From: Sunil Dora Date: Tue, 17 Jun 2025 10:08:54 +0000 (-0700) Subject: glibc: nptl rename __condvar_quiesce_and_switch_g1 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e7eb16d59c81636c1fdffca307768776d990d732;p=thirdparty%2Fopenembedded%2Fopenembedded-core-contrib.git glibc: nptl rename __condvar_quiesce_and_switch_g1 The following commits have been cherry-picked from Glibc master branch: Bug : https://sourceware.org/bugzilla/show_bug.cgi?id=25847 Upstream-Status: Backport [https://sourceware.org/git/?p=glibc.git;a=commit;h=4b79e27a5073c02f6bff9aa8f4791230a0ab1867] Signed-off-by: Sunil Dora Signed-off-by: Steve Sakoman --- diff --git a/meta/recipes-core/glibc/glibc/0026-PR25847-7.patch b/meta/recipes-core/glibc/glibc/0026-PR25847-7.patch new file mode 100644 index 0000000000..a9e9cc7c48 --- /dev/null +++ b/meta/recipes-core/glibc/glibc/0026-PR25847-7.patch @@ -0,0 +1,160 @@ +From 2a601ac9041e2ca645acad2c174b1c545cfceafe Mon Sep 17 00:00:00 2001 +From: Malte Skarupke +Date: Tue, 17 Jun 2025 01:53:25 -0700 +Subject: [PATCH] nptl: rename __condvar_quiesce_and_switch_g1 + +This function no longer waits for threads to leave g1, so rename it to +__condvar_switch_g1 + +The following commits have been cherry-picked from Glibc master branch: +Bug : https://sourceware.org/bugzilla/show_bug.cgi?id=25847 + +Upstream-Status: Backport +[https://sourceware.org/git/?p=glibc.git;a=commit;h=4b79e27a5073c02f6bff9aa8f4791230a0ab1867] + +Signed-off-by: Sunil Dora +--- + nptl/pthread_cond_broadcast.c | 4 ++-- + nptl/pthread_cond_common.c | 26 ++++++++++++-------------- + nptl/pthread_cond_signal.c | 17 ++++++++--------- + nptl/pthread_cond_wait.c | 9 ++++----- + 4 files changed, 26 insertions(+), 30 deletions(-) + +diff --git a/nptl/pthread_cond_broadcast.c b/nptl/pthread_cond_broadcast.c +index 5ae141ac81..a07435589a 100644 +--- a/nptl/pthread_cond_broadcast.c ++++ b/nptl/pthread_cond_broadcast.c +@@ -60,7 +60,7 @@ ___pthread_cond_broadcast (pthread_cond_t *cond) + cond->__data.__g_size[g1] << 1); + cond->__data.__g_size[g1] = 0; + +- /* We need to wake G1 waiters before we quiesce G1 below. */ ++ /* We need to wake G1 waiters before we switch G1 below. */ + /* TODO Only set it if there are indeed futex waiters. We could + also try to move this out of the critical section in cases when + G2 is empty (and we don't need to quiesce). */ +@@ -69,7 +69,7 @@ ___pthread_cond_broadcast (pthread_cond_t *cond) + + /* G1 is complete. Step (2) is next unless there are no waiters in G2, in + which case we can stop. */ +- if (__condvar_quiesce_and_switch_g1 (cond, wseq, &g1, private)) ++ if (__condvar_switch_g1 (cond, wseq, &g1, private)) + { + /* Step (3): Send signals to all waiters in the old G2 / new G1. */ + atomic_fetch_add_relaxed (cond->__data.__g_signals + g1, +diff --git a/nptl/pthread_cond_common.c b/nptl/pthread_cond_common.c +index f976a533a1..3baac4dabc 100644 +--- a/nptl/pthread_cond_common.c ++++ b/nptl/pthread_cond_common.c +@@ -189,16 +189,15 @@ __condvar_get_private (int flags) + return FUTEX_SHARED; + } + +-/* This closes G1 (whose index is in G1INDEX), waits for all futex waiters to +- leave G1, converts G1 into a fresh G2, and then switches group roles so that +- the former G2 becomes the new G1 ending at the current __wseq value when we +- eventually make the switch (WSEQ is just an observation of __wseq by the +- signaler). ++/* This closes G1 (whose index is in G1INDEX), converts G1 into a fresh G2, ++ and then switches group roles so that the former G2 becomes the new G1 ++ ending at the current __wseq value when we eventually make the switch ++ (WSEQ is just an observation of __wseq by the signaler). + If G2 is empty, it will not switch groups because then it would create an + empty G1 which would require switching groups again on the next signal. + Returns false iff groups were not switched because G2 was empty. */ + static bool __attribute__ ((unused)) +-__condvar_quiesce_and_switch_g1 (pthread_cond_t *cond, uint64_t wseq, ++__condvar_switch_g1 (pthread_cond_t *cond, uint64_t wseq, + unsigned int *g1index, int private) + { + unsigned int g1 = *g1index; +@@ -214,8 +213,7 @@ __condvar_quiesce_and_switch_g1 (pthread_cond_t *cond, uint64_t wseq, + + cond->__data.__g_size[g1 ^ 1]) == 0) + return false; + +- /* Now try to close and quiesce G1. We have to consider the following kinds +- of waiters: ++ /* We have to consider the following kinds of waiters: + * Waiters from less recent groups than G1 are not affected because + nothing will change for them apart from __g1_start getting larger. + * New waiters arriving concurrently with the group switching will all go +@@ -223,12 +221,12 @@ __condvar_quiesce_and_switch_g1 (pthread_cond_t *cond, uint64_t wseq, + are not affected. + * Waiters in G1 have already received a signal and been woken. */ + +- /* Update __g1_start, which finishes closing this group. The value we add +- will never be negative because old_orig_size can only be zero when we +- switch groups the first time after a condvar was initialized, in which +- case G1 will be at index 1 and we will add a value of 1. +- Relaxed MO is fine because the change comes with no additional +- constraints that others would have to observe. */ ++ /* Update __g1_start, which closes this group. The value we add will never ++ be negative because old_orig_size can only be zero when we switch groups ++ the first time after a condvar was initialized, in which case G1 will be ++ at index 1 and we will add a value of 1. Relaxed MO is fine because the ++ change comes with no additional constraints that others would have to ++ observe. */ + __condvar_add_g1_start_relaxed (cond, + (old_orig_size << 1) + (g1 == 1 ? 1 : - 1)); + +diff --git a/nptl/pthread_cond_signal.c b/nptl/pthread_cond_signal.c +index 14800ba00b..a9bc10dcca 100644 +--- a/nptl/pthread_cond_signal.c ++++ b/nptl/pthread_cond_signal.c +@@ -69,18 +69,17 @@ ___pthread_cond_signal (pthread_cond_t *cond) + bool do_futex_wake = false; + + /* If G1 is still receiving signals, we put the signal there. If not, we +- check if G2 has waiters, and if so, quiesce and switch G1 to the former +- G2; if this results in a new G1 with waiters (G2 might have cancellations +- already, see __condvar_quiesce_and_switch_g1), we put the signal in the +- new G1. */ ++ check if G2 has waiters, and if so, switch G1 to the former G2; if this ++ results in a new G1 with waiters (G2 might have cancellations already, ++ see __condvar_switch_g1), we put the signal in the new G1. */ + if ((cond->__data.__g_size[g1] != 0) +- || __condvar_quiesce_and_switch_g1 (cond, wseq, &g1, private)) ++ || __condvar_switch_g1 (cond, wseq, &g1, private)) + { + /* Add a signal. Relaxed MO is fine because signaling does not need to +- establish a happens-before relation (see above). We do not mask the +- release-MO store when initializing a group in +- __condvar_quiesce_and_switch_g1 because we use an atomic +- read-modify-write and thus extend that store's release sequence. */ ++ establish a happens-before relation (see above). We do not mask the ++ release-MO store when initializing a group in __condvar_switch_g1 ++ because we use an atomic read-modify-write and thus extend that ++ store's release sequence. */ + atomic_fetch_add_relaxed (cond->__data.__g_signals + g1, 2); + cond->__data.__g_size[g1]--; + /* TODO Only set it if there are indeed futex waiters. */ +diff --git a/nptl/pthread_cond_wait.c b/nptl/pthread_cond_wait.c +index 104ebd48ca..bb46f3605d 100644 +--- a/nptl/pthread_cond_wait.c ++++ b/nptl/pthread_cond_wait.c +@@ -382,8 +382,7 @@ __pthread_cond_wait_common (pthread_cond_t *cond, pthread_mutex_t *mutex, + because we do not need to establish any happens-before relation with + signalers (see __pthread_cond_signal); modification order alone + establishes a total order of waiters/signals. We do need acquire MO +- to synchronize with group reinitialization in +- __condvar_quiesce_and_switch_g1. */ ++ to synchronize with group reinitialization in __condvar_switch_g1. */ + uint64_t wseq = __condvar_fetch_add_wseq_acquire (cond, 2); + /* Find our group's index. We always go into what was G2 when we acquired + our position. */ +@@ -414,9 +413,9 @@ __pthread_cond_wait_common (pthread_cond_t *cond, pthread_mutex_t *mutex, + { + /* Now wait until a signal is available in our group or it is closed. + Acquire MO so that if we observe (signals == lowseq) after group +- switching in __condvar_quiesce_and_switch_g1, we synchronize with that +- store and will see the prior update of __g1_start done while switching +- groups too. */ ++ switching in __condvar_switch_g1, we synchronize with that store and ++ will see the prior update of __g1_start done while switching groups ++ too. */ + unsigned int signals = atomic_load_acquire (cond->__data.__g_signals + g); + uint64_t g1_start = __condvar_load_g1_start_relaxed (cond); + unsigned int lowseq = (g1_start & 1) == g ? signals : g1_start & ~1U; +-- +2.49.0 + diff --git a/meta/recipes-core/glibc/glibc_2.35.bb b/meta/recipes-core/glibc/glibc_2.35.bb index d3c0cbd703..af122f00fb 100644 --- a/meta/recipes-core/glibc/glibc_2.35.bb +++ b/meta/recipes-core/glibc/glibc_2.35.bb @@ -68,6 +68,7 @@ SRC_URI = "${GLIBC_GIT_URI};branch=${SRCBRANCH};name=glibc \ file://0026-PR25847-4.patch \ file://0026-PR25847-5.patch \ file://0026-PR25847-6.patch \ + file://0026-PR25847-7.patch \ \ file://0001-Revert-Linux-Implement-a-useful-version-of-_startup_.patch \ file://0002-get_nscd_addresses-Fix-subscript-typos-BZ-29605.patch \