[PATCH v7 21/39] power: use C11 alignas

[Tyler Retzlaff <roretzla@linux.microsoft.com>]

The current location used for __rte_aligned(a) for alignment of types
and variables is not compatible with MSVC. There is only a single
location accepted by both toolchains.

For variables standard C11 offers alignas(a) supported by conformant
compilers i.e. both MSVC and GCC.

For types the standard offers no alignment facility that compatibly
interoperates with C and C++ but may be achieved by relocating the
placement of __rte_aligned(a) to the aforementioned location accepted
by all currently supported toolchains.

To allow alignment for both compilers do the following:

* Move __rte_aligned from the end of {struct,union} definitions to
  be between {struct,union} and tag.

  The placement between {struct,union} and the tag allows the desired
  alignment to be imparted on the type regardless of the toolchain being
  used for all of GCC, LLVM, MSVC compilers building both C and C++.

* Replace use of __rte_aligned(a) on variables/fields with alignas(a).

Signed-off-by: Tyler Retzlaff <roretzla@linux.microsoft.com>
Acked-by: Morten Brørup <mb@smartsharesystems.com>
---
 lib/power/power_acpi_cpufreq.c       | 4 ++--
 lib/power/power_amd_pstate_cpufreq.c | 4 ++--
 lib/power/power_cppc_cpufreq.c       | 4 ++--
 lib/power/power_intel_uncore.c       | 4 ++--
 lib/power/power_pstate_cpufreq.c     | 4 ++--
 lib/power/rte_power_pmd_mgmt.c       | 4 ++--
 6 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/lib/power/power_acpi_cpufreq.c b/lib/power/power_acpi_cpufreq.c
index f8d978d..81996e1 100644
--- a/lib/power/power_acpi_cpufreq.c
+++ b/lib/power/power_acpi_cpufreq.c
@@ -41,7 +41,7 @@ enum power_state {
 /**
  * Power info per lcore.
  */
-struct acpi_power_info {
+struct __rte_cache_aligned acpi_power_info {
 	unsigned int lcore_id;               /**< Logical core id */
 	uint32_t freqs[RTE_MAX_LCORE_FREQS]; /**< Frequency array */
 	uint32_t nb_freqs;                   /**< number of available freqs */
@@ -51,7 +51,7 @@ struct acpi_power_info {
 	RTE_ATOMIC(uint32_t) state;          /**< Power in use state */
 	uint16_t turbo_available;            /**< Turbo Boost available */
 	uint16_t turbo_enable;               /**< Turbo Boost enable/disable */
-} __rte_cache_aligned;
+};
 
 static struct acpi_power_info lcore_power_info[RTE_MAX_LCORE];
 
diff --git a/lib/power/power_amd_pstate_cpufreq.c b/lib/power/power_amd_pstate_cpufreq.c
index 028f844..090a0d9 100644
--- a/lib/power/power_amd_pstate_cpufreq.c
+++ b/lib/power/power_amd_pstate_cpufreq.c
@@ -45,7 +45,7 @@ enum power_state {
 /**
  * Power info per lcore.
  */
-struct amd_pstate_power_info {
+struct __rte_cache_aligned amd_pstate_power_info {
 	uint32_t lcore_id;                   /**< Logical core id */
 	RTE_ATOMIC(uint32_t) state;          /**< Power in use state */
 	FILE *f;                             /**< FD of scaling_setspeed */
@@ -58,7 +58,7 @@ struct amd_pstate_power_info {
 	uint16_t turbo_enable;               /**< Turbo Boost enable/disable */
 	uint32_t nb_freqs;                   /**< number of available freqs */
 	uint32_t freqs[RTE_MAX_LCORE_FREQS]; /**< Frequency array */
-} __rte_cache_aligned;
+};
 
 static struct amd_pstate_power_info lcore_power_info[RTE_MAX_LCORE];
 
diff --git a/lib/power/power_cppc_cpufreq.c b/lib/power/power_cppc_cpufreq.c
index 3ddf39b..32aaacb 100644
--- a/lib/power/power_cppc_cpufreq.c
+++ b/lib/power/power_cppc_cpufreq.c
@@ -49,7 +49,7 @@ enum power_state {
 /**
  * Power info per lcore.
  */
-struct cppc_power_info {
+struct __rte_cache_aligned cppc_power_info {
 	unsigned int lcore_id;               /**< Logical core id */
 	RTE_ATOMIC(uint32_t) state;          /**< Power in use state */
 	FILE *f;                             /**< FD of scaling_setspeed */
@@ -61,7 +61,7 @@ struct cppc_power_info {
 	uint16_t turbo_enable;               /**< Turbo Boost enable/disable */
 	uint32_t nb_freqs;                   /**< number of available freqs */
 	uint32_t freqs[RTE_MAX_LCORE_FREQS]; /**< Frequency array */
-} __rte_cache_aligned;
+};
 
 static struct cppc_power_info lcore_power_info[RTE_MAX_LCORE];
 
diff --git a/lib/power/power_intel_uncore.c b/lib/power/power_intel_uncore.c
index 3ce8fcc..9c152e4 100644
--- a/lib/power/power_intel_uncore.c
+++ b/lib/power/power_intel_uncore.c
@@ -29,7 +29,7 @@
 		"/sys/devices/system/cpu/intel_uncore_frequency/package_%02u_die_%02u/initial_min_freq_khz"
 
 
-struct uncore_power_info {
+struct __rte_cache_aligned uncore_power_info {
 	unsigned int die;                  /* Core die id */
 	unsigned int pkg;                  /* Package id */
 	uint32_t freqs[MAX_UNCORE_FREQS];  /* Frequency array */
@@ -41,7 +41,7 @@ struct uncore_power_info {
 	uint32_t org_max_freq;             /* Original max freq of uncore */
 	uint32_t init_max_freq;            /* System max uncore freq */
 	uint32_t init_min_freq;            /* System min uncore freq */
-} __rte_cache_aligned;
+};
 
 static struct uncore_power_info uncore_info[RTE_MAX_NUMA_NODES][MAX_NUMA_DIE];
 
diff --git a/lib/power/power_pstate_cpufreq.c b/lib/power/power_pstate_cpufreq.c
index 73138dc..2343121 100644
--- a/lib/power/power_pstate_cpufreq.c
+++ b/lib/power/power_pstate_cpufreq.c
@@ -49,7 +49,7 @@ enum power_state {
 	POWER_UNKNOWN
 };
 
-struct pstate_power_info {
+struct __rte_cache_aligned pstate_power_info {
 	unsigned int lcore_id;               /**< Logical core id */
 	uint32_t freqs[RTE_MAX_LCORE_FREQS]; /**< Frequency array */
 	uint32_t nb_freqs;                   /**< number of available freqs */
@@ -64,7 +64,7 @@ struct pstate_power_info {
 	uint16_t turbo_available;            /**< Turbo Boost available */
 	uint16_t turbo_enable;               /**< Turbo Boost enable/disable */
 	uint16_t priority_core;              /**< High Performance core */
-} __rte_cache_aligned;
+};
 
 
 static struct pstate_power_info lcore_power_info[RTE_MAX_LCORE];
diff --git a/lib/power/rte_power_pmd_mgmt.c b/lib/power/rte_power_pmd_mgmt.c
index 591fc69..b1c18a5 100644
--- a/lib/power/rte_power_pmd_mgmt.c
+++ b/lib/power/rte_power_pmd_mgmt.c
@@ -55,7 +55,7 @@ struct queue_list_entry {
 	const struct rte_eth_rxtx_callback *cb;
 };
 
-struct pmd_core_cfg {
+struct __rte_cache_aligned pmd_core_cfg {
 	TAILQ_HEAD(queue_list_head, queue_list_entry) head;
 	/**< List of queues associated with this lcore */
 	size_t n_queues;
@@ -68,7 +68,7 @@ struct pmd_core_cfg {
 	/**< Number of queues ready to enter power optimized state */
 	uint64_t sleep_target;
 	/**< Prevent a queue from triggering sleep multiple times */
-} __rte_cache_aligned;
+};
 static struct pmd_core_cfg lcore_cfgs[RTE_MAX_LCORE];
 
 static inline bool
-- 
1.8.3.1