#ifndef __PERF_SESSION_H
#define __PERF_SESSION_H

#include "trace-event.h"
#include "event.h"
#include "header.h"
#include "machine.h"
#include "symbol.h"
#include "thread.h"
#include "data.h"
#include "ordered-events.h"
#include <linux/rbtree.h>
#include <linux/perf_event.h>

struct ip_callchain;
struct thread;

struct auxtrace;
struct itrace_synth_opts;

struct perf_session {
	struct perf_header	header;
	struct machines		machines;
	struct perf_evlist	*evlist;
	struct auxtrace		*auxtrace;
	struct itrace_synth_opts *itrace_synth_opts;
	struct list_head	auxtrace_index;
	struct trace_event	tevent;
	struct time_conv_event	time_conv;
	bool			repipe;
	bool			one_mmap;
	void			*one_mmap_addr;
	u64			one_mmap_offset;
	struct ordered_events	ordered_events;
	struct perf_data_file	*file;
	struct perf_tool	*tool;
};

struct perf_tool;

struct perf_session *perf_session__new(struct perf_data_file *file,
				       bool repipe, struct perf_tool *tool);
void perf_session__delete(struct perf_session *session);

void perf_event_header__bswap(struct perf_event_header *hdr);

int perf_session__peek_event(struct perf_session *session, off_t file_offset,
			     void *buf, size_t buf_sz,
			     union perf_event **event_ptr,
			     struct perf_sample *sample);

int perf_session__process_events(struct perf_session *session);

int perf_session__queue_event(struct perf_session *s, union perf_event *event,
			      struct perf_sample *sample, u64 file_offset);

void perf_tool__fill_defaults(struct perf_tool *tool);

int perf_session__resolve_callchain(struct perf_session *session,
				    struct perf_evsel *evsel,
				    struct thread *thread,
				    struct ip_callchain *chain,
				    struct symbol **parent);

bool perf_session__has_traces(struct perf_session *session, const char *msg);

void perf_event__attr_swap(struct perf_event_attr *attr);

int perf_session__create_kernel_maps(struct perf_session *session);

void perf_session__set_id_hdr_size(struct perf_session *session);

static inline
struct machine *perf_session__find_machine(struct perf_session *session, pid_t pid)
{
	return machines__find(&session->machines, pid);
}

static inline
struct machine *perf_session__findnew_machine(struct perf_session *session, pid_t pid)
{
	return machines__findnew(&session->machines, pid);
}

struct thread *perf_session__findnew(struct perf_session *session, pid_t pid);
int perf_session__register_idle_thread(struct perf_session *session);

size_t perf_session__fprintf(struct perf_session *session, FILE *fp);

size_t perf_session__fprintf_dsos(struct perf_session *session, FILE *fp);

size_t perf_session__fprintf_dsos_buildid(struct perf_session *session, FILE *fp,
					  bool (fn)(struct dso *dso, int parm), int parm);

size_t perf_session__fprintf_nr_events(struct perf_session *session, FILE *fp);

struct perf_evsel *perf_session__find_first_evtype(struct perf_session *session,
					    unsigned int type);

int perf_session__cpu_bitmap(struct perf_session *session,
			     const char *cpu_list, unsigned long *cpu_bitmap);

void perf_session__fprintf_info(struct perf_session *s, FILE *fp, bool full);

struct perf_evsel_str_handler;

int __perf_session__set_tracepoints_handlers(struct perf_session *session,
					     const struct perf_evsel_str_handler *assocs,
					     size_t nr_assocs);

#define perf_session__set_tracepoints_handlers(session, array) \
	__perf_session__set_tracepoints_handlers(session, array, ARRAY_SIZE(array))

extern volatile int session_done;

#define session_done()	ACCESS_ONCE(session_done)

int perf_session__deliver_synth_event(struct perf_session *session,
				      union perf_event *event,
				      struct perf_sample *sample);

int perf_event__process_id_index(struct perf_tool *tool,
				 union perf_event *event,
				 struct perf_session *session);

int perf_event__synthesize_id_index(struct perf_tool *tool,
				    perf_event__handler_t process,
				    struct perf_evlist *evlist,
				    struct machine *machine);

#endif /* __PERF_SESSION_H */
lude</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2017-01-29 13:50:06 -0800</td></tr>
<tr><th>committer</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2017-01-29 13:50:06 -0800</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/include/net/irda?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>39cb2c9a316e77f6dfba96c543e55b6672d5a37e</a> (<a href='/cgit.cgi/linux/net-next.git/patch/include/net/irda?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>98fe974ee4e20121253de7f61fc8d01bdb3821c1</a> /<a href='/cgit.cgi/linux/net-next.git/tree/include/net/irda?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>include/net/irda</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/include/net/irda?id=2c5d9555d6d937966d79d4c6529a5f7b9206e405'>2c5d9555d6d937966d79d4c6529a5f7b9206e405</a> (<a href='/cgit.cgi/linux/net-next.git/diff/include/net/irda?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e&amp;id2=2c5d9555d6d937966d79d4c6529a5f7b9206e405'>diff</a>)</td></tr></table>
<div class='commit-subject'>drm/i915: Check for NULL i915_vma in intel_unpin_fb_obj()</div><div class='commit-msg'>I've seen this trigger twice now, where the i915_gem_object_to_ggtt()
call in intel_unpin_fb_obj() returns NULL, resulting in an oops
immediately afterwards as the (inlined) call to i915_vma_unpin_fence()
tries to dereference it.

It seems to be some race condition where the object is going away at
shutdown time, since both times happened when shutting down the X
server.  The call chains were different:

 - VT ioctl(KDSETMODE, KD_TEXT):

    intel_cleanup_plane_fb+0x5b/0xa0 [i915]
    drm_atomic_helper_cleanup_planes+0x6f/0x90 [drm_kms_helper]
    intel_atomic_commit_tail+0x749/0xfe0 [i915]
    intel_atomic_commit+0x3cb/0x4f0 [i915]
    drm_atomic_commit+0x4b/0x50 [drm]
    restore_fbdev_mode+0x14c/0x2a0 [drm_kms_helper]
    drm_fb_helper_restore_fbdev_mode_unlocked+0x34/0x80 [drm_kms_helper]
    drm_fb_helper_set_par+0x2d/0x60 [drm_kms_helper]
    intel_fbdev_set_par+0x18/0x70 [i915]
    fb_set_var+0x236/0x460
    fbcon_blank+0x30f/0x350
    do_unblank_screen+0xd2/0x1a0
    vt_ioctl+0x507/0x12a0
    tty_ioctl+0x355/0xc30
    do_vfs_ioctl+0xa3/0x5e0
    SyS_ioctl+0x79/0x90
    entry_SYSCALL_64_fastpath+0x13/0x94

 - i915 unpin_work workqueue:

    intel_unpin_work_fn+0x58/0x140 [i915]
    process_one_work+0x1f1/0x480
    worker_thread+0x48/0x4d0
    kthread+0x101/0x140

and this patch purely papers over the issue by adding a NULL pointer
check and a WARN_ON_ONCE() to avoid the oops that would then generally
make the machine unresponsive.

Other callers of i915_gem_object_to_ggtt() seem to also check for the
returned pointer being NULL and warn about it, so this clearly has
happened before in other places.

[ Reported it originally to the i915 developers on Jan 8, applying the
  ugly workaround on my own now after triggering the problem for the
  second time with no feedback.

  This is likely to be the same bug reported as

     https://bugs.freedesktop.org/show_bug.cgi?id=98829
     https://bugs.freedesktop.org/show_bug.cgi?id=99134

  which has a patch for the underlying problem, but it hasn't gotten to
  me, so I'm applying the workaround. ]

Cc: Daniel Vetter &lt;daniel.vetter@intel.com&gt;
Cc: Jani Nikula &lt;jani.nikula@linux.intel.com&gt;
Cc: Ville Syrjälä &lt;ville.syrjala@linux.intel.com&gt;
Cc: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Cc: Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt;
Cc: Tvrtko Ursulin &lt;tvrtko.ursulin@intel.com&gt;
Cc: Imre Deak &lt;imre.deak@intel.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>Diffstat</a> (limited to 'include/net/irda')</div><table summary='diffstat' class='diffstat'>