tools lib api fs tracing_path: Remove two unused MAX_PATH paths

tracing_mnt was set but never written. tracing_events_path was set and
read on errors paths, but its value is exactly tracing_path with a
"/events" appended, so we can derive the value in the error
paths. There appears to have been a missing "/" when
tracing_events_path was initialized.

Signed-off-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20230526183401.2326121-8-irogers@google.com
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ross Zwisler <zwisler@chromium.org>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-perf-users@vger.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/lib/api/fs/tracing_path.c

@@ -13,17 +13,12 @@
 
 #include "tracing_path.h"
 
-static char tracing_mnt[PATH_MAX]  = "/sys/kernel/debug";
 static char tracing_path[PATH_MAX]        = "/sys/kernel/tracing";
-static char tracing_events_path[PATH_MAX] = "/sys/kernel/tracing/events";
 
 static void __tracing_path_set(const char *tracing, const char *mountpoint)
 {
-	snprintf(tracing_mnt, sizeof(tracing_mnt), "%s", mountpoint);
 	snprintf(tracing_path, sizeof(tracing_path), "%s/%s",
 		 mountpoint, tracing);
-	snprintf(tracing_events_path, sizeof(tracing_events_path), "%s/%s%s",
-		 mountpoint, tracing, "events");
 }
 
 static const char *tracing_path_tracefs_mount(void)
@@ -149,15 +144,15 @@ int tracing_path__strerror_open_tp(int err, char *buf, size_t size,
 			/* sdt markers */
 			if (!strncmp(filename, "sdt_", 4)) {
 				snprintf(buf, size,
-					"Error:\tFile %s/%s not found.\n"
+					"Error:\tFile %s/events/%s not found.\n"
 					"Hint:\tSDT event cannot be directly recorded on.\n"
 					"\tPlease first use 'perf probe %s:%s' before recording it.\n",
-					tracing_events_path, filename, sys, name);
+					tracing_path, filename, sys, name);
 			} else {
 				snprintf(buf, size,
-					 "Error:\tFile %s/%s not found.\n"
+					 "Error:\tFile %s/events/%s not found.\n"
 					 "Hint:\tPerhaps this kernel misses some CONFIG_ setting to enable this feature?.\n",
-					 tracing_events_path, filename);
+					 tracing_path, filename);
 			}
 			break;
 		}
@@ -169,9 +164,9 @@ int tracing_path__strerror_open_tp(int err, char *buf, size_t size,
 		break;
 	case EACCES: {
 		snprintf(buf, size,
-			 "Error:\tNo permissions to read %s/%s\n"
+			 "Error:\tNo permissions to read %s/events/%s\n"
 			 "Hint:\tTry 'sudo mount -o remount,mode=755 %s'\n",
-			 tracing_events_path, filename, tracing_path_mount());
+			 tracing_path, filename, tracing_path_mount());
 	}
 		break;
 	default: