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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /kernel/trace/trace_boot.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'kernel/trace/trace_boot.c')
-rw-r--r-- | kernel/trace/trace_boot.c | 358 |
1 files changed, 358 insertions, 0 deletions
diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c new file mode 100644 index 000000000..0996d5975 --- /dev/null +++ b/kernel/trace/trace_boot.c @@ -0,0 +1,358 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * trace_boot.c + * Tracing kernel boot-time + */ + +#define pr_fmt(fmt) "trace_boot: " fmt + +#include <linux/bootconfig.h> +#include <linux/cpumask.h> +#include <linux/ftrace.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/mutex.h> +#include <linux/string.h> +#include <linux/slab.h> +#include <linux/trace.h> +#include <linux/trace_events.h> + +#include "trace.h" + +#define MAX_BUF_LEN 256 + +static void __init +trace_boot_set_instance_options(struct trace_array *tr, struct xbc_node *node) +{ + struct xbc_node *anode; + const char *p; + char buf[MAX_BUF_LEN]; + unsigned long v = 0; + + /* Common ftrace options */ + xbc_node_for_each_array_value(node, "options", anode, p) { + if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf)) { + pr_err("String is too long: %s\n", p); + continue; + } + + if (trace_set_options(tr, buf) < 0) + pr_err("Failed to set option: %s\n", buf); + } + + p = xbc_node_find_value(node, "tracing_on", NULL); + if (p && *p != '\0') { + if (kstrtoul(p, 10, &v)) + pr_err("Failed to set tracing on: %s\n", p); + if (v) + tracer_tracing_on(tr); + else + tracer_tracing_off(tr); + } + + p = xbc_node_find_value(node, "trace_clock", NULL); + if (p && *p != '\0') { + if (tracing_set_clock(tr, p) < 0) + pr_err("Failed to set trace clock: %s\n", p); + } + + p = xbc_node_find_value(node, "buffer_size", NULL); + if (p && *p != '\0') { + v = memparse(p, NULL); + if (v < PAGE_SIZE) + pr_err("Buffer size is too small: %s\n", p); + if (tracing_resize_ring_buffer(tr, v, RING_BUFFER_ALL_CPUS) < 0) + pr_err("Failed to resize trace buffer to %s\n", p); + } + + p = xbc_node_find_value(node, "cpumask", NULL); + if (p && *p != '\0') { + cpumask_var_t new_mask; + + if (alloc_cpumask_var(&new_mask, GFP_KERNEL)) { + if (cpumask_parse(p, new_mask) < 0 || + tracing_set_cpumask(tr, new_mask) < 0) + pr_err("Failed to set new CPU mask %s\n", p); + free_cpumask_var(new_mask); + } + } +} + +#ifdef CONFIG_EVENT_TRACING +static void __init +trace_boot_enable_events(struct trace_array *tr, struct xbc_node *node) +{ + struct xbc_node *anode; + char buf[MAX_BUF_LEN]; + const char *p; + + xbc_node_for_each_array_value(node, "events", anode, p) { + if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf)) { + pr_err("String is too long: %s\n", p); + continue; + } + + if (ftrace_set_clr_event(tr, buf, 1) < 0) + pr_err("Failed to enable event: %s\n", p); + } +} + +#ifdef CONFIG_KPROBE_EVENTS +static int __init +trace_boot_add_kprobe_event(struct xbc_node *node, const char *event) +{ + struct dynevent_cmd cmd; + struct xbc_node *anode; + char buf[MAX_BUF_LEN]; + const char *val; + int ret = 0; + + xbc_node_for_each_array_value(node, "probes", anode, val) { + kprobe_event_cmd_init(&cmd, buf, MAX_BUF_LEN); + + ret = kprobe_event_gen_cmd_start(&cmd, event, val); + if (ret) { + pr_err("Failed to generate probe: %s\n", buf); + break; + } + + ret = kprobe_event_gen_cmd_end(&cmd); + if (ret) { + pr_err("Failed to add probe: %s\n", buf); + break; + } + } + + return ret; +} +#else +static inline int __init +trace_boot_add_kprobe_event(struct xbc_node *node, const char *event) +{ + pr_err("Kprobe event is not supported.\n"); + return -ENOTSUPP; +} +#endif + +#ifdef CONFIG_SYNTH_EVENTS +static int __init +trace_boot_add_synth_event(struct xbc_node *node, const char *event) +{ + struct dynevent_cmd cmd; + struct xbc_node *anode; + char buf[MAX_BUF_LEN]; + const char *p; + int ret; + + synth_event_cmd_init(&cmd, buf, MAX_BUF_LEN); + + ret = synth_event_gen_cmd_start(&cmd, event, NULL); + if (ret) + return ret; + + xbc_node_for_each_array_value(node, "fields", anode, p) { + ret = synth_event_add_field_str(&cmd, p); + if (ret) + return ret; + } + + ret = synth_event_gen_cmd_end(&cmd); + if (ret < 0) + pr_err("Failed to add synthetic event: %s\n", buf); + + return ret; +} +#else +static inline int __init +trace_boot_add_synth_event(struct xbc_node *node, const char *event) +{ + pr_err("Synthetic event is not supported.\n"); + return -ENOTSUPP; +} +#endif + +static void __init +trace_boot_init_one_event(struct trace_array *tr, struct xbc_node *gnode, + struct xbc_node *enode) +{ + struct trace_event_file *file; + struct xbc_node *anode; + char buf[MAX_BUF_LEN]; + const char *p, *group, *event; + + group = xbc_node_get_data(gnode); + event = xbc_node_get_data(enode); + + if (!strcmp(group, "kprobes")) + if (trace_boot_add_kprobe_event(enode, event) < 0) + return; + if (!strcmp(group, "synthetic")) + if (trace_boot_add_synth_event(enode, event) < 0) + return; + + mutex_lock(&event_mutex); + file = find_event_file(tr, group, event); + if (!file) { + pr_err("Failed to find event: %s:%s\n", group, event); + goto out; + } + + p = xbc_node_find_value(enode, "filter", NULL); + if (p && *p != '\0') { + if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf)) + pr_err("filter string is too long: %s\n", p); + else if (apply_event_filter(file, buf) < 0) + pr_err("Failed to apply filter: %s\n", buf); + } + + if (IS_ENABLED(CONFIG_HIST_TRIGGERS)) { + xbc_node_for_each_array_value(enode, "actions", anode, p) { + if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf)) + pr_err("action string is too long: %s\n", p); + else if (trigger_process_regex(file, buf) < 0) + pr_err("Failed to apply an action: %s\n", buf); + } + } else if (xbc_node_find_value(enode, "actions", NULL)) + pr_err("Failed to apply event actions because CONFIG_HIST_TRIGGERS is not set.\n"); + + if (xbc_node_find_value(enode, "enable", NULL)) { + if (trace_event_enable_disable(file, 1, 0) < 0) + pr_err("Failed to enable event node: %s:%s\n", + group, event); + } +out: + mutex_unlock(&event_mutex); +} + +static void __init +trace_boot_init_events(struct trace_array *tr, struct xbc_node *node) +{ + struct xbc_node *gnode, *enode; + + node = xbc_node_find_child(node, "event"); + if (!node) + return; + /* per-event key starts with "event.GROUP.EVENT" */ + xbc_node_for_each_child(node, gnode) + xbc_node_for_each_child(gnode, enode) + trace_boot_init_one_event(tr, gnode, enode); +} +#else +#define trace_boot_enable_events(tr, node) do {} while (0) +#define trace_boot_init_events(tr, node) do {} while (0) +#endif + +#ifdef CONFIG_DYNAMIC_FTRACE +static void __init +trace_boot_set_ftrace_filter(struct trace_array *tr, struct xbc_node *node) +{ + struct xbc_node *anode; + const char *p; + char *q; + + xbc_node_for_each_array_value(node, "ftrace.filters", anode, p) { + q = kstrdup(p, GFP_KERNEL); + if (!q) + return; + if (ftrace_set_filter(tr->ops, q, strlen(q), 0) < 0) + pr_err("Failed to add %s to ftrace filter\n", p); + else + ftrace_filter_param = true; + kfree(q); + } + xbc_node_for_each_array_value(node, "ftrace.notraces", anode, p) { + q = kstrdup(p, GFP_KERNEL); + if (!q) + return; + if (ftrace_set_notrace(tr->ops, q, strlen(q), 0) < 0) + pr_err("Failed to add %s to ftrace filter\n", p); + else + ftrace_filter_param = true; + kfree(q); + } +} +#else +#define trace_boot_set_ftrace_filter(tr, node) do {} while (0) +#endif + +static void __init +trace_boot_enable_tracer(struct trace_array *tr, struct xbc_node *node) +{ + const char *p; + + trace_boot_set_ftrace_filter(tr, node); + + p = xbc_node_find_value(node, "tracer", NULL); + if (p && *p != '\0') { + if (tracing_set_tracer(tr, p) < 0) + pr_err("Failed to set given tracer: %s\n", p); + } + + /* Since tracer can free snapshot buffer, allocate snapshot here.*/ + if (xbc_node_find_value(node, "alloc_snapshot", NULL)) { + if (tracing_alloc_snapshot_instance(tr) < 0) + pr_err("Failed to allocate snapshot buffer\n"); + } +} + +static void __init +trace_boot_init_one_instance(struct trace_array *tr, struct xbc_node *node) +{ + trace_boot_set_instance_options(tr, node); + trace_boot_init_events(tr, node); + trace_boot_enable_events(tr, node); + trace_boot_enable_tracer(tr, node); +} + +static void __init +trace_boot_init_instances(struct xbc_node *node) +{ + struct xbc_node *inode; + struct trace_array *tr; + const char *p; + + node = xbc_node_find_child(node, "instance"); + if (!node) + return; + + xbc_node_for_each_child(node, inode) { + p = xbc_node_get_data(inode); + if (!p || *p == '\0') + continue; + + tr = trace_array_get_by_name(p); + if (!tr) { + pr_err("Failed to get trace instance %s\n", p); + continue; + } + trace_boot_init_one_instance(tr, inode); + trace_array_put(tr); + } +} + +static int __init trace_boot_init(void) +{ + struct xbc_node *trace_node; + struct trace_array *tr; + + trace_node = xbc_find_node("ftrace"); + if (!trace_node) + return 0; + + tr = top_trace_array(); + if (!tr) + return 0; + + /* Global trace array is also one instance */ + trace_boot_init_one_instance(tr, trace_node); + trace_boot_init_instances(trace_node); + + disable_tracing_selftest("running boot-time tracing"); + + return 0; +} +/* + * Start tracing at the end of core-initcall, so that it starts tracing + * from the beginning of postcore_initcall. + */ +core_initcall_sync(trace_boot_init); |