[PATCH] cpupower: Provide offline CPU information for cpuidle-set and cpufreq-set options

[latha]

From: Brahadambal Srinivasan <latha@xxxxxxxxxxxxxxxxxx>

When a user tries to modify cpuidle or cpufreq properties on offline
CPUs, the tool returns success (exit status 0) but also does not provide
any warning message regarding offline cpus that may have been specified
but left unchanged. In case of all or a few CPUs being offline, it can be
difficult to keep track of which CPUs didn't get the new frequency or idle
state set. Silent failures are difficult to keep track of when there are a
huge number of CPUs on which the action is performed.

This patch adds an additional message if the user attempts to modify
offline cpus.

Reported-by: Pavithra R. Prakash <pavrampu@xxxxxxxxxx>
Signed-off-by: Brahadambal Srinivasan <latha@xxxxxxxxxxxxxxxxxx>
---
 tools/power/cpupower/utils/cpufreq-set.c | 24 ++++++++++++++++++++++--
 tools/power/cpupower/utils/cpuidle-set.c | 21 ++++++++++++++++++++-
 2 files changed, 42 insertions(+), 3 deletions(-)

diff --git a/tools/power/cpupower/utils/cpufreq-set.c b/tools/power/cpupower/utils/cpufreq-set.c
index 6ed82fba5aaa..87031120582a 100644
--- a/tools/power/cpupower/utils/cpufreq-set.c
+++ b/tools/power/cpupower/utils/cpufreq-set.c
@@ -195,10 +195,14 @@ int cmd_freq_set(int argc, char **argv)
 	extern int optind, opterr, optopt;
 	int ret = 0, cont = 1;
 	int double_parm = 0, related = 0, policychange = 0;
+	int str_len = 0;
 	unsigned long freq = 0;
 	char gov[20];
+	char *offline_cpus_str = NULL;
 	unsigned int cpu;
 
+	struct bitmask *offline_cpus = NULL;
+
 	struct cpufreq_policy new_pol = {
 		.min = 0,
 		.max = 0,
@@ -311,14 +315,21 @@ int cmd_freq_set(int argc, char **argv)
 		}
 	}
 
+	offline_cpus = bitmask_alloc(sysconf(_SC_NPROCESSORS_CONF));
+	str_len = sysconf(_SC_NPROCESSORS_CONF) * 5;
+	offline_cpus_str = malloc(sizeof(char) * str_len);
 
 	/* loop over CPUs */
 	for (cpu = bitmask_first(cpus_chosen);
 	     cpu <= bitmask_last(cpus_chosen); cpu++) {
 
-		if (!bitmask_isbitset(cpus_chosen, cpu) ||
-		    cpupower_is_cpu_online(cpu) != 1)
+		if (!bitmask_isbitset(cpus_chosen, cpu))
+			continue;
+
+		if (cpupower_is_cpu_online(cpu) != 1) {
+			bitmask_setbit(offline_cpus, cpu);
 			continue;
+		}
 
 		printf(_("Setting cpu: %d\n"), cpu);
 		ret = do_one_cpu(cpu, &new_pol, freq, policychange);
@@ -328,5 +339,14 @@ int cmd_freq_set(int argc, char **argv)
 		}
 	}
 
+	if (!bitmask_isallclear(offline_cpus)) {
+		bitmask_displaylist(offline_cpus_str, str_len, offline_cpus);
+		printf(_("Following CPUs are offline:\n%s\n"),
+			 offline_cpus_str);
+		printf(_("cpupower set operation was not performed on them\n"));
+	}
+	free(offline_cpus_str);
+	bitmask_free(offline_cpus);
+
 	return 0;
 }
diff --git a/tools/power/cpupower/utils/cpuidle-set.c b/tools/power/cpupower/utils/cpuidle-set.c
index 569f268f4c7f..adf6543fd3d6 100644
--- a/tools/power/cpupower/utils/cpuidle-set.c
+++ b/tools/power/cpupower/utils/cpuidle-set.c
@@ -27,9 +27,12 @@ int cmd_idle_set(int argc, char **argv)
 	extern char *optarg;
 	extern int optind, opterr, optopt;
 	int ret = 0, cont = 1, param = 0, disabled;
+	int str_len = 0;
 	unsigned long long latency = 0, state_latency;
 	unsigned int cpu = 0, idlestate = 0, idlestates = 0;
 	char *endptr;
+	char *offline_cpus_str = NULL;
+	struct bitmask *offline_cpus = NULL;
 
 	do {
 		ret = getopt_long(argc, argv, "d:e:ED:", info_opts, NULL);
@@ -99,14 +102,20 @@ int cmd_idle_set(int argc, char **argv)
 	if (bitmask_isallclear(cpus_chosen))
 		bitmask_setall(cpus_chosen);
 
+	offline_cpus = bitmask_alloc(sysconf(_SC_NPROCESSORS_CONF));
+	str_len = sysconf(_SC_NPROCESSORS_CONF) * 5;
+	offline_cpus_str = (void *)malloc(sizeof(char) * str_len);
+
 	for (cpu = bitmask_first(cpus_chosen);
 	     cpu <= bitmask_last(cpus_chosen); cpu++) {
 
 		if (!bitmask_isbitset(cpus_chosen, cpu))
 			continue;
 
-		if (cpupower_is_cpu_online(cpu) != 1)
+		if (cpupower_is_cpu_online(cpu) != 1) {
+			bitmask_setbit(offline_cpus, cpu);
 			continue;
+		}
 
 		idlestates = cpuidle_state_count(cpu);
 		if (idlestates <= 0)
@@ -181,5 +190,15 @@ int cmd_idle_set(int argc, char **argv)
 			break;
 		}
 	}
+
+	if (!bitmask_isallclear(offline_cpus)) {
+		bitmask_displaylist(offline_cpus_str, str_len, offline_cpus);
+		printf(_("Following CPUs are offline:\n%s\n"),
+			 offline_cpus_str);
+		printf(_("CPU idle operation was not performed on them\n"));
+	}
+	free(offline_cpus_str);
+	bitmask_free(offline_cpus);
+
 	return EXIT_SUCCESS;
 }
-- 
2.19.1