bpf: Add multi uprobe link#4990
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Adding new multi uprobe link that allows to attach bpf program
to multiple uprobes.
Uprobes to attach are specified via new link_create uprobe_multi
union:
struct {
__u32 flags;
__u32 cnt;
__aligned_u64 paths;
__aligned_u64 offsets;
__aligned_u64 ref_ctr_offsets;
} uprobe_multi;
Uprobes are defined in paths/offsets/ref_ctr_offsets arrays with
the same 'cnt' length. Each uprobe is defined with a single index
in all three arrays:
paths[idx], offsets[idx] and/or ref_ctr_offsets[idx]
The 'flags' supports single bit for now that marks the uprobe as
return probe.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Adding support to specify cookies array for uprobe_multi link. The cookies array share indexes and length with other uprobe_multi arrays (paths/offsets/ref_ctr_offsets). The cookies[i] value defines cookie for i-the uprobe and will be returned by bpf_get_attach_cookie helper when called from ebpf program hooked to that specific uprobe. Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Adding support for bpf_get_func_ip helper being called from ebpf program attached by uprobe_multi link. It returns the ip of the uprobe. Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Updating uapi bpf.h tools header with new uprobe_multi link interface. Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Adding new uprobe_multi attach type and link names, so the functions can resolve the new values. Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Currently we have elf_find_func_offset function that looks up
symbol in the binary and returns its offset to be used for uprobe
attachment.
For attaching multiple uprobes we will need interface that allows
us to get offsets for multiple symbols specified either by name or
regular expression.
Factoring out elf_for_each_symbol helper function that iterates
all symbols in binary and calls following callbacks:
fn_match - on each symbol
if it returns error < 0, we bail out with that error
fn_done - when we finish iterating symbol section,
if it returns true, we don't iterate next section
It will be used in following changes to lookup multiple symbols
and their offsets.
Changing elf_find_func_offset to use elf_for_each_symbol with
single_match callback that's looking to match single function.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Adding elf_find_multi_func_offset function that looks up offsets for symbols specified in syms array argument. Offsets are returned in allocated array with the 'cnt' size, that needs to be released by the caller. Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Adding elf_find_patern_func_offset function that looks up offsets for symbols specified by pattern argument. The 'pattern' argument allows wildcards (*?' supported). Offsets are returned in allocated array together with its size and needs to be released by the caller. Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Adding new uprobe_multi struct to bpf_link_create_opts object to pass multiple uprobe data to link_create attr uapi. Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Adding bpf_program__attach_uprobe_multi_opts function that
allows to attach multiple uprobes with uprobe_multi link.
The user can specify uprobes with direct arguments:
binary_path/func_pattern
or with struct bpf_uprobe_multi_opts opts argument fields:
const char **paths;
const char **syms;
const unsigned long *offsets;
const unsigned long *ref_ctr_offsets;
User can specify 3 mutually exclusive set of incputs:
1) use only binary_path/func_pattern aruments
2) use only opts argument with allowed combinations of:
paths/offsets/ref_ctr_offsets/cookies/cnt
3) use binary_path with allowed combinations of:
syms/offsets/ref_ctr_offsets/cookies/cnt
Any other usage results in error.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Adding support for uprobe.multi/uprobe.multi program sections to allow auto attach of multi_uprobe programs. Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Adding uprobe_multi bool to struct bpf_usdt_opts. If it's true the usdt_manager_attach_usdt will use uprobe_multi link to attach to usdt probes. The bpf program for usdt probe needs to have BPF_TRACE_UPROBE_MULTI set as expected_attach_type. Because current uprobe is implemented through perf event interface, it allows the pid filter for uprobes. This is not the case for uprobe_multi link, so the pid filter is not allowed for that. Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Adding uprobe_multi test for skeleton load/attach functions, to test skeleton auto attach for uprobe_multi link. Test that bpf_get_func_ip works properly for uprobe_multi attachment. Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Adding uprobe_multi test for bpf_program__attach_uprobe_multi_opts attach function. Testing attachment using glob patterns and via bpf_uprobe_multi_opts paths/syms fields. Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Adding uprobe_multi test for bpf_link_create attach function. Testing attachment using the struct bpf_link_create_opts. Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Adding uprobe_multi test program that defines 50k uprobe_multi_func_* functions and will serve as attach point for uprobe_multi bench test in following patch. Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Adding test that attaches 50k uprobes in uprobe_multi binary. After the attach is done we run the binary and make sure we get proper amount of hits. Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Adding usdt_multi test program that defines 50k usdts and will serve as attach point for uprobe_multi usdt bench test in following patch. Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Adding test that attaches 50k usdt probes in usdt_multi binary. After the attach is done we run the binary and make sure we get proper amount of hits. With current uprobes: # perf stat --null ./test_progs -n 254/6 #254/6 uprobe_multi_test/bench_usdt:OK #254 uprobe_multi_test:OK Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED Performance counter stats for './test_progs -n 254/6': 1353.659680562 seconds time elapsed With uprobe_multi link: # perf stat --null ./test_progs -n 254/6 #254/6 uprobe_multi_test/bench_usdt:OK #254 uprobe_multi_test:OK Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED Performance counter stats for './test_progs -n 254/6': 0.322046364 seconds time elapsed Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Adding test for cookies setup/retrieval in uprobe_link uprobes and making sure bpf_get_attach_cookie works properly. Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Author
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Upstream branch: 3515020 |
Author
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At least one diff in series https://patchwork.kernel.org/project/netdevbpf/list/?series=742796 expired. Closing PR. |
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Pull request for series with
subject: bpf: Add multi uprobe link
version: 1
url: https://patchwork.kernel.org/project/netdevbpf/list/?series=742796