From nobody Fri Apr 3 01:23:06 2026 Received: from mail-dy1-f202.google.com (mail-dy1-f202.google.com [74.125.82.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0AD1B3E715B for ; Wed, 25 Mar 2026 16:18:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774455529; cv=none; b=tDNQURhNzAhFW/sEAddm2wfvUUKVbzjlFUnAcnkhTjt28KSvp97FgFBE2w9D9bl8ZFOq6wOtE5j4INuKSd9tdwvfqk8iqUcN5SZaiUH9L79O3XRJ1cASREodaAh0o+O+lONQvjGyTPbwxycoa5vvqulAU7Ax/xOn2jvRzuyeCSA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774455529; c=relaxed/simple; bh=ujXVSPWi9K19hqWKNR2YVC6FSEsshyigdTUKmE+YX+c=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=bDbBODwAxJbcr2td/GQmupM1UqYrUDKos3WVLCFpCMsvUH8sY/adIO0eeff7mKriB5r0TBFIWKiN8T+G5r8urBREBwu0MujrnImc1fMzL/kkZ9hiCQADNmkI9G5rjCc+rretYR/Xn9vpDY9sc6tGVaYMB5bhfZFC+avOVf79vq4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--irogers.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=IKntJImp; arc=none smtp.client-ip=74.125.82.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--irogers.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="IKntJImp" Received: by mail-dy1-f202.google.com with SMTP id 5a478bee46e88-2c0ffce2570so201566eec.1 for ; Wed, 25 Mar 2026 09:18:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1774455527; x=1775060327; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=c2lap/UJ8BFoo4cOMxZbeksxuRKLVHxwjfRDIyMOFwc=; b=IKntJImp2XZ6KFYQeqYjWHhweUdbDrizLLKTDjbichTFN2ba6o4ZCTwyz5AUTSPn47 Iyyja0oqbC/fMlkDdCMgUpNFDcoXWI9BpIKFut1v/buTcIXTADOZ1FiRzfO+LfxUnFR/ SWKzZRJTn0ID2ATDi5mSXyBBtsV0Cv9+TvFnuMACoByJnP9bG+zkT4b9blMA9Ru9jQoF A8o9IgnXizvlJplwVoA5sajdcOPlegpoIYBZlPzG7lKaHBnpR0JvTFCp6vWSHIycugf5 OpbxiclCxZDQOayoprjU8Hbr8RYPjt4ieGhDPdPJmTjGeOGiTUHrZHXBXbhb/ixxnYjA H7FQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1774455527; x=1775060327; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=c2lap/UJ8BFoo4cOMxZbeksxuRKLVHxwjfRDIyMOFwc=; b=pAsoO4S+414GEAZ/6hom1eT7etvsKuVCTTujpo1ZW3oEwDDR+GgNhunPT93/GtCvSi fhfcgS2sL4NMn36zLvgROyxyVb2vYI7Q/SVvRbeJp45CeT120BNPI0voGz6ebD+2p1BY W37Ekos4zQCdhgbREEFTiRiOIQIHaV5CxEe2V54pdEhKrbHd7Eg4WFvejrmRGo3TSaSv 4YkL+vAfh5Eo2XCSGcxZBUCI7XlxZmTxaRzv4Fe+JjLhGnIRleJMj1/v8xF627tPO7XX rFlMcS9U68rHVrlwBAuyTDDVT16/E8l5PTD2SWeGCnTKSZ5ocBaw/vWLhbVWqsdl1w+k 8maA== X-Forwarded-Encrypted: i=1; AJvYcCUgO5E85R+8ANBWbEdt0pPaubRVz+zaWPuiuzqyVX1snFDbHtu0pvdCRKHLXbL1VO/i1w7vH/CpMJj1iuM=@vger.kernel.org X-Gm-Message-State: AOJu0YykeaPXtKBVPAYrQIsUIyeb83R07u8h1XV5HG+K1tQGaK0mxa5c AliD4DQjT5X2BL6Rlzulf521zwU+cdJyui43FNycF+eTRCueznk3ijRSHTomakkTD6I/QZIj863 3OYn28hEaGw== X-Received: from dyw28.prod.google.com ([2002:a05:7300:881c:b0:2be:4118:56f1]) (user=irogers job=prod-delivery.src-stubby-dispatcher) by 2002:a05:7300:7304:b0:2c0:c96a:a4db with SMTP id 5a478bee46e88-2c15d2ba52bmr2456264eec.4.1774455526788; Wed, 25 Mar 2026 09:18:46 -0700 (PDT) Date: Wed, 25 Mar 2026 09:18:36 -0700 In-Reply-To: <20260302234343.564937-1-irogers@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260302234343.564937-1-irogers@google.com> X-Mailer: git-send-email 2.53.0.1018.g2bb0e51243-goog Message-ID: <20260325161836.1029457-1-irogers@google.com> Subject: [PATCH v2] perf symbol: Lazily compute idle and use the perf_env From: Ian Rogers To: acme@kernel.org, namhyung@kernel.org, tmricht@linux.ibm.com Cc: irogers@google.com, agordeev@linux.ibm.com, gor@linux.ibm.com, hca@linux.ibm.com, japo@linux.ibm.com, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-s390@vger.kernel.org, sumanthk@linux.ibm.com, jameshongleiwang@126.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Move the idle boolean to a helper symbol__is_idle function. 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/ The change switches x86 matches to use strstarts which means intel_idle_irq is matched as part of strstarts(name, "intel_idle"), a change suggested by Honglei Wang in: https://lore.kernel.org/lkml/20260323085255.98173-1-jameshongleiwang@126.co= m/ Signed-off-by: Ian Rogers --- v1: https://lore.kernel.org/lkml/20260302234343.564937-1-irogers@google.com/ --- tools/perf/builtin-top.c | 6 +- tools/perf/util/symbol-elf.c | 2 +- tools/perf/util/symbol.c | 105 ++++++++++++++++++++++------------- tools/perf/util/symbol.h | 15 +++-- 4 files changed, 84 insertions(+), 44 deletions(-) diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c index 37950efb28ac..bdc1c761cd61 100644 --- a/tools/perf/builtin-top.c +++ b/tools/perf/builtin-top.c @@ -751,6 +751,7 @@ static void perf_event__process_sample(const struct per= f_tool *tool, { struct perf_top *top =3D container_of(tool, struct perf_top, tool); struct addr_location al; + struct dso *dso =3D NULL; =20 if (!machine && perf_guest) { static struct intlist *seen; @@ -830,7 +831,10 @@ static void perf_event__process_sample(const struct pe= rf_tool *tool, } } =20 - if (al.sym =3D=3D NULL || !al.sym->idle) { + if (al.map) + dso =3D map__dso(al.map); + + if (al.sym =3D=3D NULL || !symbol__is_idle(al.sym, dso, machine->env)) { struct hists *hists =3D evsel__hists(evsel); struct hist_entry_iter iter =3D { .evsel =3D evsel, diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index 3cd4e5a03cc5..9fabf5146d89 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -1723,7 +1723,7 @@ dso__load_sym_internal(struct dso *dso, struct map *m= ap, struct symsrc *syms_ss, =20 arch__sym_update(f, &sym); =20 - __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 ce9195717f44..1a357af93a0a 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 "event.h" #include "machine.h" @@ -50,7 +52,6 @@ =20 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); =20 int vmlinux_path__nr_entries; char **vmlinux_path; @@ -357,8 +358,7 @@ void symbols__delete(struct rb_root_cached *symbols) } } =20 -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 =3D &symbols->rb_root.rb_node; struct rb_node *parent =3D NULL; @@ -366,17 +366,6 @@ void __symbols__insert(struct rb_root_cached *symbols, struct symbol *s; bool leftmost =3D true; =20 - if (kernel) { - const char *name =3D sym->name; - /* - * ppc64 uses function descriptors and appends a '.' to the - * start of every instruction address. Remove it. - */ - if (name[0] =3D=3D '.') - name++; - sym->idle =3D symbol__is_idle(name); - } - while (*p !=3D NULL) { parent =3D *p; s =3D rb_entry(parent, struct symbol, rb_node); @@ -393,7 +382,7 @@ void __symbols__insert(struct rb_root_cached *symbols, =20 void symbols__insert(struct rb_root_cached *symbols, struct symbol *sym) { - __symbols__insert(symbols, sym, false); + __symbols__insert(symbols, sym); } =20 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) =20 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); =20 /* update the symbol cache if necessary */ if (dso__last_find_result_addr(dso) >=3D sym->start && @@ -716,47 +705,87 @@ int modules__parse(const char *filename, void *arg, return err; } =20 +static int sym_name_cmp(const void *a, const void *b) +{ + const char *name =3D a; + const char *const *sym =3D 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 stru= ct perf_env *env) { - const char * const idle_symbols[] =3D { + static const char * const idle_symbols[] =3D { "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 =3D sym->name; + uint16_t e_machine =3D env ? env->e_machine : EM_HOST; =20 - if (idle_symbols_list) - return strlist__has_entry(idle_symbols_list, name); + if (sym->idle) + return sym->idle =3D=3D SYMBOL_IDLE__IDLE; =20 - idle_symbols_list =3D strlist__new(NULL, NULL); + if (!dso || dso__kernel(dso) =3D=3D DSO_SPACE__USER) { + sym->idle =3D SYMBOL_IDLE__NOT_IDLE; + return false; + } =20 - for (i =3D 0; idle_symbols[i]; i++) - strlist__add(idle_symbols_list, idle_symbols[i]); + /* + * ppc64 uses function descriptors and appends a '.' to the + * start of every instruction address. Remove it. + */ + if (name[0] =3D=3D '.') + name++; =20 - return strlist__has_entry(idle_symbols_list, name); + if (bsearch(name, idle_symbols, ARRAY_SIZE(idle_symbols), + sizeof(idle_symbols[0]), sym_name_cmp)) { + sym->idle =3D SYMBOL_IDLE__IDLE; + return true; + } + + if (e_machine =3D=3D EM_386 || e_machine =3D=3D EM_X86_64) { + if (strstarts(name, "mwait_idle") || + strstarts(name, "intel_idle")) { + sym->idle =3D SYMBOL_IDLE__IDLE; + return true; + } + } + + if (e_machine =3D=3D EM_PPC64 && !strcmp(name, "ppc64_runlatch_off")) { + sym->idle =3D SYMBOL_IDLE__IDLE; + return true; + } + + if (e_machine =3D=3D EM_S390) { + int major =3D 0, minor =3D 0; + const char *release =3D env && env->os_release + ? env->os_release : perf_version_string; + + sscanf(release, "%d.%d", &major, &minor); + + /* Before v6.10, s390 used psw_idle. */ + if ((major < 6 || (major =3D=3D 6 && minor < 10)) && strstarts(name, "ps= w_idle")) { + sym->idle =3D SYMBOL_IDLE__IDLE; + return true; + } + } + + sym->idle =3D SYMBOL_IDLE__NOT_IDLE; + return false; } =20 static int map__process_kallsym_symbol(void *arg, const char *name, @@ -785,7 +814,7 @@ 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); =20 return 0; } diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h index c67814d6d6d6..f26f67bd7982 100644 --- a/tools/perf/util/symbol.h +++ b/tools/perf/util/symbol.h @@ -25,6 +25,7 @@ struct dso; struct map; struct maps; struct option; +struct perf_env; struct build_id; =20 /* @@ -42,6 +43,12 @@ Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep, GElf_Shdr *shp, const char *name, size_t *idx); #endif =20 +enum symbol_idle_kind { + SYMBOL_IDLE__UNKNOWN =3D 0, + SYMBOL_IDLE__NOT_IDLE =3D 1, + SYMBOL_IDLE__IDLE =3D 2, +}; + /** * A symtab entry. When allocated this may be preceded by an annotation (s= ee * symbol__annotation) and/or a browser_index (see symbol__browser_index). @@ -57,8 +64,8 @@ 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. */ @@ -202,8 +209,7 @@ int dso__synthesize_plt_symbols(struct dso *dso, struct= symsrc *ss); =20 char *dso__demangle_sym(struct dso *dso, int kmodule, const char *elf_name= ); =20 -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); @@ -286,5 +292,6 @@ enum { }; =20 int symbol__validate_sym_arguments(void); +bool symbol__is_idle(struct symbol *sym, const struct dso *dso, const stru= ct perf_env *env); =20 #endif /* __PERF_SYMBOL */ --=20 2.53.0.1018.g2bb0e51243-goog