi Kleen wrote:
> From: Andi Kleen 
> 
> Also convert one existing user.
> 
> Signed-off-by: Andi Kleen 

Acked-by: Jiri Olsa 

thanks,
jirka

> ---
>  tools/perf/util/header.c | 12 +++-
>  tools/perf/util/util.c   | 10 ++
>  tools/perf/util/util.h   |  2 ++
>  3 files changed, 15 insertions(+), 9 deletions(-)
> 
> diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
> index 61ce197c5362..2f290a0343d4 100644
> --- a/tools/perf/util/header.c
> +++ b/tools/perf/util/header.c
> @@ -526,17 +526,11 @@ static int write_event_desc(struct feat_fd *ff,
>  static int write_cmdline(struct feat_fd *ff,
>struct perf_evlist *evlist __maybe_unused)
>  {
> - char buf[MAXPATHLEN];
> - u32 n;
> - int i, ret;
> + char pbuf[MAXPATHLEN], *buf;
> + int i, ret, n;
>  
>   /* actual path to perf binary */
> - ret = readlink("/proc/self/exe", buf, sizeof(buf) - 1);
> - if (ret <= 0)
> - return -1;
> -
> - /* readlink() does not add null termination */
> - buf[ret] = '\0';
> + buf = perf_exe(pbuf, MAXPATHLEN);
>  
>   /* account for binary path */
>   n = perf_env.nr_cmdline + 1;
> diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c
> index 320b0fef249a..dd693e018aef 100644
> --- a/tools/perf/util/util.c
> +++ b/tools/perf/util/util.c
> @@ -507,3 +507,13 @@ const char *perf_tip(const char *dirpath)
>  
>   return tip;
>  }
> +
> +char *perf_exe(char *buf, int len)
> +{
> + int n = readlink("/proc/self/exe", buf, len);
> + if (n > 0) {
> + buf[n] = 0;
> + return buf;
> + }
> + return strcpy(buf, "perf");
> +}
> diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
> index ece040b799f6..dc2a99ad5c96 100644
> --- a/tools/perf/util/util.h
> +++ b/tools/perf/util/util.h
> @@ -76,6 +76,8 @@ extern bool perf_singlethreaded;
>  void perf_set_singlethreaded(void);
>  void perf_set_multithreaded(void);
>  
> +char *perf_exe(char *buf, int len);
> +
>  #ifndef O_CLOEXEC
>  #ifdef __sparc__
>  #define O_CLOEXEC  0x40
> -- 
> 2.17.2
> 

[PATCH 08/11] perf tools: Add perf_exe() helper to find perf binary

[Andi Kleen]

From: Andi Kleen 

Also convert one existing user.

Signed-off-by: Andi Kleen 
---
 tools/perf/util/header.c | 12 +++-
 tools/perf/util/util.c   | 10 ++
 tools/perf/util/util.h   |  2 ++
 3 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 61ce197c5362..2f290a0343d4 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -526,17 +526,11 @@ static int write_event_desc(struct feat_fd *ff,
 static int write_cmdline(struct feat_fd *ff,
 struct perf_evlist *evlist __maybe_unused)
 {
-   char buf[MAXPATHLEN];
-   u32 n;
-   int i, ret;
+   char pbuf[MAXPATHLEN], *buf;
+   int i, ret, n;
 
/* actual path to perf binary */
-   ret = readlink("/proc/self/exe", buf, sizeof(buf) - 1);
-   if (ret <= 0)
-   return -1;
-
-   /* readlink() does not add null termination */
-   buf[ret] = '\0';
+   buf = perf_exe(pbuf, MAXPATHLEN);
 
/* account for binary path */
n = perf_env.nr_cmdline + 1;
diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c
index 320b0fef249a..dd693e018aef 100644
--- a/tools/perf/util/util.c
+++ b/tools/perf/util/util.c
@@ -507,3 +507,13 @@ const char *perf_tip(const char *dirpath)
 
return tip;
 }
+
+char *perf_exe(char *buf, int len)
+{
+   int n = readlink("/proc/self/exe", buf, len);
+   if (n > 0) {
+   buf[n] = 0;
+   return buf;
+   }
+   return strcpy(buf, "perf");
+}
diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index ece040b799f6..dc2a99ad5c96 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -76,6 +76,8 @@ extern bool perf_singlethreaded;
 void perf_set_singlethreaded(void);
 void perf_set_multithreaded(void);
 
+char *perf_exe(char *buf, int len);
+
 #ifndef O_CLOEXEC
 #ifdef __sparc__
 #define O_CLOEXEC  0x40
-- 
2.17.2