From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from nx241.node02.secure-mailgate.com (nx241.node02.secure-mailgate.com [192.162.87.241]) by sourceware.org (Postfix) with ESMTPS id 64DEC385703A for ; Mon, 31 May 2021 21:33:33 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 64DEC385703A Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=trande.de Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=zied.guermazi@trande.de Received: from host202.checkdomain.de ([185.137.168.148]) by node02.secure-mailgate.com with esmtps (TLSv1.2:AES128-GCM-SHA256:128) (Exim 4.92) (envelope-from ) id 1lnpXO-00AeWC-4v; Mon, 31 May 2021 23:33:31 +0200 X-SecureMailgate-Identity: zied.guermazi@trande.de;host202.checkdomain.de Received: from Trande0001.fritz.box (x4dbe295e.dyn.telefonica.de [77.190.41.94]) (Authenticated sender: zied.guermazi@trande.de) by host202.checkdomain.de (Postfix) with ESMTPSA id 58921300416; Mon, 31 May 2021 23:33:29 +0200 (CEST) X-SecureMailgate-Identity: zied.guermazi@trande.de;host202.checkdomain.de From: Zied Guermazi To: gdb-patches@sourceware.org, markus.t.metzger@intel.com Cc: Zied Guermazi Subject: [PATCH v6 4/7] start/stop btrace with coresight etm and collect etm buffer on linux os Date: Mon, 31 May 2021 23:33:04 +0200 Message-Id: <20210531213307.275079-5-zied.guermazi@trande.de> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210531213307.275079-1-zied.guermazi@trande.de> References: <20210531213307.275079-1-zied.guermazi@trande.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-PPP-Message-ID: <20210531213329.2006046.82774@host202.checkdomain.de> X-PPP-Vhost: trande.de X-Originating-IP: 185.137.168.148 X-SecureMailgate-Domain: host202.checkdomain.de X-SecureMailgate-Username: 185.137.168.148 Authentication-Results: secure-mailgate.com; auth=pass smtp.auth=185.137.168.148@host202.checkdomain.de X-SecureMailgate-Outgoing-Class: ham X-SecureMailgate-Outgoing-Evidence: SB/global_tokens (1.58755094404e-07) X-Recommended-Action: accept X-Filter-ID: Pt3MvcO5N4iKaDQ5O6lkdGlMVN6RH8bjRMzItlySaT81yp3xo0C6ULPI/0BmB0LuPUtbdvnXkggZ 3YnVId/Y5jcf0yeVQAvfjHznO7+bT5xepKJyYLZISh0ScmnJxtOQL++T0fzDkcbraJCnPSgcQrqW ghmgrvbuYBMbgPFqhEjKF590ee3aGyyzch48U9RYPumU89c8OaxcWLmp7ynpEu9maBc81kIfJhvX H9spB9XasE0yYSwoSJtDBJTXEF44+qKA9WNimSzzMEEnsLmJnD3bQmEqUddg4pDcHxi62gxzSOZO aYOlkYc6lCBjGxXRtrdIeJGUu23VykQIijZdTKZmzPG0W5jwUw6mKTNN5a5y8oFzlZDzSFMZMCEJ KqX33HjrAG8VuBgM4i9bc+OM5H6YFrhxVw5i30CZMe0+JKoB15eMIME6iZU0/33rc4pTBldNoc4/ ugpbufbubK+x4vA/QHsSr98zh4ylHHSOvF4EizIlMC06U8aFKFbkglvNo7UbuWzwvM5eRjzlfUYD MWFgOK8gW+hazh84oBeMtGGs+REr5it4yuwWmXN5FmKajBUnmlmmmmIH8Dg80WcRp+fC5fGvBaRW nWe6WFte+h1HBQQL7n9+OTZ37LZfI/sW30YZMgUX6Z4ThlOFxTu4LUsF4GHuFWly2YtZO0AGnGQ3 T2YxzxB8woiuExubdcsml481x58OeqpgxEwDRkEDKwPt8rNcco5Lt6ku63DkksyWUQhsiRV7ToHt 3HSONnNjcxw3qqhc+N6cuEg4XWh5Fqb0FldYqp+kcqm+1aM0u7TM30nmVmKV/QL5kcJUMTdrSnGs gqBxCNOGOr+WdlOUQOgZ8kRW3yj6wqwjQ36QzRPL7Rp7sTyiVa8HG50AexxrzznCpn9MRUzzcEJz OzmIv9M+m4WpRRDP6YzwkAPgQJbZw2WK4NzRiZTDVGmt15BzNCflaPsIqsBW58vnzO6f815jeUTV cn2J2ZCvfJDOb23fT2vcHF137XvQtnB2hMEPctgzcDoFd+96Xw4QUNtTnZZhiw7af43YPLSeyfeI qT7OqoqMIvCpZajrvxuS+2n0bmim7U+d9AZiaR2WxIbRcfP4wHlqBE95R7lrKCg7FGkTm3FqRDxU q50C08gBiOmGBiFMXZsNOH+1R01VtZLf6H6YFrhxVw5i30CZMe0+JKqWmKu/Exva/4bO4tpXcmDO vZQjnSGPGpsSE/xM+RnyGGWi2HOzq/csyFjkk1RUX5M= X-Report-Abuse-To: spam@node04.secure-mailgate.com X-Spam-Status: No, score=-10.6 required=5.0 tests=BAYES_00, GIT_PATCH_0, JMQ_SPF_NEUTRAL, KAM_DMARC_STATUS, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 31 May 2021 21:33:36 -0000 This patch implement the lower layer for starting ad stopping ARM CoreSight tracing on linux targets for arm and aarch64 gdb/ChangeLog * nat/linux-btrace.h (btrace_tinfo_etm): New. (btrace_target_info): add etm. * nat/linux-btrace.c (linux_enable_bts): get page size from sysconf. (linux_enable_pt): get page size from sysconf. (perf_event_etm_event_type): New. (perf_event_etm_event_sink): New. (linux_enable_etm): New. (linux_enable_btrace): add enabling etm traces. (linux_disable_bts): get page size from sysconf. (linux_disable_pt): get page size from sysconf. (linux_disable_etm): New. (linux_disable_btrace): add disabling etm traces. (get_cpu_count): New. (cs_etm_is_etmv4): New. (cs_etm_get_register): New. (coresight_get_trace_id): New. (fill_etm_trace_params): New. (linux_fill_btrace_etm_config): New. (linux_read_etm): New. (linux_read_btrace): add reading etm traces. * arm-linux-nat.c (arm_linux_nat_target::enable_btrace): New. (arm_linux_nat_target::disable_btrace): New. (arm_linux_nat_target::teardown_btrace): New. (arm_linux_nat_target::read_btrace): New. (arm_linux_nat_target::btrace_conf): New. * aarch64-linux-nat.c (aarch64_linux_nat_target::enable_btrace): New. (aarch64_linux_nat_target::disable_btrace): New. (aarch64_linux_nat_target::teardown_btrace): New. (aarch64_linux_nat_target::read_btrace): New. (aarch64_linux_nat_target::btrace_conf): New. --- gdb/aarch64-linux-nat.c | 68 +++++++ gdb/arm-linux-nat.c | 68 +++++++ gdb/nat/linux-btrace.c | 395 ++++++++++++++++++++++++++++++++++++++-- gdb/nat/linux-btrace.h | 19 ++ 4 files changed, 537 insertions(+), 13 deletions(-) diff --git a/gdb/aarch64-linux-nat.c b/gdb/aarch64-linux-nat.c index 61224022f6a..4b629e1b3d2 100644 --- a/gdb/aarch64-linux-nat.c +++ b/gdb/aarch64-linux-nat.c @@ -35,6 +35,7 @@ #include "nat/aarch64-linux.h" #include "nat/aarch64-linux-hw-point.h" #include "nat/aarch64-sve-linux-ptrace.h" +#include "nat/linux-btrace.h" #include "elf/external.h" #include "elf/common.h" @@ -88,6 +89,17 @@ class aarch64_linux_nat_target final : public linux_nat_target /* Override the GNU/Linux post attach hook. */ void post_attach (int pid) override; + /* Override branch tracing. */ + struct btrace_target_info *enable_btrace (ptid_t ptid, + const struct btrace_config *conf) override; + void disable_btrace (struct btrace_target_info *tinfo) override; + void teardown_btrace (struct btrace_target_info *tinfo) override; + enum btrace_error read_btrace (struct btrace_data *data, + struct btrace_target_info *btinfo, + enum btrace_read_type type) override; + const struct btrace_config *btrace_conf (const struct btrace_target_info *) + override; + /* These three defer to common nat/ code. */ void low_new_thread (struct lwp_info *lp) override { aarch64_linux_new_thread (lp); } @@ -714,6 +726,62 @@ aarch64_linux_nat_target::post_attach (int pid) linux_nat_target::post_attach (pid); } +/* Enable branch tracing. */ + +struct btrace_target_info * +aarch64_linux_nat_target::enable_btrace (ptid_t ptid, + const struct btrace_config *conf) +{ + struct btrace_target_info *tinfo = nullptr; + try + { + tinfo = linux_enable_btrace (ptid, conf); + } + catch (const gdb_exception_error &exception) + { + error (_("Could not enable branch tracing for %s: %s"), + target_pid_to_str (ptid).c_str (), exception.what ()); + } + + return tinfo; +} + +/* Disable branch tracing. */ + +void +aarch64_linux_nat_target::disable_btrace (struct btrace_target_info *tinfo) +{ + enum btrace_error errcode = linux_disable_btrace (tinfo); + + if (errcode != BTRACE_ERR_NONE) + error (_("Could not disable branch tracing.")); +} + +/* Teardown branch tracing. */ + +void +aarch64_linux_nat_target::teardown_btrace (struct btrace_target_info *tinfo) +{ + /* Ignore errors. */ + linux_disable_btrace (tinfo); +} + +enum btrace_error +aarch64_linux_nat_target::read_btrace (struct btrace_data *data, + struct btrace_target_info *btinfo, + enum btrace_read_type type) +{ + return linux_read_btrace (data, btinfo, type); +} + +/* See to_btrace_conf in target.h. */ + +const struct btrace_config * +aarch64_linux_nat_target::btrace_conf (const struct btrace_target_info *btinfo) +{ + return linux_btrace_conf (btinfo); +} + /* Implement the "read_description" target_ops method. */ const struct target_desc * diff --git a/gdb/arm-linux-nat.c b/gdb/arm-linux-nat.c index 880ac0da044..32631b33328 100644 --- a/gdb/arm-linux-nat.c +++ b/gdb/arm-linux-nat.c @@ -39,6 +39,7 @@ #include #include "nat/linux-ptrace.h" +#include "nat/linux-btrace.h" #include "linux-tdep.h" /* Prototypes for supply_gregset etc. */ @@ -95,6 +96,17 @@ class arm_linux_nat_target final : public linux_nat_target const struct target_desc *read_description () override; + /* Override branch tracing. */ + struct btrace_target_info *enable_btrace (ptid_t ptid, + const struct btrace_config *conf) override; + void disable_btrace (struct btrace_target_info *tinfo) override; + void teardown_btrace (struct btrace_target_info *tinfo) override; + enum btrace_error read_btrace (struct btrace_data *data, + struct btrace_target_info *btinfo, + enum btrace_read_type type) override; + const struct btrace_config *btrace_conf (const struct btrace_target_info *) + override; + /* Override linux_nat_target low methods. */ /* Handle thread creation and exit. */ @@ -1190,6 +1202,62 @@ arm_linux_nat_target::watchpoint_addr_within_range (CORE_ADDR addr, return start <= addr && start + length - 1 >= addr; } +/* Enable branch tracing. */ + +struct btrace_target_info * +arm_linux_nat_target::enable_btrace (ptid_t ptid, + const struct btrace_config *conf) +{ + struct btrace_target_info *tinfo = nullptr; + try + { + tinfo = linux_enable_btrace (ptid, conf); + } + catch (const gdb_exception_error &exception) + { + error (_("Could not enable branch tracing for %s: %s"), + target_pid_to_str (ptid).c_str (), exception.what ()); + } + + return tinfo; +} + +/* Disable branch tracing. */ + +void +arm_linux_nat_target::disable_btrace (struct btrace_target_info *tinfo) +{ + enum btrace_error errcode = linux_disable_btrace (tinfo); + + if (errcode != BTRACE_ERR_NONE) + error (_("Could not disable branch tracing.")); +} + +/* Teardown branch tracing. */ + +void +arm_linux_nat_target::teardown_btrace (struct btrace_target_info *tinfo) +{ + /* Ignore errors. */ + linux_disable_btrace (tinfo); +} + +enum btrace_error +arm_linux_nat_target::read_btrace (struct btrace_data *data, + struct btrace_target_info *btinfo, + enum btrace_read_type type) +{ + return linux_read_btrace (data, btinfo, type); +} + +/* See to_btrace_conf in target.h. */ + +const struct btrace_config * +arm_linux_nat_target::btrace_conf (const struct btrace_target_info *btinfo) +{ + return linux_btrace_conf (btinfo); +} + /* Handle thread creation. We need to copy the breakpoints and watchpoints in the parent thread to the child thread. */ void diff --git a/gdb/nat/linux-btrace.c b/gdb/nat/linux-btrace.c index 324f7ef0407..9ef182d774a 100644 --- a/gdb/nat/linux-btrace.c +++ b/gdb/nat/linux-btrace.c @@ -32,6 +32,10 @@ #include +#if defined (HAVE_LIBOPENCSD_C_API) +# include +#endif + #if HAVE_LINUX_PERF_EVENT_H && defined(SYS_perf_event_open) #include #include @@ -483,10 +487,11 @@ linux_enable_bts (ptid_t ptid, const struct btrace_config_bts *conf) scoped_fd fd (syscall (SYS_perf_event_open, &bts->attr, pid, -1, -1, 0)); if (fd.get () < 0) diagnose_perf_event_open_fail (); + long page_size = sysconf (_SC_PAGESIZE); /* Convert the requested size in bytes to pages (rounding up). */ - pages = ((size_t) conf->size / PAGE_SIZE - + ((conf->size % PAGE_SIZE) == 0 ? 0 : 1)); + pages = ((size_t) conf->size / page_size + + ((conf->size % page_size) == 0 ? 0 : 1)); /* We need at least one page. */ if (pages == 0) pages = 1; @@ -505,17 +510,17 @@ linux_enable_bts (ptid_t ptid, const struct btrace_config_bts *conf) size_t length; __u64 data_size; - data_size = (__u64) pages * PAGE_SIZE; + data_size = (__u64) pages * page_size; /* Don't ask for more than we can represent in the configuration. */ if ((__u64) UINT_MAX < data_size) continue; size = (size_t) data_size; - length = size + PAGE_SIZE; + length = size + page_size; /* Check for overflows. */ - if ((__u64) length != data_size + PAGE_SIZE) + if ((__u64) length != data_size + page_size) continue; errno = 0; @@ -530,7 +535,7 @@ linux_enable_bts (ptid_t ptid, const struct btrace_config_bts *conf) struct perf_event_mmap_page *header = (struct perf_event_mmap_page *) data.get (); - data_offset = PAGE_SIZE; + data_offset = page_size; #if defined (PERF_ATTR_SIZE_VER5) if (offsetof (struct perf_event_mmap_page, data_size) <= header->size) @@ -613,7 +618,8 @@ linux_enable_pt (ptid_t ptid, const struct btrace_config_pt *conf) diagnose_perf_event_open_fail (); /* Allocate the configuration page. */ - scoped_mmap data (nullptr, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, + long page_size = sysconf (_SC_PAGESIZE); + scoped_mmap data (nullptr, page_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd.get (), 0); if (data.get () == MAP_FAILED) error (_("Failed to map trace user page: %s."), safe_strerror (errno)); @@ -624,8 +630,8 @@ linux_enable_pt (ptid_t ptid, const struct btrace_config_pt *conf) header->aux_offset = header->data_offset + header->data_size; /* Convert the requested size in bytes to pages (rounding up). */ - pages = ((size_t) conf->size / PAGE_SIZE - + ((conf->size % PAGE_SIZE) == 0 ? 0 : 1)); + pages = ((size_t) conf->size / page_size + + ((conf->size % page_size) == 0 ? 0 : 1)); /* We need at least one page. */ if (pages == 0) pages = 1; @@ -644,7 +650,7 @@ linux_enable_pt (ptid_t ptid, const struct btrace_config_pt *conf) size_t length; __u64 data_size; - data_size = (__u64) pages * PAGE_SIZE; + data_size = (__u64) pages * page_size; /* Don't ask for more than we can represent in the configuration. */ if ((__u64) UINT_MAX < data_size) @@ -689,6 +695,154 @@ linux_enable_pt (ptid_t ptid, const struct btrace_config_pt *conf) #endif /* !defined (PERF_ATTR_SIZE_VER5) */ +/* Determine the etm event type. */ + +static int +perf_event_etm_event_type () +{ + static const char filename[] = "/sys/bus/event_source/devices/cs_etm/type"; + + errno = 0; + gdb_file_up file = gdb_fopen_cloexec (filename, "r"); + if (file.get () == nullptr) + error (_("Failed to open %s: %s."), filename, safe_strerror (errno)); + + int type, found = fscanf (file.get (), "%d", &type); + if (found != 1) + error (_("Failed to read the ETM event type from %s."), filename); + + return type; +} + +/* Get the sink hash to use in the event attributes. */ + +static unsigned int +perf_event_etm_event_sink (const struct btrace_config_etm *conf) +{ + char filename[PATH_MAX]; + + snprintf (filename, PATH_MAX, + "/sys/bus/event_source/devices/cs_etm/sinks/%s", conf->sink); + errno = 0; + gdb_file_up file = gdb_fopen_cloexec (filename, "r"); + if (file.get () == nullptr) + error (_("Failed to open %s: %s."), filename, safe_strerror (errno)); + + unsigned int sink; + int found = fscanf (file.get (), "0x%x", &sink); + if (found != 1) + error (_("Failed to read the ETM sink from %s."), filename); + + return sink; +} + +/* Enable ARM CoreSight ETM tracing. */ + +static struct btrace_target_info * +linux_enable_etm (ptid_t ptid, const struct btrace_config_etm *conf) +{ + struct btrace_tinfo_etm *etm; + size_t pages; + int pid, pg; + + pid = ptid.lwp (); + if (pid == 0) + pid = ptid.pid (); + + gdb::unique_xmalloc_ptr tinfo + (XCNEW (btrace_target_info)); + tinfo->ptid = ptid; + + tinfo->conf.format = BTRACE_FORMAT_ETM; + etm = &tinfo->variant.etm; + + etm->attr.type = perf_event_etm_event_type (); + etm->attr.size = sizeof (etm->attr); + + etm->attr.sample_type = PERF_SAMPLE_CPU; + etm->attr.read_format = PERF_FORMAT_ID; + etm->attr.sample_id_all = 1; + etm->attr.enable_on_exec = 1; + etm->attr.exclude_kernel = 1; + etm->attr.exclude_hv = 1; + etm->attr.exclude_idle = 1; + if (conf->sink != nullptr) + { + if (strcmp (conf->sink, "default") != 0) + etm->attr.config2 = perf_event_etm_event_sink (conf); + } + + errno = 0; + scoped_fd fd (syscall (SYS_perf_event_open, &etm->attr, pid, -1, -1, 0)); + if (fd.get () < 0) + diagnose_perf_event_open_fail (); + + /* Allocate the configuration page. */ + long page_size = sysconf (_SC_PAGESIZE); + scoped_mmap data (nullptr, page_size, PROT_READ | PROT_WRITE, MAP_SHARED, + fd.get (), 0); + if (data.get () == MAP_FAILED) + error (_("Failed to map trace user page: %s."), safe_strerror (errno)); + + struct perf_event_mmap_page *header = (struct perf_event_mmap_page *) + data.get (); + + header->aux_offset = header->data_offset + header->data_size; + /* Convert the requested size in bytes to pages (rounding up). */ + pages = ((size_t) conf->size / page_size + + ((conf->size % page_size) == 0 ? 0 : 1)); + /* We need at least one page. */ + if (pages == 0) + pages = 1; + + /* The buffer size can be requested in powers of two pages. Adjust PAGES + to the next power of two. */ + for (pg = 0; pages != ((size_t) 1 << pg); ++pg) + if ((pages & ((size_t) 1 << pg)) != 0) + pages += ((size_t) 1 << pg); + + /* We try to allocate the requested size. + If that fails, try to get as much as we can. */ + scoped_mmap aux; + for (; pages > 0; pages >>= 1) + { + size_t length; + __u64 data_size; + data_size = (__u64) pages * page_size; + + /* Don't ask for more than we can represent in the configuration. */ + if ((__u64) UINT_MAX < data_size) + continue; + + length = (size_t) data_size; + + /* Check for overflows. */ + if ((__u64) length != data_size) + continue; + + header->aux_size = data_size; + + errno = 0; + aux.reset (nullptr, length, PROT_READ, MAP_SHARED, fd.get (), + header->aux_offset); + if (aux.get () != MAP_FAILED) + break; + } + if (pages == 0) + error (_("Failed to map trace buffer: %s."), safe_strerror (errno)); + + etm->etm.size = aux.size (); + etm->etm.mem = (const uint8_t *) aux.release (); + etm->etm.data_head = &header->aux_head; + etm->etm.last_head = header->aux_tail; + etm->header = (struct perf_event_mmap_page *) data.release (); + gdb_assert (etm->header == header); + etm->file = fd.release (); + + tinfo->conf.etm.size = (unsigned int) etm->etm.size; + return tinfo.release (); +} + /* See linux-btrace.h. */ struct btrace_target_info * @@ -707,6 +861,10 @@ linux_enable_btrace (ptid_t ptid, const struct btrace_config *conf) case BTRACE_FORMAT_PT: return linux_enable_pt (ptid, &conf->pt); + + case BTRACE_FORMAT_ETM: + return linux_enable_etm (ptid, &conf->etm); + } } @@ -715,7 +873,8 @@ linux_enable_btrace (ptid_t ptid, const struct btrace_config *conf) static enum btrace_error linux_disable_bts (struct btrace_tinfo_bts *tinfo) { - munmap((void *) tinfo->header, tinfo->bts.size + PAGE_SIZE); + long page_size = sysconf (_SC_PAGESIZE); + munmap ((void *) tinfo->header, tinfo->bts.size + page_size); close (tinfo->file); return BTRACE_ERR_NONE; @@ -726,8 +885,22 @@ linux_disable_bts (struct btrace_tinfo_bts *tinfo) static enum btrace_error linux_disable_pt (struct btrace_tinfo_pt *tinfo) { - munmap((void *) tinfo->pt.mem, tinfo->pt.size); - munmap((void *) tinfo->header, PAGE_SIZE); + long page_size = sysconf (_SC_PAGESIZE); + munmap ((void *) tinfo->pt.mem, tinfo->pt.size); + munmap ((void *) tinfo->header, page_size); + close (tinfo->file); + + return BTRACE_ERR_NONE; +} + +/* Disable ARM CoreSight ETM tracing. */ + +static enum btrace_error +linux_disable_etm (struct btrace_tinfo_etm *tinfo) +{ + long page_size = sysconf (_SC_PAGESIZE); + munmap ((void *) tinfo->etm.mem, tinfo->etm.size); + munmap ((void *) tinfo->header, page_size); close (tinfo->file); return BTRACE_ERR_NONE; @@ -753,6 +926,10 @@ linux_disable_btrace (struct btrace_target_info *tinfo) case BTRACE_FORMAT_PT: errcode = linux_disable_pt (&tinfo->variant.pt); break; + + case BTRACE_FORMAT_ETM: + errcode = linux_disable_etm (&tinfo->variant.etm); + break; } if (errcode == BTRACE_ERR_NONE) @@ -898,6 +1075,190 @@ linux_read_pt (struct btrace_data_pt *btrace, internal_error (__FILE__, __LINE__, _("Unknown btrace read type.")); } +/* Return the number of CPUs that are present. */ + +static int +get_cpu_count (void) +{ + static const char filename[] = "/sys/devices/system/cpu/present"; + + gdb_file_up file = gdb_fopen_cloexec (filename, "r"); + if (file.get () == nullptr) + error (_("Failed to open %s: %s."), filename, safe_strerror (errno)); + + fseek (file.get (), 0, SEEK_END); + int length = ftell (file.get ()); + fseek (file.get (), 0, SEEK_SET); + + char *buffer = (char *) xmalloc (length+1); + + length = fread (buffer, 1, length, file.get ()); + buffer[length]='\0'; + while ((--length) != 0) + { + if ((buffer[length] == ',') || (buffer[length] == '-')) + { + length++; + break; + } + } + + int cpu_count; + int found = sscanf (&buffer[length], "%d", &cpu_count); + if (found < 1) + error (_("Failed to get cpu count in %s: %s."), + buffer, safe_strerror (errno)); + + cpu_count ++; + return (cpu_count); +} + +/* Check if the ETM is an etmv4. */ + +static bool +cs_etm_is_etmv4 (int cpu) +{ + char filename[PATH_MAX]; + snprintf (filename, PATH_MAX, + "/sys/bus/event_source/devices/cs_etm/cpu%d/trcidr/trcidr0", cpu); + errno = 0; + gdb_file_up file = gdb_fopen_cloexec (filename, "r"); + if (file.get () == nullptr) + return false; + + return true; +} + +/* Get etm configuration register from sys filesystem. */ + +static uint32_t +cs_etm_get_register (int cpu, const char *path) +{ + char filename[PATH_MAX]; + + /* Get coresight register from sysfs. */ + snprintf (filename, PATH_MAX, + "/sys/bus/event_source/devices/cs_etm/cpu%d/%s", cpu, path); + errno = 0; + gdb_file_up file = gdb_fopen_cloexec (filename, "r"); + if (file.get () == nullptr) + error (_("Failed to open %s: %s."), filename, safe_strerror (errno)); + + uint32_t val = 0; + + int found = fscanf (file.get (), "0x%x", &val); + if (found != 1) + error (_("Failed to read coresight register from %s."), filename); + return val; +} + +#define CORESIGHT_ETM_PMU_SEED 0x10 + +/* Calculate trace_id for this cpu + to be kept aligned with coresight-pmu.h. */ + +static inline int +coresight_get_trace_id (int cpu) +{ + return (CORESIGHT_ETM_PMU_SEED + (cpu * 2)); +} + +/* PTMs ETMIDR[11:8] set to b0011. */ +#define ETMIDR_PTM_VERSION 0x00000300 + +/* Collect and fill etm trace parameter. */ + +static void +fill_etm_trace_params (struct cs_etm_trace_params *etm_trace_params, int cpu) +{ + if (cs_etm_is_etmv4 (cpu) == true) + { + etm_trace_params->arch_ver = ARCH_V8; + etm_trace_params->core_profile = profile_CortexA; + etm_trace_params->protocol = OCSD_PROTOCOL_ETMV4I; + /* This is the parameter passed in etm->attr.config in the call to + perf_event_open remapped according to linux/coresight-pmu.h. */ + etm_trace_params->etmv4.reg_configr = 0; + etm_trace_params->etmv4.reg_idr0 + = cs_etm_get_register (cpu, "trcidr/trcidr0"); + etm_trace_params->etmv4.reg_idr1 + = cs_etm_get_register (cpu, "trcidr/trcidr1"); + etm_trace_params->etmv4.reg_idr2 + = cs_etm_get_register (cpu, "trcidr/trcidr2"); + etm_trace_params->etmv4.reg_idr8 + = cs_etm_get_register (cpu, "trcidr/trcidr8"); + etm_trace_params->etmv4.reg_traceidr = coresight_get_trace_id (cpu); + } + else + { + etm_trace_params->arch_ver = ARCH_V7; + etm_trace_params->core_profile = profile_CortexA; + etm_trace_params->protocol + = (etm_trace_params->etmv3.reg_idr & ETMIDR_PTM_VERSION) + == ETMIDR_PTM_VERSION ? OCSD_PROTOCOL_PTM : OCSD_PROTOCOL_ETMV3; + etm_trace_params->etmv3.reg_ccer + = cs_etm_get_register (cpu, "mgmt/etmccer"); + etm_trace_params->etmv3.reg_ctrl + = cs_etm_get_register (cpu, "mgmt/etmcr"); + etm_trace_params->etmv3.reg_idr + = cs_etm_get_register (cpu, "mgmt/etmidr"); + etm_trace_params->etmv3.reg_trc_id + = cs_etm_get_register (cpu, "traceid"); + } +} + +static void +linux_fill_btrace_etm_config (struct btrace_target_info *tinfo, + struct btrace_data_etm_config *conf) +{ + + cs_etm_trace_params etm_trace_params; + conf->cpu_count = get_cpu_count (); + conf->etm_trace_params = new std::vector; + for (int i = 0; i < conf->cpu_count; i++) + { + fill_etm_trace_params (&etm_trace_params,i); + conf->etm_trace_params->push_back (etm_trace_params); + } + + conf->etm_decoder_params.formatted = 1; + conf->etm_decoder_params.fsyncs = 0; + conf->etm_decoder_params.hsyncs = 0; + conf->etm_decoder_params.frame_aligned = 0; + conf->etm_decoder_params.reset_on_4x_sync = 1; +} + +static enum btrace_error +linux_read_etm (struct btrace_data_etm *btrace, + struct btrace_target_info *tinfo, + enum btrace_read_type type) +{ + struct perf_event_buffer *etm; + etm = &tinfo->variant.etm.etm; + + linux_fill_btrace_etm_config (tinfo, &btrace->config); + + switch (type) + { + case BTRACE_READ_DELTA: + /* We don't support delta reads. The data head (i.e. aux_head) wraps + around to stay inside the aux buffer. */ + return BTRACE_ERR_NOT_SUPPORTED; + + case BTRACE_READ_NEW: + if (!perf_event_new_data (etm)) + return BTRACE_ERR_NONE; + + /* Fall through. */ + case BTRACE_READ_ALL: + perf_event_read_all (etm, &(btrace->data),&(btrace->size)); + return BTRACE_ERR_NONE; + } + + internal_error (__FILE__, __LINE__, _("Unkown btrace read type.")); +} + + /* See linux-btrace.h. */ enum btrace_error @@ -924,6 +1285,14 @@ linux_read_btrace (struct btrace_data *btrace, btrace->variant.pt.size = 0; return linux_read_pt (&btrace->variant.pt, tinfo, type); + + case BTRACE_FORMAT_ETM: + /* We read btrace in ARM CoreSight ETM Trace format. */ + btrace->format = BTRACE_FORMAT_ETM; + btrace->variant.etm.data = NULL; + btrace->variant.etm.size = 0; + + return linux_read_etm (&btrace->variant.etm, tinfo, type); } internal_error (__FILE__, __LINE__, _("Unkown branch trace format.")); diff --git a/gdb/nat/linux-btrace.h b/gdb/nat/linux-btrace.h index 607182da144..3038d2f45a0 100644 --- a/gdb/nat/linux-btrace.h +++ b/gdb/nat/linux-btrace.h @@ -78,6 +78,22 @@ struct btrace_tinfo_pt /* The trace perf event buffer. */ struct perf_event_buffer pt; }; + +/* Branch trace target information for ARM CoreSight ETM Trace. */ +struct btrace_tinfo_etm +{ + /* The Linux perf_event configuration for collecting the branch trace. */ + struct perf_event_attr attr; + + /* The perf event file. */ + int file; + + /* The perf event configuration page. */ + volatile struct perf_event_mmap_page *header; + + /* The trace perf event buffer. */ + struct perf_event_buffer etm; +}; #endif /* HAVE_LINUX_PERF_EVENT_H */ /* Branch trace target information per thread. */ @@ -98,6 +114,9 @@ struct btrace_target_info /* CONF.FORMAT == BTRACE_FORMAT_PT. */ struct btrace_tinfo_pt pt; + + /* CONF.FORMAT == BTRACE_FORMAT_ETM. */ + struct btrace_tinfo_etm etm; } variant; #endif /* HAVE_LINUX_PERF_EVENT_H */ }; -- 2.25.1