Merge branch 'kb/perf-trace'

* kb/perf-trace:
  api-trace.txt: add trace API documentation
  progress: simplify performance measurement by using getnanotime()
  wt-status: simplify performance measurement by using getnanotime()
  git: add performance tracing for git's main() function to debug scripts
  trace: add trace_performance facility to debug performance issues
  trace: add high resolution timer function to debug performance issues
  trace: add 'file:line' to all trace output
  trace: move code around, in preparation to file:line output
  trace: add current timestamp to all trace output
  trace: disable additional trace output for unit tests
  trace: add infrastructure to augment trace output with additional info
  sha1_file: change GIT_TRACE_PACK_ACCESS logging to use trace API
  Documentation/git.txt: improve documentation of 'GIT_TRACE*' variables
  trace: improve trace performance
  trace: remove redundant printf format attribute
  trace: consistently name the format parameter
  trace: move trace declarations from cache.h to new trace.h

1 files changed, 4 insertions, 26 deletions

diff --git a/sha1_file.c b/sha1_file.c
index ea61508..3f70b1d 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -36,9 +36,6 @@ static inline uintmax_t sz_fmt(size_t s) { return s; }
 
 const unsigned char null_sha1[20];
 
-static const char *no_log_pack_access = "no_log_pack_access";
-static const char *log_pack_access;
-
 /*
  * This is meant to hold a *small* number of objects that you would
  * want read_sha1_file() to be able to return, but yet you do not want
@@ -2086,27 +2083,9 @@ static void *read_object(const unsigned char *sha1, enum object_type *type,
 
 static void write_pack_access_log(struct packed_git *p, off_t obj_offset)
 {
-	static FILE *log_file;
-
-	if (!log_pack_access)
-		log_pack_access = getenv("GIT_TRACE_PACK_ACCESS");
-	if (!log_pack_access)
-		log_pack_access = no_log_pack_access;
-	if (log_pack_access == no_log_pack_access)
-		return;
-
-	if (!log_file) {
-		log_file = fopen(log_pack_access, "w");
-		if (!log_file) {
-			error("cannot open pack access log '%s' for writing: %s",
-			      log_pack_access, strerror(errno));
-			log_pack_access = no_log_pack_access;
-			return;
-		}
-	}
-	fprintf(log_file, "%s %"PRIuMAX"\n",
-		p->pack_name, (uintmax_t)obj_offset);
-	fflush(log_file);
+	static struct trace_key pack_access = TRACE_KEY_INIT(PACK_ACCESS);
+	trace_printf_key(&pack_access, "%s %"PRIuMAX"\n",
+			 p->pack_name, (uintmax_t)obj_offset);
 }
 
 int do_check_packed_object_crc;
@@ -2131,8 +2110,7 @@ void *unpack_entry(struct packed_git *p, off_t obj_offset,
 	int delta_stack_nr = 0, delta_stack_alloc = UNPACK_ENTRY_STACK_PREALLOC;
 	int base_from_cache = 0;
 
-	if (log_pack_access != no_log_pack_access)
-		write_pack_access_log(p, obj_offset);
+	write_pack_access_log(p, obj_offset);
 
 	/* PHASE 1: drill down to the innermost base object */
 	for (;;) {