[DTrace-devel] [PATCH 08/15 v2] Update cpu handling to also retrieve num_possible_cpus and chip id
Kris Van Hees
kris.van.hees at oracle.com
Fri May 29 10:59:38 PDT 2020
The code used to populate the list of online CPUs was only recording
the CPU ids. In order to support the cpuinfo_t information needed
for the curcpu D variable we need additional information. This patch
adds code to obtain the chip id for each CPU and also the number of
possible CPUs on the system..
The cpuinfo_t structure definition is added to include/dtrace/conf.h,
and members in dtrace_conf_t have been updated (better naming, type
updates, and adding num_possible_cpus). The renaming of numcpus to
num_online_cpus required updates to various source code files that use
it.
The list of online CPU ids has been converted into a list of cpuinfo_t
structures.
The dt_conf_init() function has been moved from dt_subr.c to its own
file.
Signed-off-by: Kris Van Hees <kris.van.hees at oracle.com>
---
include/dtrace/conf.h | 27 ++++++---
libdtrace/Build | 10 ++--
libdtrace/dt_bpf.c | 2 +-
libdtrace/dt_conf.c | 122 +++++++++++++++++++++++++++++++++++++++++
libdtrace/dt_consume.c | 4 +-
libdtrace/dt_open.c | 14 +++--
libdtrace/dt_peb.c | 9 +--
libdtrace/dt_subr.c | 85 ----------------------------
8 files changed, 161 insertions(+), 112 deletions(-)
create mode 100644 libdtrace/dt_conf.c
diff --git a/include/dtrace/conf.h b/include/dtrace/conf.h
index d40a781b..90195835 100644
--- a/include/dtrace/conf.h
+++ b/include/dtrace/conf.h
@@ -16,18 +16,27 @@
#include <dtrace/universal.h>
#include <dtrace/conf_defines.h>
+typedef struct cpuinfo {
+ processorid_t cpu_id;
+ psetid_t cpu_pset;
+ chipid_t cpu_chip;
+ lgrp_id_t cpu_lgrp;
+ void *cpu_info;
+} cpuinfo_t;
+
typedef struct dtrace_conf {
- uint_t numcpus; /* number of online CPUs */
- processorid_t maxcpuid; /* highest CPU id */
- processorid_t *cpuids; /* list of CPU ids */
+ uint32_t num_possible_cpus; /* number of possible CPUs */
+ uint32_t num_online_cpus; /* number of online CPUs */
+ processorid_t max_cpuid; /* highest CPU id */
+ cpuinfo_t *cpus; /* CPU info structs */
/* FIXME: Are these actually still necessary for our purposes? */
- uint_t dtc_difversion; /* supported DIF version */
- uint_t dtc_difintregs; /* # of DIF integer registers */
- uint_t dtc_diftupregs; /* # of DIF tuple registers */
- uint_t dtc_ctfmodel; /* CTF data model */
- uint_t dtc_maxbufs; /* max # of buffers */
- uint_t dtc_pad[7]; /* reserved for future use */
+ uint32_t dtc_difversion; /* supported DIF version */
+ uint32_t dtc_difintregs; /* # of DIF integer registers */
+ uint32_t dtc_diftupregs; /* # of DIF tuple registers */
+ uint32_t dtc_ctfmodel; /* CTF data model */
+ uint32_t dtc_maxbufs; /* max # of buffers */
+ uint32_t dtc_pad[7]; /* reserved for future use */
} dtrace_conf_t;
#endif /* _DTRACE_CONF_H */
diff --git a/libdtrace/Build b/libdtrace/Build
index 684d8ebc..1fe41d53 100644
--- a/libdtrace/Build
+++ b/libdtrace/Build
@@ -11,11 +11,11 @@ libdtrace-build_CPPFLAGS = -Ilibdtrace -Ilibproc -Iuts/intel -Ilibdtrace/$(ARCHI
libdtrace-build_TARGET = libdtrace
libdtrace-build_DIR := $(current-dir)
libdtrace-build_SOURCES = dt_lex.c dt_aggregate.c dt_as.c dt_bpf.c \
- dt_buf.c dt_cc.c dt_cg.c dt_consume.c dt_debug.c \
- dt_decl.c dt_dis.c dt_dlibs.c dt_dof.c dt_error.c \
- dt_errtags.c dt_grammar.c dt_handle.c dt_htab.c \
- dt_ident.c dt_link.c dt_kernel_module.c dt_list.c \
- dt_map.c dt_module.c dt_names.c dt_open.c \
+ dt_buf.c dt_cc.c dt_cg.c dt_conf.c dt_consume.c \
+ dt_debug.c dt_decl.c dt_dis.c dt_dlibs.c dt_dof.c \
+ dt_error.c dt_errtags.c dt_grammar.c dt_handle.c \
+ dt_htab.c dt_ident.c dt_link.c dt_kernel_module.c \
+ dt_list.c dt_map.c dt_module.c dt_names.c dt_open.c \
dt_options.c dt_parser.c dt_pcap.c dt_pcb.c \
dt_pid.c dt_pragma.c dt_printf.c dt_probe.c \
dt_proc.c dt_program.c dt_provider.c dt_regset.c \
diff --git a/libdtrace/dt_bpf.c b/libdtrace/dt_bpf.c
index 97d33ae2..a0dd0ef0 100644
--- a/libdtrace/dt_bpf.c
+++ b/libdtrace/dt_bpf.c
@@ -146,7 +146,7 @@ dt_bpf_gmap_create(dtrace_hdl_t *dtp, uint_t probec)
/* Create global maps as long as there are no errors. */
if (create_gmap(dtp, "buffers", BPF_MAP_TYPE_PERF_EVENT_ARRAY,
sizeof(uint32_t), sizeof(uint32_t),
- dtp->dt_conf.numcpus) == -1)
+ dtp->dt_conf.num_online_cpus) == -1)
return -1; /* dt_errno is set for us */
if (create_gmap(dtp, "mem", BPF_MAP_TYPE_PERCPU_ARRAY,
diff --git a/libdtrace/dt_conf.c b/libdtrace/dt_conf.c
new file mode 100644
index 00000000..890198a8
--- /dev/null
+++ b/libdtrace/dt_conf.c
@@ -0,0 +1,122 @@
+/*
+ * Oracle Linux DTrace.
+ * Copyright (c) 2020, Oracle and/or its affiliates. All rights reserved.
+ * Licensed under the Universal Permissive License v 1.0 as shown at
+ * http://oss.oracle.com/licenses/upl.
+ */
+
+#include <assert.h>
+#include <errno.h>
+#include <stdio.h>
+#include <dt_impl.h>
+
+#define SYSFS_CPU "/sys/devices/system/cpu/"
+#define ONLINE_CPUS SYSFS_CPU "online"
+#define POSSIBLE_CPUS SYSFS_CPU "possible"
+#define CPU_CHIP_ID SYSFS_CPU "cpu%d/topology/physical_package_id"
+
+static uint32_t
+dt_cpuinfo_read(dtrace_hdl_t *dtp, const char *fn, cpuinfo_t **cip)
+{
+ FILE *fp;
+ int cnt = 0;
+ cpuinfo_t *ci = NULL;
+
+ uint32_t num, start;
+ int range = 0;
+ char c[2];
+
+ fp = fopen(fn, "r");
+ if (fp == NULL)
+ goto out;
+
+again:
+ cnt = 0;
+ for (;;) {
+ c[0] = 0;
+ switch (fscanf(fp, "%u%1[,-]", &num, c)) {
+ case 2:
+ if (c[0] == '-') {
+ range = 1;
+ start = num;
+ continue;
+ }
+ /* fall-through */
+ case 1:
+ if (range) {
+ range = 0;
+ cnt += num - start + 1;
+ } else {
+ start = num;
+ cnt++;
+ }
+
+ if (ci) {
+ uint32_t i;
+
+ for (i = start; i <= num; i++)
+ (ci++)->cpu_id = i;
+ }
+
+ if (c[0] == ',')
+ continue;
+ default:
+ break;
+ }
+
+ break;
+ }
+
+ if (ci == NULL && cip != NULL && cnt > 0) {
+ ci = dt_calloc(dtp, cnt, sizeof(cpuinfo_t));
+ *cip = ci;
+ rewind(fp);
+ goto again;
+ }
+
+ fclose(fp);
+out:
+ return cnt;
+}
+
+void
+dt_conf_init(dtrace_hdl_t *dtp)
+{
+ size_t len;
+ char *fn;
+ int i;
+ dtrace_conf_t *conf = &dtp->dt_conf;
+ cpuinfo_t *ci;
+
+ /*
+ * Determine number of possible and online CPUs, and obtain the list of
+ * cpuinfo_t structures for the online CPUs.
+ */
+ conf->num_possible_cpus = dt_cpuinfo_read(dtp, POSSIBLE_CPUS, NULL);
+ conf->num_online_cpus = dt_cpuinfo_read(dtp, ONLINE_CPUS, &conf->cpus);
+
+ if (conf->num_online_cpus == 0 || conf->cpus == NULL)
+ return;
+
+ conf->max_cpuid = conf->cpus[conf->num_online_cpus - 1].cpu_id;
+
+ /* Retrieve the chip ID (physical_package_id) for each CPU. */
+ len = snprintf(NULL, 0, CPU_CHIP_ID, dtp->dt_conf.max_cpuid) + 1;
+ fn = dt_alloc(dtp, len);
+ if (fn == NULL)
+ return;
+
+ for (i = 0, ci = &dtp->dt_conf.cpus[0]; i < conf->num_online_cpus;
+ i++, ci++) {
+ FILE *fp;
+
+ snprintf(fn, len, CPU_CHIP_ID, ci->cpu_id);
+ fp = fopen(fn, "r");
+ if (fp != NULL) {
+ fscanf(fp, "%u", &ci->cpu_chip);
+ fclose(fp);
+ }
+ }
+
+ dt_free(dtp, fn);
+}
diff --git a/libdtrace/dt_consume.c b/libdtrace/dt_consume.c
index 5a5eb3bb..bd54ddee 100644
--- a/libdtrace/dt_consume.c
+++ b/libdtrace/dt_consume.c
@@ -2854,7 +2854,7 @@ dtrace_consume(dtrace_hdl_t *dtp, FILE *fp,
return (dt_consume_cpu(dtp, fp, dtp->dt_endedon, buf, pf, rf, arg));
#else
dtrace_optval_t timeout = dtp->dt_options[DTRACEOPT_SWITCHRATE];
- struct epoll_event events[dtp->dt_conf.numcpus];
+ struct epoll_event events[dtp->dt_conf.num_online_cpus];
int i, cnt;
/*
@@ -2863,7 +2863,7 @@ dtrace_consume(dtrace_hdl_t *dtp, FILE *fp,
* We therefore need to convert the value.
*/
timeout /= NANOSEC / MILLISEC;
- cnt = epoll_wait(dtp->dt_poll_fd, events, dtp->dt_conf.numcpus,
+ cnt = epoll_wait(dtp->dt_poll_fd, events, dtp->dt_conf.num_online_cpus,
timeout);
if (cnt < 0) {
dt_set_errno(dtp, errno);
diff --git a/libdtrace/dt_open.c b/libdtrace/dt_open.c
index 2c57a8a3..7f680419 100644
--- a/libdtrace/dt_open.c
+++ b/libdtrace/dt_open.c
@@ -547,9 +547,10 @@ inline long NULL = 0; \n\
* Default DTrace configuration.
*/
static const dtrace_conf_t _dtrace_conf = {
- 0, /* numcpus */
- 0, /* maxcpuid */
- NULL, /* cpuids */
+ 0, /* num_possible_cpus */
+ 0, /* num_online_cpus */
+ 0, /* max_cpuid */
+ NULL, /* CPU info structs */
DIF_VERSION, /* dtc_difversion */
DIF_DIR_NREGS, /* dtc_difintregs */
DIF_DTR_NREGS, /* dtc_diftupregs */
@@ -779,8 +780,9 @@ dt_vopen(int version, int flags, int *errp,
memcpy(&dtp->dt_conf, &_dtrace_conf, sizeof (_dtrace_conf));
dt_conf_init(dtp);
- dt_dprintf("detected %d CPUs online (highest cpuid %d)\n",
- dtp->dt_conf.numcpus, dtp->dt_conf.maxcpuid);
+ dt_dprintf("detected %u CPUs online (%u possible, highest cpuid %u)\n",
+ dtp->dt_conf.num_online_cpus, dtp->dt_conf.num_possible_cpus,
+ dtp->dt_conf.max_cpuid);
if (flags & DTRACE_O_LP64)
dtp->dt_conf.dtc_ctfmodel = CTF_MODEL_LP64;
@@ -1144,7 +1146,7 @@ dtrace_close(dtrace_hdl_t *dtp)
if (dtp == NULL)
return;
- dt_free(dtp, dtp->dt_conf.cpuids);
+ dt_free(dtp, dtp->dt_conf.cpus);
if (dtp->dt_procs != NULL)
dt_proc_hash_destroy(dtp);
diff --git a/libdtrace/dt_peb.c b/libdtrace/dt_peb.c
index 033d183a..0ef1c419 100644
--- a/libdtrace/dt_peb.c
+++ b/libdtrace/dt_peb.c
@@ -125,7 +125,7 @@ dt_pebs_exit(dtrace_hdl_t *dtp)
if (dtp->dt_pebset == NULL)
return;
- for (i = 0; i < dtp->dt_conf.numcpus; i++)
+ for (i = 0; i < dtp->dt_conf.num_online_cpus; i++)
dt_peb_close(&dtp->dt_pebset->pebs[i]);
dt_free(dtp, dtp->dt_pebset->pebs);
@@ -184,7 +184,8 @@ int dt_pebs_init(dtrace_hdl_t *dtp, size_t bufsize)
/*
* Allocate the per-CPU perf event buffers.
*/
- pebs = dt_calloc(dtp, dtp->dt_conf.numcpus, sizeof(struct dt_peb));
+ pebs = dt_calloc(dtp, dtp->dt_conf.num_online_cpus,
+ sizeof(struct dt_peb));
if (pebs == NULL) {
dt_free(dtp, dtp->dt_pebset);
return -ENOMEM;
@@ -198,8 +199,8 @@ int dt_pebs_init(dtrace_hdl_t *dtp, size_t bufsize)
/*
* Initialize a perf event buffer for each online CPU.
*/
- for (i = 0; i < dtp->dt_conf.numcpus; i++) {
- int cpu = dtp->dt_conf.cpuids[i];
+ for (i = 0; i < dtp->dt_conf.num_online_cpus; i++) {
+ int cpu = dtp->dt_conf.cpus[i].cpu_id;
struct epoll_event ev;
dt_peb_t *peb = &dtp->dt_pebset->pebs[i];
diff --git a/libdtrace/dt_subr.c b/libdtrace/dt_subr.c
index 3dcb92d8..39a2eefd 100644
--- a/libdtrace/dt_subr.c
+++ b/libdtrace/dt_subr.c
@@ -988,88 +988,3 @@ dt_str2kver(const char *kverstr, dt_version_t *vp)
return 0;
}
-
-void
-dt_conf_init(dtrace_hdl_t *dtp)
-{
- char buf[BUFSIZ];
- int fd, cnt, start, end, i;
- processorid_t *cpu = NULL;
- char *p, *q;
-
- fd = open("/sys/devices/system/cpu/online", O_RDONLY);
- if (fd < 0)
- goto fail;
-
- cnt = read(fd, buf, sizeof(buf));
- close(fd);
- if (cnt <= 0)
- goto fail;
-
- /* If the string ends with a newline as it should), get rid of it. */
- if (buf[cnt - 1] == '\n')
- buf[--cnt] = 0;
-
- /* Count how many CPUs are online. */
- cnt = 0;
-again:
- p = buf;
- do {
- start = (int)strtol(p, &q, 10);
- switch (*q) {
- case '-': /* range */
- p = q + 1;
- end = (int)strtol(p, &q, 10);
-
- if (cpu) {
- for (i = start; i <= end; i++)
- *cpu++ = i;
- } else
- cnt += end - start + 1;
-
- if (*q == 0) { /* end of string */
- p = q;
- break;
- }
- if (*q != ',')
- goto fail;
-
- p = q + 1;
- break;
- case 0: /* end of string */
- if (cpu)
- *cpu++ = start;
- else
- cnt++;
-
- p = q;
- break;
- case ',': /* gap */
- if (cpu)
- *cpu++ = start;
- else
- cnt++;
-
- p = q + 1;
- break;
- }
- } while (*p != 0);
-
- if (cpu == NULL) {
- dtp->dt_conf.numcpus = cnt;
- dtp->dt_conf.cpuids = dt_zalloc(dtp,
- cnt * sizeof(processorid_t));
- cpu = dtp->dt_conf.cpuids;
- goto again;
- }
-
- /* Record the highest CPU id (i.e. the last one seen). */
- dtp->dt_conf.maxcpuid = *(cpu - 1);
-
- return;
-
-fail:
- dtp->dt_conf.numcpus = 0;
- dtp->dt_conf.maxcpuid = 0;
- dtp->dt_conf.cpuids = NULL;
-}
--
2.26.0
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