From: Ruediger Meier <ruediger.meier@xxxxxxxxxxx>
Still no large integer support but on overflow we print now
the largest possible value, maybe even the largest one which
makes sense at all.
So on x86_64 systems we'll see now:
$ echo "4503599627370496" > /proc/sys/kernel/shmall
$ ipcs -m -l | grep "max total"
max total shared memory (kbytes) = 18014398509481980
rather than this:
$ ipcs -m -l | grep "max total"
max total shared memory (kbytes) = 0
Signed-off-by: Ruediger Meier <ruediger.meier@xxxxxxxxxxx>
---
sys-utils/ipcs.c | 10 ++++++++--
tests/ts/ipcs/functions.sh | 6 ++++++
tests/ts/ipcs/limits2 | 6 ------
3 files changed, 14 insertions(+), 8 deletions(-)
diff --git a/sys-utils/ipcs.c b/sys-utils/ipcs.c
index 4f3d23d..64f0aec 100644
--- a/sys-utils/ipcs.c
+++ b/sys-utils/ipcs.c
@@ -198,6 +198,7 @@ static void do_shm (char format, int unit)
case LIMITS:
{
struct ipc_limits lim;
+ uint64_t tmp, pgsz = getpagesize();
if (ipc_shm_get_limits(&lim)) {
printf (_("unable to fetch shared memory limits\n"));
@@ -207,9 +208,14 @@ static void do_shm (char format, int unit)
printf (_("max number of segments = %ju\n"), lim.shmmni);
ipc_print_size(unit == IPC_UNIT_DEFAULT ? IPC_UNIT_KB : unit,
_("max seg size"), lim.shmmax, "\n", 0);
+
+ tmp = (uint64_t) lim.shmall * pgsz;
+ /* overflow handling, at least we don't print ridiculus small values */
+ if (lim.shmall != 0 && tmp / lim.shmall != pgsz) {
+ tmp = UINT64_MAX - (UINT64_MAX % pgsz);
+ }
ipc_print_size(unit == IPC_UNIT_DEFAULT ? IPC_UNIT_KB : unit,
- _("max total shared memory"),
- (uint64_t) lim.shmall * getpagesize(), "\n", 0);
+ _("max total shared memory"), tmp, "\n", 0);
ipc_print_size(unit == IPC_UNIT_DEFAULT ? IPC_UNIT_BYTES : unit,
_("min seg size"), lim.shmmin, "\n", 0);
return;
diff --git a/tests/ts/ipcs/functions.sh b/tests/ts/ipcs/functions.sh
index a9cf228..586ce42 100644
--- a/tests/ts/ipcs/functions.sh
+++ b/tests/ts/ipcs/functions.sh
@@ -78,6 +78,12 @@ function ipcs_limits_check {
#echo "IPCS-CMD: ${IPCS_CMD[$i]}"
#echo
+ # overflow is handled differently because we don't have large
+ # int math, see https://github.com/karelzak/util-linux/issues/51
+ if [ $(bc <<<"$a >= 2^64/1024") -eq 1 ]; then
+ a=$(bc <<<"(2^64 - $PAGE_SIZE)/1024")
+ fi
+
if [ x"$a" == x"$b" ]; then
echo " OK"
else
diff --git a/tests/ts/ipcs/limits2 b/tests/ts/ipcs/limits2
index 4e96ce6..62a4f5b 100755
--- a/tests/ts/ipcs/limits2
+++ b/tests/ts/ipcs/limits2
@@ -27,12 +27,6 @@ ts_check_prog "bc"
. $TS_SELF/functions.sh
-# TODO https://github.com/karelzak/util-linux/issues/51
-SHMALL=$(</proc/sys/kernel/shmall)
-if [ $(bc <<<"(2^64 / $PAGE_SIZE) <= $SHMALL") -eq 1 ]; then
- TS_KNOWN_FAIL="yes"
-fi
-
ts_log "check for difference between kernel and IPC"
ipcs_limits_check >> $TS_OUTPUT
--
2.10.2
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