| Message ID | OF2BEB2003.14B7181E-ONC125862D.003F33FC-C125862D.003FF6BA@avm.de |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [v2] netstress: explicitly set a thread stack size | expand |
On 27.11.2020 14:38, Johannes Nixdorf via ltp wrote: > Musl libc uses a relatively small thread stack size (128k [1]). This > gets used up on 2 local buffers sized max_msg_len (64k by default), > which causes a segfault due to a stack overflow in the error reporting > path. > > Set the stack size to 256k instead, which is enough for both buffers > with an additional allowance for the remaining stack usage by netstress > and called libc or ltp helper functions. > > [1]: https://urldefense.com/v3/__https://wiki.musl-libc.org/functional-differences-from-glibc.html*Thread_stack_size__;Iw!!GqivPVa7Brio!Nat9ZPBR2P2QxOM2IsBWR2WdfOQ1ZNM4IJzjNy5a_bTsHUko9bULz88kJAVK8yQ7Kk8-$ > > Signed-off-by: Johannes Nixdorf <j.nixdorf@avm.de> > > --- > > v2: > - Use a static limit of 256k. > - Document the requested stack size in the error message. > - Coding style fixup. > Added extra parenthesis to silence possible compiler warnings and applied, thanks Johannes!
diff --git a/testcases/network/netstress/netstress.c b/testcases/network/netstress/netstress.c index e79e64220..48c0c23dc 100644 --- a/testcases/network/netstress/netstress.c +++ b/testcases/network/netstress/netstress.c @@ -480,7 +480,7 @@ static void client_init(void) clock_gettime(CLOCK_MONOTONIC_RAW, &tv_client_start); intptr_t i; for (i = 0; i < clients_num; ++i) - SAFE_PTHREAD_CREATE(&thread_ids[i], 0, client_fn, (void *)i); + SAFE_PTHREAD_CREATE(&thread_ids[i], &attr, client_fn, (void *)i); } static void client_run(void) @@ -747,8 +747,6 @@ static void server_run(void) struct sockaddr_in6 addr6; socklen_t addr_size = sizeof(addr6); - pthread_attr_init(&attr); - /* * detaching threads allow to reclaim thread's resources * once a thread finishes its work. @@ -980,6 +978,12 @@ static void setup(void) break; } + if (errno = pthread_attr_init(&attr)) + tst_brk(TBROK | TERRNO, "pthread_attr_init failed"); + + if (errno = pthread_attr_setstacksize(&attr, 256*1024)) + tst_brk(TBROK | TERRNO, "pthread_attr_setstacksize(256*1024) failed"); + net.init(); }
Musl libc uses a relatively small thread stack size (128k [1]). This gets used up on 2 local buffers sized max_msg_len (64k by default), which causes a segfault due to a stack overflow in the error reporting path. Set the stack size to 256k instead, which is enough for both buffers with an additional allowance for the remaining stack usage by netstress and called libc or ltp helper functions. [1]: https://wiki.musl-libc.org/functional-differences-from-glibc.html#Thread_stack_size Signed-off-by: Johannes Nixdorf <j.nixdorf@avm.de> --- v2: - Use a static limit of 256k. - Document the requested stack size in the error message. - Coding style fixup. testcases/network/netstress/netstress.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)