Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 31 insertions, 0 deletions

diff --git a/Documentation/accounting/cgroupstats.rst b/Documentation/accounting/cgroupstats.rst
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+==================
+Control Groupstats
+==================
+
+Control Groupstats is inspired by the discussion at
+https://lore.kernel.org/r/461CF883.2030308@sw.ru and implements per cgroup statistics as
+suggested by Andrew Morton in https://lore.kernel.org/r/20070411114927.1277d7c9.akpm@linux-foundation.org.
+
+Per cgroup statistics infrastructure re-uses code from the taskstats
+interface. A new set of cgroup operations are registered with commands
+and attributes specific to cgroups. It should be very easy to
+extend per cgroup statistics, by adding members to the cgroupstats
+structure.
+
+The current model for cgroupstats is a pull, a push model (to post
+statistics on interesting events), should be very easy to add. Currently
+user space requests for statistics by passing the cgroup path.
+Statistics about the state of all the tasks in the cgroup is returned to
+user space.
+
+NOTE: We currently rely on delay accounting for extracting information
+about tasks blocked on I/O. If CONFIG_TASK_DELAY_ACCT is disabled, this
+information will not be available.
+
+To extract cgroup statistics a utility very similar to getdelays.c
+has been developed, the sample output of the utility is shown below::
+
+  ~/balbir/cgroupstats # ./getdelays  -C "/sys/fs/cgroup/a"
+  sleeping 1, blocked 0, running 1, stopped 0, uninterruptible 0
+  ~/balbir/cgroupstats # ./getdelays  -C "/sys/fs/cgroup"
+  sleeping 155, blocked 0, running 1, stopped 0, uninterruptible 2