[RFC PATCH 01/19] eal: fix variable shadowing

[Bruce Richardson]

Fix a range of variable shadowing issues flagged by -Wshadow:

* In tracing code, rename local variables to remove shadowing in the
  code.  The file-level variable "trace" is kept as-is, but the shorter
  name "t" is used for function-local vars.
* In options code, rename the "args" variable to "out_args" in the
  telemetry callback, to fix shadowing issues there.
* In malloc code, remove the redefinition of aligned_end, and just use
  the already-defined local variable in the last block of code in the
  function.

Bugzilla ID: 1742
Bugzilla ID: 1743
Fixes: 29d985cad8db ("trace: implement memory allocation")
Fixes: f330b01df996 ("eal: define the parameters in argparse format")
Fixes: 4d8bdd8b56a1 ("malloc: fix ASan handling for unmapped memory")
Cc: stable at dpdk.org

Signed-off-by: Bruce Richardson <bruce.richardson at intel.com>
---
 lib/eal/common/eal_common_options.c | 12 ++--
 lib/eal/common/eal_common_trace.c   | 89 ++++++++++++++---------------
 lib/eal/common/malloc_heap.c        |  2 +-
 3 files changed, 51 insertions(+), 52 deletions(-)

diff --git a/lib/eal/common/eal_common_options.c b/lib/eal/common/eal_common_options.c
index b1fb670ea0..820725884f 100644
--- a/lib/eal/common/eal_common_options.c
+++ b/lib/eal/common/eal_common_options.c
@@ -339,21 +339,21 @@ int
 handle_eal_info_request(const char *cmd, const char *params __rte_unused,
 		struct rte_tel_data *d)
 {
-	char **args;
+	char **out_args;
 	int used = 0;
 	int i = 0;
 
 	if (strcmp(cmd, EAL_PARAM_REQ) == 0)
-		args = eal_args;
+		out_args = eal_args;
 	else
-		args = eal_app_args;
+		out_args = eal_app_args;
 
 	rte_tel_data_start_array(d, RTE_TEL_STRING_VAL);
-	if (args == NULL || args[0] == NULL)
+	if (out_args == NULL || out_args[0] == NULL)
 		return 0;
 
-	for ( ; args[i] != NULL; i++)
-		used = rte_tel_data_add_array_string(d, args[i]);
+	for ( ; out_args[i] != NULL; i++)
+		used = rte_tel_data_add_array_string(d, out_args[i]);
 	return used;
 }
 
diff --git a/lib/eal/common/eal_common_trace.c b/lib/eal/common/eal_common_trace.c
index be041c45bb..2ef5637cdd 100644
--- a/lib/eal/common/eal_common_trace.c
+++ b/lib/eal/common/eal_common_trace.c
@@ -270,33 +270,32 @@ trace_point_dump(FILE *f, struct trace_point *tp)
 static void
 trace_lcore_mem_dump(FILE *f)
 {
-	struct trace *trace = trace_obj_get();
+	struct trace *t = trace_obj_get();
 	struct __rte_trace_header *header;
 	uint32_t count;
 
-	rte_spinlock_lock(&trace->lock);
-	if (trace->nb_trace_mem_list == 0)
+	rte_spinlock_lock(&t->lock);
+	if (t->nb_trace_mem_list == 0)
 		goto out;
-	fprintf(f, "nb_trace_mem_list = %d\n", trace->nb_trace_mem_list);
+	fprintf(f, "nb_trace_mem_list = %d\n", t->nb_trace_mem_list);
 	fprintf(f, "\nTrace mem info\n--------------\n");
-	for (count = 0; count < trace->nb_trace_mem_list; count++) {
-		header = trace->lcore_meta[count].mem;
+	for (count = 0; count < t->nb_trace_mem_list; count++) {
+		header = t->lcore_meta[count].mem;
 		fprintf(f, "\tid %d, mem=%p, area=%s, lcore_id=%d, name=%s\n",
 		count, header,
-		trace_area_to_string(trace->lcore_meta[count].area),
+		trace_area_to_string(t->lcore_meta[count].area),
 		header->stream_header.lcore_id,
 		header->stream_header.thread_name);
 	}
 out:
-	rte_spinlock_unlock(&trace->lock);
+	rte_spinlock_unlock(&t->lock);
 }
 
 RTE_EXPORT_EXPERIMENTAL_SYMBOL(rte_trace_dump, 20.05)
 void
 rte_trace_dump(FILE *f)
 {
-	struct trace_point_head *tp_list = trace_list_head_get();
-	struct trace *trace = trace_obj_get();
+	struct trace *t = trace_obj_get();
 	struct trace_point *tp;
 
 	fprintf(f, "\nGlobal info\n-----------\n");
@@ -304,13 +303,13 @@ rte_trace_dump(FILE *f)
 		rte_trace_is_enabled() ? "enabled" : "disabled");
 	fprintf(f, "mode = %s\n",
 		trace_mode_to_string(rte_trace_mode_get()));
-	fprintf(f, "dir = %s\n", trace->dir);
-	fprintf(f, "buffer len = %d\n", trace->buff_len);
-	fprintf(f, "number of trace points = %d\n", trace->nb_trace_points);
+	fprintf(f, "dir = %s\n", t->dir);
+	fprintf(f, "buffer len = %d\n", t->buff_len);
+	fprintf(f, "number of trace points = %d\n", t->nb_trace_points);
 
 	trace_lcore_mem_dump(f);
 	fprintf(f, "\nTrace point info\n----------------\n");
-	STAILQ_FOREACH(tp, tp_list, next)
+	STAILQ_FOREACH(tp, trace_list_head_get(), next)
 		trace_point_dump(f, tp);
 }
 
@@ -331,7 +330,7 @@ RTE_EXPORT_EXPERIMENTAL_SYMBOL(__rte_trace_mem_per_thread_alloc, 20.05)
 void
 __rte_trace_mem_per_thread_alloc(void)
 {
-	struct trace *trace = trace_obj_get();
+	struct trace *t = trace_obj_get();
 	struct __rte_trace_header *header;
 	uint32_t count;
 
@@ -341,30 +340,30 @@ __rte_trace_mem_per_thread_alloc(void)
 	if (RTE_PER_LCORE(trace_mem))
 		return;
 
-	rte_spinlock_lock(&trace->lock);
+	rte_spinlock_lock(&t->lock);
 
-	count = trace->nb_trace_mem_list;
+	count = t->nb_trace_mem_list;
 
 	/* Allocate room for storing the thread trace mem meta */
-	trace->lcore_meta = realloc(trace->lcore_meta,
-		sizeof(trace->lcore_meta[0]) * (count + 1));
+	t->lcore_meta = realloc(t->lcore_meta,
+		sizeof(t->lcore_meta[0]) * (count + 1));
 
 	/* Provide dummy space for fast path to consume */
-	if (trace->lcore_meta == NULL) {
+	if (t->lcore_meta == NULL) {
 		trace_crit("trace mem meta memory realloc failed");
 		header = NULL;
 		goto fail;
 	}
 
 	/* First attempt from huge page */
-	header = eal_malloc_no_trace(NULL, trace_mem_sz(trace->buff_len), 8);
+	header = eal_malloc_no_trace(NULL, trace_mem_sz(t->buff_len), 8);
 	if (header) {
-		trace->lcore_meta[count].area = TRACE_AREA_HUGEPAGE;
+		t->lcore_meta[count].area = TRACE_AREA_HUGEPAGE;
 		goto found;
 	}
 
 	/* Second attempt from heap with proper alignment */
-	size_t mem_size = trace_mem_sz(trace->buff_len);
+	size_t mem_size = trace_mem_sz(t->buff_len);
 	void *aligned_ptr = NULL;
 	int ret = posix_memalign(&aligned_ptr, 8, mem_size);
 	header = (ret == 0) ? aligned_ptr : NULL;
@@ -376,14 +375,14 @@ __rte_trace_mem_per_thread_alloc(void)
 	}
 
 	/* Second attempt from heap is success */
-	trace->lcore_meta[count].area = TRACE_AREA_HEAP;
+	t->lcore_meta[count].area = TRACE_AREA_HEAP;
 
 	/* Initialize the trace header */
 found:
 	header->offset = 0;
-	header->len = trace->buff_len;
+	header->len = t->buff_len;
 	header->stream_header.magic = TRACE_CTF_MAGIC;
-	rte_uuid_copy(header->stream_header.uuid, trace->uuid);
+	rte_uuid_copy(header->stream_header.uuid, t->uuid);
 	header->stream_header.lcore_id = rte_lcore_id();
 
 	/* Store the thread name */
@@ -392,11 +391,11 @@ __rte_trace_mem_per_thread_alloc(void)
 	thread_get_name(rte_thread_self(), name,
 		__RTE_TRACE_EMIT_STRING_LEN_MAX);
 
-	trace->lcore_meta[count].mem = header;
-	trace->nb_trace_mem_list++;
+	t->lcore_meta[count].mem = header;
+	t->nb_trace_mem_list++;
 fail:
 	RTE_PER_LCORE(trace_mem) = header;
-	rte_spinlock_unlock(&trace->lock);
+	rte_spinlock_unlock(&t->lock);
 }
 
 static void
@@ -411,7 +410,7 @@ trace_mem_per_thread_free_unlocked(struct thread_mem_meta *meta)
 void
 trace_mem_per_thread_free(void)
 {
-	struct trace *trace = trace_obj_get();
+	struct trace *t = trace_obj_get();
 	struct __rte_trace_header *header;
 	uint32_t count;
 
@@ -419,37 +418,37 @@ trace_mem_per_thread_free(void)
 	if (header == NULL)
 		return;
 
-	rte_spinlock_lock(&trace->lock);
-	for (count = 0; count < trace->nb_trace_mem_list; count++) {
-		if (trace->lcore_meta[count].mem == header)
+	rte_spinlock_lock(&t->lock);
+	for (count = 0; count < t->nb_trace_mem_list; count++) {
+		if (t->lcore_meta[count].mem == header)
 			break;
 	}
-	if (count != trace->nb_trace_mem_list) {
-		struct thread_mem_meta *meta = &trace->lcore_meta[count];
+	if (count != t->nb_trace_mem_list) {
+		struct thread_mem_meta *meta = &t->lcore_meta[count];
 
 		trace_mem_per_thread_free_unlocked(meta);
-		if (count != trace->nb_trace_mem_list - 1) {
+		if (count != t->nb_trace_mem_list - 1) {
 			memmove(meta, meta + 1,
 				sizeof(*meta) *
-				 (trace->nb_trace_mem_list - count - 1));
+				 (t->nb_trace_mem_list - count - 1));
 		}
-		trace->nb_trace_mem_list--;
+		t->nb_trace_mem_list--;
 	}
-	rte_spinlock_unlock(&trace->lock);
+	rte_spinlock_unlock(&t->lock);
 }
 
 void
 trace_mem_free(void)
 {
-	struct trace *trace = trace_obj_get();
+	struct trace *t = trace_obj_get();
 	uint32_t count;
 
-	rte_spinlock_lock(&trace->lock);
-	for (count = 0; count < trace->nb_trace_mem_list; count++) {
-		trace_mem_per_thread_free_unlocked(&trace->lcore_meta[count]);
+	rte_spinlock_lock(&t->lock);
+	for (count = 0; count < t->nb_trace_mem_list; count++) {
+		trace_mem_per_thread_free_unlocked(&t->lcore_meta[count]);
 	}
-	trace->nb_trace_mem_list = 0;
-	rte_spinlock_unlock(&trace->lock);
+	t->nb_trace_mem_list = 0;
+	rte_spinlock_unlock(&t->lock);
 }
 
 RTE_EXPORT_EXPERIMENTAL_SYMBOL(__rte_trace_point_emit_field, 20.05)
diff --git a/lib/eal/common/malloc_heap.c b/lib/eal/common/malloc_heap.c
index 13a56e490e..39240c261c 100644
--- a/lib/eal/common/malloc_heap.c
+++ b/lib/eal/common/malloc_heap.c
@@ -1044,9 +1044,9 @@ malloc_heap_free(struct malloc_elem *elem)
 	/* if we unmapped some memory, we need to do additional work for ASan */
 	if (unmapped) {
 		void *asan_end = RTE_PTR_ADD(asan_ptr, asan_data_len);
-		void *aligned_end = RTE_PTR_ADD(aligned_start, aligned_len);
 		void *aligned_trailer = RTE_PTR_SUB(aligned_start,
 				MALLOC_ELEM_TRAILER_LEN);
+		aligned_end = RTE_PTR_ADD(aligned_start, aligned_len);
 
 		/*
 		 * There was a memory area that was unmapped. This memory area
-- 
2.48.1