Lines Matching +full:down +full:- +full:counting

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7 as instructions executed, cachemisses suffered, or branches mis-predicted -
8 without slowing down the kernel or applications. These registers can also
9 trigger interrupts when a threshold number of events have passed - and can
15 provides "virtual" 64-bit counters, regardless of the width of the
72 is divided into 3 bit-fields:
80 machine-specific.
119 will return -EINVAL.
121 More hw_event_types are supported as well, but they are CPU-specific
152 Counters come in two flavours: counting counters and sampling
153 counters.  A "counting" counter is one that is used for counting the
173 particular counter allowing one to take the round-robin scheduling effect
195 Such (and other) events will be recorded in a ring-buffer, which is
196 available to user-space using mmap() (see below).
213 'error' state, where reads return end-of-file (i.e. read() returns 0)
225 way to request that counting of events be restricted to times when the
229 to request counting of events restricted to guest and host contexts when
235 these events are recorded in the ring-buffer (see below).
238 This too is recorded in the ring-buffer (see below).
254  cpu == -1: the counter counts on all CPUs
256 (Note: the combination of 'pid == -1' and 'cpu == -1' is not valid.)
258 A 'pid > 0' and 'cpu == -1' counter is a per task counter that counts
263 A 'pid == -1' and 'cpu == x' counter is a per CPU counter that counts
264 all events on CPU-x. Per CPU counters need CAP_PERFMON or CAP_SYS_ADMIN
271 is created first, with group_fd = -1 in the sys_perf_event_open call
274 (A single counter on its own is created with group_fd = -1 and is
286 tracking are logged into a ring-buffer. This ring-buffer is created and
289 The mmap size should be 1+2^n pages, where the first page is a meta-data page
291 as where the ring-buffer head is.
301          * Bits needed to read the hw counters in user-space.
307          *     seq = pc->lock;
310          *     if (pc->index) {
311          *       count = pmc_read(pc->index - 1);
312          *       count += pc->offset;
317          *   } while (pc->lock != seq);
319          * NOTE: for obvious reason this only works on self-monitoring
329          * User-space reading this value should issue an rmb(), on SMP capable
330          * platforms, after reading this value -- see perf_event_wakeup().
335 NOTE: the hw-counter userspace bits are arch specific and are currently only
338 The following 2^n pages are the ring-buffer which contains events of the form:
413 Future work will include a splice() interface to the ring-buffer.
432 group other than the leader only affects that counter - disabling an
433 non-leader stops that counter from counting but doesn't affect any
436 Additionally, non-inherited overflow counters can use
456 -----------------
463 	- asm/perf_event.h - a basic stub will suffice at first
464 	- support for atomic64 types (and associated helper functions)
469 Architectures that have d-cache aliassing issues, such as Sparc and ARM,