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authorLinus Torvalds <torvalds@linux-foundation.org>2012-12-11 18:14:31 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2012-12-11 18:14:31 -0800
commit090f8ccba37034cec5a5972a70abeaae7eb0222b (patch)
tree0b7cf8a4bb94601816399acfb336835fbf309a2a /tools/perf/tests/vmlinux-kallsyms.c
parentaefb058b0c27dafb15072406fbfd92d2ac2c8790 (diff)
parentcc1b39dbf9f55a438e8a21a694394c20e6a17129 (diff)
Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar: "Lots of activity: 211 files changed, 8328 insertions(+), 4116 deletions(-) most of it on the tooling side. Main changes: * ftrace enhancements and fixes from Steve Rostedt. * uprobes fixes, cleanups and preparation for the ARM port from Oleg Nesterov. * UAPI fixes, from David Howels - prepares the arch/x86 UAPI transition * Separate perf tests into multiple objects, one per test, from Jiri Olsa. * Make hardware event translations available in sysfs, from Jiri Olsa. * Fixes to /proc/pid/maps parsing, preparatory to supporting data maps, from Namhyung Kim * Implement ui_progress for GTK, from Namhyung Kim * Add framework for automated perf_event_attr tests, where tools with different command line options will be run from a 'perf test', via python glue, and the perf syscall will be intercepted to verify that the perf_event_attr fields set by the tool are those expected, from Jiri Olsa * Add a 'link' method for hists, so that we can have the leader with buckets for all the entries in all the hists. This new method is now used in the default 'diff' output, making the sum of the 'baseline' column be 100%, eliminating blind spots. * libtraceevent fixes for compiler warnings trying to make perf it build on some distros, like fedora 14, 32-bit, some of the warnings really pointed to real bugs. * Add a browser for 'perf script' and make it available from the report and annotate browsers. It does filtering to find the scripts that handle events found in the perf.data file used. From Feng Tang * perf inject changes to allow showing where a task sleeps, from Andrew Vagin. * Makefile improvements from Namhyung Kim. * Add --pre and --post command hooks in 'stat', from Peter Zijlstra. * Don't stop synthesizing threads when one vanishes, this is for the existing threads when we start a tool like trace. * Use sched:sched_stat_runtime to provide a thread summary, this produces the same output as the 'trace summary' subcommand of tglx's original "trace" tool. * Support interrupted syscalls in 'trace' * Add an event duration column and filter in 'trace'. * There are references to the man pages in some tools, so try to build Documentation when installing, warning the user if that is not possible, from Borislav Petkov. * Give user better message if precise is not supported, from David Ahern. * Try to find cross-built objdump path by using the session environment information in the perf.data file header, from Irina Tirdea, original patch and idea by Namhyung Kim. * Diplays more output on features check for make V=1, so that one can figure out what is happening by looking at gcc output, etc. From Jiri Olsa. * Add on_exit implementation for systems without one, e.g. Android, from Bernhard Rosenkraenzer. * Only process events for vcpus of interest, helps handling large number of events, from David Ahern. * Cross compilation fixes for Android, from Irina Tirdea. * Add documentation on compiling for Android, from Irina Tirdea. * perf diff improvements from Jiri Olsa. * Target (task/user/cpu/syswide) handling improvements, from Namhyung Kim. * Add support in 'trace' for tracing workload given by command line, from Namhyung Kim. * ... and much more." * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (194 commits) uprobes: Use percpu_rw_semaphore to fix register/unregister vs dup_mmap() race perf evsel: Introduce is_group_member method perf powerpc: Use uapi/unistd.h to fix build error tools: Pass the target in descend tools: Honour the O= flag when tool build called from a higher Makefile tools: Define a Makefile function to do subdir processing perf ui: Always compile browser setup code perf ui: Add ui_progress__finish() perf ui gtk: Implement ui_progress functions perf ui: Introduce generic ui_progress helper perf ui tui: Move progress.c under ui/tui directory perf tools: Add basic event modifier sanity check perf tools: Omit group members from perf_evlist__disable/enable perf tools: Ensure single disable call per event in record comand perf tools: Fix 'disabled' attribute config for record command perf tools: Fix attributes for '{}' defined event groups perf tools: Use sscanf for parsing /proc/pid/maps perf tools: Add gtk.<command> config option for launching GTK browser perf tools: Fix compile error on NO_NEWT=1 build perf hists: Initialize all of he->stat with zeroes ...
Diffstat (limited to 'tools/perf/tests/vmlinux-kallsyms.c')
-rw-r--r--tools/perf/tests/vmlinux-kallsyms.c230
1 files changed, 230 insertions, 0 deletions
diff --git a/tools/perf/tests/vmlinux-kallsyms.c b/tools/perf/tests/vmlinux-kallsyms.c
new file mode 100644
index 000000000000..0d1cdbee2f59
--- /dev/null
+++ b/tools/perf/tests/vmlinux-kallsyms.c
@@ -0,0 +1,230 @@
+#include <linux/compiler.h>
+#include <linux/rbtree.h>
+#include <string.h>
+#include "map.h"
+#include "symbol.h"
+#include "util.h"
+#include "tests.h"
+#include "debug.h"
+#include "machine.h"
+
+static int vmlinux_matches_kallsyms_filter(struct map *map __maybe_unused,
+ struct symbol *sym)
+{
+ bool *visited = symbol__priv(sym);
+ *visited = true;
+ return 0;
+}
+
+int test__vmlinux_matches_kallsyms(void)
+{
+ int err = -1;
+ struct rb_node *nd;
+ struct symbol *sym;
+ struct map *kallsyms_map, *vmlinux_map;
+ struct machine kallsyms, vmlinux;
+ enum map_type type = MAP__FUNCTION;
+ struct ref_reloc_sym ref_reloc_sym = { .name = "_stext", };
+
+ /*
+ * Step 1:
+ *
+ * Init the machines that will hold kernel, modules obtained from
+ * both vmlinux + .ko files and from /proc/kallsyms split by modules.
+ */
+ machine__init(&kallsyms, "", HOST_KERNEL_ID);
+ machine__init(&vmlinux, "", HOST_KERNEL_ID);
+
+ /*
+ * Step 2:
+ *
+ * Create the kernel maps for kallsyms and the DSO where we will then
+ * load /proc/kallsyms. Also create the modules maps from /proc/modules
+ * and find the .ko files that match them in /lib/modules/`uname -r`/.
+ */
+ if (machine__create_kernel_maps(&kallsyms) < 0) {
+ pr_debug("machine__create_kernel_maps ");
+ return -1;
+ }
+
+ /*
+ * Step 3:
+ *
+ * Load and split /proc/kallsyms into multiple maps, one per module.
+ */
+ if (machine__load_kallsyms(&kallsyms, "/proc/kallsyms", type, NULL) <= 0) {
+ pr_debug("dso__load_kallsyms ");
+ goto out;
+ }
+
+ /*
+ * Step 4:
+ *
+ * kallsyms will be internally on demand sorted by name so that we can
+ * find the reference relocation * symbol, i.e. the symbol we will use
+ * to see if the running kernel was relocated by checking if it has the
+ * same value in the vmlinux file we load.
+ */
+ kallsyms_map = machine__kernel_map(&kallsyms, type);
+
+ sym = map__find_symbol_by_name(kallsyms_map, ref_reloc_sym.name, NULL);
+ if (sym == NULL) {
+ pr_debug("dso__find_symbol_by_name ");
+ goto out;
+ }
+
+ ref_reloc_sym.addr = sym->start;
+
+ /*
+ * Step 5:
+ *
+ * Now repeat step 2, this time for the vmlinux file we'll auto-locate.
+ */
+ if (machine__create_kernel_maps(&vmlinux) < 0) {
+ pr_debug("machine__create_kernel_maps ");
+ goto out;
+ }
+
+ vmlinux_map = machine__kernel_map(&vmlinux, type);
+ map__kmap(vmlinux_map)->ref_reloc_sym = &ref_reloc_sym;
+
+ /*
+ * Step 6:
+ *
+ * Locate a vmlinux file in the vmlinux path that has a buildid that
+ * matches the one of the running kernel.
+ *
+ * While doing that look if we find the ref reloc symbol, if we find it
+ * we'll have its ref_reloc_symbol.unrelocated_addr and then
+ * maps__reloc_vmlinux will notice and set proper ->[un]map_ip routines
+ * to fixup the symbols.
+ */
+ if (machine__load_vmlinux_path(&vmlinux, type,
+ vmlinux_matches_kallsyms_filter) <= 0) {
+ pr_debug("machine__load_vmlinux_path ");
+ goto out;
+ }
+
+ err = 0;
+ /*
+ * Step 7:
+ *
+ * Now look at the symbols in the vmlinux DSO and check if we find all of them
+ * in the kallsyms dso. For the ones that are in both, check its names and
+ * end addresses too.
+ */
+ for (nd = rb_first(&vmlinux_map->dso->symbols[type]); nd; nd = rb_next(nd)) {
+ struct symbol *pair, *first_pair;
+ bool backwards = true;
+
+ sym = rb_entry(nd, struct symbol, rb_node);
+
+ if (sym->start == sym->end)
+ continue;
+
+ first_pair = machine__find_kernel_symbol(&kallsyms, type, sym->start, NULL, NULL);
+ pair = first_pair;
+
+ if (pair && pair->start == sym->start) {
+next_pair:
+ if (strcmp(sym->name, pair->name) == 0) {
+ /*
+ * kallsyms don't have the symbol end, so we
+ * set that by using the next symbol start - 1,
+ * in some cases we get this up to a page
+ * wrong, trace_kmalloc when I was developing
+ * this code was one such example, 2106 bytes
+ * off the real size. More than that and we
+ * _really_ have a problem.
+ */
+ s64 skew = sym->end - pair->end;
+ if (llabs(skew) < page_size)
+ continue;
+
+ pr_debug("%#" PRIx64 ": diff end addr for %s v: %#" PRIx64 " k: %#" PRIx64 "\n",
+ sym->start, sym->name, sym->end, pair->end);
+ } else {
+ struct rb_node *nnd;
+detour:
+ nnd = backwards ? rb_prev(&pair->rb_node) :
+ rb_next(&pair->rb_node);
+ if (nnd) {
+ struct symbol *next = rb_entry(nnd, struct symbol, rb_node);
+
+ if (next->start == sym->start) {
+ pair = next;
+ goto next_pair;
+ }
+ }
+
+ if (backwards) {
+ backwards = false;
+ pair = first_pair;
+ goto detour;
+ }
+
+ pr_debug("%#" PRIx64 ": diff name v: %s k: %s\n",
+ sym->start, sym->name, pair->name);
+ }
+ } else
+ pr_debug("%#" PRIx64 ": %s not on kallsyms\n", sym->start, sym->name);
+
+ err = -1;
+ }
+
+ if (!verbose)
+ goto out;
+
+ pr_info("Maps only in vmlinux:\n");
+
+ for (nd = rb_first(&vmlinux.kmaps.maps[type]); nd; nd = rb_next(nd)) {
+ struct map *pos = rb_entry(nd, struct map, rb_node), *pair;
+ /*
+ * If it is the kernel, kallsyms is always "[kernel.kallsyms]", while
+ * the kernel will have the path for the vmlinux file being used,
+ * so use the short name, less descriptive but the same ("[kernel]" in
+ * both cases.
+ */
+ pair = map_groups__find_by_name(&kallsyms.kmaps, type,
+ (pos->dso->kernel ?
+ pos->dso->short_name :
+ pos->dso->name));
+ if (pair)
+ pair->priv = 1;
+ else
+ map__fprintf(pos, stderr);
+ }
+
+ pr_info("Maps in vmlinux with a different name in kallsyms:\n");
+
+ for (nd = rb_first(&vmlinux.kmaps.maps[type]); nd; nd = rb_next(nd)) {
+ struct map *pos = rb_entry(nd, struct map, rb_node), *pair;
+
+ pair = map_groups__find(&kallsyms.kmaps, type, pos->start);
+ if (pair == NULL || pair->priv)
+ continue;
+
+ if (pair->start == pos->start) {
+ pair->priv = 1;
+ pr_info(" %" PRIx64 "-%" PRIx64 " %" PRIx64 " %s in kallsyms as",
+ pos->start, pos->end, pos->pgoff, pos->dso->name);
+ if (pos->pgoff != pair->pgoff || pos->end != pair->end)
+ pr_info(": \n*%" PRIx64 "-%" PRIx64 " %" PRIx64 "",
+ pair->start, pair->end, pair->pgoff);
+ pr_info(" %s\n", pair->dso->name);
+ pair->priv = 1;
+ }
+ }
+
+ pr_info("Maps only in kallsyms:\n");
+
+ for (nd = rb_first(&kallsyms.kmaps.maps[type]);
+ nd; nd = rb_next(nd)) {
+ struct map *pos = rb_entry(nd, struct map, rb_node);
+
+ if (!pos->priv)
+ map__fprintf(pos, stderr);
+ }
+out:
+ return err;
+}