Re: [PATCH] perf/core: Fix cgroup event list management

Hi Namhyung,

I love your patch! Yet something to improve:

[auto build test ERROR on tip/perf/core]
[also build test ERROR on tip/master linux/master linus/master v5.16-rc4]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Namhyung-Kim/perf-core-Fix-cgroup-event-list-management/20211211-080810
base:   https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git a9f4a6e92b3b319296fb078da2615f618f6cd80c
config: hexagon-randconfig-r045-20211210 (https://download.01.org/0day-ci/archive/20211211/202112111047.pgCIWSVK-lkp@intel.com/config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 097a1cb1d5ebb3a0ec4bcaed8ba3ff6a8e33c00a)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/226bdbf0501464bc088d582c02d0495a61a68b7c
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Namhyung-Kim/perf-core-Fix-cgroup-event-list-management/20211211-080810
        git checkout 226bdbf0501464bc088d582c02d0495a61a68b7c
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash kernel/events/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <redacted>

All errors (new ones prefixed by >>):

quoted

kernel/events/core.c:2391:58: error: no member named 'nr_cgroups' in 'struct perf_event_context'

           if (!ctx->is_active && (!is_cgroup_event(event) || ctx->nr_cgroups > 1)) {
                                                              ~~~  ^
   kernel/events/core.c:2867:30: error: no member named 'nr_cgroups' in 'struct perf_event_context'
               ctx->nr_events && (ctx->nr_cgroups || !is_cgroup_event(event))) {
                                  ~~~  ^
   2 errors generated.


vim +2391 kernel/events/core.c

  2368	
  2369	/*
  2370	 * Remove the event from a task's (or a CPU's) list of events.
  2371	 *
  2372	 * If event->ctx is a cloned context, callers must make sure that
  2373	 * every task struct that event->ctx->task could possibly point to
  2374	 * remains valid.  This is OK when called from perf_release since
  2375	 * that only calls us on the top-level context, which can't be a clone.
  2376	 * When called from perf_event_exit_task, it's OK because the
  2377	 * context has been detached from its task.
  2378	 */
  2379	static void perf_remove_from_context(struct perf_event *event, unsigned long flags)
  2380	{
  2381		struct perf_event_context *ctx = event->ctx;
  2382	
  2383		lockdep_assert_held(&ctx->mutex);
  2384	
  2385		/*
  2386		 * Because of perf_event_exit_task(), perf_remove_from_context() ought
  2387		 * to work in the face of TASK_TOMBSTONE, unlike every other
  2388		 * event_function_call() user.
  2389		 */
  2390		raw_spin_lock_irq(&ctx->lock);

2391		if (!ctx->is_active && (!is_cgroup_event(event) || ctx->nr_cgroups > 1)) {

  2392			__perf_remove_from_context(event, __get_cpu_context(ctx),
  2393						   ctx, (void *)flags);
  2394			raw_spin_unlock_irq(&ctx->lock);
  2395			return;
  2396		}
  2397		raw_spin_unlock_irq(&ctx->lock);
  2398	
  2399		event_function_call(event, __perf_remove_from_context, (void *)flags);
  2400	}
  2401	

---
0-DAY CI Kernel Test Service, Intel Corporation
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