From nobody Mon Feb 9 06:25:49 2026 Received: from mail-yb1-f201.google.com (mail-yb1-f201.google.com [209.85.219.201]) (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 805871F585F for ; Tue, 4 Mar 2025 05:04:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.219.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741064680; cv=none; b=HCMj6u7gBuidNTXxM9tKXjguK2rawJUYPAaV0JN6s4NITVPkJ1jC7wsLrNXhR8sKhBS7NLYrqPLrXe8zMlsOHWdGVl7Qlc8ivf4l+oTeUoFSgDNW4SifRaEjco9nuMXG7uR6xfQIl2eNFGV2lMq8g7lkiEqqYluWg9jApIexaC4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741064680; c=relaxed/simple; bh=8W6V3Mdc3xWK0YKc3vJr7nrKXuZoyFr+hOU5CbP9q3I=; h=Date:In-Reply-To:Message-Id:Mime-Version:References:Subject:From: To:Content-Type; b=Rmo3MUhd6V6j7w8ICVz/G/yM3BUen79RRXBd+ZO084n4xpwkEouERYi/YaKB0Rytcou2KAk5L+Vu8di7CJW2ebwhOQQ+QuXm5PbSjzaa9MskCEbTBfuQRDSaahQalDURLaYTAzwLs3cuw1RitcqzBohJSqTY6qkh5hD6/JEeyZw= 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=rvB+abLG; arc=none smtp.client-ip=209.85.219.201 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="rvB+abLG" Received: by mail-yb1-f201.google.com with SMTP id 3f1490d57ef6-e583e274095so6256875276.3 for ; Mon, 03 Mar 2025 21:04:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1741064677; x=1741669477; darn=vger.kernel.org; h=to:from:subject:references:mime-version:message-id:in-reply-to:date :from:to:cc:subject:date:message-id:reply-to; bh=0epwbCKMSYykA4kwC9635o/Y9dNp67Qk+FkRsi9vRck=; b=rvB+abLGg6jZtYqZ8BJodQuMki4522/sWQ+d11uoQ12HBAL5qc3u427ygw6JQ9EB4z JMclgs4UexldIDfplkViUV0l0e+h4uHGHZGZh68OzYgTzczD55jC0VKaQ4LC5mI5W7VI ns7I7IWzwkDONnPEXFqTB5MzvLAIqFyI8J7KtMpojWAkwctjlBvBUFUKFKXIyGmoNG/U ruxtQOv7EUhajAuvh/GZ5befVYDfxt2oLL7HRwrAgdTNvEWJgjHdvpcrsrovbLVMSWaj HGngiJ7Dp/RNTtxjR0QkbR1KfVA+dxuJc61gjUhbKHUUkQ79CiBS++Gy1Z3Fi3Yluo0H lO1g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1741064677; x=1741669477; h=to:from:subject:references:mime-version:message-id:in-reply-to:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=0epwbCKMSYykA4kwC9635o/Y9dNp67Qk+FkRsi9vRck=; b=SBncMJ1fD4ttDA1nQfe20qlcLwOvONkioJhfLfYb3D2stuhDYoqkpTutYsMVCEGDuF EA1qQbH21A+2gHoQxbYSH2KYemqUdqhNwYJCNnkyR9dSP+mgJ3zJB8abUVgQCdqKSesz NVkpgCWVDGBYixa18acKXfJFXbnDo5eqTWB6q5inCRhL+A/swy/nqK5KhdgiMC7krGz1 zlGh2S6Wcq8subDt6iH15/8loCF/TcxknJhj2T38V27SzPD3dCSCVCxsHmIsIzAeGOKE ioCL7nPHhDDA8vBdvob26jpv+0uAzdcfjjj1f5CepzJRhEjVRj/jEwNuQE6A3vHYJwUa momw== X-Forwarded-Encrypted: i=1; AJvYcCWaUPMKrjzoUMhKn98IqoxijnG6+pjxg4xMfuuloXayljN966OEKXXi1FzMDtOV7gZVevDkDOfwGOrtYao=@vger.kernel.org X-Gm-Message-State: AOJu0YzATLnxR4sOOoIPU/JrNq7KGiN/hpEZLX/MNe1p512kMEQrvJgL 18j1Ko+dn3kTCV2fCepF0ae7vgrBy6YHiA7806Mxc6N1HBqVJ503jj9ouw3GLzxPpdyIP/jyF4F ylflplw== X-Google-Smtp-Source: AGHT+IGQOEYy9F+mKAlJH/5NtOSqhO82ZI1AvFTLT8lzKUM5pGf0NQmOzgTD0cSkWhSSO9Guw5PeqZ3WE930 X-Received: from irogers.svl.corp.google.com ([2620:15c:2c5:11:8af9:d1f7:bca9:da2]) (user=irogers job=sendgmr) by 2002:a5b:b43:0:b0:e5e:fdc:88e1 with SMTP id 3f1490d57ef6-e60b2f347b6mr1983728276.4.1741064677594; Mon, 03 Mar 2025 21:04:37 -0800 (PST) Date: Mon, 3 Mar 2025 21:03:01 -0800 In-Reply-To: <20250304050305.901167-1-irogers@google.com> Message-Id: <20250304050305.901167-8-irogers@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250304050305.901167-1-irogers@google.com> X-Mailer: git-send-email 2.48.1.711.g2feabab25a-goog Subject: [PATCH v4 07/11] perf thread: Add support for reading the e_machine type for a thread From: Ian Rogers To: Ian Rogers , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Adrian Hunter , Kan Liang , John Garry , Will Deacon , James Clark , Mike Leach , Leo Yan , guoren , Paul Walmsley , Palmer Dabbelt , Albert Ou , Charlie Jenkins , Bibo Mao , Huacai Chen , Catalin Marinas , Jiri Slaby , "=?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?=" , Howard Chu , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-arm-kernel@lists.infradead.org, "linux-csky@vger.kernel.org" , linux-riscv@lists.infradead.org, Arnd Bergmann Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" First try to read the e_machine from the dsos associated with the thread's maps. If live use the executable from /proc/pid/exe and read the e_machine from the ELF header. On failure use EM_HOST. Change builtin-trace syscall functions to pass e_machine from the thread rather than EM_HOST, so that in later patches when syscalltbl can use the e_machine the system calls are specific to the architecture. Signed-off-by: Ian Rogers --- tools/perf/builtin-trace.c | 43 ++++++++++---------- tools/perf/util/thread.c | 80 ++++++++++++++++++++++++++++++++++++++ tools/perf/util/thread.h | 14 ++++++- 3 files changed, 115 insertions(+), 22 deletions(-) diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index cfc8cb8cbef8..49199d753b7c 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -2729,16 +2729,16 @@ static int trace__sys_enter(struct trace *trace, st= ruct evsel *evsel, int printed =3D 0; struct thread *thread; int id =3D perf_evsel__sc_tp_uint(evsel, id, sample), err =3D -1; - int augmented_args_size =3D 0; + int augmented_args_size =3D 0, e_machine; void *augmented_args =3D NULL; - /* TODO: get e_machine from thread. */ - struct syscall *sc =3D trace__syscall_info(trace, evsel, EM_HOST, id); + struct syscall *sc; struct thread_trace *ttrace; =20 - if (sc =3D=3D NULL) - return -1; - thread =3D machine__findnew_thread(trace->host, sample->pid, sample->tid); + e_machine =3D thread__e_machine(thread, trace->host); + sc =3D trace__syscall_info(trace, evsel, e_machine, id); + if (sc =3D=3D NULL) + goto out_put; ttrace =3D thread__trace(thread, trace); if (ttrace =3D=3D NULL) goto out_put; @@ -2806,17 +2806,18 @@ static int trace__fprintf_sys_enter(struct trace *t= race, struct evsel *evsel, struct thread_trace *ttrace; struct thread *thread; int id =3D perf_evsel__sc_tp_uint(evsel, id, sample), err =3D -1; - /* TODO: get e_machine from thread. */ - struct syscall *sc =3D trace__syscall_info(trace, evsel, EM_HOST, id); + struct syscall *sc; char msg[1024]; void *args, *augmented_args =3D NULL; - int augmented_args_size; + int augmented_args_size, e_machine; size_t printed =3D 0; =20 - if (sc =3D=3D NULL) - return -1; =20 thread =3D machine__findnew_thread(trace->host, sample->pid, sample->tid); + e_machine =3D thread__e_machine(thread, trace->host); + sc =3D trace__syscall_info(trace, evsel, e_machine, id); + if (sc =3D=3D NULL) + return -1; ttrace =3D thread__trace(thread, trace); /* * We need to get ttrace just to make sure it is there when syscall__scnp= rintf_args() @@ -2881,15 +2882,15 @@ static int trace__sys_exit(struct trace *trace, str= uct evsel *evsel, bool duration_calculated =3D false; struct thread *thread; int id =3D perf_evsel__sc_tp_uint(evsel, id, sample), err =3D -1, callcha= in_ret =3D 0, printed =3D 0; - int alignment =3D trace->args_alignment; - /* TODO: get e_machine from thread. */ - struct syscall *sc =3D trace__syscall_info(trace, evsel, EM_HOST, id); + int alignment =3D trace->args_alignment, e_machine; + struct syscall *sc; struct thread_trace *ttrace; =20 - if (sc =3D=3D NULL) - return -1; - thread =3D machine__findnew_thread(trace->host, sample->pid, sample->tid); + e_machine =3D thread__e_machine(thread, trace->host); + sc =3D trace__syscall_info(trace, evsel, e_machine, id); + if (sc =3D=3D NULL) + goto out_put; ttrace =3D thread__trace(thread, trace); if (ttrace =3D=3D NULL) goto out_put; @@ -3236,8 +3237,8 @@ static int trace__event_handler(struct trace *trace, = struct evsel *evsel, =20 if (evsel =3D=3D trace->syscalls.events.bpf_output) { int id =3D perf_evsel__sc_tp_uint(evsel, id, sample); - /* TODO: get e_machine from thread. */ - struct syscall *sc =3D trace__syscall_info(trace, evsel, EM_HOST, id); + int e_machine =3D thread ? thread__e_machine(thread, trace->host) : EM_H= OST; + struct syscall *sc =3D trace__syscall_info(trace, evsel, e_machine, id); =20 if (sc) { fprintf(trace->output, "%s(", sc->name); @@ -4881,6 +4882,7 @@ static size_t trace__fprintf_thread(FILE *fp, struct = thread *thread, struct trac { size_t printed =3D 0; struct thread_trace *ttrace =3D thread__priv(thread); + int e_machine =3D thread__e_machine(thread, trace->host); double ratio; =20 if (ttrace =3D=3D NULL) @@ -4900,8 +4902,7 @@ static size_t trace__fprintf_thread(FILE *fp, struct = thread *thread, struct trac else if (fputc('\n', fp) !=3D EOF) ++printed; =20 - /* TODO: get e_machine from thread. */ - printed +=3D thread__dump_stats(ttrace, trace, EM_HOST, fp); + printed +=3D thread__dump_stats(ttrace, trace, e_machine, fp); =20 return printed; } diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c index 0ffdd52d86d7..89585f53c1d5 100644 --- a/tools/perf/util/thread.c +++ b/tools/perf/util/thread.c @@ -1,5 +1,7 @@ // SPDX-License-Identifier: GPL-2.0 +#include #include +#include #include #include #include @@ -16,6 +18,7 @@ #include "symbol.h" #include "unwind.h" #include "callchain.h" +#include "dwarf-regs.h" =20 #include =20 @@ -51,6 +54,7 @@ struct thread *thread__new(pid_t pid, pid_t tid) thread__set_ppid(thread, -1); thread__set_cpu(thread, -1); thread__set_guest_cpu(thread, -1); + thread__set_e_machine(thread, EM_NONE); thread__set_lbr_stitch_enable(thread, false); INIT_LIST_HEAD(thread__namespaces_list(thread)); INIT_LIST_HEAD(thread__comm_list(thread)); @@ -423,6 +427,82 @@ void thread__find_cpumode_addr_location(struct thread = *thread, u64 addr, } } =20 +static uint16_t read_proc_e_machine_for_pid(pid_t pid) +{ + char path[6 /* "/proc/" */ + 11 /* max length of pid */ + 5 /* "/exe\0" *= /]; + int fd; + uint16_t e_machine =3D EM_NONE; + + snprintf(path, sizeof(path), "/proc/%d/exe", pid); + fd =3D open(path, O_RDONLY); + if (fd >=3D 0) { + _Static_assert(offsetof(Elf32_Ehdr, e_machine) =3D=3D 18, "Unexpected of= fset"); + _Static_assert(offsetof(Elf64_Ehdr, e_machine) =3D=3D 18, "Unexpected of= fset"); + if (pread(fd, &e_machine, sizeof(e_machine), 18) !=3D sizeof(e_machine)) + e_machine =3D EM_NONE; + close(fd); + } + return e_machine; +} + +static int thread__e_machine_callback(struct map *map, void *machine) +{ + struct dso *dso =3D map__dso(map); + + _Static_assert(0 =3D=3D EM_NONE, "Unexpected EM_NONE"); + if (!dso) + return EM_NONE; + + return dso__e_machine(dso, machine); +} + +uint16_t thread__e_machine(struct thread *thread, struct machine *machine) +{ + pid_t tid, pid; + uint16_t e_machine =3D RC_CHK_ACCESS(thread)->e_machine; + + if (e_machine !=3D EM_NONE) + return e_machine; + + tid =3D thread__tid(thread); + pid =3D thread__pid(thread); + if (pid !=3D tid) { + struct thread *parent =3D machine__findnew_thread(machine, pid, pid); + + if (parent) { + e_machine =3D thread__e_machine(parent, machine); + thread__set_e_machine(thread, e_machine); + return e_machine; + } + /* Something went wrong, fallback. */ + } + /* Reading on the PID thread. First try to find from the maps. */ + e_machine =3D maps__for_each_map(thread__maps(thread), + thread__e_machine_callback, + machine); + if (e_machine =3D=3D EM_NONE) { + /* Maps failed, perhaps we're live with map events disabled. */ + bool is_live =3D machine->machines =3D=3D NULL; + + if (!is_live) { + /* Check if the session has a data file. */ + struct perf_session *session =3D container_of(machine->machines, + struct perf_session, + machines); + + is_live =3D !!session->data; + } + /* Read from /proc/pid/exe if live. */ + if (is_live) + e_machine =3D read_proc_e_machine_for_pid(pid); + } + if (e_machine !=3D EM_NONE) + thread__set_e_machine(thread, e_machine); + else + e_machine =3D EM_HOST; + return e_machine; +} + struct thread *thread__main_thread(struct machine *machine, struct thread = *thread) { if (thread__pid(thread) =3D=3D thread__tid(thread)) diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h index 6cbf6eb2812e..cd574a896418 100644 --- a/tools/perf/util/thread.h +++ b/tools/perf/util/thread.h @@ -60,7 +60,11 @@ DECLARE_RC_STRUCT(thread) { struct srccode_state srccode_state; bool filter; int filter_entry_depth; - + /** + * @e_machine: The ELF EM_* associated with the thread. EM_NONE if not + * computed. + */ + uint16_t e_machine; /* LBR call stack stitch */ bool lbr_stitch_enable; struct lbr_stitch *lbr_stitch; @@ -302,6 +306,14 @@ static inline void thread__set_filter_entry_depth(stru= ct thread *thread, int dep RC_CHK_ACCESS(thread)->filter_entry_depth =3D depth; } =20 +uint16_t thread__e_machine(struct thread *thread, struct machine *machine); + +static inline void thread__set_e_machine(struct thread *thread, uint16_t e= _machine) +{ + RC_CHK_ACCESS(thread)->e_machine =3D e_machine; +} + + static inline bool thread__lbr_stitch_enable(const struct thread *thread) { return RC_CHK_ACCESS(thread)->lbr_stitch_enable; --=20 2.48.1.711.g2feabab25a-goog