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Slowackiego 173, 80-298 Gdansk - KRS 101882 - NIP 957-07-52-316 In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 20.03.2023 00:11, Andi Shyti wrote: > Hi Andrzej, > > looks good, few comments below, > > On Mon, Mar 06, 2023 at 05:31:58PM +0100, Andrzej Hajda wrote: >> To improve readability of ref_tracker printing following changes >> have been performed: >> - reports are printed per stack_handle - log is more compact, >> - added display name for ref_tracker_dir, >> - stack trace is printed indented, in the same printk call, >> - total number of references is printed every time, >> - print info about dropped references. > > nit: I think you can do better with the log :) > >> Signed-off-by: Andrzej Hajda >> --- >> include/linux/ref_tracker.h | 15 ++++++-- >> lib/ref_tracker.c | 90 +++++++++++++++++++++++++++++++++++++++------ >> 2 files changed, 91 insertions(+), 14 deletions(-) >> >> diff --git a/include/linux/ref_tracker.h b/include/linux/ref_tracker.h >> index 3e9e9df2a41f5f..a2cf1f6309adb2 100644 >> --- a/include/linux/ref_tracker.h >> +++ b/include/linux/ref_tracker.h >> @@ -17,12 +17,19 @@ struct ref_tracker_dir { >> bool dead; >> struct list_head list; /* List of active trackers */ >> struct list_head quarantine; /* List of dead trackers */ >> + char name[32]; >> #endif >> }; >> >> #ifdef CONFIG_REF_TRACKER >> -static inline void ref_tracker_dir_init(struct ref_tracker_dir *dir, >> - unsigned int quarantine_count) >> + >> +// Temporary allow two and three arguments, until consumers are converted > > I thought only Linus was allowed to use '//' :) > >> +#define ref_tracker_dir_init(_d, _q, args...) _ref_tracker_dir_init(_d, _q, ##args, #_d) >> +#define _ref_tracker_dir_init(_d, _q, _n, ...) __ref_tracker_dir_init(_d, _q, _n) > > [...] > >> +void __ref_tracker_dir_print(struct ref_tracker_dir *dir, >> + unsigned int display_limit) >> +{ >> + struct ref_tracker_dir_stats *stats; >> + unsigned int i = 0, skipped; >> + depot_stack_handle_t stack; >> + char *sbuf; >> + >> + lockdep_assert_held(&dir->lock); >> + >> + if (list_empty(&dir->list)) >> + return; >> + >> + stats = ref_tracker_get_stats(dir, display_limit); >> + if (IS_ERR(stats)) { >> + pr_err("%s@%pK: couldn't get stats, error %pe\n", >> + dir->name, dir, stats); >> + return; >> } >> + >> + sbuf = kmalloc(STACK_BUF_SIZE, GFP_NOWAIT | __GFP_NOWARN); >> + >> + for (i = 0, skipped = stats->total; i < stats->count; ++i) { >> + stack = stats->stacks[i].stack_handle; >> + if (sbuf && !stack_depot_snprint(stack, sbuf, STACK_BUF_SIZE, 4)) >> + sbuf[0] = 0; >> + pr_err("%s@%pK has %d/%d users at\n%s\n", dir->name, dir, >> + stats->stacks[i].count, stats->total, sbuf); > > what if sbuf is NULL? Then "(NULL)" will be printed, I suspect it will occur only on very rare occasions. > >> + skipped -= stats->stacks[i].count; >> + } >> + >> + if (skipped) > > is skipped used to double check whether stats->count is equal to > all the stacks[].conunts? What are the cases when skipped is > 0? There is display_limit parameter, so the function prints up to display_limit reports, and brief summary on remaining ones - the skipped ones. Regards Andrzej > > Andi > >> + pr_err("%s@%pK skipped reports about %d/%d users.\n", >> + dir->name, dir, skipped, stats->total); >> + >> + kfree(sbuf); >> + >> + kfree(stats); >> } >> EXPORT_SYMBOL(__ref_tracker_dir_print); >> >> >> -- >> 2.34.1