diff options
Diffstat (limited to 'fsmonitor.c')
| -rw-r--r-- | fsmonitor.c | 216 |
1 files changed, 167 insertions, 49 deletions
diff --git a/fsmonitor.c b/fsmonitor.c index ab9bfc60b3..292a6742b4 100644 --- a/fsmonitor.c +++ b/fsmonitor.c @@ -3,6 +3,7 @@ #include "dir.h" #include "ewah/ewok.h" #include "fsmonitor.h" +#include "fsmonitor-ipc.h" #include "run-command.h" #include "strbuf.h" @@ -148,15 +149,18 @@ void write_fsmonitor_extension(struct strbuf *sb, struct index_state *istate) /* * Call the query-fsmonitor hook passing the last update token of the saved results. */ -static int query_fsmonitor(int version, const char *last_update, struct strbuf *query_result) +static int query_fsmonitor_hook(struct repository *r, + int version, + const char *last_update, + struct strbuf *query_result) { struct child_process cp = CHILD_PROCESS_INIT; int result; - if (!core_fsmonitor) + if (fsm_settings__get_mode(r) != FSMONITOR_MODE_HOOK) return -1; - strvec_push(&cp.args, core_fsmonitor); + strvec_push(&cp.args, fsm_settings__get_hook_path(r)); strvec_pushf(&cp.args, "%d", version); strvec_pushf(&cp.args, "%s", last_update); cp.use_shell = 1; @@ -168,29 +172,15 @@ static int query_fsmonitor(int version, const char *last_update, struct strbuf * if (result) trace2_data_intmax("fsm_hook", NULL, "query/failed", result); - else { + else trace2_data_intmax("fsm_hook", NULL, "query/response-length", query_result->len); - if (fsmonitor_is_trivial_response(query_result)) - trace2_data_intmax("fsm_hook", NULL, - "query/trivial-response", 1); - } - trace2_region_leave("fsm_hook", "query", NULL); return result; } -int fsmonitor_is_trivial_response(const struct strbuf *query_result) -{ - static char trivial_response[3] = { '\0', '/', '\0' }; - - return query_result->len >= 3 && - !memcmp(trivial_response, - &query_result->buf[query_result->len - 3], 3); -} - static void fsmonitor_refresh_callback(struct index_state *istate, char *name) { int i, len = strlen(name); @@ -229,6 +219,43 @@ static void fsmonitor_refresh_callback(struct index_state *istate, char *name) untracked_cache_invalidate_path(istate, name, 0); } +/* + * The number of pathnames that we need to receive from FSMonitor + * before we force the index to be updated. + * + * Note that any pathname within the set of received paths MAY cause + * cache-entry or istate flag bits to be updated and thus cause the + * index to be updated on disk. + * + * However, the response may contain many paths (such as ignored + * paths) that will not update any flag bits. And thus not force the + * index to be updated. (This is fine and normal.) It also means + * that the token will not be updated in the FSMonitor index + * extension. So the next Git command will find the same token in the + * index, make the same token-relative request, and receive the same + * response (plus any newly changed paths). If this response is large + * (and continues to grow), performance could be impacted. + * + * For example, if the user runs a build and it writes 100K object + * files but doesn't modify any source files, the index would not need + * to be updated. The FSMonitor response (after the build and + * relative to a pre-build token) might be 5MB. Each subsequent Git + * command will receive that same 100K/5MB response until something + * causes the index to be updated. And `refresh_fsmonitor()` will + * have to iterate over those 100K paths each time. + * + * Performance could be improved if we optionally force update the + * index after a very large response and get an updated token into + * the FSMonitor index extension. This should allow subsequent + * commands to get smaller and more current responses. + * + * The value chosen here does not need to be precise. The index + * will be updated automatically the first time the user touches + * a tracked file and causes a command like `git status` to + * update an mtime to be updated and/or set a flag bit. + */ +static int fsmonitor_force_update_threshold = 100; + void refresh_fsmonitor(struct index_state *istate) { struct strbuf query_result = STRBUF_INIT; @@ -238,17 +265,62 @@ void refresh_fsmonitor(struct index_state *istate) struct strbuf last_update_token = STRBUF_INIT; char *buf; unsigned int i; + int is_trivial = 0; + struct repository *r = istate->repo ? istate->repo : the_repository; + enum fsmonitor_mode fsm_mode = fsm_settings__get_mode(r); - if (!core_fsmonitor || istate->fsmonitor_has_run_once) + if (fsm_mode <= FSMONITOR_MODE_DISABLED || + istate->fsmonitor_has_run_once) return; - hook_version = fsmonitor_hook_version(); - istate->fsmonitor_has_run_once = 1; trace_printf_key(&trace_fsmonitor, "refresh fsmonitor"); + + if (fsm_mode == FSMONITOR_MODE_IPC) { + query_success = !fsmonitor_ipc__send_query( + istate->fsmonitor_last_update ? + istate->fsmonitor_last_update : "builtin:fake", + &query_result); + if (query_success) { + /* + * The response contains a series of nul terminated + * strings. The first is the new token. + * + * Use `char *buf` as an interlude to trick the CI + * static analysis to let us use `strbuf_addstr()` + * here (and only copy the token) rather than + * `strbuf_addbuf()`. + */ + buf = query_result.buf; + strbuf_addstr(&last_update_token, buf); + bol = last_update_token.len + 1; + is_trivial = query_result.buf[bol] == '/'; + if (is_trivial) + trace2_data_intmax("fsm_client", NULL, + "query/trivial-response", 1); + } else { + /* + * The builtin daemon is not available on this + * platform -OR- we failed to get a response. + * + * Generate a fake token (rather than a V1 + * timestamp) for the index extension. (If + * they switch back to the hook API, we don't + * want ambiguous state.) + */ + strbuf_addstr(&last_update_token, "builtin:fake"); + } + + goto apply_results; + } + + assert(fsm_mode == FSMONITOR_MODE_HOOK); + + hook_version = fsmonitor_hook_version(); + /* - * This could be racy so save the date/time now and query_fsmonitor + * This could be racy so save the date/time now and query_fsmonitor_hook * should be inclusive to ensure we don't miss potential changes. */ last_update = getnanotime(); @@ -256,13 +328,14 @@ void refresh_fsmonitor(struct index_state *istate) strbuf_addf(&last_update_token, "%"PRIu64"", last_update); /* - * If we have a last update token, call query_fsmonitor for the set of + * If we have a last update token, call query_fsmonitor_hook for the set of * changes since that token, else assume everything is possibly dirty * and check it all. */ if (istate->fsmonitor_last_update) { if (hook_version == -1 || hook_version == HOOK_INTERFACE_VERSION2) { - query_success = !query_fsmonitor(HOOK_INTERFACE_VERSION2, + query_success = !query_fsmonitor_hook( + r, HOOK_INTERFACE_VERSION2, istate->fsmonitor_last_update, &query_result); if (query_success) { @@ -283,6 +356,7 @@ void refresh_fsmonitor(struct index_state *istate) query_success = 0; } else { bol = last_update_token.len + 1; + is_trivial = query_result.buf[bol] == '/'; } } else if (hook_version < 0) { hook_version = HOOK_INTERFACE_VERSION1; @@ -292,37 +366,83 @@ void refresh_fsmonitor(struct index_state *istate) } if (hook_version == HOOK_INTERFACE_VERSION1) { - query_success = !query_fsmonitor(HOOK_INTERFACE_VERSION1, + query_success = !query_fsmonitor_hook( + r, HOOK_INTERFACE_VERSION1, istate->fsmonitor_last_update, &query_result); + if (query_success) + is_trivial = query_result.buf[0] == '/'; } - trace_performance_since(last_update, "fsmonitor process '%s'", core_fsmonitor); - trace_printf_key(&trace_fsmonitor, "fsmonitor process '%s' returned %s", - core_fsmonitor, query_success ? "success" : "failure"); + if (is_trivial) + trace2_data_intmax("fsm_hook", NULL, + "query/trivial-response", 1); + + trace_performance_since(last_update, "fsmonitor process '%s'", + fsm_settings__get_hook_path(r)); + trace_printf_key(&trace_fsmonitor, + "fsmonitor process '%s' returned %s", + fsm_settings__get_hook_path(r), + query_success ? "success" : "failure"); } - /* a fsmonitor process can return '/' to indicate all entries are invalid */ - if (query_success && query_result.buf[bol] != '/') { - /* Mark all entries returned by the monitor as dirty */ +apply_results: + /* + * The response from FSMonitor (excluding the header token) is + * either: + * + * [a] a (possibly empty) list of NUL delimited relative + * pathnames of changed paths. This list can contain + * files and directories. Directories have a trailing + * slash. + * + * [b] a single '/' to indicate the provider had no + * information and that we should consider everything + * invalid. We call this a trivial response. + */ + trace2_region_enter("fsmonitor", "apply_results", istate->repo); + + if (query_success && !is_trivial) { + /* + * Mark all pathnames returned by the monitor as dirty. + * + * This updates both the cache-entries and the untracked-cache. + */ + int count = 0; + buf = query_result.buf; for (i = bol; i < query_result.len; i++) { if (buf[i] != '\0') continue; fsmonitor_refresh_callback(istate, buf + bol); bol = i + 1; + count++; } - if (bol < query_result.len) + if (bol < query_result.len) { fsmonitor_refresh_callback(istate, buf + bol); + count++; + } /* Now mark the untracked cache for fsmonitor usage */ if (istate->untracked) istate->untracked->use_fsmonitor = 1; - } else { - /* We only want to run the post index changed hook if we've actually changed entries, so keep track - * if we actually changed entries or not */ + if (count > fsmonitor_force_update_threshold) + istate->cache_changed |= FSMONITOR_CHANGED; + + trace2_data_intmax("fsmonitor", istate->repo, "apply_count", + count); + + } else { + /* + * We failed to get a response or received a trivial response, + * so invalidate everything. + * + * We only want to run the post index changed hook if + * we've actually changed entries, so keep track if we + * actually changed entries or not. + */ int is_cache_changed = 0; - /* Mark all entries invalid */ + for (i = 0; i < istate->cache_nr; i++) { if (istate->cache[i]->ce_flags & CE_FSMONITOR_VALID) { is_cache_changed = 1; @@ -330,13 +450,18 @@ void refresh_fsmonitor(struct index_state *istate) } } - /* If we're going to check every file, ensure we save the results */ + /* + * If we're going to check every file, ensure we save + * the results. + */ if (is_cache_changed) istate->cache_changed |= FSMONITOR_CHANGED; if (istate->untracked) istate->untracked->use_fsmonitor = 0; } + trace2_region_leave("fsmonitor", "apply_results", istate->repo); + strbuf_release(&query_result); /* Now that we've updated istate, save the last_update_token */ @@ -411,7 +536,8 @@ void remove_fsmonitor(struct index_state *istate) void tweak_fsmonitor(struct index_state *istate) { unsigned int i; - int fsmonitor_enabled = git_config_get_fsmonitor(); + int fsmonitor_enabled = (fsm_settings__get_mode(istate->repo) + > FSMONITOR_MODE_DISABLED); if (istate->fsmonitor_dirty) { if (fsmonitor_enabled) { @@ -431,16 +557,8 @@ void tweak_fsmonitor(struct index_state *istate) istate->fsmonitor_dirty = NULL; } - switch (fsmonitor_enabled) { - case -1: /* keep: do nothing */ - break; - case 0: /* false */ - remove_fsmonitor(istate); - break; - case 1: /* true */ + if (fsmonitor_enabled) add_fsmonitor(istate); - break; - default: /* unknown value: do nothing */ - break; - } + else + remove_fsmonitor(istate); } |