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charset="UTF-8" X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 5A87740020 X-Rspam-User: X-Stat-Signature: m1fu5eueuhc9t8kfc5u44nnb9uumbm6z X-HE-Tag: 1675963020-430163 X-HE-Meta: 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 TRu+lvh/ a0nZD98j/cgmEgSHXpCEGQjQZYr4OHXmTAC/rt+uqQ3LZ5slqN1VrD+89PVkGZT75DF4Eg2nPdT8lr36V/YX/NjYNrvMsUScyreXpc/wNsfcAGX0QHmnltcPAd0CXntpT3bhTl4cAKsbVCQucKERR1WaKaQfBJrzQ1cOwONFHaz4zuC0a4Psm5OCaxX5FPCNeO2ZfFDeudMiMzky2QPFixn6y6x9aCBNd2deu3AitK22LN7CQJv0DHDBjBf0KOuD0NdB+lds3r6qf4QxstiXPixKI9TkDMtPEQSuh+JZkrOfCMcIU7uTfTUOIj1LAqr4M2oy06n9+gBpAUPV/gbFqIPqnqkjF7GXI0a6mA9AkkDiei413sRmgBYknhKvkfYa+pHwVblPkLTK9i7gHcLjPJcMX3yTWN+x3iM5JZ4LS+RVqQThY+0p1dRr42CJ1KIu3kKdXZszNH+QGVdXwmaC3ngHB52EbNJSIFIRkILWZgKpk3GuhaxFkclyOF3uyWtTAGb4jznPiCGimzlcKieYZv39kGyVPmtKz05NV X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Feb 9, 2023 at 6:04 AM Jiri Olsa wrote: > > On Wed, Feb 08, 2023 at 04:01:42PM -0800, Andrii Nakryiko wrote: > > SNIP > > > > +static void test_task_vma_buildid(void) > > > +{ > > > + int err, iter_fd = -1, proc_maps_fd = -1; > > > + struct bpf_iter_task_vma_buildid *skel; > > > + char key[D_PATH_BUF_SIZE], *prev_key; > > > + char bpf_build_id[BUILDID_STR_SIZE]; > > > + int len, files_fd, i, cnt = 0; > > > + struct build_id val; > > > + char *build_id; > > > + char c; > > > + > > > + skel = bpf_iter_task_vma_buildid__open(); > > > + if (!ASSERT_OK_PTR(skel, "bpf_iter_task_vma_buildid__open")) > > > + return; > > > + > > > + err = bpf_iter_task_vma_buildid__load(skel); > > > + if (!ASSERT_OK(err, "bpf_iter_task_vma_buildid__load")) > > > + goto out; > > > > minor: you can do __open_and_load() in one step > > right, I copied that from another test, but removed all the > setup in between, so we can actually call just __open_and_load > > SNIP > > > > + memset(bpf_build_id, 0x0, sizeof(bpf_build_id)); > > > + for (i = 0; i < val.sz; i++) { > > > + sprintf(bpf_build_id + i*2, "%02x", > > > + (unsigned char) val.data[i]); > > > + } > > > + > > > + if (!ASSERT_OK(read_buildid(key, &build_id), "read_buildid")) > > > + break; > > > + > > > + printf("BUILDID %s %s %s\n", bpf_build_id, build_id, key); > > > > debugging leftover or intentional? > > > > > + ASSERT_OK(strncmp(bpf_build_id, build_id, strlen(bpf_build_id)), "buildid_cmp"); > > > + > > > + free(build_id); > > > + prev_key = key; > > > + cnt++; > > > + } > > > + > > > + printf("checked %d files\n", cnt); > > > > ditto > > both intentional, first one can go out I guess, but the > number of checked files seemed interesting to me ;-) > > SNIP > > > > diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_task_vma_buildid.c b/tools/testing/selftests/bpf/progs/bpf_iter_task_vma_buildid.c > > > new file mode 100644 > > > index 000000000000..25e2179ae5f4 > > > --- /dev/null > > > +++ b/tools/testing/selftests/bpf/progs/bpf_iter_task_vma_buildid.c > > > @@ -0,0 +1,49 @@ > > > +// SPDX-License-Identifier: GPL-2.0 > > > + > > > +#include "bpf_iter.h" > > > +#include > > > +#include > > > + > > > +char _license[] SEC("license") = "GPL"; > > > + > > > +#define VM_EXEC 0x00000004 > > > +#define D_PATH_BUF_SIZE 1024 > > > + > > > +struct { > > > + __uint(type, BPF_MAP_TYPE_HASH); > > > + __uint(max_entries, 10000); > > > + __type(key, char[D_PATH_BUF_SIZE]); > > > + __type(value, struct build_id); > > > +} files SEC(".maps"); > > > + > > > +static char tmp_key[D_PATH_BUF_SIZE]; > > > +static struct build_id tmp_data; > > > + > > > +SEC("iter/task_vma") int proc_maps(struct bpf_iter__task_vma *ctx) > > > > nit: let's keep SEC() on separate line from function itself > > ok > > > > > > +{ > > > + struct vm_area_struct *vma = ctx->vma; > > > + struct seq_file *seq = ctx->meta->seq; > > > + struct task_struct *task = ctx->task; > > > + unsigned long file_key; > > > + struct file *file; > > > + > > > + if (task == (void *)0 || vma == (void *)0) > > > + return 0; > > > + > > > + if (!(vma->vm_flags & VM_EXEC)) > > > + return 0; > > > + > > > + file = vma->vm_file; > > > + if (!file) > > > + return 0; > > > + > > > + memset(tmp_key, 0x0, D_PATH_BUF_SIZE); > > > > __builtin_memset() to not rely on compiler optimization? > > > > > + bpf_d_path(&file->f_path, (char *) &tmp_key, D_PATH_BUF_SIZE); > > > + > > > + if (bpf_map_lookup_elem(&files, &tmp_key)) > > > + return 0; > > > + > > > + memcpy(&tmp_data, file->f_bid, sizeof(*file->f_bid)); > > > > same about __builtin_memcpy() > > ah ok, did not know that, will check.. curious what could > go wrong by using not '__builtin_...' version? if compiler doesn't optimize it into __builtin_memcpy() (which results in just explicit assembly code to copy/set data word-by-word), then BPF program will do actual call to memset(), which with C rules would be inferred as extern symbol, which would fail BPF object loading with error along the lines of "couldn't resolve memset extern". > > thanks, > jirka