| Message ID | 838922de2e9756c00f4a159b2b8722ae4d28b011.1611161639.git.gitgitgadget@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | More index cleanups | expand |
On Wed, Jan 20, 2021 at 8:54 AM Derrick Stolee via GitGitGadget <gitgitgadget@gmail.com> wrote: > > From: Derrick Stolee <dstolee@microsoft.com> > > The index has an fsmonitor_dirty bitmap that records which index entries > are "dirty" based on the response from the FSMonitor. If this bitmap > ever grows larger than the index, then there was an error in how it was > constructed, and it was probably a developer's bug. > > There are several BUG() statements that are very similar, so replace > these uses with a simpler assert_index_minimum(). Since there is one > caller that uses a custom 'pos' value instead of the bit_size member, we > cannot simplify it too much. However, the error string is identical in > each, so this simplifies things. > > The end result is that the code is simpler to read while also preserving > these assertions for developers in the FSMonitor space. Indeed, looking through the patch, the end result is simpler to read. Nice cleanup. > > Signed-off-by: Derrick Stolee <dstolee@microsoft.com> > --- > fsmonitor.c | 27 +++++++++++++-------------- > 1 file changed, 13 insertions(+), 14 deletions(-) > > diff --git a/fsmonitor.c b/fsmonitor.c > index ca031c3abb8..52a50a9545a 100644 > --- a/fsmonitor.c > +++ b/fsmonitor.c > @@ -13,14 +13,19 @@ > > struct trace_key trace_fsmonitor = TRACE_KEY_INIT(FSMONITOR); > > +static void assert_index_minimum(struct index_state *istate, size_t pos) > +{ > + if (pos > istate->cache_nr) > + BUG("fsmonitor_dirty has more entries than the index (%"PRIuMAX" > %u)", > + (uintmax_t)pos, istate->cache_nr); > +} > + > static void fsmonitor_ewah_callback(size_t pos, void *is) > { > struct index_state *istate = (struct index_state *)is; > struct cache_entry *ce; > > - if (pos >= istate->cache_nr) > - BUG("fsmonitor_dirty has more entries than the index (%"PRIuMAX" >= %u)", > - (uintmax_t)pos, istate->cache_nr); > + assert_index_minimum(istate, pos); > > ce = istate->cache[pos]; > ce->ce_flags &= ~CE_FSMONITOR_VALID; > @@ -82,10 +87,8 @@ int read_fsmonitor_extension(struct index_state *istate, const void *data, > } > istate->fsmonitor_dirty = fsmonitor_dirty; > > - if (!istate->split_index && > - istate->fsmonitor_dirty->bit_size > istate->cache_nr) > - BUG("fsmonitor_dirty has more entries than the index (%"PRIuMAX" > %u)", > - (uintmax_t)istate->fsmonitor_dirty->bit_size, istate->cache_nr); > + if (!istate->split_index) > + assert_index_minimum(istate, istate->fsmonitor_dirty->bit_size); > > trace_printf_key(&trace_fsmonitor, "read fsmonitor extension successful"); > return 0; > @@ -110,10 +113,8 @@ void write_fsmonitor_extension(struct strbuf *sb, struct index_state *istate) > uint32_t ewah_size = 0; > int fixup = 0; > > - if (!istate->split_index && > - istate->fsmonitor_dirty->bit_size > istate->cache_nr) > - BUG("fsmonitor_dirty has more entries than the index (%"PRIuMAX" > %u)", > - (uintmax_t)istate->fsmonitor_dirty->bit_size, istate->cache_nr); > + if (!istate->split_index) > + assert_index_minimum(istate, istate->fsmonitor_dirty->bit_size); > > put_be32(&hdr_version, INDEX_EXTENSION_VERSION2); > strbuf_add(sb, &hdr_version, sizeof(uint32_t)); > @@ -335,9 +336,7 @@ void tweak_fsmonitor(struct index_state *istate) > } > > /* Mark all previously saved entries as dirty */ > - if (istate->fsmonitor_dirty->bit_size > istate->cache_nr) > - BUG("fsmonitor_dirty has more entries than the index (%"PRIuMAX" > %u)", > - (uintmax_t)istate->fsmonitor_dirty->bit_size, istate->cache_nr); > + assert_index_minimum(istate, istate->fsmonitor_dirty->bit_size); > ewah_each_bit(istate->fsmonitor_dirty, fsmonitor_ewah_callback, istate); > > refresh_fsmonitor(istate); > -- > gitgitgadget >
On Wed, Jan 20, 2021 at 8:58 AM Derrick Stolee via GitGitGadget <gitgitgadget@gmail.com> wrote: > > From: Derrick Stolee <dstolee@microsoft.com> > > The index has an fsmonitor_dirty bitmap that records which index entries > are "dirty" based on the response from the FSMonitor. If this bitmap > ever grows larger than the index, then there was an error in how it was > constructed, and it was probably a developer's bug. Curious: some of the tests were >=, some were > (not >=). Now that they're shared in a function they are all ">". It's pretty clear that for size-based ones, greater-than is the right test, but for position ones, isn't it still greater-or-equal? So perhaps the calls that pass an actual position should add 1... Chris
On 1/21/2021 7:53 AM, Chris Torek wrote: > On Wed, Jan 20, 2021 at 8:58 AM Derrick Stolee via GitGitGadget > <gitgitgadget@gmail.com> wrote: >> >> From: Derrick Stolee <dstolee@microsoft.com> >> >> The index has an fsmonitor_dirty bitmap that records which index entries >> are "dirty" based on the response from the FSMonitor. If this bitmap >> ever grows larger than the index, then there was an error in how it was >> constructed, and it was probably a developer's bug. > > Curious: some of the tests were >=, some were > (not >=). Now > that they're shared in a function they are all ">". > > It's pretty clear that for size-based ones, greater-than is the > right test, but for position ones, isn't it still greater-or-equal? So > perhaps the calls that pass an actual position should add 1... That's a good point. I should pass "pos + 1" in the appropriate places. Thanks, -Stolee
diff --git a/fsmonitor.c b/fsmonitor.c index ca031c3abb8..52a50a9545a 100644 --- a/fsmonitor.c +++ b/fsmonitor.c @@ -13,14 +13,19 @@ struct trace_key trace_fsmonitor = TRACE_KEY_INIT(FSMONITOR); +static void assert_index_minimum(struct index_state *istate, size_t pos) +{ + if (pos > istate->cache_nr) + BUG("fsmonitor_dirty has more entries than the index (%"PRIuMAX" > %u)", + (uintmax_t)pos, istate->cache_nr); +} + static void fsmonitor_ewah_callback(size_t pos, void *is) { struct index_state *istate = (struct index_state *)is; struct cache_entry *ce; - if (pos >= istate->cache_nr) - BUG("fsmonitor_dirty has more entries than the index (%"PRIuMAX" >= %u)", - (uintmax_t)pos, istate->cache_nr); + assert_index_minimum(istate, pos); ce = istate->cache[pos]; ce->ce_flags &= ~CE_FSMONITOR_VALID; @@ -82,10 +87,8 @@ int read_fsmonitor_extension(struct index_state *istate, const void *data, } istate->fsmonitor_dirty = fsmonitor_dirty; - if (!istate->split_index && - istate->fsmonitor_dirty->bit_size > istate->cache_nr) - BUG("fsmonitor_dirty has more entries than the index (%"PRIuMAX" > %u)", - (uintmax_t)istate->fsmonitor_dirty->bit_size, istate->cache_nr); + if (!istate->split_index) + assert_index_minimum(istate, istate->fsmonitor_dirty->bit_size); trace_printf_key(&trace_fsmonitor, "read fsmonitor extension successful"); return 0; @@ -110,10 +113,8 @@ void write_fsmonitor_extension(struct strbuf *sb, struct index_state *istate) uint32_t ewah_size = 0; int fixup = 0; - if (!istate->split_index && - istate->fsmonitor_dirty->bit_size > istate->cache_nr) - BUG("fsmonitor_dirty has more entries than the index (%"PRIuMAX" > %u)", - (uintmax_t)istate->fsmonitor_dirty->bit_size, istate->cache_nr); + if (!istate->split_index) + assert_index_minimum(istate, istate->fsmonitor_dirty->bit_size); put_be32(&hdr_version, INDEX_EXTENSION_VERSION2); strbuf_add(sb, &hdr_version, sizeof(uint32_t)); @@ -335,9 +336,7 @@ void tweak_fsmonitor(struct index_state *istate) } /* Mark all previously saved entries as dirty */ - if (istate->fsmonitor_dirty->bit_size > istate->cache_nr) - BUG("fsmonitor_dirty has more entries than the index (%"PRIuMAX" > %u)", - (uintmax_t)istate->fsmonitor_dirty->bit_size, istate->cache_nr); + assert_index_minimum(istate, istate->fsmonitor_dirty->bit_size); ewah_each_bit(istate->fsmonitor_dirty, fsmonitor_ewah_callback, istate); refresh_fsmonitor(istate);