From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Turner Subject: [PATCH v6 08/19] read-cache: add watchman 'WAMA' extension Date: Wed, 27 Apr 2016 16:04:30 -0400 Message-ID: <1461787481-877-9-git-send-email-dturner@twopensource.com> References: <1461787481-877-1-git-send-email-dturner@twopensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: David Turner To: git@vger.kernel.org, pclouds@gmail.com X-From: git-owner@vger.kernel.org Wed Apr 27 22:06:31 2016 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1avVjA-0003bG-Q5 for gcvg-git-2@plane.gmane.org; Wed, 27 Apr 2016 22:06:29 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753562AbcD0UFZ convert rfc822-to-quoted-printable (ORCPT ); Wed, 27 Apr 2016 16:05:25 -0400 Received: from mail-qk0-f170.google.com ([209.85.220.170]:34275 "EHLO mail-qk0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752605AbcD0UFT (ORCPT ); Wed, 27 Apr 2016 16:05:19 -0400 Received: by mail-qk0-f170.google.com with SMTP id r184so23559917qkc.1 for ; Wed, 27 Apr 2016 13:05:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=twopensource-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=2MbPWk431tOo+BIGlp7Gn5IrJ3OjWEPB1yZ0iw6Q+nc=; b=dspMQSFuGAdT3RreHJabX6k+UaTN1ooSnaCz1allsmK8GvO/wbeYhr18pP72/doBTv o0f8twLJAH/PTAaY7F9coB90tsG9W8Bz22Zo1Udgc9NmANpocVrtJQCvIVwwnydUbkCt 2gtFhiFRweGM0o5hjpcDPHkJMjGicJ/YtsNtyVqPw9meGKmznbKHl5S5qYa5K4vq8vLg 4q8QUYrwjVivWmiOaCemRBmVmunMm3MXoIfOZfsC08zZGwUNniKY0ZAc4upgIxehWgyB RA5CXz7YY6hAYZBHrdZy2ifowq5Yf1FeZFV2xCF66M2WPJlZY0Bnj7Jhzd7egsqKTY6s boAw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=2MbPWk431tOo+BIGlp7Gn5IrJ3OjWEPB1yZ0iw6Q+nc=; b=OCYWhySfoXJd2cDIr0QUudYe238dPA/jy3cXbQOMsb4Ou1PxSHE1vKXM/U42btVqQt 3mlCZAmz8F92SG1j+3Qd9etcfW0GLSkTtvq4csIyT62vG3bkLForTMl/3iEVWtaHiZxz EClID1gu/swNo+1tNQk9Ft9QYXOYNkbs7fGOw483GuGPLeLydsmP2MaBKNe3o30bTqO8 O0eH4wMUiJTgAFYp3D4lOkNJAaQVzbW2Ua9rgO50nknoy6WCnhlz5mbPJJB7BlFZGBbA d5UI5gIK4F9Xr0n2ZCyXzCtwbaW93l6qR+Byxcp2TKQD3zDO6Pghr5j9BG9kuXRMotav Jqfg== X-Gm-Message-State: AOPr4FWOxekgWPuPCBs8S734G1TAUYojyjvYWGZS36GK1oymEKI4XGQOAMPEiIinJNmXMg== X-Received: by 10.55.126.6 with SMTP id z6mr10690144qkc.83.1461787518529; Wed, 27 Apr 2016 13:05:18 -0700 (PDT) Received: from ubuntu.twitter.biz ([192.133.79.145]) by smtp.gmail.com with ESMTPSA id r124sm1700085qhr.48.2016.04.27.13.05.17 (version=TLSv1/SSLv3 cipher=OTHER); Wed, 27 Apr 2016 13:05:17 -0700 (PDT) X-Mailer: git-send-email 2.4.2.767.g62658d5-twtrsrc In-Reply-To: <1461787481-877-1-git-send-email-dturner@twopensource.com> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: =46rom: Nguy=E1=BB=85n Th=C3=A1i Ng=E1=BB=8Dc Duy The extension contains a bitmap, one bit for each entry in the index. If the n-th bit is zero, the n-th entry is considered unchanged, we can ce_mark_uptodate() it without refreshing. If the bit is non-zero and we found out the corresponding file is clean after refresh, we can clear the bit. In addition, there's a list of directories in the untracked-cache to invalidate (because they have new or modified entries). The 'skipping refresh' bit is not in this patch yet as we would need watchman. More details in later patches. Signed-off-by: Nguy=E1=BB=85n Th=C3=A1i Ng=E1=BB=8Dc Duy Signed-off-by: David Turner --- Documentation/technical/index-format.txt | 22 ++++++ cache.h | 4 ++ dir.h | 3 + read-cache.c | 117 +++++++++++++++++++++++= +++++++- 4 files changed, 144 insertions(+), 2 deletions(-) diff --git a/Documentation/technical/index-format.txt b/Documentation/t= echnical/index-format.txt index ade0b0c..86ed3a6 100644 --- a/Documentation/technical/index-format.txt +++ b/Documentation/technical/index-format.txt @@ -295,3 +295,25 @@ The remaining data of each directory block is grou= ped by type: in the previous ewah bitmap. =20 - One NUL. + +=3D=3D Watchman cache + + The watchman cache tracks files for which watchman has told us about + changes. The signature for this extension is { 'W', 'A', 'M', 'A' }= =2E + + The extension starts with + + - A NUL-terminated string: the watchman vector clock at the last + time we heard from watchman. + + - 32-bit bitmap size: the size of the CE_WATCHMAN_DIRTY bitmap + + - 32-bit untracked cache entry count: the number of dirty untracked + cache entries + + - An ewah bitmap, the n-th bit indicates whether the n-th index entr= y + is CE_WATCHMAN_DIRTY. + + - a list of N NUL-terminated strings. Each is a directory that shou= ld + be marked dirty in the untracked cache because watchman has told u= s + about an update to a file in it. diff --git a/cache.h b/cache.h index 0aeb994..f4f7eef 100644 --- a/cache.h +++ b/cache.h @@ -182,6 +182,8 @@ struct cache_entry { #define CE_VALID (0x8000) #define CE_STAGESHIFT 12 =20 +#define CE_WATCHMAN_DIRTY (0x0001) + /* * Range 0xFFFF0FFF in ce_flags is divided into * two parts: in-memory flags and on-disk ones. @@ -320,6 +322,7 @@ static inline unsigned int canon_mode(unsigned int = mode) #define CACHE_TREE_CHANGED (1 << 5) #define SPLIT_INDEX_ORDERED (1 << 6) #define UNTRACKED_CHANGED (1 << 7) +#define WATCHMAN_CHANGED (1 << 8) =20 struct split_index; struct untracked_cache; @@ -344,6 +347,7 @@ struct index_state { struct untracked_cache *untracked; void *mmap; size_t mmap_size; + char *last_update; }; =20 extern struct index_state the_index; diff --git a/dir.h b/dir.h index 3ec3fb0..3d540de 100644 --- a/dir.h +++ b/dir.h @@ -142,6 +142,9 @@ struct untracked_cache { int gitignore_invalidated; int dir_invalidated; int dir_opened; + /* watchman invalidation data */ + unsigned int use_watchman : 1; + struct string_list invalid_untracked; }; =20 struct dir_struct { diff --git a/read-cache.c b/read-cache.c index 9eedf03..512f9f0 100644 --- a/read-cache.c +++ b/read-cache.c @@ -20,6 +20,7 @@ #include "utf8.h" #include "unix-socket.h" #include "pkt-line.h" +#include "ewah/ewok.h" =20 static struct cache_entry *refresh_cache_entry(struct cache_entry *ce, unsigned int options); @@ -42,11 +43,13 @@ static struct cache_entry *refresh_cache_entry(stru= ct cache_entry *ce, #define CACHE_EXT_RESOLVE_UNDO 0x52455543 /* "REUC" */ #define CACHE_EXT_LINK 0x6c696e6b /* "link" */ #define CACHE_EXT_UNTRACKED 0x554E5452 /* "UNTR" */ +#define CACHE_EXT_WATCHMAN 0x57414D41 /* "WAMA" */ =20 /* changes that can be kept in $GIT_DIR/index (basically all extension= s) */ #define EXTMASK (RESOLVE_UNDO_CHANGED | CACHE_TREE_CHANGED | \ CE_ENTRY_ADDED | CE_ENTRY_REMOVED | CE_ENTRY_CHANGED | \ - SPLIT_INDEX_ORDERED | UNTRACKED_CHANGED) + SPLIT_INDEX_ORDERED | UNTRACKED_CHANGED | \ + WATCHMAN_CHANGED) =20 struct index_state the_index; static const char *alternate_index_output; @@ -1221,8 +1224,13 @@ int refresh_index(struct index_state *istate, un= signed int flags, continue; =20 new =3D refresh_cache_ent(istate, ce, options, &cache_errno, &change= d); - if (new =3D=3D ce) + if (new =3D=3D ce) { + if (ce->ce_flags & CE_WATCHMAN_DIRTY) { + ce->ce_flags &=3D ~CE_WATCHMAN_DIRTY; + istate->cache_changed |=3D WATCHMAN_CHANGED; + } continue; + } if (!new) { const char *fmt; =20 @@ -1366,6 +1374,94 @@ static int verify_hdr(const struct cache_header = *hdr, unsigned long size) return 0; } =20 +static void mark_no_watchman(size_t pos, void *data) +{ + struct index_state *istate =3D data; + assert(pos < istate->cache_nr); + istate->cache[pos]->ce_flags |=3D CE_WATCHMAN_DIRTY; +} + +static int read_watchman_ext(struct index_state *istate, const void *d= ata, + unsigned long sz) +{ + struct ewah_bitmap *bitmap; + int ret, len; + uint32_t bitmap_size; + uint32_t untracked_nr; + + if (memchr(data, 0, sz) =3D=3D NULL) + return error("invalid extension"); + + len =3D strlen(data) + 1; + memcpy(&bitmap_size, (const char *)data + len, 4); + memcpy(&untracked_nr, (const char *)data + len + 4, 4); + untracked_nr =3D ntohl(untracked_nr); + bitmap_size =3D ntohl(bitmap_size); + + bitmap =3D ewah_new(); + ret =3D ewah_read_mmap(bitmap, (const char *)data + len + 8, bitmap_s= ize); + if (ret !=3D bitmap_size) { + ewah_free(bitmap); + return error("failed to parse ewah bitmap reading watchman index ext= ension"); + } + istate->last_update =3D xstrdup(data); + ewah_each_bit(bitmap, mark_no_watchman, istate); + ewah_free(bitmap); + + /* + * TODO: update the untracked cache from the untracked data in this + * extension. + */ + return 0; +} + +static int untracked_entry_append(struct string_list_item *item, void = *sbvoid) +{ + struct strbuf *sb =3D sbvoid; + + strbuf_addstr(sb, item->string); + strbuf_addch(sb, 0); + return 0; +} + +void write_watchman_ext(struct strbuf *sb, struct index_state* istate) +{ + struct ewah_bitmap *bitmap; + int i; + int ewah_start; + int ewah_size =3D 0; + int fixup =3D 0; + + strbuf_add(sb, istate->last_update, strlen(istate->last_update) + 1); + fixup =3D sb->len; + strbuf_add(sb, &ewah_size, 4); /* we'll fix this up later */ + if (istate->untracked) { + uint32_t nr =3D istate->untracked->invalid_untracked.nr; + nr =3D htonl(nr); + strbuf_add(sb, &nr, 4); + } else { + /* zero */ + strbuf_add(sb, &ewah_size, 4); + } + + ewah_start =3D sb->len; + bitmap =3D ewah_new(); + for (i =3D 0; i < istate->cache_nr; i++) + if (istate->cache[i]->ce_flags & CE_WATCHMAN_DIRTY) + ewah_set(bitmap, i); + ewah_serialize_strbuf(bitmap, sb); + ewah_free(bitmap); + + /* fix up size field */ + ewah_size =3D sb->len - ewah_start; + ewah_size =3D htonl(ewah_size); + memcpy(sb->buf + fixup, &ewah_size, 4); + + if (istate->untracked) + for_each_string_list(&istate->untracked->invalid_untracked, + untracked_entry_append, sb); +} + static int read_index_extension(struct index_state *istate, const char *ext, void *data, unsigned long sz) { @@ -1383,6 +1479,11 @@ static int read_index_extension(struct index_sta= te *istate, case CACHE_EXT_UNTRACKED: istate->untracked =3D read_untracked_extension(data, sz); break; + + case CACHE_EXT_WATCHMAN: + read_watchman_ext(istate, data, sz); + break; + default: if (*ext < 'A' || 'Z' < *ext) return error("index uses %.4s extension, which we do not understand= ", @@ -1814,6 +1915,8 @@ int discard_index(struct index_state *istate) istate->untracked =3D NULL; istate->from_shm =3D 0; istate->to_shm =3D 0; + free(istate->last_update); + istate->last_update =3D NULL; return 0; } =20 @@ -2211,6 +2314,16 @@ static int do_write_index(struct index_state *is= tate, int newfd, if (err) return -1; } + if (!strip_extensions && istate->last_update) { + struct strbuf sb =3D STRBUF_INIT; + + write_watchman_ext(&sb, istate); + err =3D write_index_ext_header(&c, newfd, CACHE_EXT_WATCHMAN, sb.len= ) < 0 + || ce_write(&c, newfd, sb.buf, sb.len) < 0; + strbuf_release(&sb); + if (err) + return -1; + } =20 if (ce_flush(&c, newfd, istate->sha1) || fstat(newfd, &st)) return -1; --=20 2.4.2.767.g62658d5-twtrsrc