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In the function lazily compute whether a symbol is an idle function taking into consideration the kernel version and architecture of the machine. As symbols__insert no longer needs to know if a symbol is for the kernel, remove the argument. This change is inspired by mailing list discussion, particularly from Thomas Richter and Heiko Carstens : https://lore.kernel.org/lkml/20260219113850.354271-1-tmricht@linux.ibm.com/ Signed-off-by: Ian Rogers --- tools/perf/builtin-top.c | 6 +- tools/perf/util/symbol-elf.c | 2 +- tools/perf/util/symbol.c | 106 ++++++++++++++++++++++------------- tools/perf/util/symbol.h | 15 +++-- 4 files changed, 85 insertions(+), 44 deletions(-) diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c index 710604c4f6f6..bc3c8e3b6ec0 100644 --- a/tools/perf/builtin-top.c +++ b/tools/perf/builtin-top.c @@ -750,6 +750,7 @@ static void perf_event__process_sample(const struct perf_tool *tool, { struct perf_top *top = container_of(tool, struct perf_top, tool); struct addr_location al; + struct dso *dso = NULL; if (!machine && perf_guest) { static struct intlist *seen; @@ -829,7 +830,10 @@ static void perf_event__process_sample(const struct perf_tool *tool, } } - if (al.sym == NULL || !al.sym->idle) { + if (al.map) + dso = map__dso(al.map); + + if (al.sym == NULL || !symbol__is_idle(al.sym, dso, machine->env)) { struct hists *hists = evsel__hists(evsel); struct hist_entry_iter iter = { .evsel = evsel, diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index 76912c62b6a0..6bb46384aa0c 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -1725,7 +1725,7 @@ dso__load_sym_internal(struct dso *dso, struct map *map, struct symsrc *syms_ss, arch__sym_update(f, &sym); - __symbols__insert(dso__symbols(curr_dso), f, dso__kernel(dso)); + __symbols__insert(dso__symbols(curr_dso), f); nr++; } dso__put(curr_dso); diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index 8662001e1e25..6155f509ca70 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -25,6 +25,8 @@ #include "demangle-ocaml.h" #include "demangle-rust-v0.h" #include "dso.h" +#include "dwarf-regs.h" +#include "env.h" #include "util.h" // lsdir() #include "debug.h" #include "event.h" @@ -51,7 +53,6 @@ static int dso__load_kernel_sym(struct dso *dso, struct map *map); static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map); -static bool symbol__is_idle(const char *name); int vmlinux_path__nr_entries; char **vmlinux_path; @@ -357,8 +358,7 @@ void symbols__delete(struct rb_root_cached *symbols) } } -void __symbols__insert(struct rb_root_cached *symbols, - struct symbol *sym, bool kernel) +void __symbols__insert(struct rb_root_cached *symbols, struct symbol *sym) { struct rb_node **p = &symbols->rb_root.rb_node; struct rb_node *parent = NULL; @@ -366,17 +366,6 @@ void __symbols__insert(struct rb_root_cached *symbols, struct symbol *s; bool leftmost = true; - if (kernel) { - const char *name = sym->name; - /* - * ppc64 uses function descriptors and appends a '.' to the - * start of every instruction address. Remove it. - */ - if (name[0] == '.') - name++; - sym->idle = symbol__is_idle(name); - } - while (*p != NULL) { parent = *p; s = rb_entry(parent, struct symbol, rb_node); @@ -393,7 +382,7 @@ void __symbols__insert(struct rb_root_cached *symbols, void symbols__insert(struct rb_root_cached *symbols, struct symbol *sym) { - __symbols__insert(symbols, sym, false); + __symbols__insert(symbols, sym); } static struct symbol *symbols__find(struct rb_root_cached *symbols, u64 ip) @@ -554,7 +543,7 @@ void dso__reset_find_symbol_cache(struct dso *dso) void dso__insert_symbol(struct dso *dso, struct symbol *sym) { - __symbols__insert(dso__symbols(dso), sym, dso__kernel(dso)); + __symbols__insert(dso__symbols(dso), sym); /* update the symbol cache if necessary */ if (dso__last_find_result_addr(dso) >= sym->start && @@ -716,47 +705,88 @@ int modules__parse(const char *filename, void *arg, return err; } +static int sym_name_cmp(const void *a, const void *b) +{ + const char *name = a; + const char *const *sym = b; + + return strcmp(name, *sym); +} + /* * These are symbols in the kernel image, so make sure that * sym is from a kernel DSO. */ -static bool symbol__is_idle(const char *name) +bool symbol__is_idle(struct symbol *sym, const struct dso *dso, const struct perf_env *env) { - const char * const idle_symbols[] = { + static const char * const idle_symbols[] = { "acpi_idle_do_entry", "acpi_processor_ffh_cstate_enter", "arch_cpu_idle", "cpu_idle", "cpu_startup_entry", - "idle_cpu", - "intel_idle", - "intel_idle_ibrs", "default_idle", - "native_safe_halt", "enter_idle", "exit_idle", - "mwait_idle", - "mwait_idle_with_hints", - "mwait_idle_with_hints.constprop.0", + "idle_cpu", + "native_safe_halt", "poll_idle", - "ppc64_runlatch_off", "pseries_dedicated_idle_sleep", - "psw_idle", - "psw_idle_exit", - NULL }; - int i; - static struct strlist *idle_symbols_list; + const char *name = sym->name; + uint16_t e_machine = env ? env->e_machine : EM_HOST; + + if (sym->idle) + return sym->idle == SYMBOL_IDLE__IDLE; + + if (!dso || dso__kernel(dso) == DSO_SPACE__USER) { + sym->idle = SYMBOL_IDLE__NOT_IDLE; + return false; + } - if (idle_symbols_list) - return strlist__has_entry(idle_symbols_list, name); + /* + * ppc64 uses function descriptors and appends a '.' to the + * start of every instruction address. Remove it. + */ + if (name[0] == '.') + name++; + + + if (bsearch(name, idle_symbols, ARRAY_SIZE(idle_symbols), + sizeof(idle_symbols[0]), sym_name_cmp)) { + sym->idle = SYMBOL_IDLE__IDLE; + return true; + } + + if (e_machine == EM_386 || e_machine == EM_X86_64) { + if (strstarts(name, "mwait_idle") || + strstarts(name, "intel_idle")) { + sym->idle = SYMBOL_IDLE__IDLE; + return true; + } + } + + if (e_machine == EM_PPC64 &&!strcmp(name, "ppc64_runlatch_off")) { + sym->idle = SYMBOL_IDLE__IDLE; + return true; + } - idle_symbols_list = strlist__new(NULL, NULL); + if (e_machine == EM_S390) { + int major = 0, minor = 0; + const char *release = env && env->os_release + ? env->os_release : perf_version_string; - for (i = 0; idle_symbols[i]; i++) - strlist__add(idle_symbols_list, idle_symbols[i]); + sscanf(release, "%d.%d", &major, &minor); - return strlist__has_entry(idle_symbols_list, name); + /* Before v6.10, s390 used psw_idle. */ + if ((major < 6 || (major == 6 && minor < 10)) && strstarts(name, "psw_idle")) { + sym->idle = SYMBOL_IDLE__IDLE; + return true; + } + } + + sym->idle = SYMBOL_IDLE__NOT_IDLE; + return false; } static int map__process_kallsym_symbol(void *arg, const char *name, @@ -785,7 +815,7 @@ static int map__process_kallsym_symbol(void *arg, const char *name, * We will pass the symbols to the filter later, in * map__split_kallsyms, when we have split the maps per module */ - __symbols__insert(root, sym, !strchr(name, '[')); + __symbols__insert(root, sym); return 0; } diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h index 3fb5d146d9b1..508dd9f336e9 100644 --- a/tools/perf/util/symbol.h +++ b/tools/perf/util/symbol.h @@ -24,6 +24,7 @@ struct dso; struct map; struct maps; struct option; +struct perf_env; struct build_id; /* @@ -41,6 +42,12 @@ Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep, GElf_Shdr *shp, const char *name, size_t *idx); #endif +enum symbol_idle_kind { + SYMBOL_IDLE__UNKNOWN = 0, + SYMBOL_IDLE__NOT_IDLE = 1, + SYMBOL_IDLE__IDLE = 2, +}; + /** * A symtab entry. When allocated this may be preceded by an annotation (see * symbol__annotation) and/or a browser_index (see symbol__browser_index). @@ -56,8 +63,8 @@ struct symbol { u8 type:4; /** ELF binding type as defined for st_info. E.g. STB_WEAK or STB_GLOBAL. */ u8 binding:4; - /** Set true for kernel symbols of idle routines. */ - u8 idle:1; + /** Cache for symbol__is_idle. */ + enum symbol_idle_kind idle:2; /** Resolvable but tools ignore it (e.g. idle routines). */ u8 ignore:1; /** Symbol for an inlined function. */ @@ -184,8 +191,7 @@ int dso__synthesize_plt_symbols(struct dso *dso, struct symsrc *ss); char *dso__demangle_sym(struct dso *dso, int kmodule, const char *elf_name); -void __symbols__insert(struct rb_root_cached *symbols, struct symbol *sym, - bool kernel); +void __symbols__insert(struct rb_root_cached *symbols, struct symbol *sym); void symbols__insert(struct rb_root_cached *symbols, struct symbol *sym); void symbols__fixup_duplicate(struct rb_root_cached *symbols); void symbols__fixup_end(struct rb_root_cached *symbols, bool is_kallsyms); @@ -269,5 +275,6 @@ enum { }; int symbol__validate_sym_arguments(void); +bool symbol__is_idle(struct symbol *sym, const struct dso *dso, const struct perf_env *env); #endif /* __PERF_SYMBOL */ -- 2.53.0.473.g4a7958ca14-goog