geemili
/
drm
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

intel: Leak the userptr test bo 

In order to use userptr, the kernel tracks the owner's mm with a
mmu_notifier. Setting that is very expensive - it involves taking all
mm_locks and a stop_machine(). This tracking lives only for as long as
the client is using userptr objects - so if the client allocates then
frees a userptr in a loop, we will be executing that heavyweight setup
everytime. To ammoritize this cost, just leak the test bo and the single
backing page we use for detecting userptr.

v2: Free the object and memory when bufmgr is destroyed.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
main
Tvrtko Ursulin 2015-04-17 11:57:28 +01:00 committed by Damien Lespiau
parent 9915e68b3b
commit 30921483c7
1 changed files with 28 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

39
intel/intel_bufmgr_gem.c
View File

@ -132,6 +132,11 @@ typedef struct _drm_intel_bufmgr_gem {
unsigned int has_vebox : 1;
bool fenced_relocs;
struct {
void *ptr;
uint32_t handle;
} userptr_active;
char *aub_filename;
FILE *aub_file;
uint32_t aub_offset;
@ -943,7 +948,6 @@ has_userptr(drm_intel_bufmgr_gem *bufmgr_gem)
void *ptr;
long pgsz;
struct drm_i915_gem_userptr userptr;
struct drm_gem_close close_bo;
pgsz = sysconf(_SC_PAGESIZE);
assert(pgsz > 0);
@ -970,15 +974,15 @@ retry:
return false;
}
memclear(close_bo);
close_bo.handle = userptr.handle;
ret = drmIoctl(bufmgr_gem->fd, DRM_IOCTL_GEM_CLOSE, &close_bo);
free(ptr);
if (ret) {
fprintf(stderr, "Failed to release test userptr object! (%d) "
"i915 kernel driver may not be sane!\n", errno);
return false;
}
/* We don't release the userptr bo here as we want to keep the
* kernel mm tracking alive for our lifetime. The first time we
* create a userptr object the kernel has to install a mmu_notifer
* which is a heavyweight operation (e.g. it requires taking all
* mm_locks and stop_machine()).
*/
bufmgr_gem->userptr_active.ptr = ptr;
bufmgr_gem->userptr_active.handle = userptr.handle;
return true;
}
@ -1805,7 +1809,8 @@ static void
drm_intel_bufmgr_gem_destroy(drm_intel_bufmgr *bufmgr)
{
drm_intel_bufmgr_gem *bufmgr_gem = (drm_intel_bufmgr_gem *) bufmgr;
int i;
struct drm_gem_close close_bo;
int i, ret;
free(bufmgr_gem->exec2_objects);
free(bufmgr_gem->exec_objects);
@ -1829,6 +1834,18 @@ drm_intel_bufmgr_gem_destroy(drm_intel_bufmgr *bufmgr)
}
}
/* Release userptr bo kept hanging around for optimisation. */
if (bufmgr_gem->userptr_active.ptr) {
memclear(close_bo);
close_bo.handle = bufmgr_gem->userptr_active.handle;
ret = drmIoctl(bufmgr_gem->fd, DRM_IOCTL_GEM_CLOSE, &close_bo);
free(bufmgr_gem->userptr_active.ptr);
if (ret)
fprintf(stderr,
"Failed to release test userptr object! (%d) "
"i915 kernel driver may not be sane!\n", errno);
}
free(bufmgr);
}