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authorLinus Torvalds <torvalds@linux-foundation.org>2016-12-12 07:54:15 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2016-12-12 07:54:15 -0800
commitce38aa9cbed3d109355b0169b520362c409c0541 (patch)
tree621511c34edd22ac30ca12f78f0d478245b4ccd7 /samples/bpf/cgroup_helpers.c
parent69973b830859bc6529a7a0468ba0d80ee5117826 (diff)
parentd84701ecbcd6ad63faa7a9c18ad670d1c4d561c0 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller: 1) Platform regulatory domain support for ath10k, from Bartosz Markowski. 2) Centralize min/max MTU checking, thus removing tons of duplicated code all of the the various drivers. From Jarod Wilson. 3) Support ingress actions in act_mirred, from Shmulik Ladkani. 4) Improve device adjacency tracking, from David Ahern. 5) Add support for LED triggers on PHY link state changes, from Zach Brown. 6) Improve UDP socket memory accounting, from Paolo Abeni. 7) Set SK_MEM_QUANTUM to a fixed size of 4096, instead of PAGE_SIZE. From Eric Dumazet. 8) Collapse TCP SKBs at retransmit time even if the right side SKB has frags. Also from Eric Dumazet. 9) Add IP_RECVFRAGSIZE and IPV6_RECVFRAGSIZE cmsgs, from Willem de Bruijn. 10) Support routing by UID, from Lorenzo Colitti. 11) Handle L3 domain binding (ie. VRF) for RAW sockets, from David Ahern. 12) tcp_get_info() can run lockless, from Eric Dumazet. 13) 4-tuple UDP hashing in SFC driver, from Edward Cree. 14) Avoid reorders in GRO code, from Eric Dumazet. 15) IPV6 Segment Routing support, from David Lebrun. 16) Support MPLS push and pop for L3 packets in openvswitch, from Jiri Benc. 17) Add LRU datastructure support for BPF, Martin KaFai Lau. 18) VF support in liquidio driver, from Raghu Vatsavayi. 19) Multiqueue support in alx driver, from Tobias Regnery. 20) Networking cgroup BPF support, from Daniel Mack. 21) TCP chronograph measurements, from Francis Yan. 22) XDP support for qed driver, from Yuval Mintz. 23) BPF based lwtunnels, from Thomas Graf. 24) Consistent FIB dumping to offloading drivers, from Ido Schimmel. 25) Many optimizations for UDP under high load, from Eric Dumazet. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1522 commits) netfilter: nft_counter: rework atomic dump and reset e1000: use disable_hardirq() for e1000_netpoll() i40e: don't truncate match_method assignment net: ethernet: ti: netcp: add support of cpts net: phy: phy drivers should not set SUPPORTED_[Asym_]Pause net: l2tp: ppp: change PPPOL2TP_MSG_* => L2TP_MSG_* net: l2tp: deprecate PPPOL2TP_MSG_* in favour of L2TP_MSG_* net: l2tp: export debug flags to UAPI net: ethernet: stmmac: remove private tx queue lock net: ethernet: sxgbe: remove private tx queue lock net: bridge: shorten ageing time on topology change net: bridge: add helper to set topology change net: bridge: add helper to offload ageing time net: nicvf: use new api ethtool_{get|set}_link_ksettings net: ethernet: ti: cpsw: sync rates for channels in dual emac mode net: ethernet: ti: cpsw: re-split res only when speed is changed net: ethernet: ti: cpsw: combine budget and weight split and check net: ethernet: ti: cpsw: don't start queue twice net: ethernet: ti: cpsw: use same macros to get active slave net: mvneta: select GENERIC_ALLOCATOR ...
Diffstat (limited to 'samples/bpf/cgroup_helpers.c')
-rw-r--r--samples/bpf/cgroup_helpers.c177
1 files changed, 177 insertions, 0 deletions
diff --git a/samples/bpf/cgroup_helpers.c b/samples/bpf/cgroup_helpers.c
new file mode 100644
index 000000000000..9d1be9426401
--- /dev/null
+++ b/samples/bpf/cgroup_helpers.c
@@ -0,0 +1,177 @@
+#define _GNU_SOURCE
+#include <sched.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <linux/limits.h>
+#include <stdio.h>
+#include <linux/sched.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <ftw.h>
+
+
+#include "cgroup_helpers.h"
+
+/*
+ * To avoid relying on the system setup, when setup_cgroup_env is called
+ * we create a new mount namespace, and cgroup namespace. The cgroup2
+ * root is mounted at CGROUP_MOUNT_PATH
+ *
+ * Unfortunately, most people don't have cgroupv2 enabled at this point in time.
+ * It's easier to create our own mount namespace and manage it ourselves.
+ *
+ * We assume /mnt exists.
+ */
+
+#define WALK_FD_LIMIT 16
+#define CGROUP_MOUNT_PATH "/mnt"
+#define CGROUP_WORK_DIR "/cgroup-test-work-dir"
+#define format_cgroup_path(buf, path) \
+ snprintf(buf, sizeof(buf), "%s%s%s", CGROUP_MOUNT_PATH, \
+ CGROUP_WORK_DIR, path)
+
+/**
+ * setup_cgroup_environment() - Setup the cgroup environment
+ *
+ * After calling this function, cleanup_cgroup_environment should be called
+ * once testing is complete.
+ *
+ * This function will print an error to stderr and return 1 if it is unable
+ * to setup the cgroup environment. If setup is successful, 0 is returned.
+ */
+int setup_cgroup_environment(void)
+{
+ char cgroup_workdir[PATH_MAX + 1];
+
+ format_cgroup_path(cgroup_workdir, "");
+
+ if (unshare(CLONE_NEWNS)) {
+ log_err("unshare");
+ return 1;
+ }
+
+ if (mount("none", "/", NULL, MS_REC | MS_PRIVATE, NULL)) {
+ log_err("mount fakeroot");
+ return 1;
+ }
+
+ if (mount("none", CGROUP_MOUNT_PATH, "cgroup2", 0, NULL)) {
+ log_err("mount cgroup2");
+ return 1;
+ }
+
+ /* Cleanup existing failed runs, now that the environment is setup */
+ cleanup_cgroup_environment();
+
+ if (mkdir(cgroup_workdir, 0777) && errno != EEXIST) {
+ log_err("mkdir cgroup work dir");
+ return 1;
+ }
+
+ return 0;
+}
+
+static int nftwfunc(const char *filename, const struct stat *statptr,
+ int fileflags, struct FTW *pfwt)
+{
+ if ((fileflags & FTW_D) && rmdir(filename))
+ log_err("Removing cgroup: %s", filename);
+ return 0;
+}
+
+
+static int join_cgroup_from_top(char *cgroup_path)
+{
+ char cgroup_procs_path[PATH_MAX + 1];
+ pid_t pid = getpid();
+ int fd, rc = 0;
+
+ snprintf(cgroup_procs_path, sizeof(cgroup_procs_path),
+ "%s/cgroup.procs", cgroup_path);
+
+ fd = open(cgroup_procs_path, O_WRONLY);
+ if (fd < 0) {
+ log_err("Opening Cgroup Procs: %s", cgroup_procs_path);
+ return 1;
+ }
+
+ if (dprintf(fd, "%d\n", pid) < 0) {
+ log_err("Joining Cgroup");
+ rc = 1;
+ }
+
+ close(fd);
+ return rc;
+}
+
+/**
+ * join_cgroup() - Join a cgroup
+ * @path: The cgroup path, relative to the workdir, to join
+ *
+ * This function expects a cgroup to already be created, relative to the cgroup
+ * work dir, and it joins it. For example, passing "/my-cgroup" as the path
+ * would actually put the calling process into the cgroup
+ * "/cgroup-test-work-dir/my-cgroup"
+ *
+ * On success, it returns 0, otherwise on failure it returns 1.
+ */
+int join_cgroup(char *path)
+{
+ char cgroup_path[PATH_MAX + 1];
+
+ format_cgroup_path(cgroup_path, path);
+ return join_cgroup_from_top(cgroup_path);
+}
+
+/**
+ * cleanup_cgroup_environment() - Cleanup Cgroup Testing Environment
+ *
+ * This is an idempotent function to delete all temporary cgroups that
+ * have been created during the test, including the cgroup testing work
+ * directory.
+ *
+ * At call time, it moves the calling process to the root cgroup, and then
+ * runs the deletion process. It is idempotent, and should not fail, unless
+ * a process is lingering.
+ *
+ * On failure, it will print an error to stderr, and try to continue.
+ */
+void cleanup_cgroup_environment(void)
+{
+ char cgroup_workdir[PATH_MAX + 1];
+
+ format_cgroup_path(cgroup_workdir, "");
+ join_cgroup_from_top(CGROUP_MOUNT_PATH);
+ nftw(cgroup_workdir, nftwfunc, WALK_FD_LIMIT, FTW_DEPTH | FTW_MOUNT);
+}
+
+/**
+ * create_and_get_cgroup() - Create a cgroup, relative to workdir, and get the FD
+ * @path: The cgroup path, relative to the workdir, to join
+ *
+ * This function creates a cgroup under the top level workdir and returns the
+ * file descriptor. It is idempotent.
+ *
+ * On success, it returns the file descriptor. On failure it returns 0.
+ * If there is a failure, it prints the error to stderr.
+ */
+int create_and_get_cgroup(char *path)
+{
+ char cgroup_path[PATH_MAX + 1];
+ int fd;
+
+ format_cgroup_path(cgroup_path, path);
+ if (mkdir(cgroup_path, 0777) && errno != EEXIST) {
+ log_err("mkdiring cgroup");
+ return 0;
+ }
+
+ fd = open(cgroup_path, O_RDONLY);
+ if (fd < 0) {
+ log_err("Opening Cgroup");
+ return 0;
+ }
+
+ return fd;
+}