Re: [PATCH] perf: make perf.data more self-descriptive (v4)
From: David Ahern
Date: Thu Sep 08 2011 - 11:28:11 EST
On 09/07/2011 01:10 PM, Stephane Eranian wrote:
>
> The goal of this patch is to include more information
> about the host environment into the perf.data so it is
> more self-descriptive. Overtime, profiles are captured
> on various machines and it becomes hard to track what
> was recorded, on what machine and when.
>
> This patch provides a way to solve this by extending
> the perf.data file with basic information about the
> host machine. To add those extensions, we leverage
> the feature bits capabilities of the perf.data format.
> The change is backward compatible with existing perf.data
> files.
>
> We define the following useful new extensions:
> - HEADER_HOSTNAME: the hostname
> - HEADER_OSRELEASE: the kernel release number
> - HEADER_ARCH: the hw architecture
> - HEADER_CPUID: the cpu model description
> - HEADER_NRCPUS: number of online/avail cpus
> - HEADER_CMDLINE: perf command line
> - HEADER_VERSION: perf version
> - HEADER_TOPOLOGY: cpu topology
> - HEADER_EVENT_DESC: full event description (attrs)
>
> The small granularity for the entries is to make it easier
> to extend without breaking backward compatiblity. All entries
> are provided as ASCII strings, easy to parse, except for the
> event description.
>
> In the second version, we dropped the -I option for the
> perf record command. The extra information is systematically
> captured. But it's still displayed optionally by perf report.
> There are also a couple of cleanups of function prototypes
> and global variables.
>
> In the third version, we:
> - fixed missing MIPS support for CPUID
> - used u32 instead of int when writing integers to file
> - fixed couple of bswap() bugs
> - refactorize all write/print functions using function pointers
> - improved write_cmdline() to include actual path to perf binary
>
> In the fourth version, we:
> - fixed a couple of int vs. u32 issues
> - factorized HEADER_BUILD_ID, HEADER_TRACE_INFO
> - added -I option to perf script report
> - reverted change to evsel.c (unrelated to meta-data)
> - modified write_*() to always write despite errors (adds_feature bit present)
> - added HEADER_TOTAL_MEM: total memory installed on this system
> - added HEADER_NUMA_TOPOLOGY: shows NUMA nodes and for each memory, cpu list
> - renamed HEADER_TOPOLOGY to HEADER_CPU_TOPOLOGY
Still some endianness problems; cross-endian analysis is causing perf to
abort. I need some time to investigate. I can send you a ppc data file
if you have the time.
David
>
>
> $ perf record -ecycles,instructions noploop 1
> noploop for 1 seconds
> [ perf record: Woken up 1 times to write data ]
> [ perf record: Captured and wrote 0.098 MB perf.data (~4260 samples) ]
> $ perf report -I --stdio
> #
> # captured on: Wed Sep 7 21:00:10 2011
> # hostname : quad
> # os release : 3.1.0-rc4-tip
> # arch : x86_64
> # cpuid : Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz
> # nrcpus online : 4
> # nrcpus avail : 4
> # event = cycles, type = 0, config = 0x0, config1 = 0x0, config2 = 0x0, excl_usr = 0, excl_kern = 0, id = { 536, 537, 538, 539 }
> # event = instructions, type = 0, config = 0x1, config1 = 0x0, config2 = 0x0, excl_usr = 0, excl_kern = 0, id = { 540, 541, 542,
> # cmdline : /home/eranian/perfmon/official/tip/build/tools/perf/perf record -ecycles,instructions noploop 1
> # perf version : 3.1.0-rc4
> # CPU0 sibling cores : 0-3
> # CPU0 sibling threads: 0
> # CPU1 sibling cores : 0-3
> # CPU1 sibling threads: 1
> # CPU2 sibling cores : 0-3
> # CPU2 sibling threads: 2
> # CPU3 sibling cores : 0-3
> # CPU3 sibling threads: 3
> # total memory: 8105344 kB
> # node0 meminfo : 8320608 kB
> # node0 cpu list: 0-3
> #
> # Events: 995 cycles
> #
> # Overhead Command Shared Object Symbol
> # ........ ....... ................. ....................
> #
> 99.90% noploop noploop [.] noploop
> 0.10% noploop [kernel.kallsyms] [k] trace_hardirqs_on
> 0.00% noploop [kernel.kallsyms] [k] lock_release
> 0.00% noploop [kernel.kallsyms] [k] intel_pmu_enable_all
> ...
>
>
> Signed-off-by: Stephane Eranian <eranian@xxxxxxxxxx>
> ---
>
> diff --git a/tools/perf/Documentation/perf-report.txt b/tools/perf/Documentation/perf-report.txt
> index 04253c0..191e10e 100644
> --- a/tools/perf/Documentation/perf-report.txt
> +++ b/tools/perf/Documentation/perf-report.txt
> @@ -134,6 +134,11 @@ OPTIONS
> CPUs are specified with -: 0-2. Default is to report samples on all
> CPUs.
>
> +-I::
> +--show-info::
> + Display information about the perf.data file, incl. hostname,
> + os release, perf version, machine desc.
> +
> SEE ALSO
> --------
> linkperf:perf-stat[1]
> diff --git a/tools/perf/Documentation/perf-script.txt b/tools/perf/Documentation/perf-script.txt
> index db01786..ebf8a23 100644
> --- a/tools/perf/Documentation/perf-script.txt
> +++ b/tools/perf/Documentation/perf-script.txt
> @@ -188,6 +188,13 @@ OPTIONS
> CPUs are specified with -: 0-2. Default is to report samples on all
> CPUs.
>
> +-I::
> +--show-info::
> + Display information about the perf.data file, incl. hostname,
> + os release, perf version, machine desc. It can only be used with the
> + perf script report mode and it must be specified after the script name
> + like for instance: perf script report syscall-counts -I.
> +
> SEE ALSO
> --------
> linkperf:perf-record[1], linkperf:perf-script-perl[1],
> diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
> index 6b0519f..524ebbf 100644
> --- a/tools/perf/builtin-record.c
> +++ b/tools/perf/builtin-record.c
> @@ -513,6 +513,18 @@ static int __cmd_record(int argc, const char **argv)
> if (have_tracepoints(&evsel_list->entries))
> perf_header__set_feat(&session->header, HEADER_TRACE_INFO);
>
> + perf_header__set_feat(&session->header, HEADER_HOSTNAME);
> + perf_header__set_feat(&session->header, HEADER_OSRELEASE);
> + perf_header__set_feat(&session->header, HEADER_ARCH);
> + perf_header__set_feat(&session->header, HEADER_CPUID);
> + perf_header__set_feat(&session->header, HEADER_NRCPUS);
> + perf_header__set_feat(&session->header, HEADER_EVENT_DESC);
> + perf_header__set_feat(&session->header, HEADER_CMDLINE);
> + perf_header__set_feat(&session->header, HEADER_VERSION);
> + perf_header__set_feat(&session->header, HEADER_CPU_TOPOLOGY);
> + perf_header__set_feat(&session->header, HEADER_TOTAL_MEM);
> + perf_header__set_feat(&session->header, HEADER_NUMA_TOPOLOGY);
> +
> /* 512 kiB: default amount of unprivileged mlocked memory */
> if (mmap_pages == UINT_MAX)
> mmap_pages = (512 * 1024) / page_size;
> @@ -782,6 +794,8 @@ int cmd_record(int argc, const char **argv, const char *prefix __used)
> int err = -ENOMEM;
> struct perf_evsel *pos;
>
> + perf_header__set_cmdline(argc, argv);
> +
> evsel_list = perf_evlist__new(NULL, NULL);
> if (evsel_list == NULL)
> return -ENOMEM;
> diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
> index d7ff277..7721030 100644
> --- a/tools/perf/builtin-report.c
> +++ b/tools/perf/builtin-report.c
> @@ -40,6 +40,7 @@ static char const *input_name = "perf.data";
> static bool force, use_tui, use_stdio;
> static bool hide_unresolved;
> static bool dont_use_callchains;
> +static bool show_info;
>
> static bool show_threads;
> static struct perf_read_values show_threads_values;
> @@ -276,6 +277,9 @@ static int __cmd_report(void)
> goto out_delete;
> }
>
> + if (show_info)
> + perf_session__fprintf_info(session, stdout);
> +
> if (show_threads)
> perf_read_values_init(&show_threads_values);
>
> @@ -487,6 +491,8 @@ static const struct option options[] = {
> OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
> "Look for files with symbols relative to this directory"),
> OPT_STRING('c', "cpu", &cpu_list, "cpu", "list of cpus to profile"),
> + OPT_BOOLEAN('I', "show-info", &show_info,
> + "display information about perf.data file"),
> OPT_END()
> };
>
> diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
> index 09024ec..dac86ab 100644
> --- a/tools/perf/builtin-script.c
> +++ b/tools/perf/builtin-script.c
> @@ -22,6 +22,7 @@ static u64 last_timestamp;
> static u64 nr_unordered;
> extern const struct option record_options[];
> static bool no_callchain;
> +static bool show_info = false;
> static const char *cpu_list;
> static DECLARE_BITMAP(cpu_bitmap, MAX_NR_CPUS);
>
> @@ -1083,7 +1084,8 @@ static const struct option options[] = {
> "comma separated output fields prepend with 'type:'. Valid types: hw,sw,trace,raw. Fields: comm,tid,pid,time,cpu,event,trace,ip,sym,dso,addr",
> parse_output_fields),
> OPT_STRING('c', "cpu", &cpu_list, "cpu", "list of cpus to profile"),
> -
> + OPT_BOOLEAN('I', "show-info", &show_info,
> + "display host information from perf.data file"),
> OPT_END()
> };
>
> @@ -1268,6 +1270,9 @@ int cmd_script(int argc, const char **argv, const char *prefix __used)
> return -1;
> }
>
> + if (show_info)
> + perf_session__fprintf_info(session, stdout);
> +
> if (!no_callchain)
> symbol_conf.use_callchain = true;
> else
> diff --git a/tools/perf/builtin.h b/tools/perf/builtin.h
> index 4702e24..b382bd5 100644
> --- a/tools/perf/builtin.h
> +++ b/tools/perf/builtin.h
> @@ -4,7 +4,6 @@
> #include "util/util.h"
> #include "util/strbuf.h"
>
> -extern const char perf_version_string[];
> extern const char perf_usage_string[];
> extern const char perf_more_info_string[];
>
> diff --git a/tools/perf/perf.h b/tools/perf/perf.h
> index a5fc660..08b0b5e 100644
> --- a/tools/perf/perf.h
> +++ b/tools/perf/perf.h
> @@ -9,18 +9,21 @@ void get_term_dimensions(struct winsize *ws);
> #include "../../arch/x86/include/asm/unistd.h"
> #define rmb() asm volatile("lock; addl $0,0(%%esp)" ::: "memory")
> #define cpu_relax() asm volatile("rep; nop" ::: "memory");
> +#define CPUINFO_PROC "model name"
> #endif
>
> #if defined(__x86_64__)
> #include "../../arch/x86/include/asm/unistd.h"
> #define rmb() asm volatile("lfence" ::: "memory")
> #define cpu_relax() asm volatile("rep; nop" ::: "memory");
> +#define CPUINFO_PROC "model name"
> #endif
>
> #ifdef __powerpc__
> #include "../../arch/powerpc/include/asm/unistd.h"
> #define rmb() asm volatile ("sync" ::: "memory")
> #define cpu_relax() asm volatile ("" ::: "memory");
> +#define CPUINFO_PROC "cpu"
> #endif
>
> #ifdef __s390__
> @@ -37,30 +40,35 @@ void get_term_dimensions(struct winsize *ws);
> # define rmb() asm volatile("" ::: "memory")
> #endif
> #define cpu_relax() asm volatile("" ::: "memory")
> +#define CPUINFO_PROC "cpu type"
> #endif
>
> #ifdef __hppa__
> #include "../../arch/parisc/include/asm/unistd.h"
> #define rmb() asm volatile("" ::: "memory")
> #define cpu_relax() asm volatile("" ::: "memory");
> +#define CPUINFO_PROC "cpu"
> #endif
>
> #ifdef __sparc__
> #include "../../arch/sparc/include/asm/unistd.h"
> #define rmb() asm volatile("":::"memory")
> #define cpu_relax() asm volatile("":::"memory")
> +#define CPUINFO_PROC "cpu"
> #endif
>
> #ifdef __alpha__
> #include "../../arch/alpha/include/asm/unistd.h"
> #define rmb() asm volatile("mb" ::: "memory")
> #define cpu_relax() asm volatile("" ::: "memory")
> +#define CPUINFO_PROC "cpu model"
> #endif
>
> #ifdef __ia64__
> #include "../../arch/ia64/include/asm/unistd.h"
> #define rmb() asm volatile ("mf" ::: "memory")
> #define cpu_relax() asm volatile ("hint @pause" ::: "memory")
> +#define CPUINFO_PROC "model name"
> #endif
>
> #ifdef __arm__
> @@ -71,6 +79,7 @@ void get_term_dimensions(struct winsize *ws);
> */
> #define rmb() ((void(*)(void))0xffff0fa0)()
> #define cpu_relax() asm volatile("":::"memory")
> +#define CPUINFO_PROC "Processor"
> #endif
>
> #ifdef __mips__
> @@ -83,6 +92,7 @@ void get_term_dimensions(struct winsize *ws);
> : /* no input */ \
> : "memory")
> #define cpu_relax() asm volatile("" ::: "memory")
> +#define CPUINFO_PROC "cpu model"
> #endif
>
> #include <time.h>
> @@ -171,5 +181,6 @@ struct ip_callchain {
> };
>
> extern bool perf_host, perf_guest;
> +extern const char perf_version_string[];
>
> #endif
> diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
> index b6c1ad1..73fa59e 100644
> --- a/tools/perf/util/header.c
> +++ b/tools/perf/util/header.c
> @@ -7,6 +7,7 @@
> #include <stdlib.h>
> #include <linux/list.h>
> #include <linux/kernel.h>
> +#include <sys/utsname.h>
>
> #include "evlist.h"
> #include "evsel.h"
> @@ -17,12 +18,19 @@
> #include "session.h"
> #include "symbol.h"
> #include "debug.h"
> +#include "cpumap.h"
>
> static bool no_buildid_cache = false;
>
> static int event_count;
> static struct perf_trace_event_type *events;
>
> +static u32 header_argc;
> +static const char **header_argv;
> +
> +static int dsos__write_buildid_table(struct perf_header *header, int fd);
> +static int perf_session__cache_build_ids(struct perf_session *session);
> +
> int perf_header__push_event(u64 id, const char *name)
> {
> if (strlen(name) > MAX_EVENT_NAME)
> @@ -110,6 +118,843 @@ static int write_padded(int fd, const void *bf, size_t count,
> return err;
> }
>
> +static int do_write_string(int fd, const char *str)
> +{
> + u32 len, olen;
> + int ret;
> +
> + olen = strlen(str) + 1;
> + len = ALIGN(olen, NAME_ALIGN);
> +
> + /* write len, incl. \0 */
> + ret = do_write(fd, &len, sizeof(len));
> + if (ret < 0)
> + return ret;
> +
> + return write_padded(fd, str, olen, len);
> +}
> +
> +static char *do_read_string(int fd, struct perf_header *ph)
> +{
> + ssize_t sz, ret;
> + u32 len;
> + char *buf;
> +
> + sz = read(fd, &len, sizeof(len));
> + if (sz < (ssize_t)sizeof(len))
> + return NULL;
> +
> + if (ph->needs_swap)
> + len = bswap_32(len);
> +
> + buf = malloc(len);
> + if (!buf)
> + return NULL;
> +
> + ret = read(fd, buf, len);
> + if (ret == (ssize_t)len) {
> + /*
> + * strings are padded by zeroes
> + * thus the actual strlen of buf
> + * may be less than len
> + */
> + return buf;
> + }
> +
> + free(buf);
> + return NULL;
> +}
> +
> +int
> +perf_header__set_cmdline(int argc, const char **argv)
> +{
> + int i;
> +
> + header_argc = (u32)argc;
> +
> + /* do not include NULL termination */
> + header_argv = calloc(argc, sizeof(char *));
> + if (!header_argv)
> + return -ENOMEM;
> +
> + /*
> + * must copy argv contents because it gets moved
> + * around during option parsing
> + */
> + for (i = 0; i < argc ; i++)
> + header_argv[i] = argv[i];
> +
> + return 0;
> +}
> +
> +static int write_trace_info(int fd, struct perf_header *h __used,
> + struct perf_evlist *evlist)
> +{
> + return read_tracing_data(fd, &evlist->entries);
> +}
> +
> +
> +static int write_build_id(int fd, struct perf_header *h,
> + struct perf_evlist *evlist __used)
> +{
> + struct perf_session *session;
> + int err;
> +
> + session = container_of(h, struct perf_session, header);
> +
> + err = dsos__write_buildid_table(h, fd);
> + if (err < 0) {
> + pr_debug("failed to write buildid table\n");
> + return err;
> + }
> + if (!no_buildid_cache)
> + perf_session__cache_build_ids(session);
> +
> + return 0;
> +}
> +
> +static int write_hostname(int fd, struct perf_header *h __used,
> + struct perf_evlist *evlist __used)
> +{
> + struct utsname uts;
> + int ret;
> +
> + ret = uname(&uts);
> + if (ret < 0)
> + return -1;
> +
> + return do_write_string(fd, uts.nodename);
> +}
> +
> +static int write_osrelease(int fd, struct perf_header *h __used,
> + struct perf_evlist *evlist __used)
> +{
> + struct utsname uts;
> + int ret;
> +
> + ret = uname(&uts);
> + if (ret < 0)
> + return -1;
> +
> + return do_write_string(fd, uts.release);
> +}
> +
> +static int write_arch(int fd, struct perf_header *h __used,
> + struct perf_evlist *evlist __used)
> +{
> + struct utsname uts;
> + int ret;
> +
> + ret = uname(&uts);
> + if (ret < 0)
> + return -1;
> +
> + return do_write_string(fd, uts.machine);
> +}
> +
> +static int write_version(int fd, struct perf_header *h __used,
> + struct perf_evlist *evlist __used)
> +{
> + return do_write_string(fd, perf_version_string);
> +}
> +
> +static int write_cpuid(int fd, struct perf_header *h __used,
> + struct perf_evlist *evlist __used)
> +{
> +#ifndef CPUINFO_PROC
> +#define CPUINFO_PROC NULL
> +#endif
> + FILE *file;
> + char buf[256];
> + char *s, *p;
> + const char *search = CPUINFO_PROC;
> +
> + file = fopen("/proc/cpuinfo", "r");
> + if (!file)
> + return -1;
> +
> + if (search) {
> + while (fgets(buf, sizeof(buf), file)) {
> + if (strstr(buf, search))
> + goto found;
> + }
> + }
> + strcpy(buf, "unknown type");
> +found:
> + fclose(file);
> +
> + s = buf;
> +
> + p = strchr(buf, ':');
> + if (p && *(p+1) == ' ' && *(p+2))
> + s = p + 2;
> + p = strchr(s, '\n');
> + if (p)
> + *p = '\0';
> +
> + /* squash extra space characters (branding string) */
> + p = s;
> + while (*p) {
> + if (isspace(*p)) {
> + char *r = p + 1;
> + char *q = r;
> + *p = ' ';
> + while (*q && isspace(*q))
> + q++;
> + if (q != (p+1))
> + while ((*r++ = *q++));
> + }
> + p++;
> + }
> + return do_write_string(fd, s);
> +}
> +
> +static int write_nrcpus(int fd, struct perf_header *h __used,
> + struct perf_evlist *evlist __used)
> +{
> + long nr;
> + u32 nrc, nra;
> + int ret;
> +
> + nr = sysconf(_SC_NPROCESSORS_CONF);
> + if (nr < 0)
> + return -1;
> +
> + nrc = (u32)(nr & UINT_MAX);
> +
> + ret = sysconf(_SC_NPROCESSORS_ONLN);
> + if (ret < 0)
> + return -1;
> +
> + nra = (u32)(nr & UINT_MAX);
> +
> + ret = do_write(fd, &nrc, sizeof(nrc));
> + if (ret < 0)
> + return ret;
> +
> + return do_write(fd, &nra, sizeof(nra));
> +}
> +
> +static int write_event_desc(int fd, struct perf_header *h __used,
> + struct perf_evlist *evlist)
> +{
> + struct perf_evsel *attr;
> + u32 nre = 0, nri, sz;
> + int ret;
> +
> + list_for_each_entry(attr, &evlist->entries, node)
> + nre++;
> +
> + /*
> + * write number of events
> + */
> + ret = do_write(fd, &nre, sizeof(nre));
> + if (ret < 0)
> + return ret;
> +
> + /*
> + * size of perf_event_attr struct
> + */
> + sz = (u32)sizeof(attr->attr);
> + ret = do_write(fd, &sz, sizeof(sz));
> + if (ret < 0)
> + return ret;
> +
> + list_for_each_entry(attr, &evlist->entries, node) {
> +
> + ret = do_write(fd, &attr->attr, sz);
> + if (ret < 0)
> + return ret;
> + /*
> + * write number of unique id per event
> + * there is one id per instance of an event
> + *
> + * copy into an nri to be independent of the
> + * type of ids,
> + */
> + nri = attr->ids;
> + ret = do_write(fd, &nri, sizeof(nri));
> + if (ret < 0)
> + return ret;
> +
> + /*
> + * write event string as passed on cmdline
> + */
> + ret = do_write_string(fd, attr->name);
> + if (ret < 0)
> + return ret;
> + /*
> + * write unique ids for this event
> + */
> + ret = do_write(fd, attr->id, attr->ids * sizeof(u64));
> + if (ret < 0)
> + return ret;
> + }
> + return 0;
> +}
> +
> +static int write_cmdline(int fd, struct perf_header *h __used,
> + struct perf_evlist *evlist __used)
> +{
> + char buf[MAXPATHLEN];
> + char proc[32];
> + u32 i, n;
> + int ret;
> +
> + /*
> + * actual atual path to perf binary
> + */
> + sprintf(proc, "/proc/%d/exe", getpid());
> + ret = readlink(proc, buf, sizeof(buf));
> + if (ret <= 0)
> + return -1;
> +
> + /* readlink() does not add null termination */
> + buf[ret] = '\0';
> +
> + /* account for binary path */
> + n = header_argc + 1;
> +
> + ret = do_write(fd, &n, sizeof(n));
> + if (ret < 0)
> + return ret;
> +
> + ret = do_write_string(fd, buf);
> + if (ret < 0)
> + return ret;
> +
> + for (i = 0 ; i < header_argc; i++) {
> + ret = do_write_string(fd, header_argv[i]);
> + if (ret < 0)
> + return ret;
> + }
> + return 0;
> +}
> +
> +static const char *topo_fmt[] = {
> + "/sys/devices/system/cpu/cpu%d/topology/core_siblings_list",
> + "/sys/devices/system/cpu/cpu%d/topology/thread_siblings_list",
> + NULL
> +};
> +
> +static int write_topo_cpu(int fd, int cpu)
> +{
> + FILE *fp;
> + char filename[MAXPATHLEN];
> + char buf[MAXPATHLEN], *p, *c;
> + const char **q = topo_fmt;
> + int ret;
> +
> + while (*q) {
> +
> + sprintf(filename, *q, cpu);
> +
> + fp = fopen(filename, "r");
> + if (!fp)
> + return -1;
> +
> + c = fgets(buf, sizeof(buf), fp);
> + if (!c) {
> + fclose(fp);
> + return -1;
> + }
> +
> + p = strchr(buf, '\n');
> + if (p)
> + *p = '\0';
> +
> + fclose(fp);
> +
> + ret = do_write_string(fd, c);
> + if (ret < 0)
> + return ret;
> + q++;
> + }
> + return 0;
> +}
> +
> +static int write_cpu_topology(int fd, struct perf_header *h __used,
> + struct perf_evlist *evlist __used)
> +{
> + u32 nr, i;
> + long ncpus;
> + int ret;
> +
> + ncpus = sysconf(_SC_NPROCESSORS_CONF);
> + if (ncpus < 0)
> + return -1;
> +
> + /* hopefully, this will keep compilers happy about the cast */
> + nr = (u32)(ncpus & UINT_MAX);
> +
> + ret = do_write(fd, &nr, sizeof(nr));
> + if (ret < 0)
> + return -1;
> +
> + for (i = 0; i < nr; i++) {
> + ret = do_write(fd, &i, sizeof(i));
> + if (ret < 0)
> + return ret;
> +
> + ret = write_topo_cpu(fd, i);
> + if (ret < 0)
> + return ret;
> + }
> + return 0;
> +}
> +
> +static int write_total_mem(int fd, struct perf_header *h __used,
> + struct perf_evlist *evlist __used)
> +{
> + char buf[MAXPATHLEN], *c;
> + FILE *fp;
> + int ret = -1, n;
> + uint64_t mem;
> +
> + fp = fopen("/proc/meminfo", "r");
> + if (!fp)
> + return -1;
> +
> + while ((c = fgets(buf, sizeof(buf), fp))) {
> + c = strstr(buf, "MemTotal:");
> + if (c)
> + break;
> + }
> + fclose(fp);
> +
> + n = sscanf(buf, "%*s %"PRIu64, &mem);
> + if (n == 1)
> + ret = do_write(fd, &mem, sizeof(mem));
> +
> + return ret;
> +}
> +
> +static int write_topo_node(int fd, int node)
> +{
> + char filename[MAXPATHLEN];
> + char buf[MAXPATHLEN], *p, *c;
> + FILE *fp;
> + uint64_t mem;
> + int ret;
> +
> + sprintf(filename, "/sys/devices/system/node/node%d/meminfo", node);
> + fp = fopen(filename, "r");
> + if (!fp)
> + return -1;
> +
> + while ((c = fgets(buf, sizeof(buf), fp))) {
> + c = strstr(buf, "MemTotal:");
> + if (c)
> + break;
> + }
> + fclose(fp);
> + if (!c)
> + return -1;
> + ret = sscanf(buf, "%*s %*d %*s %"PRIu64, &mem);
> + if (ret != 1)
> + return -1;
> +
> + ret = do_write(fd, &mem, sizeof(mem));
> + if (ret < 0)
> + return -1;
> +
> + sprintf(filename, "/sys/devices/system/node/node%d/cpulist", node);
> + fp = fopen(filename, "r");
> + if (!fp)
> + return -1;
> +
> + c = fgets(buf, sizeof(buf), fp);
> + fclose(fp);
> + if (!c)
> + return -1;
> +
> + p = strchr(buf, '\n');
> + if (p)
> + *p = '\0';
> +
> + return do_write_string(fd, c);
> +}
> +
> +static int write_numa_topology(int fd, struct perf_header *h __used,
> + struct perf_evlist *evlist __used)
> +{
> + char buf[MAXPATHLEN];
> + FILE *fp;
> + struct cpu_map *node_map;
> + char *c;
> + u32 nr, i, j;
> + int ret;
> +
> + fp = fopen("/sys/devices/system/node/online", "r");
> + if (!fp)
> + return -1;
> +
> + c = fgets(buf, sizeof(buf), fp);
> + fclose(fp);
> + if (!c)
> + return -1;
> +
> + c = strchr(buf, '\n');
> + if (c)
> + *c = '\0';
> +
> + node_map = cpu_map__new(buf);
> + if (!node_map)
> + return -1;
> +
> + nr = (u32)node_map->nr;
> + ret = do_write(fd, &nr, sizeof(nr));
> + if (ret < 0)
> + return -1;
> +
> + for (i = 0; i < nr; i++) {
> + j = (u32)node_map->map[i];
> + ret = do_write(fd, &j, sizeof(j));
> + if (ret < 0)
> + goto error;
> +
> + ret = write_topo_node(fd, i);
> + if (ret < 0)
> + goto error;
> + }
> + ret = 0;
> +error:
> + free(node_map);
> + return ret;
> +}
> +
> +static void print_hostname(struct perf_header *ph, int fd, FILE *fp)
> +{
> + char *str = do_read_string(fd, ph);
> + fprintf(fp, "# hostname : %s\n", str);
> + free(str);
> +}
> +
> +static void print_osrelease(struct perf_header *ph, int fd, FILE *fp)
> +{
> + char *str = do_read_string(fd, ph);
> + fprintf(fp, "# os release : %s\n", str);
> + free(str);
> +}
> +
> +static void print_arch(struct perf_header *ph, int fd, FILE *fp)
> +{
> + char *str = do_read_string(fd, ph);
> + fprintf(fp, "# arch : %s\n", str);
> + free(str);
> +}
> +
> +static void print_cpuid(struct perf_header *ph, int fd, FILE *fp)
> +{
> + char *str = do_read_string(fd, ph);
> + fprintf(fp, "# cpuid : %s\n", str);
> + free(str);
> +}
> +
> +static void print_nrcpus(struct perf_header *ph, int fd, 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);
> +}
> +
> +static void print_version(struct perf_header *ph, int fd, FILE *fp)
> +{
> + char *str = do_read_string(fd, ph);
> + fprintf(fp, "# perf version : %s\n", str);
> + free(str);
> +}
> +
> +static void print_cmdline(struct perf_header *ph, int fd, FILE *fp)
> +{
> + ssize_t ret;
> + char *str;
> + u32 nr, i;
> +
> + ret = read(fd, &nr, sizeof(nr));
> + if (ret != (ssize_t)sizeof(nr)) {
> + fprintf(fp, "# cmdline : unknown\n");
> + return;
> + }
> +
> + if (ph->needs_swap)
> + nr = bswap_32(nr);
> +
> + fprintf(fp, "# cmdline : ");
> +
> + for (i = 0; i < nr; i++) {
> + str = do_read_string(fd, ph);
> + fprintf(fp, "%s ", str);
> + free(str);
> + }
> + fputc('\n', fp);
> +}
> +
> +static void print_cpu_topology(struct perf_header *ph, int fd, FILE *fp)
> +{
> + ssize_t ret;
> + u32 nr, c, i;
> + char *str;
> +
> + ret = read(fd, &nr, sizeof(nr));
> + if (ret != (ssize_t)sizeof(nr)) {
> + fprintf(fp, "# cpu topology : not available\n");
> + return;
> + }
> +
> + if (ph->needs_swap)
> + nr = bswap_32(nr);
> +
> + for (i = 0; i < nr; i++) {
> +
> + ret = read(fd, &c, sizeof(c));
> + if (ret != (ssize_t)sizeof(c))
> + c = -1; /* interpreted as error */
> +
> + if (ph->needs_swap)
> + c = bswap_32(c);
> +
> + str = do_read_string(fd, ph);
> + fprintf(fp, "# CPU%u sibling cores : %s\n", c, str);
> + free(str);
> +
> + str = do_read_string(fd, ph);
> + fprintf(fp, "# CPU%u sibling threads: %s\n", c, str);
> + free(str);
> + }
> +}
> +
> +static void print_event_desc(struct perf_header *ph, int fd, FILE *fp)
> +{
> + struct perf_event_attr attr;
> + uint64_t id;
> + void *buf = NULL;
> + char *str;
> + u32 nre, sz, nr, i, j, msz;
> + int ret;
> +
> + /* number of events */
> + ret = read(fd, &nre, sizeof(nre));
> + if (ret != (ssize_t)sizeof(nre))
> + goto error;
> +
> + if (ph->needs_swap)
> + nre = bswap_32(nre);
> +
> + ret = read(fd, &sz, sizeof(sz));
> + if (ret != (ssize_t)sizeof(sz))
> + goto error;
> +
> + if (ph->needs_swap)
> + sz = bswap_32(sz);
> +
> + /*
> + * ensure it is at least to our ABI rev
> + */
> + if (sz < (u32)sizeof(attr))
> + goto error;
> +
> + memset(&attr, 0, sizeof(attr));
> +
> + /* read entire region to sync up to next field */
> + buf = malloc(sz);
> + if (!buf)
> + goto error;
> +
> + msz = sizeof(attr);
> + if (sz < msz)
> + msz = sz;
> +
> + for (i = 0 ; i < nre; i++) {
> +
> + ret = read(fd, buf, sz);
> + if (ret != (ssize_t)sz)
> + goto error;
> +
> + if (ph->needs_swap)
> + perf_event__attr_swap(buf);
> +
> + memcpy(&attr, buf, msz);
> +
> + ret = read(fd, &nr, sizeof(nr));
> + if (ret != (ssize_t)sizeof(nr))
> + goto error;
> +
> + if (ph->needs_swap)
> + nr = bswap_32(nr);
> +
> + str = do_read_string(fd, ph);
> + fprintf(fp, "# event = %s, ", str);
> + free(str);
> +
> + fprintf(fp, "type = %d, config = 0x%"PRIx64
> + ", config1 = 0x%"PRIx64", config2 = 0x%"PRIx64,
> + attr.type,
> + (u64)attr.config,
> + (u64)attr.config1,
> + (u64)attr.config2);
> +
> + fprintf(fp, ", excl_usr = %d, excl_kern = %d",
> + attr.exclude_user,
> + attr.exclude_kernel);
> +
> + if (nr)
> + fprintf(fp, ", id = {");
> +
> + for (j = 0 ; j < nr; j++) {
> + ret = read(fd, &id, sizeof(id));
> + if (ret != (ssize_t)sizeof(id))
> + goto error;
> +
> + if (ph->needs_swap)
> + id = bswap_64(id);
> +
> + if (j)
> + fputc(',', fp);
> +
> + fprintf(fp, " %"PRIu64, id);
> + }
> + if (nr && j == nr)
> + fprintf(fp, " }");
> + fputc('\n', fp);
> + }
> + free(buf);
> + return;
> +error:
> + fprintf(fp, "# event desc: not available or unable to read\n");
> +}
> +
> +static void print_total_mem(struct perf_header *h __used, int fd, 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");
> +}
> +
> +static void print_numa_topology(struct perf_header *h __used, int fd, FILE *fp)
> +{
> + ssize_t ret;
> + u32 nr, c, i;
> + char *str;
> + uint64_t mem;
> +
> + /* nr nodes */
> + ret = read(fd, &nr, sizeof(nr));
> + if (ret != (ssize_t)sizeof(nr))
> + goto error;
> +
> + if (h->needs_swap)
> + nr = bswap_32(nr);
> +
> + for (i = 0; i < nr; i++) {
> +
> + /* node number */
> + ret = read(fd, &c, sizeof(c));
> + if (ret != (ssize_t)sizeof(c))
> + goto error;
> +
> + if (h->needs_swap)
> + c = bswap_32(c);
> +
> + ret = read(fd, &mem, sizeof(mem));
> + if (ret != sizeof(mem))
> + goto error;
> +
> + if (h->needs_swap)
> + mem = bswap_64(mem);
> +
> + fprintf(fp, "# node%u meminfo : %"PRIu64" kB\n", c, mem);
> +
> + str = do_read_string(fd, h);
> + fprintf(fp, "# node%u cpu list: %s\n", c, str);
> + free(str);
> + }
> + return;
> +error:
> + fprintf(fp, "# numa topology : not available\n");
> +}
> +
> +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);
> +};
> +
> +#define FEAT_OP(n, w, p) [n] = { .write = w, .print = p }
> +
> +static struct feature_ops feat_ops[HEADER_LAST_FEATURE] = {
> + FEAT_OP(HEADER_TRACE_INFO, write_trace_info, NULL),
> + FEAT_OP(HEADER_BUILD_ID, write_build_id, NULL),
> + FEAT_OP(HEADER_HOSTNAME, write_hostname, print_hostname),
> + FEAT_OP(HEADER_OSRELEASE, write_osrelease, print_osrelease),
> + FEAT_OP(HEADER_ARCH, write_arch, print_arch),
> + FEAT_OP(HEADER_CPUID, write_cpuid, print_cpuid),
> + FEAT_OP(HEADER_NRCPUS, write_nrcpus, print_nrcpus),
> + FEAT_OP(HEADER_EVENT_DESC, write_event_desc, print_event_desc),
> + FEAT_OP(HEADER_CMDLINE, write_cmdline, print_cmdline),
> + FEAT_OP(HEADER_VERSION, write_version, print_version),
> + FEAT_OP(HEADER_CPU_TOPOLOGY, write_cpu_topology, print_cpu_topology),
> + FEAT_OP(HEADER_TOTAL_MEM, write_total_mem, print_total_mem),
> + FEAT_OP(HEADER_NUMA_TOPOLOGY, write_numa_topology, print_numa_topology),
> +};
> +
> +static int perf_header_fprintf_info(struct perf_file_section *section,
> + struct perf_header *ph,
> + int feat, int fd, void *data)
> +{
> + FILE *fp = data;
> +
> + if (lseek(fd, section->offset, SEEK_SET) == (off_t)-1) {
> + pr_debug("Failed to lseek to %" PRIu64 " offset for feature "
> + "%d, continuing...\n", section->offset, feat);
> + return 0;
> + }
> + if (feat < HEADER_TRACE_INFO || feat >= HEADER_LAST_FEATURE) {
> + pr_warning("unknown feature %d\n", feat);
> + return -1;
> + }
> +
> + if (feat_ops[feat].print)
> + feat_ops[feat].print(ph, fd, fp);
> +
> + return 0;
> +}
> +
> +int perf_header__fprintf_info(struct perf_session *session, FILE *fp __used)
> +{
> + int fd = session->fd;
> + struct perf_header *header = &session->header;
> + perf_header__process_sections(header, fd, fp, perf_header_fprintf_info);
> + return 0;
> +}
> +
> #define dsos__for_each_with_build_id(pos, head) \
> list_for_each_entry(pos, head, node) \
> if (!pos->has_build_id) \
> @@ -356,15 +1201,41 @@ static bool perf_session__read_build_ids(struct perf_session *session, bool with
> return ret;
> }
>
> +static int do_write_feat(int fd, struct perf_header *h, int type,
> + struct perf_file_section **p,
> + struct perf_evlist *evlist)
> +{
> + int err;
> + int ret = 0;
> +
> + if (perf_header__has_feat(h, type)) {
> +
> + (*p)->offset = lseek(fd, 0, SEEK_CUR);
> +
> + err = feat_ops[type].write(fd, h, evlist);
> + if (err < 0) {
> + pr_debug("failed to write feature %d\n", type);
> +
> + /* undo anything written */
> + lseek(fd, (*p)->offset, SEEK_SET);
> +
> + return -1;
> + }
> + (*p)->size = lseek(fd, 0, SEEK_CUR) - (*p)->offset;
> + (*p)++;
> + }
> + return ret;
> +}
> +
> static int perf_header__adds_write(struct perf_header *header,
> struct perf_evlist *evlist, int fd)
> {
> int nr_sections;
> struct perf_session *session;
> - struct perf_file_section *feat_sec;
> + struct perf_file_section *feat_sec, *p;
> int sec_size;
> u64 sec_start;
> - int idx = 0, err;
> + int err;
>
> session = container_of(header, struct perf_session, header);
>
> @@ -376,7 +1247,7 @@ static int perf_header__adds_write(struct perf_header *header,
> if (!nr_sections)
> return 0;
>
> - feat_sec = calloc(sizeof(*feat_sec), nr_sections);
> + feat_sec = p = calloc(sizeof(*feat_sec), nr_sections);
> if (feat_sec == NULL)
> return -ENOMEM;
>
> @@ -385,36 +1256,65 @@ static int perf_header__adds_write(struct perf_header *header,
> sec_start = header->data_offset + header->data_size;
> lseek(fd, sec_start + sec_size, SEEK_SET);
>
> - if (perf_header__has_feat(header, HEADER_TRACE_INFO)) {
> - struct perf_file_section *trace_sec;
> -
> - trace_sec = &feat_sec[idx++];
> + err = do_write_feat(fd, header, HEADER_TRACE_INFO, &p, evlist);
> + if (err)
> + goto out_free;
>
> - /* Write trace info */
> - trace_sec->offset = lseek(fd, 0, SEEK_CUR);
> - read_tracing_data(fd, &evlist->entries);
> - trace_sec->size = lseek(fd, 0, SEEK_CUR) - trace_sec->offset;
> + err = do_write_feat(fd, header, HEADER_BUILD_ID, &p, evlist);
> + if (err) {
> + perf_header__clear_feat(header, HEADER_BUILD_ID);
> + goto out_free;
> }
>
> - if (perf_header__has_feat(header, HEADER_BUILD_ID)) {
> - struct perf_file_section *buildid_sec;
> + err = do_write_feat(fd, header, HEADER_HOSTNAME, &p, evlist);
> + if (err)
> + perf_header__clear_feat(header, HEADER_HOSTNAME);
>
> - buildid_sec = &feat_sec[idx++];
> + err = do_write_feat(fd, header, HEADER_OSRELEASE, &p, evlist);
> + if (err)
> + perf_header__clear_feat(header, HEADER_OSRELEASE);
>
> - /* Write build-ids */
> - buildid_sec->offset = lseek(fd, 0, SEEK_CUR);
> - err = dsos__write_buildid_table(header, fd);
> - if (err < 0) {
> - pr_debug("failed to write buildid table\n");
> - goto out_free;
> - }
> - buildid_sec->size = lseek(fd, 0, SEEK_CUR) -
> - buildid_sec->offset;
> - if (!no_buildid_cache)
> - perf_session__cache_build_ids(session);
> - }
> + err = do_write_feat(fd, header, HEADER_ARCH, &p, evlist);
> + if (err)
> + perf_header__clear_feat(header, HEADER_ARCH);
> +
> + err = do_write_feat(fd, header, HEADER_CPUID, &p, evlist);
> + if (err)
> + perf_header__clear_feat(header, HEADER_CPUID);
> +
> + err = do_write_feat(fd, header, HEADER_NRCPUS, &p, evlist);
> + if (err)
> + perf_header__clear_feat(header, HEADER_NRCPUS);
> +
> + err = do_write_feat(fd, header, HEADER_EVENT_DESC, &p, evlist);
> + if (err)
> + perf_header__clear_feat(header, HEADER_EVENT_DESC);
> +
> + err = do_write_feat(fd, header, HEADER_CMDLINE, &p, evlist);
> + if (err)
> + perf_header__clear_feat(header, HEADER_CMDLINE);
> +
> + err = do_write_feat(fd, header, HEADER_VERSION, &p, evlist);
> + if (err)
> + perf_header__clear_feat(header, HEADER_VERSION);
> +
> + err = do_write_feat(fd, header, HEADER_CPU_TOPOLOGY, &p, evlist);
> + if (err)
> + perf_header__clear_feat(header, HEADER_CPU_TOPOLOGY);
> +
> + err = do_write_feat(fd, header, HEADER_TOTAL_MEM, &p, evlist);
> + if (err)
> + perf_header__clear_feat(header, HEADER_TOTAL_MEM);
> +
> + err = do_write_feat(fd, header, HEADER_NUMA_TOPOLOGY, &p, evlist);
> + if (err)
> + perf_header__clear_feat(header, HEADER_NUMA_TOPOLOGY);
>
> lseek(fd, sec_start, SEEK_SET);
> + /*
> + * may write more than needed due to dropped feature, but
> + * this is okay, reader will skip the mising entries
> + */
> err = do_write(fd, feat_sec, sec_size);
> if (err < 0)
> pr_debug("failed to write feature section\n");
> @@ -554,9 +1454,10 @@ static int perf_header__getbuffer64(struct perf_header *header,
> }
>
> int perf_header__process_sections(struct perf_header *header, int fd,
> + void *data,
> int (*process)(struct perf_file_section *section,
> - struct perf_header *ph,
> - int feat, int fd))
> + struct perf_header *ph,
> + int feat, int fd, void *data))
> {
> struct perf_file_section *feat_sec;
> int nr_sections;
> @@ -584,7 +1485,7 @@ int perf_header__process_sections(struct perf_header *header, int fd,
> if (perf_header__has_feat(header, feat)) {
> struct perf_file_section *sec = &feat_sec[idx++];
>
> - err = process(sec, header, feat, fd);
> + err = process(sec, header, feat, fd, data);
> if (err < 0)
> break;
> }
> @@ -796,7 +1697,7 @@ out:
>
> static int perf_file_section__process(struct perf_file_section *section,
> struct perf_header *ph,
> - int feat, int fd)
> + int feat, int fd, void *data __used)
> {
> if (lseek(fd, section->offset, SEEK_SET) == (off_t)-1) {
> pr_debug("Failed to lseek to %" PRIu64 " offset for feature "
> @@ -935,7 +1836,8 @@ int perf_session__read_header(struct perf_session *session, int fd)
> event_count = f_header.event_types.size / sizeof(struct perf_trace_event_type);
> }
>
> - perf_header__process_sections(header, fd, perf_file_section__process);
> + perf_header__process_sections(header, fd, NULL,
> + perf_file_section__process);
>
> lseek(fd, header->data_offset, SEEK_SET);
>
> diff --git a/tools/perf/util/header.h b/tools/perf/util/header.h
> index 1886256..455480b 100644
> --- a/tools/perf/util/header.h
> +++ b/tools/perf/util/header.h
> @@ -12,6 +12,19 @@
> enum {
> HEADER_TRACE_INFO = 1,
> HEADER_BUILD_ID,
> +
> + HEADER_HOSTNAME,
> + HEADER_OSRELEASE,
> + HEADER_ARCH,
> + HEADER_CPUID,
> + HEADER_NRCPUS,
> + HEADER_EVENT_DESC,
> + HEADER_CMDLINE,
> + HEADER_VERSION,
> + HEADER_CPU_TOPOLOGY,
> + HEADER_TOTAL_MEM,
> + HEADER_NUMA_TOPOLOGY,
> +
> HEADER_LAST_FEATURE,
> };
>
> @@ -68,10 +81,15 @@ void perf_header__set_feat(struct perf_header *header, int feat);
> void perf_header__clear_feat(struct perf_header *header, int feat);
> bool perf_header__has_feat(const struct perf_header *header, int feat);
>
> +int perf_header__set_cmdline(int argc, const char **argv);
> +
> int perf_header__process_sections(struct perf_header *header, int fd,
> + void *data,
> int (*process)(struct perf_file_section *section,
> - struct perf_header *ph,
> - int feat, int fd));
> + struct perf_header *ph,
> + int feat, int fd, void *data));
> +
> +int perf_header__fprintf_info(struct perf_session *session, FILE *fp);
>
> int build_id_cache__add_s(const char *sbuild_id, const char *debugdir,
> const char *name, bool is_kallsyms);
> diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
> index 72458d9..54613a2 100644
> --- a/tools/perf/util/session.c
> +++ b/tools/perf/util/session.c
> @@ -1326,3 +1326,21 @@ int perf_session__cpu_bitmap(struct perf_session *session,
>
> return 0;
> }
> +
> +void perf_session__fprintf_info(struct perf_session *session, FILE *fp)
> +{
> + struct stat st;
> + int ret;
> +
> + if (session == NULL || fp == NULL)
> + return;
> +
> + ret = fstat(session->fd, &st);
> + if (ret == -1)
> + return;
> +
> + fprintf(fp, "#\n# captured on: %s", ctime(&st.st_ctime));
> + ret = perf_header__fprintf_info(session, fp);
> + if (ret == 0)
> + fprintf(fp, "#\n");
> +}
> diff --git a/tools/perf/util/session.h b/tools/perf/util/session.h
> index 170601e..33a3a46 100644
> --- a/tools/perf/util/session.h
> +++ b/tools/perf/util/session.h
> @@ -176,4 +176,5 @@ void perf_session__print_ip(union perf_event *event,
> int perf_session__cpu_bitmap(struct perf_session *session,
> const char *cpu_list, unsigned long *cpu_bitmap);
>
> +void perf_session__fprintf_info(struct perf_session *session, FILE *fp);
> #endif /* __PERF_SESSION_H */
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