[PATCH 0/4] perf header: Save and reuse feature information in header (v3)

[PATCH 0/4] perf header: Save and reuse feature information in header (v3)

[Namhyung Kim]

Hi,

Currently the perf header information is used only at initial setup
time and discarded.  If it's saved we could reuse the information for
various purpose in the future.

Thanks,
Namhyung


v2 -> v3:
 * patch 1-3 in v2 merged into tip
 * rebased on current acme/perf/core

v1 -> v2:
 * not touch EVENT_DESC feature handling
 * split out struct perf_header_info
 * simplify multi-string handling
 * add some cleanup patches


Namhyung Kim (4):
  perf header: Add struct perf_header_info
  perf header: Add ->process callbacks to most of features
  perf header: Use pre-processed header info when printing
  perf header: Remove unused @feat arg from ->process callback

 tools/perf/util/header.c | 547 +++++++++++++++++++++++++++++++++--------------
 tools/perf/util/header.h |  24 +++
 2 files changed, 408 insertions(+), 163 deletions(-)

-- 
1.7.11.4

[PATCH 1/4] perf header: Add struct perf_header_info

[Namhyung Kim]

From: Namhyung Kim <namhyung.kim@lge.com>

The struct perf_header_info will preserve environment information at
the time of perf record.  It can be accessed anytime after parsing a
perf.data file if needed.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/util/header.h | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/tools/perf/util/header.h b/tools/perf/util/header.h
index 209dad4fee2b..30e92cc714f1 100644
--- a/tools/perf/util/header.h
+++ b/tools/perf/util/header.h
@@ -58,6 +58,29 @@ struct perf_header;
 int perf_file_header__read(struct perf_file_header *header,
 			   struct perf_header *ph, int fd);
 
+struct perf_header_info {
+	char			*hostname;
+	char			*os_release;
+	char			*version;
+	char			*arch;
+	int			nr_cpus_online;
+	int			nr_cpus_avail;
+	char			*cpu_desc;
+	char			*cpuid;
+	unsigned long long	total_mem;
+
+	int			nr_cmdline;
+	char			*cmdline;
+	int			nr_sibling_cores;
+	char			*sibling_cores;
+	int			nr_sibling_threads;
+	char			*sibling_threads;
+	int			nr_numa_nodes;
+	char			*numa_nodes;
+	int			nr_pmu_mappings;
+	char			*pmu_mappings;
+};
+
 struct perf_header {
 	int			frozen;
 	bool			needs_swap;
@@ -67,6 +90,7 @@ struct perf_header {
 	u64			event_offset;
 	u64			event_size;
 	DECLARE_BITMAP(adds_features, HEADER_FEAT_BITS);
+	struct perf_header_info info;
 };
 
 struct perf_evlist;
-- 
1.7.11.4

[PATCH 2/4] perf header: Add ->process callbacks to most of features

[Namhyung Kim]

>From now on each feature information is processed and saved in perf
header so that it can be used wherever needed.  The BRANCH_STACK
feature is an exception since it needs nothing to be done.

Cc: Stephane Eranian <eranian@google.com>
Cc: Robert Richter <robert.richter@amd.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/util/header.c | 318 +++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 307 insertions(+), 11 deletions(-)

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index acbf6336199e..fd29d42dedbe 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -22,6 +22,7 @@
 #include "cpumap.h"
 #include "pmu.h"
 #include "vdso.h"
+#include "strbuf.h"
 
 static bool no_buildid_cache = false;
 
@@ -1673,6 +1674,99 @@ static int process_build_id(struct perf_file_section *section,
 	return 0;
 }
 
+static int process_hostname(struct perf_file_section *section __unused,
+			    struct perf_header *ph,
+			    int feat __unused, int fd, void *data __used)
+{
+	ph->info.hostname = do_read_string(fd, ph);
+	return ph->info.hostname ? 0 : -ENOMEM;
+}
+
+static int process_osrelease(struct perf_file_section *section __unused,
+			     struct perf_header *ph,
+			     int feat __unused, int fd, void *data __used)
+{
+	ph->info.os_release = do_read_string(fd, ph);
+	return ph->info.os_release ? 0 : -ENOMEM;
+}
+
+static int process_version(struct perf_file_section *section __unused,
+			   struct perf_header *ph,
+			   int feat __unused, int fd, void *data __used)
+{
+	ph->info.version = do_read_string(fd, ph);
+	return ph->info.version ? 0 : -ENOMEM;
+}
+
+static int process_arch(struct perf_file_section *section __unused,
+			struct perf_header *ph,
+			int feat __unused, int fd, void *data __used)
+{
+	ph->info.arch = do_read_string(fd, ph);
+	return ph->info.arch ? 0 : -ENOMEM;
+}
+
+static int process_nrcpus(struct perf_file_section *section __unused,
+			  struct perf_header *ph,
+			  int feat __unused, int fd, void *data __used)
+{
+	size_t ret;
+	u32 nr;
+
+	ret = read(fd, &nr, sizeof(nr));
+	if (ret != sizeof(nr))
+		return -1;
+
+	if (ph->needs_swap)
+		nr = bswap_32(nr);
+
+	ph->info.nr_cpus_online = nr;
+
+	ret = read(fd, &nr, sizeof(nr));
+	if (ret != sizeof(nr))
+		return -1;
+
+	if (ph->needs_swap)
+		nr = bswap_32(nr);
+
+	ph->info.nr_cpus_avail = nr;
+	return 0;
+}
+
+static int process_cpudesc(struct perf_file_section *section __unused,
+			   struct perf_header *ph,
+			   int feat __unused, int fd, void *data __used)
+{
+	ph->info.cpu_desc = do_read_string(fd, ph);
+	return ph->info.cpu_desc ? 0 : -ENOMEM;
+}
+
+static int process_cpuid(struct perf_file_section *section __unused,
+			 struct perf_header *ph,
+			 int feat __unused, int fd, void *data __used)
+{
+	ph->info.cpuid = do_read_string(fd, ph);
+	return ph->info.cpuid ? 0 : -ENOMEM;
+}
+
+static int process_total_mem(struct perf_file_section *section __unused,
+			     struct perf_header *ph,
+			     int feat __unused, int fd, void *data __used)
+{
+	uint64_t mem;
+	size_t ret;
+
+	ret = read(fd, &mem, sizeof(mem));
+	if (ret != sizeof(mem))
+		return -1;
+
+	if (ph->needs_swap)
+		mem = bswap_64(mem);
+
+	ph->info.total_mem = mem;
+	return 0;
+}
+
 static struct perf_evsel *
 perf_evlist__find_by_index(struct perf_evlist *evlist, int idx)
 {
@@ -1723,6 +1817,208 @@ process_event_desc(struct perf_file_section *section __maybe_unused,
 	return 0;
 }
 
+static int process_cmdline(struct perf_file_section *section __unused,
+			   struct perf_header *ph,
+			   int feat __unused, int fd, void *data __used)
+{
+	size_t ret;
+	char *str;
+	u32 nr, i;
+	struct strbuf sb;
+
+	ret = read(fd, &nr, sizeof(nr));
+	if (ret != sizeof(nr))
+		return -1;
+
+	if (ph->needs_swap)
+		nr = bswap_32(nr);
+
+	ph->info.nr_cmdline = nr;
+	strbuf_init(&sb, 128);
+
+	for (i = 0; i < nr; i++) {
+		str = do_read_string(fd, ph);
+		if (!str)
+			goto error;
+
+		/* include a NULL character at the end */
+		strbuf_add(&sb, str, strlen(str) + 1);
+		free(str);
+	}
+	ph->info.cmdline = strbuf_detach(&sb, NULL);
+	return 0;
+
+error:
+	strbuf_release(&sb);
+	return -1;
+}
+
+static int process_cpu_topology(struct perf_file_section *section __unused,
+				struct perf_header *ph,
+				int feat __unused, int fd, void *data __used)
+{
+	size_t ret;
+	u32 nr, i;
+	char *str;
+	struct strbuf sb;
+
+	ret = read(fd, &nr, sizeof(nr));
+	if (ret != sizeof(nr))
+		return -1;
+
+	if (ph->needs_swap)
+		nr = bswap_32(nr);
+
+	ph->info.nr_sibling_cores = nr;
+	strbuf_init(&sb, 128);
+
+	for (i = 0; i < nr; i++) {
+		str = do_read_string(fd, ph);
+		if (!str)
+			goto error;
+
+		/* include a NULL character at the end */
+		strbuf_add(&sb, str, strlen(str) + 1);
+		free(str);
+	}
+	ph->info.sibling_cores = strbuf_detach(&sb, NULL);
+
+	ret = read(fd, &nr, sizeof(nr));
+	if (ret != sizeof(nr))
+		return -1;
+
+	if (ph->needs_swap)
+		nr = bswap_32(nr);
+
+	ph->info.nr_sibling_threads = nr;
+
+	for (i = 0; i < nr; i++) {
+		str = do_read_string(fd, ph);
+		if (!str)
+			goto error;
+
+		/* include a NULL character at the end */
+		strbuf_add(&sb, str, strlen(str) + 1);
+		free(str);
+	}
+	ph->info.sibling_threads = strbuf_detach(&sb, NULL);
+	return 0;
+
+error:
+	strbuf_release(&sb);
+	return -1;
+}
+
+static int process_numa_topology(struct perf_file_section *section __unused,
+				 struct perf_header *ph,
+				 int feat __unused, int fd, void *data __used)
+{
+	size_t ret;
+	u32 nr, node, i;
+	char *str;
+	uint64_t mem_total, mem_free;
+	struct strbuf sb;
+
+	/* nr nodes */
+	ret = read(fd, &nr, sizeof(nr));
+	if (ret != sizeof(nr))
+		goto error;
+
+	if (ph->needs_swap)
+		nr = bswap_32(nr);
+
+	ph->info.nr_numa_nodes = nr;
+	strbuf_init(&sb, 256);
+
+	for (i = 0; i < nr; i++) {
+		/* node number */
+		ret = read(fd, &node, sizeof(node));
+		if (ret != sizeof(node))
+			goto error;
+
+		ret = read(fd, &mem_total, sizeof(u64));
+		if (ret != sizeof(u64))
+			goto error;
+
+		ret = read(fd, &mem_free, sizeof(u64));
+		if (ret != sizeof(u64))
+			goto error;
+
+		if (ph->needs_swap) {
+			node = bswap_32(node);
+			mem_total = bswap_64(mem_total);
+			mem_free = bswap_64(mem_free);
+		}
+
+		strbuf_addf(&sb, "%u:%"PRIu64":%"PRIu64":",
+			    node, mem_total, mem_free);
+
+		str = do_read_string(fd, ph);
+		if (!str)
+			goto error;
+
+		/* include a NULL character at the end */
+		strbuf_add(&sb, str, strlen(str) + 1);
+		free(str);
+	}
+	ph->info.numa_nodes = strbuf_detach(&sb, NULL);
+	return 0;
+
+error:
+	strbuf_release(&sb);
+	return -1;
+}
+
+static int process_pmu_mappings(struct perf_file_section *section __unused,
+				struct perf_header *ph,
+				int feat __unused, int fd, void *data __used)
+{
+	size_t ret;
+	char *name;
+	u32 pmu_num;
+	u32 type;
+	struct strbuf sb;
+
+	ret = read(fd, &pmu_num, sizeof(pmu_num));
+	if (ret != sizeof(pmu_num))
+		return -1;
+
+	if (ph->needs_swap)
+		pmu_num = bswap_32(pmu_num);
+
+	if (!pmu_num) {
+		pr_debug("pmu mappings not available\n");
+		return 0;
+	}
+
+	ph->info.nr_pmu_mappings = pmu_num;
+	strbuf_init(&sb, 128);
+
+	while (pmu_num) {
+		if (read(fd, &type, sizeof(type)) != sizeof(type))
+			goto error;
+		if (ph->needs_swap)
+			type = bswap_32(type);
+
+		name = do_read_string(fd, ph);
+		if (!name)
+			goto error;
+
+		strbuf_addf(&sb, "%u:%s", type, name);
+		/* include a NULL character at the end */
+		strbuf_add(&sb, "", 1);
+
+		free(name);
+		pmu_num--;
+	}
+	ph->info.pmu_mappings = strbuf_detach(&sb, NULL);
+	return 0;
+
+error:
+	strbuf_release(&sb);
+	return -1;
+}
+
 struct feature_ops {
 	int (*write)(int fd, struct perf_header *h, struct perf_evlist *evlist);
 	void (*print)(struct perf_header *h, int fd, FILE *fp);
@@ -1739,7 +2035,7 @@ struct feature_ops {
 		.process = process_##func }
 #define FEAT_OPF(n, func) \
 	[n] = { .name = #n, .write = write_##func, .print = print_##func, \
-		.full_only = true }
+		.process = process_##func, .full_only = true }
 
 /* feature_ops not implemented: */
 #define print_tracing_data	NULL
@@ -1748,20 +2044,20 @@ struct feature_ops {
 static const struct feature_ops feat_ops[HEADER_LAST_FEATURE] = {
 	FEAT_OPP(HEADER_TRACING_DATA,	tracing_data),
 	FEAT_OPP(HEADER_BUILD_ID,	build_id),
-	FEAT_OPA(HEADER_HOSTNAME,	hostname),
-	FEAT_OPA(HEADER_OSRELEASE,	osrelease),
-	FEAT_OPA(HEADER_VERSION,	version),
-	FEAT_OPA(HEADER_ARCH,		arch),
-	FEAT_OPA(HEADER_NRCPUS,		nrcpus),
-	FEAT_OPA(HEADER_CPUDESC,	cpudesc),
-	FEAT_OPA(HEADER_CPUID,		cpuid),
-	FEAT_OPA(HEADER_TOTAL_MEM,	total_mem),
+	FEAT_OPP(HEADER_HOSTNAME,	hostname),
+	FEAT_OPP(HEADER_OSRELEASE,	osrelease),
+	FEAT_OPP(HEADER_VERSION,	version),
+	FEAT_OPP(HEADER_ARCH,		arch),
+	FEAT_OPP(HEADER_NRCPUS,		nrcpus),
+	FEAT_OPP(HEADER_CPUDESC,	cpudesc),
+	FEAT_OPP(HEADER_CPUID,		cpuid),
+	FEAT_OPP(HEADER_TOTAL_MEM,	total_mem),
 	FEAT_OPP(HEADER_EVENT_DESC,	event_desc),
-	FEAT_OPA(HEADER_CMDLINE,	cmdline),
+	FEAT_OPP(HEADER_CMDLINE,	cmdline),
 	FEAT_OPF(HEADER_CPU_TOPOLOGY,	cpu_topology),
 	FEAT_OPF(HEADER_NUMA_TOPOLOGY,	numa_topology),
 	FEAT_OPA(HEADER_BRANCH_STACK,	branch_stack),
-	FEAT_OPA(HEADER_PMU_MAPPINGS,	pmu_mappings),
+	FEAT_OPP(HEADER_PMU_MAPPINGS,	pmu_mappings),
 };
 
 struct header_print_data {
-- 
1.7.11.4

[PATCH 3/4] perf header: Use pre-processed header info when printing

[Namhyung Kim]

>From now on each feature information is processed and saved in perf
header so that it can be used for printing.  The event desc and branch
stack features are not touched since they're not saved.

Cc: Stephane Eranian <eranian@google.com>
Cc: Robert Richter <robert.richter@amd.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/util/header.c | 279 +++++++++++++++++------------------------------
 1 file changed, 102 insertions(+), 177 deletions(-)

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index fd29d42dedbe..ab5ebe8afbc6 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -1103,118 +1103,80 @@ static int write_branch_stack(int fd __maybe_unused,
 	return 0;
 }
 
-static void print_hostname(struct perf_header *ph, int fd, FILE *fp)
+static void print_hostname(struct perf_header *ph, int fd __maybe_unused,
+			   FILE *fp)
 {
-	char *str = do_read_string(fd, ph);
-	fprintf(fp, "# hostname : %s\n", str);
-	free(str);
+	fprintf(fp, "# hostname : %s\n", ph->info.hostname);
 }
 
-static void print_osrelease(struct perf_header *ph, int fd, FILE *fp)
+static void print_osrelease(struct perf_header *ph, int fd __maybe_unused,
+			    FILE *fp)
 {
-	char *str = do_read_string(fd, ph);
-	fprintf(fp, "# os release : %s\n", str);
-	free(str);
+	fprintf(fp, "# os release : %s\n", ph->info.os_release);
 }
 
-static void print_arch(struct perf_header *ph, int fd, FILE *fp)
+static void print_arch(struct perf_header *ph, int fd __maybe_unused, FILE *fp)
 {
-	char *str = do_read_string(fd, ph);
-	fprintf(fp, "# arch : %s\n", str);
-	free(str);
+	fprintf(fp, "# arch : %s\n", ph->info.arch);
 }
 
-static void print_cpudesc(struct perf_header *ph, int fd, FILE *fp)
+static void print_cpudesc(struct perf_header *ph, int fd __maybe_unused,
+			  FILE *fp)
 {
-	char *str = do_read_string(fd, ph);
-	fprintf(fp, "# cpudesc : %s\n", str);
-	free(str);
+	fprintf(fp, "# cpudesc : %s\n", ph->info.cpu_desc);
 }
 
-static void print_nrcpus(struct perf_header *ph, int fd, FILE *fp)
+static void print_nrcpus(struct perf_header *ph, int fd __maybe_unused,
+			 FILE *fp)
 {
-	ssize_t ret;
-	u32 nr;
-
-	ret = read(fd, &nr, sizeof(nr));
-	if (ret != (ssize_t)sizeof(nr))
-		nr = -1; /* interpreted as error */
-
-	if (ph->needs_swap)
-		nr = bswap_32(nr);
-
-	fprintf(fp, "# nrcpus online : %u\n", nr);
-
-	ret = read(fd, &nr, sizeof(nr));
-	if (ret != (ssize_t)sizeof(nr))
-		nr = -1; /* interpreted as error */
-
-	if (ph->needs_swap)
-		nr = bswap_32(nr);
-
-	fprintf(fp, "# nrcpus avail : %u\n", nr);
+	fprintf(fp, "# nrcpus online : %u\n", ph->info.nr_cpus_online);
+	fprintf(fp, "# nrcpus avail : %u\n", ph->info.nr_cpus_avail);
 }
 
-static void print_version(struct perf_header *ph, int fd, FILE *fp)
+static void print_version(struct perf_header *ph, int fd __maybe_unused,
+			  FILE *fp)
 {
-	char *str = do_read_string(fd, ph);
-	fprintf(fp, "# perf version : %s\n", str);
-	free(str);
+	fprintf(fp, "# perf version : %s\n", ph->info.version);
 }
 
-static void print_cmdline(struct perf_header *ph, int fd, FILE *fp)
+static void print_cmdline(struct perf_header *ph, int fd __maybe_unused,
+			  FILE *fp)
 {
-	ssize_t ret;
+	int nr, i;
 	char *str;
-	u32 nr, i;
-
-	ret = read(fd, &nr, sizeof(nr));
-	if (ret != (ssize_t)sizeof(nr))
-		return;
 
-	if (ph->needs_swap)
-		nr = bswap_32(nr);
+	nr = ph->info.nr_cmdline;
+	str = ph->info.cmdline;
 
 	fprintf(fp, "# cmdline : ");
 
 	for (i = 0; i < nr; i++) {
-		str = do_read_string(fd, ph);
 		fprintf(fp, "%s ", str);
-		free(str);
+		str += strlen(str) + 1;
 	}
 	fputc('\n', fp);
 }
 
-static void print_cpu_topology(struct perf_header *ph, int fd, FILE *fp)
+static void print_cpu_topology(struct perf_header *ph, int fd __maybe_unused,
+			       FILE *fp)
 {
-	ssize_t ret;
-	u32 nr, i;
+	int nr, i;
 	char *str;
 
-	ret = read(fd, &nr, sizeof(nr));
-	if (ret != (ssize_t)sizeof(nr))
-		return;
-
-	if (ph->needs_swap)
-		nr = bswap_32(nr);
+	nr = ph->info.nr_sibling_cores;
+	str = ph->info.sibling_cores;
 
 	for (i = 0; i < nr; i++) {
-		str = do_read_string(fd, ph);
 		fprintf(fp, "# sibling cores   : %s\n", str);
-		free(str);
+		str += strlen(str) + 1;
 	}
 
-	ret = read(fd, &nr, sizeof(nr));
-	if (ret != (ssize_t)sizeof(nr))
-		return;
-
-	if (ph->needs_swap)
-		nr = bswap_32(nr);
+	nr = ph->info.nr_sibling_threads;
+	str = ph->info.sibling_threads;
 
 	for (i = 0; i < nr; i++) {
-		str = do_read_string(fd, ph);
 		fprintf(fp, "# sibling threads : %s\n", str);
-		free(str);
+		str += strlen(str) + 1;
 	}
 }
 
@@ -1375,126 +1337,89 @@ static void print_event_desc(struct perf_header *ph, int fd, FILE *fp)
 	free_event_desc(events);
 }
 
-static void print_total_mem(struct perf_header *h __maybe_unused, int fd,
+static void print_total_mem(struct perf_header *ph, int fd __maybe_unused,
 			    FILE *fp)
 {
-	uint64_t mem;
-	ssize_t ret;
-
-	ret = read(fd, &mem, sizeof(mem));
-	if (ret != sizeof(mem))
-		goto error;
-
-	if (h->needs_swap)
-		mem = bswap_64(mem);
-
-	fprintf(fp, "# total memory : %"PRIu64" kB\n", mem);
-	return;
-error:
-	fprintf(fp, "# total memory : unknown\n");
+	fprintf(fp, "# total memory : %Lu kB\n", ph->info.total_mem);
 }
 
-static void print_numa_topology(struct perf_header *h __maybe_unused, int fd,
+static void print_numa_topology(struct perf_header *ph, int fd __maybe_unused,
 				FILE *fp)
 {
-	ssize_t ret;
 	u32 nr, c, i;
-	char *str;
+	char *str, *tmp;
 	uint64_t mem_total, mem_free;
 
 	/* nr nodes */
-	ret = read(fd, &nr, sizeof(nr));
-	if (ret != (ssize_t)sizeof(nr))
-		goto error;
-
-	if (h->needs_swap)
-		nr = bswap_32(nr);
+	nr = ph->info.nr_numa_nodes;
+	str = ph->info.numa_nodes;
 
 	for (i = 0; i < nr; i++) {
-
 		/* node number */
-		ret = read(fd, &c, sizeof(c));
-		if (ret != (ssize_t)sizeof(c))
+		c = strtoul(str, &tmp, 0);
+		if (*tmp != ':')
 			goto error;
 
-		if (h->needs_swap)
-			c = bswap_32(c);
-
-		ret = read(fd, &mem_total, sizeof(u64));
-		if (ret != sizeof(u64))
+		str = tmp + 1;
+		mem_total = strtoull(str, &tmp, 0);
+		if (*tmp != ':')
 			goto error;
 
-		ret = read(fd, &mem_free, sizeof(u64));
-		if (ret != sizeof(u64))
+		str = tmp + 1;
+		mem_free = strtoull(str, &tmp, 0);
+		if (*tmp != ':')
 			goto error;
 
-		if (h->needs_swap) {
-			mem_total = bswap_64(mem_total);
-			mem_free = bswap_64(mem_free);
-		}
-
 		fprintf(fp, "# node%u meminfo  : total = %"PRIu64" kB,"
 			    " free = %"PRIu64" kB\n",
-			c,
-			mem_total,
-			mem_free);
+			c, mem_total, mem_free);
 
-		str = do_read_string(fd, h);
+		str = tmp + 1;
 		fprintf(fp, "# node%u cpu list : %s\n", c, str);
-		free(str);
 	}
 	return;
 error:
 	fprintf(fp, "# numa topology : not available\n");
 }
 
-static void print_cpuid(struct perf_header *ph, int fd, FILE *fp)
+static void print_cpuid(struct perf_header *ph, int fd __maybe_unused, FILE *fp)
 {
-	char *str = do_read_string(fd, ph);
-	fprintf(fp, "# cpuid : %s\n", str);
-	free(str);
+	fprintf(fp, "# cpuid : %s\n", ph->info.cpuid);
 }
 
 static void print_branch_stack(struct perf_header *ph __maybe_unused,
-			       int fd __maybe_unused,
-			       FILE *fp)
+			       int fd __maybe_unused, FILE *fp)
 {
 	fprintf(fp, "# contains samples with branch stack\n");
 }
 
-static void print_pmu_mappings(struct perf_header *ph, int fd, FILE *fp)
+static void print_pmu_mappings(struct perf_header *ph, int fd __maybe_unused,
+			       FILE *fp)
 {
 	const char *delimiter = "# pmu mappings: ";
-	char *name;
-	int ret;
+	char *str, *tmp;
 	u32 pmu_num;
 	u32 type;
 
-	ret = read(fd, &pmu_num, sizeof(pmu_num));
-	if (ret != sizeof(pmu_num))
-		goto error;
-
-	if (ph->needs_swap)
-		pmu_num = bswap_32(pmu_num);
-
+	pmu_num = ph->info.nr_pmu_mappings;
 	if (!pmu_num) {
 		fprintf(fp, "# pmu mappings: not available\n");
 		return;
 	}
 
+	str = ph->info.pmu_mappings;
+
 	while (pmu_num) {
-		if (read(fd, &type, sizeof(type)) != sizeof(type))
-			break;
-		if (ph->needs_swap)
-			type = bswap_32(type);
+		type = strtoul(str, &tmp, 0);
+		if (*tmp != ':')
+			goto error;
+
+		str = tmp + 1;
+		fprintf(fp, "%s%s = %" PRIu32, delimiter, str, type);
 
-		name = do_read_string(fd, ph);
-		if (!name)
-			break;
-		pmu_num--;
-		fprintf(fp, "%s%s = %" PRIu32, delimiter, name, type);
-		free(name);
 		delimiter = ", ";
+		str += strlen(str) + 1;
+		pmu_num--;
 	}
 
 	fprintf(fp, "\n");
@@ -1674,41 +1599,41 @@ static int process_build_id(struct perf_file_section *section,
 	return 0;
 }
 
-static int process_hostname(struct perf_file_section *section __unused,
-			    struct perf_header *ph,
-			    int feat __unused, int fd, void *data __used)
+static int process_hostname(struct perf_file_section *section __maybe_unused,
+			    struct perf_header *ph, int feat __maybe_unused,
+			    int fd, void *data __maybe_unused)
 {
 	ph->info.hostname = do_read_string(fd, ph);
 	return ph->info.hostname ? 0 : -ENOMEM;
 }
 
-static int process_osrelease(struct perf_file_section *section __unused,
-			     struct perf_header *ph,
-			     int feat __unused, int fd, void *data __used)
+static int process_osrelease(struct perf_file_section *section __maybe_unused,
+			     struct perf_header *ph, int feat __maybe_unused,
+			     int fd, void *data __maybe_unused)
 {
 	ph->info.os_release = do_read_string(fd, ph);
 	return ph->info.os_release ? 0 : -ENOMEM;
 }
 
-static int process_version(struct perf_file_section *section __unused,
-			   struct perf_header *ph,
-			   int feat __unused, int fd, void *data __used)
+static int process_version(struct perf_file_section *section __maybe_unused,
+			   struct perf_header *ph, int feat __maybe_unused,
+			   int fd, void *data __maybe_unused)
 {
 	ph->info.version = do_read_string(fd, ph);
 	return ph->info.version ? 0 : -ENOMEM;
 }
 
-static int process_arch(struct perf_file_section *section __unused,
-			struct perf_header *ph,
-			int feat __unused, int fd, void *data __used)
+static int process_arch(struct perf_file_section *section __maybe_unused,
+			struct perf_header *ph, int feat __maybe_unused,
+			int fd, void *data __maybe_unused)
 {
 	ph->info.arch = do_read_string(fd, ph);
 	return ph->info.arch ? 0 : -ENOMEM;
 }
 
-static int process_nrcpus(struct perf_file_section *section __unused,
-			  struct perf_header *ph,
-			  int feat __unused, int fd, void *data __used)
+static int process_nrcpus(struct perf_file_section *section __maybe_unused,
+			  struct perf_header *ph, int feat __maybe_unused,
+			  int fd, void *data __maybe_unused)
 {
 	size_t ret;
 	u32 nr;
@@ -1733,25 +1658,25 @@ static int process_nrcpus(struct perf_file_section *section __unused,
 	return 0;
 }
 
-static int process_cpudesc(struct perf_file_section *section __unused,
-			   struct perf_header *ph,
-			   int feat __unused, int fd, void *data __used)
+static int process_cpudesc(struct perf_file_section *section __maybe_unused,
+			   struct perf_header *ph, int feat __maybe_unused,
+			   int fd, void *data __maybe_unused)
 {
 	ph->info.cpu_desc = do_read_string(fd, ph);
 	return ph->info.cpu_desc ? 0 : -ENOMEM;
 }
 
-static int process_cpuid(struct perf_file_section *section __unused,
-			 struct perf_header *ph,
-			 int feat __unused, int fd, void *data __used)
+static int process_cpuid(struct perf_file_section *section __maybe_unused,
+			 struct perf_header *ph, int feat __maybe_unused,
+			 int fd, void *data __maybe_unused)
 {
 	ph->info.cpuid = do_read_string(fd, ph);
 	return ph->info.cpuid ? 0 : -ENOMEM;
 }
 
-static int process_total_mem(struct perf_file_section *section __unused,
-			     struct perf_header *ph,
-			     int feat __unused, int fd, void *data __used)
+static int process_total_mem(struct perf_file_section *section __maybe_unused,
+			     struct perf_header *ph, int feat __maybe_unused,
+			     int fd, void *data __maybe_unused)
 {
 	uint64_t mem;
 	size_t ret;
@@ -1817,9 +1742,9 @@ process_event_desc(struct perf_file_section *section __maybe_unused,
 	return 0;
 }
 
-static int process_cmdline(struct perf_file_section *section __unused,
-			   struct perf_header *ph,
-			   int feat __unused, int fd, void *data __used)
+static int process_cmdline(struct perf_file_section *section __maybe_unused,
+			   struct perf_header *ph, int feat __maybe_unused,
+			   int fd, void *data __maybe_unused)
 {
 	size_t ret;
 	char *str;
@@ -1853,9 +1778,9 @@ error:
 	return -1;
 }
 
-static int process_cpu_topology(struct perf_file_section *section __unused,
-				struct perf_header *ph,
-				int feat __unused, int fd, void *data __used)
+static int process_cpu_topology(struct perf_file_section *section __maybe_unused,
+				struct perf_header *ph, int feat __maybe_unused,
+				int fd, void *data __maybe_unused)
 {
 	size_t ret;
 	u32 nr, i;
@@ -1909,9 +1834,9 @@ error:
 	return -1;
 }
 
-static int process_numa_topology(struct perf_file_section *section __unused,
-				 struct perf_header *ph,
-				 int feat __unused, int fd, void *data __used)
+static int process_numa_topology(struct perf_file_section *section __maybe_unused,
+				 struct perf_header *ph, int feat __maybe_unused,
+				 int fd, void *data __maybe_unused)
 {
 	size_t ret;
 	u32 nr, node, i;
@@ -1969,9 +1894,9 @@ error:
 	return -1;
 }
 
-static int process_pmu_mappings(struct perf_file_section *section __unused,
-				struct perf_header *ph,
-				int feat __unused, int fd, void *data __used)
+static int process_pmu_mappings(struct perf_file_section *section __maybe_unused,
+				struct perf_header *ph, int feat __maybe_unused,
+				int fd, void *data __maybe_unused)
 {
 	size_t ret;
 	char *name;
-- 
1.7.11.4

[PATCH 4/4] perf header: Remove unused @feat arg from ->process callback

[Namhyung Kim]

From: Namhyung Kim <namhyung.kim@lge.com>

As the @feat arg is not used anywhere, get rid of it from the signature.

Cc: Stephane Eranian <eranian@google.com>
Cc: Robert Richter <robert.richter@amd.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/util/header.c | 70 ++++++++++++++++++++++++------------------------
 1 file changed, 35 insertions(+), 35 deletions(-)

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index ab5ebe8afbc6..ee58d75de65f 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -1580,18 +1580,16 @@ out:
 	return err;
 }
 
-static int process_tracing_data(struct perf_file_section *section
-				__maybe_unused,
-			      struct perf_header *ph __maybe_unused,
-			      int feat __maybe_unused, int fd, void *data)
+static int process_tracing_data(struct perf_file_section *section __maybe_unused,
+				struct perf_header *ph __maybe_unused,
+				int fd, void *data)
 {
 	trace_report(fd, data, false);
 	return 0;
 }
 
 static int process_build_id(struct perf_file_section *section,
-			    struct perf_header *ph,
-			    int feat __maybe_unused, int fd,
+			    struct perf_header *ph, int fd,
 			    void *data __maybe_unused)
 {
 	if (perf_header__read_build_ids(ph, fd, section->offset, section->size))
@@ -1600,40 +1598,40 @@ static int process_build_id(struct perf_file_section *section,
 }
 
 static int process_hostname(struct perf_file_section *section __maybe_unused,
-			    struct perf_header *ph, int feat __maybe_unused,
-			    int fd, void *data __maybe_unused)
+			    struct perf_header *ph, int fd,
+			    void *data __maybe_unused)
 {
 	ph->info.hostname = do_read_string(fd, ph);
 	return ph->info.hostname ? 0 : -ENOMEM;
 }
 
 static int process_osrelease(struct perf_file_section *section __maybe_unused,
-			     struct perf_header *ph, int feat __maybe_unused,
-			     int fd, void *data __maybe_unused)
+			     struct perf_header *ph, int fd,
+			     void *data __maybe_unused)
 {
 	ph->info.os_release = do_read_string(fd, ph);
 	return ph->info.os_release ? 0 : -ENOMEM;
 }
 
 static int process_version(struct perf_file_section *section __maybe_unused,
-			   struct perf_header *ph, int feat __maybe_unused,
-			   int fd, void *data __maybe_unused)
+			   struct perf_header *ph, int fd,
+			   void *data __maybe_unused)
 {
 	ph->info.version = do_read_string(fd, ph);
 	return ph->info.version ? 0 : -ENOMEM;
 }
 
 static int process_arch(struct perf_file_section *section __maybe_unused,
-			struct perf_header *ph, int feat __maybe_unused,
-			int fd, void *data __maybe_unused)
+			struct perf_header *ph,	int fd,
+			void *data __maybe_unused)
 {
 	ph->info.arch = do_read_string(fd, ph);
 	return ph->info.arch ? 0 : -ENOMEM;
 }
 
 static int process_nrcpus(struct perf_file_section *section __maybe_unused,
-			  struct perf_header *ph, int feat __maybe_unused,
-			  int fd, void *data __maybe_unused)
+			  struct perf_header *ph, int fd,
+			  void *data __maybe_unused)
 {
 	size_t ret;
 	u32 nr;
@@ -1659,24 +1657,24 @@ static int process_nrcpus(struct perf_file_section *section __maybe_unused,
 }
 
 static int process_cpudesc(struct perf_file_section *section __maybe_unused,
-			   struct perf_header *ph, int feat __maybe_unused,
-			   int fd, void *data __maybe_unused)
+			   struct perf_header *ph, int fd,
+			   void *data __maybe_unused)
 {
 	ph->info.cpu_desc = do_read_string(fd, ph);
 	return ph->info.cpu_desc ? 0 : -ENOMEM;
 }
 
 static int process_cpuid(struct perf_file_section *section __maybe_unused,
-			 struct perf_header *ph, int feat __maybe_unused,
-			 int fd, void *data __maybe_unused)
+			 struct perf_header *ph,  int fd,
+			 void *data __maybe_unused)
 {
 	ph->info.cpuid = do_read_string(fd, ph);
 	return ph->info.cpuid ? 0 : -ENOMEM;
 }
 
 static int process_total_mem(struct perf_file_section *section __maybe_unused,
-			     struct perf_header *ph, int feat __maybe_unused,
-			     int fd, void *data __maybe_unused)
+			     struct perf_header *ph, int fd,
+			     void *data __maybe_unused)
 {
 	uint64_t mem;
 	size_t ret;
@@ -1706,7 +1704,8 @@ perf_evlist__find_by_index(struct perf_evlist *evlist, int idx)
 }
 
 static void
-perf_evlist__set_event_name(struct perf_evlist *evlist, struct perf_evsel *event)
+perf_evlist__set_event_name(struct perf_evlist *evlist,
+			    struct perf_evsel *event)
 {
 	struct perf_evsel *evsel;
 
@@ -1725,15 +1724,16 @@ perf_evlist__set_event_name(struct perf_evlist *evlist, struct perf_evsel *event
 
 static int
 process_event_desc(struct perf_file_section *section __maybe_unused,
-		   struct perf_header *header, int feat __maybe_unused, int fd,
+		   struct perf_header *header, int fd,
 		   void *data __maybe_unused)
 {
-	struct perf_session *session = container_of(header, struct perf_session, header);
+	struct perf_session *session;
 	struct perf_evsel *evsel, *events = read_event_desc(header, fd);
 
 	if (!events)
 		return 0;
 
+	session = container_of(header, struct perf_session, header);
 	for (evsel = events; evsel->attr.size; evsel++)
 		perf_evlist__set_event_name(session->evlist, evsel);
 
@@ -1743,8 +1743,8 @@ process_event_desc(struct perf_file_section *section __maybe_unused,
 }
 
 static int process_cmdline(struct perf_file_section *section __maybe_unused,
-			   struct perf_header *ph, int feat __maybe_unused,
-			   int fd, void *data __maybe_unused)
+			   struct perf_header *ph, int fd,
+			   void *data __maybe_unused)
 {
 	size_t ret;
 	char *str;
@@ -1779,8 +1779,8 @@ error:
 }
 
 static int process_cpu_topology(struct perf_file_section *section __maybe_unused,
-				struct perf_header *ph, int feat __maybe_unused,
-				int fd, void *data __maybe_unused)
+				struct perf_header *ph, int fd,
+				void *data __maybe_unused)
 {
 	size_t ret;
 	u32 nr, i;
@@ -1835,8 +1835,8 @@ error:
 }
 
 static int process_numa_topology(struct perf_file_section *section __maybe_unused,
-				 struct perf_header *ph, int feat __maybe_unused,
-				 int fd, void *data __maybe_unused)
+				 struct perf_header *ph, int fd,
+				 void *data __maybe_unused)
 {
 	size_t ret;
 	u32 nr, node, i;
@@ -1895,8 +1895,8 @@ error:
 }
 
 static int process_pmu_mappings(struct perf_file_section *section __maybe_unused,
-				struct perf_header *ph, int feat __maybe_unused,
-				int fd, void *data __maybe_unused)
+				struct perf_header *ph, int fd,
+				void *data __maybe_unused)
 {
 	size_t ret;
 	char *name;
@@ -1948,7 +1948,7 @@ struct feature_ops {
 	int (*write)(int fd, struct perf_header *h, struct perf_evlist *evlist);
 	void (*print)(struct perf_header *h, int fd, FILE *fp);
 	int (*process)(struct perf_file_section *section,
-		       struct perf_header *h, int feat, int fd, void *data);
+		       struct perf_header *h, int fd, void *data);
 	const char *name;
 	bool full_only;
 };
@@ -2462,7 +2462,7 @@ static int perf_file_section__process(struct perf_file_section *section,
 	if (!feat_ops[feat].process)
 		return 0;
 
-	return feat_ops[feat].process(section, ph, feat, fd, data);
+	return feat_ops[feat].process(section, ph, fd, data);
 }
 
 static int perf_file_header__read_pipe(struct perf_pipe_file_header *header,
-- 
1.7.11.4

Re: [PATCH 1/4] perf header: Add struct perf_header_info

[Arnaldo Carvalho de Melo]

Em Thu, Sep 20, 2012 at 02:36:44PM +0900, Namhyung Kim escreveu:
> From: Namhyung Kim <namhyung.kim@lge.com>
> 
> The struct perf_header_info will preserve environment information at
> the time of perf record.  It can be accessed anytime after parsing a
> perf.data file if needed.
 
> +struct perf_header_info {

I think it would be better named as 'perf_session_env' i.e. the
environment (machine (name), hardware(nr_cpus, total_mem, etc) and
OS(release, version) details) where a 'perf' 'session' took place.

perf 'header info' look more like 'what is the version in the header?
what about its endianity, and other 'header' details :-)

> +	char			*hostname;
> +	char			*os_release;
> +	char			*version;
> +	char			*arch;
> +	int			nr_cpus_online;
> +	int			nr_cpus_avail;
> +	char			*cpu_desc;
> +	char			*cpuid;
> +	unsigned long long	total_mem;
> +
> +	int			nr_cmdline;
> +	char			*cmdline;
> +	int			nr_sibling_cores;
> +	char			*sibling_cores;
> +	int			nr_sibling_threads;
> +	char			*sibling_threads;
> +	int			nr_numa_nodes;
> +	char			*numa_nodes;
> +	int			nr_pmu_mappings;
> +	char			*pmu_mappings;
> +};
> +
>  struct perf_header {
>  	int			frozen;
>  	bool			needs_swap;
> @@ -67,6 +90,7 @@ struct perf_header {
>  	u64			event_offset;
>  	u64			event_size;
>  	DECLARE_BITMAP(adds_features, HEADER_FEAT_BITS);
> +	struct perf_header_info info;
>  };
>  
>  struct perf_evlist;
> -- 
> 1.7.11.4

Re: [PATCH 0/4] perf header: Save and reuse feature information in header (v3)

[David Ahern]

On 9/19/12 11:36 PM, Namhyung Kim wrote:
> Hi,
>
> Currently the perf header information is used only at initial setup
> time and discarded.  If it's saved we could reuse the information for
> various purpose in the future.

When this gets settled can you update builtin-kvm too? The kvm-events 
patch too adds a perf_file_section__read_feature() function for 
extracting cpuid from the header.

David

Re: [PATCH 1/4] perf header: Add struct perf_header_info

[Namhyung Kim]

2012-09-20 (목), 04:43 -0700, Arnaldo Carvalho de Melo:
> Em Thu, Sep 20, 2012 at 02:36:44PM +0900, Namhyung Kim escreveu:
> > From: Namhyung Kim <namhyung.kim@lge.com>
> > 
> > The struct perf_header_info will preserve environment information at
> > the time of perf record.  It can be accessed anytime after parsing a
> > perf.data file if needed.
>  
> > +struct perf_header_info {
> 
> I think it would be better named as 'perf_session_env' i.e. the
> environment (machine (name), hardware(nr_cpus, total_mem, etc) and
> OS(release, version) details) where a 'perf' 'session' took place.
> 
> perf 'header info' look more like 'what is the version in the header?
> what about its endianity, and other 'header' details :-)

Okay, will rename and resend tomorrow!

/me always failed to make a good name :(

Thanks,
Namhyung

Re: [PATCH 0/4] perf header: Save and reuse feature information in header (v3)

[Namhyung Kim]

Hi David,

2012-09-20 (목), 07:44 -0600, David Ahern:
> On 9/19/12 11:36 PM, Namhyung Kim wrote:
> > Currently the perf header information is used only at initial setup
> > time and discarded.  If it's saved we could reuse the information for
> > various purpose in the future.
> 
> When this gets settled can you update builtin-kvm too? The kvm-events 
> patch too adds a perf_file_section__read_feature() function for 
> extracting cpuid from the header.

Will look at it too.

Thanks,
Namhyung