Re: [PATCH 2/6] perf tools: Introduce struct perf_log

Arnaldo Carvalho de Melo
2013-12-19T13:28:14Z

Em Thu, Dec 19, 2013 at 04:00:07PM +0900, Namhyung Kim escreveu:
> From: Namhyung Kim <namhyung.kim@lge.com>
>
> Add new functions to save error messages in a temp file. It'll be
> used by some UI front-ends to see the messages.

Do we really have to grow a logging facility like this? Can't we somehow
openlog/syslog/closelog? Just a first gut reaction, continuing to read
the series...

- Arnaldo

> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
> ---
> tools/perf/Makefile.perf | 1 +
> tools/perf/perf.c | 3 ++
> tools/perf/util/debug.h | 15 +++++++
> tools/perf/util/log.c | 105 +++++++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 124 insertions(+)
> create mode 100644 tools/perf/util/log.c
>
> diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
> index 97a2145e4cc6..ec8184014a76 100644
> --- a/tools/perf/Makefile.perf
> +++ b/tools/perf/Makefile.perf
> @@ -372,6 +372,7 @@ LIB_OBJS += $(OUTPUT)util/stat.o
> LIB_OBJS += $(OUTPUT)util/record.o
> LIB_OBJS += $(OUTPUT)util/srcline.o
> LIB_OBJS += $(OUTPUT)util/data.o
> +LIB_OBJS += $(OUTPUT)util/log.o
>
> LIB_OBJS += $(OUTPUT)ui/setup.o
> LIB_OBJS += $(OUTPUT)ui/helpline.o
> diff --git a/tools/perf/perf.c b/tools/perf/perf.c
> index 431798a4110d..bdf7bd8e4394 100644
> --- a/tools/perf/perf.c
> +++ b/tools/perf/perf.c
> @@ -10,6 +10,7 @@
>
> #include "util/exec_cmd.h"
> #include "util/cache.h"
> +#include "util/debug.h"
> #include "util/quote.h"
> #include "util/run-command.h"
> #include "util/parse-events.h"
> @@ -524,6 +525,7 @@ int main(int argc, const char **argv)
> */
> pthread__block_sigwinch();
>
> + perf_log_init();
> while (1) {
> static int done_help;
> int was_alias = run_argv(&argc, &argv);
> @@ -543,6 +545,7 @@ int main(int argc, const char **argv)
> } else
> break;
> }
> + perf_log_exit();
>
> fprintf(stderr, "Failed to run command '%s': %s\n",
> cmd, strerror(errno));
> diff --git a/tools/perf/util/debug.h b/tools/perf/util/debug.h
> index 443694c36b03..ea160abc2ae0 100644
> --- a/tools/perf/util/debug.h
> +++ b/tools/perf/util/debug.h
> @@ -19,4 +19,19 @@ int ui__warning(const char *format, ...) __attribute__((format(printf, 1, 2)));
>
> void pr_stat(const char *fmt, ...);
>
> +struct perf_log {
> + FILE *fp;
> + off_t *linemap;
> + u32 lines;
> + u32 nr_alloc;
> + bool seen_newline;
> +};
> +
> +extern struct perf_log perf_log;
> +
> +int perf_log_init(void);
> +int perf_log_exit(void);
> +void perf_log_add(const char *msg);
> +void perf_log_addv(const char *fmt, va_list ap);
> +
> #endif /* __PERF_DEBUG_H */
> diff --git a/tools/perf/util/log.c b/tools/perf/util/log.c
> new file mode 100644
> index 000000000000..4a34bed2af44
> --- /dev/null
> +++ b/tools/perf/util/log.c
> @@ -0,0 +1,105 @@
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include "util/debug.h"
> +
> +#define LINEMAP_GROW 128
> +
> +struct perf_log perf_log = {
> + .seen_newline = true,
> +};
> +
> +int perf_log_init(void)
> +{
> + FILE *fp;
> + char name[] = "/tmp/perf-tui-log-XXXXXX";
> + int fd = mkstemp(name);
> +
> + if (fd < 0)
> + return -1;
> +
> + fp = fdopen(fd, "r+");
> + if (fp == NULL) {
> + close(fd);
> + return -1;
> + }
> +
> + perf_log.fp = fp;
> +
> + return 0;
> +}
> +
> +int perf_log_exit(void)
> +{
> + FILE *fp = perf_log.fp;
> + if (fp)
> + fclose(fp);
> +
> + free(perf_log.linemap);
> +
> + perf_log.fp = NULL;
> + perf_log.linemap = NULL;
> + return 0;
> +}
> +
> +static int grow_linemap(struct perf_log *log)
> +{
> + off_t *newmap;
> + int newsize = log->nr_alloc + LINEMAP_GROW;
> +
> + newmap = realloc(log->linemap, newsize * sizeof(*log->linemap));
> + if (newmap == NULL)
> + return -1;
> +
> + log->nr_alloc = newsize;
> + log->linemap = newmap;
> + return 0;
> +}
> +
> +static int __add_to_linemap(struct perf_log *log, off_t index)
> +{
> + if (log->lines == log->nr_alloc)
> + if (grow_linemap(log) < 0)
> + return -1;
> +
> + log->linemap[log->lines++] = index;
> + return 0;
> +}
> +
> +static void add_to_linemap(struct perf_log *log, const char *msg, off_t base)
> +{
> + const char *pos;
> +
> + if (strlen(msg) == 0)
> + return;
> +
> + if (log->seen_newline) {
> + if (__add_to_linemap(log, base) < 0)
> + return;
> + }
> +
> + if ((pos = strchr(msg, '\n')) != NULL) {
> + log->seen_newline = true;
> + pos++;
> + add_to_linemap(log, pos, base + (pos - msg));
> + } else {
> + log->seen_newline = false;
> + }
> +}
> +
> +void perf_log_add(const char *msg)
> +{
> + FILE *fp = perf_log.fp;
> + off_t offset = ftello(fp);
> +
> + add_to_linemap(&perf_log, msg, offset);
> +
> + fwrite(msg, 1, strlen(msg), fp);
> +}
> +
> +void perf_log_addv(const char *fmt, va_list ap)
> +{
> + char buf[4096];
> +
> + vsnprintf(buf, sizeof(buf), fmt, ap);
> + perf_log_add(buf);
> +}
> --
> 1.7.11.7