From 33052bfd8c95054aceba4ec0d23c8cda9108644b Mon Sep 17 00:00:00 2001 From: Dave Barach Date: Mon, 17 Jun 2019 12:41:19 -0400 Subject: vppinfra: optimize elog_string Add a string hash to make sure that strings in the string table are unique. This optimization has been coded piecemeal in multiple places, we should have made the underlying function do the work years ago. Ticket: VPP-1707 Type: fix Change-Id: I5010fd4926b9b80ce3a168748f6de64e333ef498 Signed-off-by: Dave Barach --- src/vppinfra/elog.c | 35 ++++++++++++++++++++++++++++++----- 1 file changed, 30 insertions(+), 5 deletions(-) (limited to 'src/vppinfra/elog.c') diff --git a/src/vppinfra/elog.c b/src/vppinfra/elog.c index 6daed96719c..19d86bb70c0 100644 --- a/src/vppinfra/elog.c +++ b/src/vppinfra/elog.c @@ -508,6 +508,7 @@ elog_init (elog_main_t * em, u32 n_events) elog_track_register (em, &em->default_track); elog_time_now (&em->init_time); + em->string_table_hash = hash_create_string (0, sizeof (uword)); } /* Returns number of events in ring and start index. */ @@ -561,16 +562,40 @@ u32 elog_string (elog_main_t * em, char *fmt, ...) { u32 offset; + uword *p; + uword len; va_list va; + elog_lock (em); + vec_reset_length (em->string_table_tmp); va_start (va, fmt); - offset = vec_len (em->string_table); - em->string_table = (char *) va_format ((u8 *) em->string_table, fmt, &va); + em->string_table_tmp = va_format (em->string_table_tmp, fmt, &va); va_end (va); - /* Null terminate string if it is not already. */ - if (vec_end (em->string_table)[-1] != 0) - vec_add1 (em->string_table, 0); + /* See if we already have this string in the string table */ + p = hash_get_mem (em->string_table_hash, em->string_table_tmp); + + /* We already have the string, so give the caller its offset */ + if (p) + { + elog_unlock (em); + return (p[0]); + } + + /* We don't, so add it. String table entries MUST be NULL terminated */ + len = vec_len (em->string_table_tmp); + ASSERT (len > 0); + if (em->string_table_tmp[len - 1] != 0) + vec_add1 (em->string_table_tmp, 0); + + offset = vec_len (em->string_table); + vec_append (em->string_table, em->string_table_tmp); + + hash_set_mem (em->string_table_hash, em->string_table_tmp, offset); + + /* We gave the key to the string table hash, so we can't reuse it! */ + em->string_table_tmp = 0; + elog_unlock (em); return offset; } -- cgit 1.2.3-korg