Merge branch 'linus' into tracing/urgent

Merge reason: Merge up to almost-rc6 to pick up latest perfcounters
              (on which we'll queue up a dependent fix)

Signed-off-by: Ingo Molnar <mingo@elte.hu>

6 files changed, 189 insertions, 18 deletions

diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt
index 1dbc1eeb4c01..6be696b0a2bb 100644
--- a/tools/perf/Documentation/perf-record.txt
+++ b/tools/perf/Documentation/perf-record.txt
@@ -29,13 +29,67 @@ OPTIONS
         Select the PMU event. Selection can be a symbolic event name
         (use 'perf list' to list all events) or a raw PMU
         event (eventsel+umask) in the form of rNNN where NNN is a
-         hexadecimal event descriptor.
+        hexadecimal event descriptor.
 
 -a::
-        system-wide collection
+        System-wide collection.
 
 -l::
-        scale counter values
+        Scale counter values.
+
+-p::
+--pid=::
+        Record events on existing pid.
+
+-r::
+--realtime=::
+        Collect data with this RT SCHED_FIFO priority.
+-A::
+--append::
+        Append to the output file to do incremental profiling.
+
+-f::
+--force::
+        Overwrite existing data file.
+
+-c::
+--count=::
+        Event period to sample.
+
+-o::
+--output=::
+        Output file name.
+
+-i::
+--inherit::
+        Child tasks inherit counters.
+-F::
+--freq=::
+        Profile at this frequency.
+
+-m::
+--mmap-pages=::
+        Number of mmap data pages.
+
+-g::
+--call-graph::
+        Do call-graph (stack chain/backtrace) recording.
+
+-v::
+--verbose::
+        Be more verbose (show counter open errors, etc).
+
+-s::
+--stat::
+        Per thread counts.
+
+-d::
+--data::
+        Sample addresses.
+
+-n::
+--no-samples::
+        Don't sample.
 
 SEE ALSO
 --------
diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index a5e9b876ca09..1916e44b9bb0 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -158,8 +158,10 @@ uname_P := $(shell sh -c 'uname -p 2>/dev/null || echo not')
 uname_V := $(shell sh -c 'uname -v 2>/dev/null || echo not')
 
 # If we're on a 64-bit kernel, use -m64
-ifneq ($(patsubst %64,%,$(uname_M)),$(uname_M))
-  M64 := -m64
+ifndef NO_64BIT
+        ifneq ($(patsubst %64,%,$(uname_M)),$(uname_M))
+          M64 := -m64
+        endif
 endif
 
 # CFLAGS and LDFLAGS are for the users to override from the command line.
@@ -345,7 +347,6 @@ BUILTIN_OBJS += builtin-stat.o
 BUILTIN_OBJS += builtin-top.o
 
 PERFLIBS = $(LIB_FILE)
-EXTLIBS = -lbfd
 
 #
 # Platform specific tweaks
@@ -374,6 +375,28 @@ ifeq ($(uname_S),Darwin)
         PTHREAD_LIBS =
 endif
 
+ifneq ($(shell sh -c "(echo '\#include <libelf.h>'; echo 'int main(void) { Elf * elf = elf_begin(0, ELF_C_READ_MMAP, 0); return (long)elf; }') | $(CC) -x c - $(ALL_CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -o /dev/null $(ALL_LDFLAGS) > /dev/null 2>&1 && echo y"), y)
+        msg := $(error No libelf.h/libelf found, please install libelf-dev/elfutils-libelf-devel);
+endif
+
+ifdef NO_DEMANGLE
+        BASIC_CFLAGS += -DNO_DEMANGLE
+else
+
+        has_bfd := $(shell sh -c "(echo '\#include <bfd.h>'; echo 'int main(void) { bfd_demangle(0, 0, 0); return 0; }') | $(CC) -x c - $(ALL_CFLAGS) -o /dev/null $(ALL_LDFLAGS) -lbfd > /dev/null 2>&1 && echo y")
+
+        has_bfd_iberty := $(shell sh -c "(echo '\#include <bfd.h>'; echo 'int main(void) { bfd_demangle(0, 0, 0); return 0; }') | $(CC) -x c - $(ALL_CFLAGS) -o /dev/null $(ALL_LDFLAGS) -lbfd -liberty > /dev/null 2>&1 && echo y")
+
+        ifeq ($(has_bfd),y)
+                EXTLIBS += -lbfd
+        else ifeq ($(has_bfd_iberty),y)
+                EXTLIBS += -lbfd -liberty
+        else
+                msg := $(warning No bfd.h/libbfd found, install binutils-dev[el] to gain symbol demangling)
+                BASIC_CFLAGS += -DNO_DEMANGLE
+        endif
+endif
+
 ifndef CC_LD_DYNPATH
         ifdef NO_R_TO_GCC_LINKER
                 # Some gcc does not accept and pass -R to the linker to specify
diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index b20a4b6e31b7..8cb58d68a006 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -31,7 +31,7 @@
 static char             const *input_name = "perf.data";
 static char             *vmlinux = NULL;
 
-static char             default_sort_order[] = "comm,dso";
+static char             default_sort_order[] = "comm,dso,symbol";
 static char             *sort_order = default_sort_order;
 static char             *dso_list_str, *comm_list_str, *sym_list_str,
                         *col_width_list_str;
@@ -99,6 +99,7 @@ struct comm_event {
 struct fork_event {
         struct perf_event_header header;
         u32 pid, ppid;
+        u32 tid, ptid;
 };
 
 struct lost_event {
@@ -252,7 +253,7 @@ static int strcommon(const char *pathname)
 {
         int n = 0;
 
-        while (pathname[n] == cwd[n] && n < cwdlen)
+        while (n < cwdlen && pathname[n] == cwd[n])
                 ++n;
 
         return n;
@@ -1423,7 +1424,7 @@ print_entries:
         if (sort_order == default_sort_order &&
                         parent_pattern == default_parent_pattern) {
                 fprintf(fp, "#\n");
-                fprintf(fp, "# (For more details, try: perf report --sort comm,dso,symbol)\n");
+                fprintf(fp, "# (For a higher level overview, try: perf report --sort comm,dso)\n");
                 fprintf(fp, "#\n");
         }
         fprintf(fp, "\n");
@@ -1608,15 +1609,27 @@ process_comm_event(event_t *event, unsigned long offset, unsigned long head)
 }
 
 static int
-process_fork_event(event_t *event, unsigned long offset, unsigned long head)
+process_task_event(event_t *event, unsigned long offset, unsigned long head)
 {
         struct thread *thread = threads__findnew(event->fork.pid);
         struct thread *parent = threads__findnew(event->fork.ppid);
 
-        dprintf("%p [%p]: PERF_EVENT_FORK: %d:%d\n",
+        dprintf("%p [%p]: PERF_EVENT_%s: (%d:%d):(%d:%d)\n",
                 (void *)(offset + head),
                 (void *)(long)(event->header.size),
-                event->fork.pid, event->fork.ppid);
+                event->header.type == PERF_EVENT_FORK ? "FORK" : "EXIT",
+                event->fork.pid, event->fork.tid,
+                event->fork.ppid, event->fork.ptid);
+
+        /*
+         * A thread clone will have the same PID for both
+         * parent and child.
+         */
+        if (thread == parent)
+                return 0;
+
+        if (event->header.type == PERF_EVENT_EXIT)
+                return 0;
 
         if (!thread || !parent || thread__fork(thread, parent)) {
                 dprintf("problem processing PERF_EVENT_FORK, skipping event.\n");
@@ -1706,7 +1719,8 @@ process_event(event_t *event, unsigned long offset, unsigned long head)
                 return process_comm_event(event, offset, head);
 
         case PERF_EVENT_FORK:
-                return process_fork_event(event, offset, head);
+        case PERF_EVENT_EXIT:
+                return process_task_event(event, offset, head);
 
         case PERF_EVENT_LOST:
                 return process_lost_event(event, offset, head);
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index c0a423004e15..f139f1ab9333 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -285,6 +285,7 @@ static const char *skip_symbols[] = {
         "enter_idle",
         "exit_idle",
         "mwait_idle",
+        "mwait_idle_with_hints",
         "ppc64_runlatch_off",
         "pseries_dedicated_idle_sleep",
         NULL
diff --git a/tools/perf/util/quote.c b/tools/perf/util/quote.c
index c6e5dc0dc82f..2726fe40eb5d 100644
--- a/tools/perf/util/quote.c
+++ b/tools/perf/util/quote.c
@@ -318,7 +318,7 @@ char *quote_path_relative(const char *in, int len,
                 strbuf_addch(out, '"');
         if (prefix) {
                 int off = 0;
-                while (prefix[off] && off < len && prefix[off] == in[off])
+                while (off < len && prefix[off] && prefix[off] == in[off])
                         if (prefix[off] == '/') {
                                 prefix += off + 1;
                                 in += off + 1;
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 28106059bf12..16ddca202948 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -6,7 +6,16 @@
 #include <libelf.h>
 #include <gelf.h>
 #include <elf.h>
+
+#ifndef NO_DEMANGLE
 #include <bfd.h>
+#else
+static inline
+char *bfd_demangle(void __used *v, const char __used *c, int __used i)
+{
+        return NULL;
+}
+#endif
 
 const char *sym_hist_filter;
 
@@ -565,7 +574,7 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
                 goto out_elf_end;
 
         secstrs = elf_getdata(sec_strndx, NULL);
-        if (symstrs == NULL)
+        if (secstrs == NULL)
                 goto out_elf_end;
 
         nr_syms = shdr.sh_size / shdr.sh_entsize;
@@ -652,10 +661,69 @@ out_close:
         return err;
 }
 
+#define BUILD_ID_SIZE 128
+
+static char *dso__read_build_id(struct dso *self, int verbose)
+{
+        int i;
+        GElf_Ehdr ehdr;
+        GElf_Shdr shdr;
+        Elf_Data *build_id_data;
+        Elf_Scn *sec;
+        char *build_id = NULL, *bid;
+        unsigned char *raw;
+        Elf *elf;
+        int fd = open(self->name, O_RDONLY);
+
+        if (fd < 0)
+                goto out;
+
+        elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);
+        if (elf == NULL) {
+                if (verbose)
+                        fprintf(stderr, "%s: cannot read %s ELF file.\n",
+                                __func__, self->name);
+                goto out_close;
+        }
+
+        if (gelf_getehdr(elf, &ehdr) == NULL) {
+                if (verbose)
+                        fprintf(stderr, "%s: cannot get elf header.\n", __func__);
+                goto out_elf_end;
+        }
+
+        sec = elf_section_by_name(elf, &ehdr, &shdr, ".note.gnu.build-id", NULL);
+        if (sec == NULL)
+                goto out_elf_end;
+
+        build_id_data = elf_getdata(sec, NULL);
+        if (build_id_data == NULL)
+                goto out_elf_end;
+        build_id = malloc(BUILD_ID_SIZE);
+        if (build_id == NULL)
+                goto out_elf_end;
+        raw = build_id_data->d_buf + 16;
+        bid = build_id;
+
+        for (i = 0; i < 20; ++i) {
+                sprintf(bid, "%02x", *raw);
+                ++raw;
+                bid += 2;
+        }
+        if (verbose)
+                printf("%s(%s): %s\n", __func__, self->name, build_id);
+out_elf_end:
+        elf_end(elf);
+out_close:
+        close(fd);
+out:
+        return build_id;
+}
+
 int dso__load(struct dso *self, symbol_filter_t filter, int verbose)
 {
-        int size = strlen(self->name) + sizeof("/usr/lib/debug%s.debug");
-        char *name = malloc(size);
+        int size = PATH_MAX;
+        char *name = malloc(size), *build_id = NULL;
         int variant = 0;
         int ret = -1;
         int fd;
@@ -677,7 +745,18 @@ more:
                 case 1: /* Ubuntu */
                         snprintf(name, size, "/usr/lib/debug%s", self->name);
                         break;
-                case 2: /* Sane people */
+                case 2:
+                        build_id = dso__read_build_id(self, verbose);
+                        if (build_id != NULL) {
+                                snprintf(name, size,
+                                         "/usr/lib/debug/.build-id/%.2s/%s.debug",
+                                        build_id, build_id + 2);
+                                free(build_id);
+                                break;
+                        }
+                        variant++;
+                        /* Fall thru */
+                case 3: /* Sane people */
                         snprintf(name, size, "%s", self->name);
                         break;