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Signed-off-by: Vincent Donnefort diff --git a/kernel/trace/trace_remote.c b/kernel/trace/trace_remote.c index 204d5bef7a8c..34847463d9e4 100644 --- a/kernel/trace/trace_remote.c +++ b/kernel/trace/trace_remote.c @@ -13,6 +13,8 @@ #include #include +#include + #include "trace.h" #define TRACEFS_DIR "remotes" @@ -1170,6 +1172,126 @@ static int poll_ms_show(struct seq_file *s, void *unused) } DEFINE_TRACE_REMOTE_ATTRIBUTE(poll_ms); +static char trace_remote_cmdline[COMMAND_LINE_SIZE]; + +static int __init set_trace_remote_cmdline(char *str) +{ + trace_append_boot_param(trace_remote_cmdline, str, '\t', COMMAND_LINE_SIZE); + return 1; +} +__setup("trace_remote=", set_trace_remote_cmdline); + +static void trace_remote_apply_cmdline_opts(struct trace_remote *remote, char *cmdline) +{ + bool dmesg_on = false; + char *opt; + int ret; + + while ((opt = strsep(&cmdline, "^"))) { + if (!*opt) + continue; + + if (!strcmp(opt, "dump_on_panic")) { + remote->panic_on = true; + } else if (!strcmp(opt, "dmesg")) { + dmesg_on = true; + } else if (!strncmp(opt, "buf_size=", 9)) { + /* buf_size can only be applied if the buffer is unloaded */ + if (trace_remote_loaded(remote)) + pr_warn("Cannot apply buf_size after events are enabled\n"); + else + remote->trace_buffer_size = memparse(opt + 9, NULL); + } else if (!strncmp(opt, "poll=", 5)) { + unsigned int poll_ms; + + if (!kstrtouint(opt + 5, 10, &poll_ms) && poll_ms > 0) + remote->poll_ms = poll_ms; + else + pr_warn("Invalid trace remote poll '%s'\n", opt); + } else { + pr_warn("Unknown trace remote option '%s'\n", opt); + } + } + + if (dmesg_on) { + ret = trace_remote_enable_dmesg(remote, true); + if (ret) + pr_warn("Failed to enable trace remote dmesg (%d)\n", ret); + } +} + +static struct remote_event * +trace_remote_find_event_by_name(struct trace_remote *remote, const char *name); + +static int +trace_remote_enable_event(struct trace_remote *remote, struct remote_event *evt, bool enable); + +static void trace_remote_apply_cmdline_events(struct trace_remote *remote, char *cmdline) +{ + bool tracing_on = false; + char *token; + int ret; + + while ((token = strsep(&cmdline, ","))) { + struct remote_event *evt; + + if (!*token) + continue; + + evt = trace_remote_find_event_by_name(remote, token); + if (!evt) { + pr_warn("trace remote event '%s' not found\n", token); + continue; + } + + ret = trace_remote_enable_event(remote, evt, true); + if (ret) + pr_warn("Failed to enable trace remote event '%s' (%d)\n", token, ret); + else + tracing_on = true; + } + + if (tracing_on) { + ret = trace_remote_enable_tracing(remote); + if (ret) + pr_warn("Failed to enable trace remote tracing (%d)\n", ret); + } +} + +static void trace_remote_apply_cmdline(const char *name, struct trace_remote *remote) +{ + char *cmdline __free(kfree) = NULL; + char *events_cmdline = NULL; + char *opts_cmdline = NULL; + char *curr, *next; + + if (!trace_remote_cmdline[0]) + return; + + cmdline = kstrdup(trace_remote_cmdline, GFP_KERNEL); + if (!cmdline) + return; + + next = cmdline; + while ((curr = strsep(&next, "\t"))) { + char *token = strsep(&curr, ","); + char *rname = strsep(&token, "^"); + + if (strcmp(rname, name)) + continue; + + opts_cmdline = token; + events_cmdline = curr; + + guard(mutex)(&remote->lock); + + if (opts_cmdline) + trace_remote_apply_cmdline_opts(remote, opts_cmdline); + if (events_cmdline) + trace_remote_apply_cmdline_events(remote, events_cmdline); + } +} + static int trace_remote_init_tracefs(const char *name, struct trace_remote *remote) { struct dentry *remote_d, *percpu_d, *d; @@ -1346,6 +1468,7 @@ int trace_remote_register(const char *name, struct trace_remote_callbacks *cbs, } list_add(&remote->node, &trace_remotes); + trace_remote_apply_cmdline(name, remote); retain_and_null_ptr(remote); return 0; @@ -1829,3 +1952,15 @@ static struct remote_event *trace_remote_find_event(struct trace_remote *remote, return bsearch((const void *)(unsigned long)id, remote->events, remote->nr_events, sizeof(*remote->events), __cmp_events); } + +static struct remote_event * +trace_remote_find_event_by_name(struct trace_remote *remote, const char *name) +{ + int i; + + for (i = 0; i < remote->nr_events; i++) { + if (!strcmp(remote->events[i].name, name)) + return &remote->events[i]; + } + return NULL; +} -- 2.55.0.691.gc56d675ccc-goog