| Message ID | 20220421120925.330160-1-shaozhengchao@huawei.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | BPF |
| Headers | show |
| Series | [bpf-next] samples/bpf: detach xdp prog when program exits unexpectedly in xdp_rxq_info_user | expand |
On Thu, Apr 21, 2022 at 5:07 AM Zhengchao Shao <shaozhengchao@huawei.com> wrote: > > When xdp_rxq_info_user program exits unexpectedly, it doesn't detach xdp > prog of device, and other xdp prog can't be attached to the device. So > call init_exit() to detach xdp prog when program exits unexpectedly. > > Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com> > --- > samples/bpf/xdp_rxq_info_user.c | 21 +++++++++++++++------ > 1 file changed, 15 insertions(+), 6 deletions(-) > you are introducing a new compilation warning, please fix it /data/users/andriin/linux/samples/bpf/xdp_rxq_info_user.c: In function ‘options2str’: /data/users/andriin/linux/samples/bpf/xdp_rxq_info_user.c:153:1: warning: control reaches end of non-void function [-Wreturn-type] 153 | } | ^ It also would be good to instead use bpf_link-based XDP attachment that would be auto-detached automatically on process crash (bpf_link_create() FTW). Please consider also converting this sample to skeleton (and then bpf_program__attach_xdp() as high-level alternative to bpf_link_create()). > diff --git a/samples/bpf/xdp_rxq_info_user.c b/samples/bpf/xdp_rxq_info_user.c > index f2d90cba5164..6378007e085a 100644 > --- a/samples/bpf/xdp_rxq_info_user.c > +++ b/samples/bpf/xdp_rxq_info_user.c > @@ -18,7 +18,7 @@ static const char *__doc__ = " XDP RX-queue info extract example\n\n" > #include <getopt.h> > #include <net/if.h> > #include <time.h> [...]
Thank you for your reply. I will fix the compilation warning firstly, and then convert this sample to skeleton. Thank you very much. -----邮件原件----- 发件人: Andrii Nakryiko [mailto:andrii.nakryiko@gmail.com] 发送时间: 2022年4月26日 12:35 收件人: shaozhengchao <shaozhengchao@huawei.com> 抄送: bpf <bpf@vger.kernel.org>; Networking <netdev@vger.kernel.org>; open list <linux-kernel@vger.kernel.org>; Alexei Starovoitov <ast@kernel.org>; Daniel Borkmann <daniel@iogearbox.net>; David S. Miller <davem@davemloft.net>; Jakub Kicinski <kuba@kernel.org>; Jesper Dangaard Brouer <hawk@kernel.org>; john fastabend <john.fastabend@gmail.com>; Andrii Nakryiko <andrii@kernel.org>; Martin Lau <kafai@fb.com>; Song Liu <songliubraving@fb.com>; Yonghong Song <yhs@fb.com>; KP Singh <kpsingh@kernel.org>; weiyongjun (A) <weiyongjun1@huawei.com>; yuehaibing <yuehaibing@huawei.com> 主题: Re: [PATCH bpf-next] samples/bpf: detach xdp prog when program exits unexpectedly in xdp_rxq_info_user On Thu, Apr 21, 2022 at 5:07 AM Zhengchao Shao <shaozhengchao@huawei.com> wrote: > > When xdp_rxq_info_user program exits unexpectedly, it doesn't detach > xdp prog of device, and other xdp prog can't be attached to the > device. So call init_exit() to detach xdp prog when program exits unexpectedly. > > Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com> > --- > samples/bpf/xdp_rxq_info_user.c | 21 +++++++++++++++------ > 1 file changed, 15 insertions(+), 6 deletions(-) > you are introducing a new compilation warning, please fix it /data/users/andriin/linux/samples/bpf/xdp_rxq_info_user.c: In function ‘options2str’: /data/users/andriin/linux/samples/bpf/xdp_rxq_info_user.c:153:1: warning: control reaches end of non-void function [-Wreturn-type] 153 | } | ^ It also would be good to instead use bpf_link-based XDP attachment that would be auto-detached automatically on process crash (bpf_link_create() FTW). Please consider also converting this sample to skeleton (and then bpf_program__attach_xdp() as high-level alternative to bpf_link_create()). > diff --git a/samples/bpf/xdp_rxq_info_user.c > b/samples/bpf/xdp_rxq_info_user.c index f2d90cba5164..6378007e085a > 100644 > --- a/samples/bpf/xdp_rxq_info_user.c > +++ b/samples/bpf/xdp_rxq_info_user.c > @@ -18,7 +18,7 @@ static const char *__doc__ = " XDP RX-queue info extract example\n\n" > #include <getopt.h> > #include <net/if.h> > #include <time.h> [...]
diff --git a/samples/bpf/xdp_rxq_info_user.c b/samples/bpf/xdp_rxq_info_user.c index f2d90cba5164..6378007e085a 100644 --- a/samples/bpf/xdp_rxq_info_user.c +++ b/samples/bpf/xdp_rxq_info_user.c @@ -18,7 +18,7 @@ static const char *__doc__ = " XDP RX-queue info extract example\n\n" #include <getopt.h> #include <net/if.h> #include <time.h> - +#include <limits.h> #include <arpa/inet.h> #include <linux/if_link.h> @@ -44,6 +44,9 @@ static struct bpf_map *rx_queue_index_map; #define EXIT_FAIL_BPF 4 #define EXIT_FAIL_MEM 5 +#define FAIL_MEM_SIG INT_MAX +#define FAIL_STAT_SIG (INT_MAX - 1) + static const struct option long_options[] = { {"help", no_argument, NULL, 'h' }, {"dev", required_argument, NULL, 'd' }, @@ -77,6 +80,12 @@ static void int_exit(int sig) printf("program on interface changed, not removing\n"); } } + + if (sig == FAIL_MEM_SIG) + exit(EXIT_FAIL_MEM); + else if (sig == FAIL_STAT_SIG) + exit(EXIT_FAIL); + exit(EXIT_OK); } @@ -141,7 +150,7 @@ static char* options2str(enum cfg_options_flags flag) if (flag & READ_MEM) return "read"; fprintf(stderr, "ERR: Unknown config option flags"); - exit(EXIT_FAIL); + int_exit(FAIL_STAT_SIG); } static void usage(char *argv[]) @@ -174,7 +183,7 @@ static __u64 gettime(void) res = clock_gettime(CLOCK_MONOTONIC, &t); if (res < 0) { fprintf(stderr, "Error with gettimeofday! (%i)\n", res); - exit(EXIT_FAIL); + int_exit(FAIL_STAT_SIG); } return (__u64) t.tv_sec * NANOSEC_PER_SEC + t.tv_nsec; } @@ -202,7 +211,7 @@ static struct datarec *alloc_record_per_cpu(void) array = calloc(nr_cpus, sizeof(struct datarec)); if (!array) { fprintf(stderr, "Mem alloc error (nr_cpus:%u)\n", nr_cpus); - exit(EXIT_FAIL_MEM); + int_exit(FAIL_MEM_SIG); } return array; } @@ -215,7 +224,7 @@ static struct record *alloc_record_per_rxq(void) array = calloc(nr_rxqs, sizeof(struct record)); if (!array) { fprintf(stderr, "Mem alloc error (nr_rxqs:%u)\n", nr_rxqs); - exit(EXIT_FAIL_MEM); + int_exit(FAIL_MEM_SIG); } return array; } @@ -229,7 +238,7 @@ static struct stats_record *alloc_stats_record(void) rec = calloc(1, sizeof(struct stats_record)); if (!rec) { fprintf(stderr, "Mem alloc error\n"); - exit(EXIT_FAIL_MEM); + int_exit(FAIL_MEM_SIG); } rec->rxq = alloc_record_per_rxq(); for (i = 0; i < nr_rxqs; i++)
When xdp_rxq_info_user program exits unexpectedly, it doesn't detach xdp prog of device, and other xdp prog can't be attached to the device. So call init_exit() to detach xdp prog when program exits unexpectedly. Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com> --- samples/bpf/xdp_rxq_info_user.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-)