io_uring/fdinfo.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/kernel.h>
   3 #include <linux/errno.h>
   4 #include <linux/fs.h>
   5 #include <linux/file.h>
   6 #include <linux/proc_fs.h>
   7 #include <linux/seq_file.h>
   8 #include <linux/io_uring.h>
   9
  10 #include <uapi/linux/io_uring.h>
  11
  12 #include "io_uring.h"
  13 #include "sqpoll.h"
  14 #include "fdinfo.h"
  15 #include "cancel.h"
  16 #include "rsrc.h"
  17
  18 #ifdef CONFIG_PROC_FS
  19 static __cold int io_uring_show_cred(struct seq_file *m, unsigned int id,
  20                 const struct cred *cred)
  21 {
  22         struct user_namespace *uns = seq_user_ns(m);
  23         struct group_info *gi;
  24         kernel_cap_t cap;
  25         int g;
  26
  27         seq_printf(m, "%5d\n", id);
  28         seq_put_decimal_ull(m, "\tUid:\t", from_kuid_munged(uns, cred->uid));
  29         seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->euid));
  30         seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->suid));
  31         seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->fsuid));
  32         seq_put_decimal_ull(m, "\n\tGid:\t", from_kgid_munged(uns, cred->gid));
  33         seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->egid));
  34         seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->sgid));
  35         seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->fsgid));
  36         seq_puts(m, "\n\tGroups:\t");
  37         gi = cred->group_info;
  38         for (g = 0; g < gi->ngroups; g++) {
  39                 seq_put_decimal_ull(m, g ? " " : "",
  40                                         from_kgid_munged(uns, gi->gid[g]));
  41         }
  42         seq_puts(m, "\n\tCapEff:\t");
  43         cap = cred->cap_effective;
  44         seq_put_hex_ll(m, NULL, cap.val, 16);
  45         seq_putc(m, '\n');
  46         return 0;
  47 }
  48
  49 #ifdef CONFIG_NET_RX_BUSY_POLL
  50 static __cold void common_tracking_show_fdinfo(struct io_ring_ctx *ctx,
  51                                                struct seq_file *m,
  52                                                const char *tracking_strategy)
  53 {
  54         seq_puts(m, "NAPI:\tenabled\n");
  55         seq_printf(m, "napi tracking:\t%s\n", tracking_strategy);
  56         seq_printf(m, "napi_busy_poll_dt:\t%llu\n", ctx->napi_busy_poll_dt);
  57         if (ctx->napi_prefer_busy_poll)
  58                 seq_puts(m, "napi_prefer_busy_poll:\ttrue\n");
  59         else
  60                 seq_puts(m, "napi_prefer_busy_poll:\tfalse\n");
  61 }
  62
  63 static __cold void napi_show_fdinfo(struct io_ring_ctx *ctx,
  64                                     struct seq_file *m)
  65 {
  66         unsigned int mode = READ_ONCE(ctx->napi_track_mode);
  67
  68         switch (mode) {
  69         case IO_URING_NAPI_TRACKING_INACTIVE:
  70                 seq_puts(m, "NAPI:\tdisabled\n");
  71                 break;
  72         case IO_URING_NAPI_TRACKING_DYNAMIC:
  73                 common_tracking_show_fdinfo(ctx, m, "dynamic");
  74                 break;
  75         case IO_URING_NAPI_TRACKING_STATIC:
  76                 common_tracking_show_fdinfo(ctx, m, "static");
  77                 break;
  78         default:
  79                 seq_printf(m, "NAPI:\tunknown mode (%u)\n", mode);
  80         }
  81 }
  82 #else
  83 static inline void napi_show_fdinfo(struct io_ring_ctx *ctx,
  84                                     struct seq_file *m)
  85 {
  86 }
  87 #endif
  88
  89 /*
  90  * Caller holds a reference to the file already, we don't need to do
  91  * anything else to get an extra reference.
  92  */
  93 __cold void io_uring_show_fdinfo(struct seq_file *m, struct file *file)
  94 {
  95         struct io_ring_ctx *ctx = file->private_data;
  96         struct io_overflow_cqe *ocqe;
  97         struct io_rings *r = ctx->rings;
  98         struct rusage sq_usage;
  99         unsigned int sq_mask = ctx->sq_entries - 1, cq_mask = ctx->cq_entries - 1;
 100         unsigned int sq_head = READ_ONCE(r->sq.head);
 101         unsigned int sq_tail = READ_ONCE(r->sq.tail);
 102         unsigned int cq_head = READ_ONCE(r->cq.head);
 103         unsigned int cq_tail = READ_ONCE(r->cq.tail);
 104         unsigned int cq_shift = 0;
 105         unsigned int sq_shift = 0;
 106         unsigned int sq_entries, cq_entries;
 107         int sq_pid = -1, sq_cpu = -1;
 108         u64 sq_total_time = 0, sq_work_time = 0;
 109         bool has_lock;
 110         unsigned int i;
 111
 112         if (ctx->flags & IORING_SETUP_CQE32)
 113                 cq_shift = 1;
 114         if (ctx->flags & IORING_SETUP_SQE128)
 115                 sq_shift = 1;
 116
 117         /*
 118          * we may get imprecise sqe and cqe info if uring is actively running
 119          * since we get cached_sq_head and cached_cq_tail without uring_lock
 120          * and sq_tail and cq_head are changed by userspace. But it's ok since
 121          * we usually use these info when it is stuck.
 122          */
 123         seq_printf(m, "SqMask:\t0x%x\n", sq_mask);
 124         seq_printf(m, "SqHead:\t%u\n", sq_head);
 125         seq_printf(m, "SqTail:\t%u\n", sq_tail);
 126         seq_printf(m, "CachedSqHead:\t%u\n", ctx->cached_sq_head);
 127         seq_printf(m, "CqMask:\t0x%x\n", cq_mask);
 128         seq_printf(m, "CqHead:\t%u\n", cq_head);
 129         seq_printf(m, "CqTail:\t%u\n", cq_tail);
 130         seq_printf(m, "CachedCqTail:\t%u\n", ctx->cached_cq_tail);
 131         seq_printf(m, "SQEs:\t%u\n", sq_tail - sq_head);
 132         sq_entries = min(sq_tail - sq_head, ctx->sq_entries);
 133         for (i = 0; i < sq_entries; i++) {
 134                 unsigned int entry = i + sq_head;
 135                 struct io_uring_sqe *sqe;
 136                 unsigned int sq_idx;
 137
 138                 if (ctx->flags & IORING_SETUP_NO_SQARRAY)
 139                         break;
 140                 sq_idx = READ_ONCE(ctx->sq_array[entry & sq_mask]);
 141                 if (sq_idx > sq_mask)
 142                         continue;
 143                 sqe = &ctx->sq_sqes[sq_idx << sq_shift];
 144                 seq_printf(m, "%5u: opcode:%s, fd:%d, flags:%x, off:%llu, "
 145                               "addr:0x%llx, rw_flags:0x%x, buf_index:%d "
 146                               "user_data:%llu",
 147                            sq_idx, io_uring_get_opcode(sqe->opcode), sqe->fd,
 148                            sqe->flags, (unsigned long long) sqe->off,
 149                            (unsigned long long) sqe->addr, sqe->rw_flags,
 150                            sqe->buf_index, sqe->user_data);
 151                 if (sq_shift) {
 152                         u64 *sqeb = (void *) (sqe + 1);
 153                         int size = sizeof(struct io_uring_sqe) / sizeof(u64);
 154                         int j;
 155
 156                         for (j = 0; j < size; j++) {
 157                                 seq_printf(m, ", e%d:0x%llx", j,
 158                                                 (unsigned long long) *sqeb);
 159                                 sqeb++;
 160                         }
 161                 }
 162                 seq_printf(m, "\n");
 163         }
 164         seq_printf(m, "CQEs:\t%u\n", cq_tail - cq_head);
 165         cq_entries = min(cq_tail - cq_head, ctx->cq_entries);
 166         for (i = 0; i < cq_entries; i++) {
 167                 unsigned int entry = i + cq_head;
 168                 struct io_uring_cqe *cqe = &r->cqes[(entry & cq_mask) << cq_shift];
 169
 170                 seq_printf(m, "%5u: user_data:%llu, res:%d, flag:%x",
 171                            entry & cq_mask, cqe->user_data, cqe->res,
 172                            cqe->flags);
 173                 if (cq_shift)
 174                         seq_printf(m, ", extra1:%llu, extra2:%llu\n",
 175                                         cqe->big_cqe[0], cqe->big_cqe[1]);
 176                 seq_printf(m, "\n");
 177         }
 178
 179         /*
 180          * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
 181          * since fdinfo case grabs it in the opposite direction of normal use
 182          * cases. If we fail to get the lock, we just don't iterate any
 183          * structures that could be going away outside the io_uring mutex.
 184          */
 185         has_lock = mutex_trylock(&ctx->uring_lock);
 186
 187         if (has_lock && (ctx->flags & IORING_SETUP_SQPOLL)) {
 188                 struct io_sq_data *sq = ctx->sq_data;
 189
 190                 /*
 191                  * sq->thread might be NULL if we raced with the sqpoll
 192                  * thread termination.
 193                  */
 194                 if (sq->thread) {
 195                         sq_pid = sq->task_pid;
 196                         sq_cpu = sq->sq_cpu;
 197                         getrusage(sq->thread, RUSAGE_SELF, &sq_usage);
 198                         sq_total_time = (sq_usage.ru_stime.tv_sec * 1000000
 199                                          + sq_usage.ru_stime.tv_usec);
 200                         sq_work_time = sq->work_time;
 201                 }
 202         }
 203
 204         seq_printf(m, "SqThread:\t%d\n", sq_pid);
 205         seq_printf(m, "SqThreadCpu:\t%d\n", sq_cpu);
 206         seq_printf(m, "SqTotalTime:\t%llu\n", sq_total_time);
 207         seq_printf(m, "SqWorkTime:\t%llu\n", sq_work_time);
 208         seq_printf(m, "UserFiles:\t%u\n", ctx->file_table.data.nr);
 209         for (i = 0; has_lock && i < ctx->file_table.data.nr; i++) {
 210                 struct file *f = NULL;
 211
 212                 if (ctx->file_table.data.nodes[i])
 213                         f = io_slot_file(ctx->file_table.data.nodes[i]);
 214                 if (f)
 215                         seq_printf(m, "%5u: %s\n", i, file_dentry(f)->d_iname);
 216                 else
 217                         seq_printf(m, "%5u: <none>\n", i);
 218         }
 219         seq_printf(m, "UserBufs:\t%u\n", ctx->buf_table.nr);
 220         for (i = 0; has_lock && i < ctx->buf_table.nr; i++) {
 221                 struct io_mapped_ubuf *buf = NULL;
 222
 223                 if (ctx->buf_table.nodes[i])
 224                         buf = ctx->buf_table.nodes[i]->buf;
 225                 if (buf)
 226                         seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf, buf->len);
 227                 else
 228                         seq_printf(m, "%5u: <none>\n", i);
 229         }
 230         if (has_lock && !xa_empty(&ctx->personalities)) {
 231                 unsigned long index;
 232                 const struct cred *cred;
 233
 234                 seq_printf(m, "Personalities:\n");
 235                 xa_for_each(&ctx->personalities, index, cred)
 236                         io_uring_show_cred(m, index, cred);
 237         }
 238
 239         seq_puts(m, "PollList:\n");
 240         for (i = 0; has_lock && i < (1U << ctx->cancel_table.hash_bits); i++) {
 241                 struct io_hash_bucket *hb = &ctx->cancel_table.hbs[i];
 242                 struct io_kiocb *req;
 243
 244                 hlist_for_each_entry(req, &hb->list, hash_node)
 245                         seq_printf(m, "  op=%d, task_works=%d\n", req->opcode,
 246                                         task_work_pending(req->tctx->task));
 247         }
 248
 249         if (has_lock)
 250                 mutex_unlock(&ctx->uring_lock);
 251
 252         seq_puts(m, "CqOverflowList:\n");
 253         spin_lock(&ctx->completion_lock);
 254         list_for_each_entry(ocqe, &ctx->cq_overflow_list, list) {
 255                 struct io_uring_cqe *cqe = &ocqe->cqe;
 256
 257                 seq_printf(m, "  user_data=%llu, res=%d, flags=%x\n",
 258                            cqe->user_data, cqe->res, cqe->flags);
 259
 260         }
 261         spin_unlock(&ctx->completion_lock);
 262         napi_show_fdinfo(ctx, m);
 263 }
 264 #endif