[PATCH v1 1/2] power: fix power library with --lcores

[Sivaprasad Tummala]

This commit fixes an issue in the power library
related to using lcores mapped to different
physical cores (--lcores option in EAL).

Previously, the power library incorrectly accessed
CPU sysfs attributes for power management, treating
lcore IDs as CPU IDs.
e.g. with --lcores '1 at 128', lcore_id '1' was interpreted
as CPU_id instead of '128'.

This patch corrects the cpu_id based on lcore and CPU
mappings. It also constraints power management support
for lcores mapped to multiple physical cores/threads.

When multiple lcores are mapped to the same physical core,
invoking frequency scaling APIs on any lcore will apply the
changes effectively.

Signed-off-by: Sivaprasad Tummala <sivaprasad.tummala at amd.com>
---
 lib/power/power_acpi_cpufreq.c       |  7 ++++++-
 lib/power/power_amd_pstate_cpufreq.c |  7 ++++++-
 lib/power/power_common.c             | 23 +++++++++++++++++++++++
 lib/power/power_common.h             |  2 +-
 lib/power/power_cppc_cpufreq.c       |  7 ++++++-
 lib/power/power_pstate_cpufreq.c     |  7 ++++++-
 6 files changed, 48 insertions(+), 5 deletions(-)

diff --git a/lib/power/power_acpi_cpufreq.c b/lib/power/power_acpi_cpufreq.c
index 81996e1c13..259bc8a263 100644
--- a/lib/power/power_acpi_cpufreq.c
+++ b/lib/power/power_acpi_cpufreq.c
@@ -258,7 +258,12 @@ power_acpi_cpufreq_init(unsigned int lcore_id)
 		return -1;
 	}
 
-	pi->lcore_id = lcore_id;
+	if (check_lcore_and_set_cpu(lcore_id, &pi->lcore_id) < 0) {
+		POWER_LOG(ERR,
+			"Cannot get cpu id mapped for lcore %u", lcore_id);
+		return -1;
+	}
+
 	/* Check and set the governor */
 	if (power_set_governor_userspace(pi) < 0) {
 		POWER_LOG(ERR, "Cannot set governor of lcore %u to "
diff --git a/lib/power/power_amd_pstate_cpufreq.c b/lib/power/power_amd_pstate_cpufreq.c
index 090a0d96cb..9bfb271bb7 100644
--- a/lib/power/power_amd_pstate_cpufreq.c
+++ b/lib/power/power_amd_pstate_cpufreq.c
@@ -376,7 +376,12 @@ power_amd_pstate_cpufreq_init(unsigned int lcore_id)
 		return -1;
 	}
 
-	pi->lcore_id = lcore_id;
+	if (check_lcore_and_set_cpu(lcore_id, &pi->lcore_id) < 0) {
+		POWER_LOG(ERR,
+			"Cannot get cpu id mapped for lcore %u", lcore_id);
+		return -1;
+	}
+
 	/* Check and set the governor */
 	if (power_set_governor_userspace(pi) < 0) {
 		POWER_LOG(ERR, "Cannot set governor of lcore %u to "
diff --git a/lib/power/power_common.c b/lib/power/power_common.c
index 590986d5ef..a8d5cd1c50 100644
--- a/lib/power/power_common.c
+++ b/lib/power/power_common.c
@@ -9,6 +9,7 @@
 
 #include <rte_log.h>
 #include <rte_string_fns.h>
+#include <rte_lcore.h>
 
 #include "power_common.h"
 
@@ -204,3 +205,25 @@ power_set_governor(unsigned int lcore_id, const char *new_governor,
 
 	return ret;
 }
+
+int check_lcore_and_set_cpu(uint32_t lcore_id, uint32_t *cpu_id)
+{
+	rte_cpuset_t lcore_cpus;
+	uint32_t cpu;
+
+	lcore_cpus = rte_lcore_cpuset(lcore_id);
+	if (CPU_COUNT(&lcore_cpus) != 1) {
+		POWER_LOG(ERR,
+			"Power library does not support lcore %u mapping to %u cpus",
+			lcore_id, CPU_COUNT(&lcore_cpus));
+		return -1;
+	}
+
+	for (cpu = 0; cpu < CPU_SETSIZE; cpu++) {
+		if (CPU_ISSET(cpu, &lcore_cpus))
+			break;
+	}
+	*cpu_id = cpu;
+
+	return 0;
+}
diff --git a/lib/power/power_common.h b/lib/power/power_common.h
index 83f742f42a..c5034104d0 100644
--- a/lib/power/power_common.h
+++ b/lib/power/power_common.h
@@ -31,5 +31,5 @@ int open_core_sysfs_file(FILE **f, const char *mode, const char *format, ...)
 int read_core_sysfs_u32(FILE *f, uint32_t *val);
 int read_core_sysfs_s(FILE *f, char *buf, unsigned int len);
 int write_core_sysfs_s(FILE *f, const char *str);
-
+int check_lcore_and_set_cpu(uint32_t lcore_id, uint32_t *cpu_id);
 #endif /* _POWER_COMMON_H_ */
diff --git a/lib/power/power_cppc_cpufreq.c b/lib/power/power_cppc_cpufreq.c
index 32aaacb948..0a1d723bae 100644
--- a/lib/power/power_cppc_cpufreq.c
+++ b/lib/power/power_cppc_cpufreq.c
@@ -362,7 +362,12 @@ power_cppc_cpufreq_init(unsigned int lcore_id)
 		return -1;
 	}
 
-	pi->lcore_id = lcore_id;
+	if (check_lcore_and_set_cpu(lcore_id, &pi->lcore_id) < 0) {
+		POWER_LOG(ERR,
+			"Cannot get cpu id mapped for lcore %u", lcore_id);
+		return -1;
+	}
+
 	/* Check and set the governor */
 	if (power_set_governor_userspace(pi) < 0) {
 		POWER_LOG(ERR, "Cannot set governor of lcore %u to "
diff --git a/lib/power/power_pstate_cpufreq.c b/lib/power/power_pstate_cpufreq.c
index 2343121621..116b130be2 100644
--- a/lib/power/power_pstate_cpufreq.c
+++ b/lib/power/power_pstate_cpufreq.c
@@ -564,7 +564,12 @@ power_pstate_cpufreq_init(unsigned int lcore_id)
 		return -1;
 	}
 
-	pi->lcore_id = lcore_id;
+	if (check_lcore_and_set_cpu(lcore_id, &pi->lcore_id) < 0) {
+		POWER_LOG(ERR,
+			"Cannot get cpu id mapped for lcore %u", lcore_id);
+		return -1;
+	}
+
 	/* Check and set the governor */
 	if (power_set_governor_performance(pi) < 0) {
 		POWER_LOG(ERR, "Cannot set governor of lcore %u to "
-- 
2.34.1