From 52a44f83fc2d64a5e74d5d685fad2fecc7b7a321 Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Fri, 29 Mar 2019 11:12:12 +0200 Subject: perf/core: Fix the address filtering fix The following recent commit: c60f83b813e5 ("perf, pt, coresight: Fix address filters for vmas with non-zero offset") changes the address filtering logic to communicate filter ranges to the PMU driver via a single address range object, instead of having the driver do the final bit of math. That change forgets to take into account kernel filters, which are not calculated the same way as DSO based filters. Fix that by passing the kernel filters the same way as file-based filters. This doesn't require any additional changes in the drivers. Reported-by: Adrian Hunter Signed-off-by: Alexander Shishkin Signed-off-by: Peter Zijlstra (Intel) Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Fixes: c60f83b813e5 ("perf, pt, coresight: Fix address filters for vmas with non-zero offset") Link: https://lkml.kernel.org/r/20190329091212.29870-1-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar --- kernel/events/core.c | 37 +++++++++++++++++++++---------------- 1 file changed, 21 insertions(+), 16 deletions(-) (limited to 'kernel/events') diff --git a/kernel/events/core.c b/kernel/events/core.c index 534e01e7bc36..dc7dead2d2cc 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -9077,26 +9077,29 @@ static void perf_event_addr_filters_apply(struct perf_event *event) if (task == TASK_TOMBSTONE) return; - if (!ifh->nr_file_filters) - return; - - mm = get_task_mm(event->ctx->task); - if (!mm) - goto restart; + if (ifh->nr_file_filters) { + mm = get_task_mm(event->ctx->task); + if (!mm) + goto restart; - down_read(&mm->mmap_sem); + down_read(&mm->mmap_sem); + } raw_spin_lock_irqsave(&ifh->lock, flags); list_for_each_entry(filter, &ifh->list, entry) { - event->addr_filter_ranges[count].start = 0; - event->addr_filter_ranges[count].size = 0; + if (filter->path.dentry) { + /* + * Adjust base offset if the filter is associated to a + * binary that needs to be mapped: + */ + event->addr_filter_ranges[count].start = 0; + event->addr_filter_ranges[count].size = 0; - /* - * Adjust base offset if the filter is associated to a binary - * that needs to be mapped: - */ - if (filter->path.dentry) perf_addr_filter_apply(filter, mm, &event->addr_filter_ranges[count]); + } else { + event->addr_filter_ranges[count].start = filter->offset; + event->addr_filter_ranges[count].size = filter->size; + } count++; } @@ -9104,9 +9107,11 @@ static void perf_event_addr_filters_apply(struct perf_event *event) event->addr_filters_gen++; raw_spin_unlock_irqrestore(&ifh->lock, flags); - up_read(&mm->mmap_sem); + if (ifh->nr_file_filters) { + up_read(&mm->mmap_sem); - mmput(mm); + mmput(mm); + } restart: perf_event_stop(event, 1); -- cgit v1.2.3-55-g7522 From 339bc4183596e1f68c2c98a03b87aa124107c317 Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Fri, 29 Mar 2019 11:13:38 +0200 Subject: perf/ring_buffer: Fix AUX record suppression The following commit: 1627314fb54a33e ("perf: Suppress AUX/OVERWRITE records") has an unintended side-effect of also suppressing all AUX records with no flags and non-zero size, so all the regular records in the full trace mode. This breaks some use cases for people. Fix this by restoring "regular" AUX records. Reported-by: Ben Gainey Tested-by: Ben Gainey Signed-off-by: Alexander Shishkin Signed-off-by: Peter Zijlstra (Intel) Cc: Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Fixes: 1627314fb54a33e ("perf: Suppress AUX/OVERWRITE records") Link: https://lkml.kernel.org/r/20190329091338.29999-1-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar --- kernel/events/ring_buffer.c | 33 +++++++++++++++------------------ 1 file changed, 15 insertions(+), 18 deletions(-) (limited to 'kernel/events') diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index 2545ac08cc77..5eedb49a65ea 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -455,24 +455,21 @@ void perf_aux_output_end(struct perf_output_handle *handle, unsigned long size) rb->aux_head += size; } - if (size || handle->aux_flags) { - /* - * Only send RECORD_AUX if we have something useful to communicate - * - * Note: the OVERWRITE records by themselves are not considered - * useful, as they don't communicate any *new* information, - * aside from the short-lived offset, that becomes history at - * the next event sched-in and therefore isn't useful. - * The userspace that needs to copy out AUX data in overwrite - * mode should know to use user_page::aux_head for the actual - * offset. So, from now on we don't output AUX records that - * have *only* OVERWRITE flag set. - */ - - if (handle->aux_flags & ~(u64)PERF_AUX_FLAG_OVERWRITE) - perf_event_aux_event(handle->event, aux_head, size, - handle->aux_flags); - } + /* + * Only send RECORD_AUX if we have something useful to communicate + * + * Note: the OVERWRITE records by themselves are not considered + * useful, as they don't communicate any *new* information, + * aside from the short-lived offset, that becomes history at + * the next event sched-in and therefore isn't useful. + * The userspace that needs to copy out AUX data in overwrite + * mode should know to use user_page::aux_head for the actual + * offset. So, from now on we don't output AUX records that + * have *only* OVERWRITE flag set. + */ + if (size || (handle->aux_flags & ~(u64)PERF_AUX_FLAG_OVERWRITE)) + perf_event_aux_event(handle->event, aux_head, size, + handle->aux_flags); rb->user_page->aux_head = rb->aux_head; if (rb_need_aux_wakeup(rb)) -- cgit v1.2.3-55-g7522