Re: [Crash-utility] Problem with "timer" command on RHEL7.6

On 8/1/2019 2:31 PM, Kazuhito Hagio wrote: > On 8/1/2019 1:22 PM, Dave Anderson wrote: >> >> >> ----- Original Message ----- >>> Hi Dave, >>> >>> I noticed that the "timer" command prints somewhat wrongly for RHEL7.6 or >>> later kernels (not including RHEL8 / upstream) and found that it is >>> because >>> struct tvec and tvec_root have an array of list_head, instead of >>> hlist_head >>> in upstream kernels. >>> >>> So the following patch looks good only for RHEL7, but I don't know how we >>> should determine the list type in order to switch the size, etc in this case. >>> What do you think? >> >> Try using the MEMBER_TYPE_NAME() macro. For example, adding this to >> cmd_test(): > > Nice. I'll try to rewrite the patch with it. I choose to add head_size arg to do_timer_list_v3(). This tested OK on RHEL7.6 and kernel 4.2.1.

Signed-off-by: Kazuhito Hagio <k-hagio(a)ab.jp.nec.com&gt; --- diff --git a/kernel.c b/kernel.c index a79e5a3010ea..7804aef2074b 100644 --- a/kernel.c +++ b/kernel.c @@ -53,7 +53,7 @@ static void dump_timer_data_timer_bases(const ulong *cpus); struct tv_range; static void init_tv_ranges(struct tv_range *, int, int, int); static int do_timer_list(ulong,int, ulong *, void *,ulong *, ulong *, struct tv_range *, ulong); -static int do_timer_list_v3(ulong, int, ulong *, void *,ulong *, ulong *, ulong); +static int do_timer_list_v3(ulong, int, ulong *, void *,ulong *, ulong *, ulong, long); struct timer_bases_data; static int do_timer_list_v4(struct timer_bases_data *, ulong); static int compare_timer_data(const void *, const void *); @@ -8376,7 +8376,12 @@ dump_timer_data_tvec_bases_v3(const ulong *cpus) char buf4[BUFSIZE]; vec_root_size = vec_size = 0; - head_size = SIZE(hlist_head); + + if (STREQ(MEMBER_TYPE_NAME("tvec_root", "vec"), "list_head")) + /* for RHEL7.6 or later */ + head_size = SIZE(list_head); + else + head_size = SIZE(hlist_head); if ((i = get_array_length("tvec_root.vec", NULL, head_size))) vec_root_size = i; @@ -8414,15 +8419,15 @@ next_cpu: init_tv_ranges(tv, vec_root_size, vec_size, cpu); count += do_timer_list_v3(tv[1].base + OFFSET(tvec_root_s_vec), - vec_root_size, vec, NULL, NULL, NULL, 0); + vec_root_size, vec, NULL, NULL, NULL, 0, head_size); count += do_timer_list_v3(tv[2].base + OFFSET(tvec_s_vec), - vec_size, vec, NULL, NULL, NULL, 0); + vec_size, vec, NULL, NULL, NULL, 0, head_size); count += do_timer_list_v3(tv[3].base + OFFSET(tvec_s_vec), - vec_size, vec, NULL, NULL, NULL, 0); + vec_size, vec, NULL, NULL, NULL, 0, head_size); count += do_timer_list_v3(tv[4].base + OFFSET(tvec_s_vec), - vec_size, vec, NULL, NULL, NULL, 0); + vec_size, vec, NULL, NULL, NULL, 0, head_size); count += do_timer_list_v3(tv[5].base + OFFSET(tvec_s_vec), - vec_size, vec, NULL, NULL, NULL, 0); + vec_size, vec, NULL, NULL, NULL, 0, head_size); if (count) td = (struct timer_data *) @@ -8433,16 +8438,16 @@ next_cpu: get_symbol_data("jiffies", sizeof(ulong), &jiffies); - do_timer_list_v3(tv[1].base + OFFSET(tvec_root_s_vec), - vec_root_size, vec, (void *)td, &highest, &highest_tte, jiffies); - do_timer_list_v3(tv[2].base + OFFSET(tvec_s_vec), - vec_size, vec, (void *)td, &highest, &highest_tte, jiffies); - do_timer_list_v3(tv[3].base + OFFSET(tvec_s_vec), - vec_size, vec, (void *)td, &highest, &highest_tte, jiffies); - do_timer_list_v3(tv[4].base + OFFSET(tvec_s_vec), - vec_size, vec, (void *)td, &highest, &highest_tte, jiffies); - tdx = do_timer_list_v3(tv[5].base + OFFSET(tvec_s_vec), - vec_size, vec, (void *)td, &highest, &highest_tte, jiffies); + do_timer_list_v3(tv[1].base + OFFSET(tvec_root_s_vec), vec_root_size, + vec, (void *)td, &highest, &highest_tte, jiffies, head_size); + do_timer_list_v3(tv[2].base + OFFSET(tvec_s_vec), vec_size, + vec, (void *)td, &highest, &highest_tte, jiffies, head_size); + do_timer_list_v3(tv[3].base + OFFSET(tvec_s_vec), vec_size, + vec, (void *)td, &highest, &highest_tte, jiffies, head_size); + do_timer_list_v3(tv[4].base + OFFSET(tvec_s_vec), vec_size, + vec, (void *)td, &highest, &highest_tte, jiffies, head_size); + tdx = do_timer_list_v3(tv[5].base + OFFSET(tvec_s_vec), vec_size, + vec, (void *)td, &highest, &highest_tte, jiffies, head_size); qsort(td, tdx, sizeof(struct timer_data), compare_timer_data); @@ -8786,7 +8791,8 @@ do_timer_list_v3(ulong vec_kvaddr, void *option, ulong *highest, ulong *highest_tte, - ulong jiffies) + ulong jiffies, + long head_size) { int i, t; int count, tdx; @@ -8804,19 +8810,24 @@ do_timer_list_v3(ulong vec_kvaddr, tdx++; } - readmem(vec_kvaddr, KVADDR, vec, SIZE(hlist_head) * size, + readmem(vec_kvaddr, KVADDR, vec, head_size * size, "timer_list vec array", FAULT_ON_ERROR); ld = &list_data; timer_list_buf = GETBUF(SIZE(timer_list)); - for (i = count = 0; i < size; i++, vec_kvaddr += SIZE(hlist_head)) { + for (i = count = 0; i < size; i++, vec_kvaddr += head_size) { - if (vec[i] == 0) - continue; + if (head_size == SIZE(list_head)) { + if (vec[i*2] == vec_kvaddr) + continue; + } else { + if (vec[i] == 0) + continue; + } BZERO(ld, sizeof(struct list_data)); - ld->start = vec[i]; + ld->start = (head_size == SIZE(list_head)) ? vec[i*2] : vec[i]; ld->list_head_offset = OFFSET(timer_list_entry); ld->end = vec_kvaddr; ld->flags = RETURN_ON_LIST_ERROR;