[PATCH v5 73/79] exec: cleanup qemu_minrampagesize()/qemu_maxrampagesize()

Igor Mammedov posted 79 patches 5 years, 11 months ago
Maintainers: "Michael S. Tsirkin" <mst@redhat.com>, KONRAD Frederic <frederic.konrad@adacore.com>, Jan Kiszka <jan.kiszka@web.de>, Paolo Bonzini <pbonzini@redhat.com>, Aurelien Jarno <aurelien@aurel32.net>, Cornelia Huck <cohuck@redhat.com>, Laurent Vivier <lvivier@redhat.com>, Paul Burton <pburton@wavecomp.com>, David Hildenbrand <david@redhat.com>, Radoslaw Biernacki <radoslaw.biernacki@linaro.org>, Fabien Chouteau <chouteau@adacore.com>, Andrew Baumann <Andrew.Baumann@microsoft.com>, Michael Walle <michael@walle.cc>, Peter Chubb <peter.chubb@nicta.com.au>, Richard Henderson <rth@twiddle.net>, Laurent Vivier <laurent@vivier.eu>, Aleksandar Rikalo <aleksandar.rikalo@rt-rk.com>, Sergio Lopez <slp@redhat.com>, Thomas Huth <huth@tuxfamily.org>, Beniamino Galvani <b.galvani@gmail.com>, Eduardo Habkost <ehabkost@redhat.com>, Jean-Christophe Dubois <jcd@tribudubois.net>, Helge Deller <deller@gmx.de>, Igor Mammedov <imammedo@redhat.com>, David Gibson <david@gibson.dropbear.id.au>, Andrew Jeffery <andrew@aj.id.au>, Joel Stanley <joel@jms.id.au>, Alistair Francis <alistair@alistair23.me>, Christian Borntraeger <borntraeger@de.ibm.com>, Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>, Thomas Huth <thuth@redhat.com>, "Hervé Poussineau" <hpoussin@reactos.org>, Andrey Smirnov <andrew.smirnov@gmail.com>, Halil Pasic <pasic@linux.ibm.com>, BALATON Zoltan <balaton@eik.bme.hu>, Antony Pavlov <antonynpavlov@gmail.com>, Aleksandar Markovic <amarkovic@wavecomp.com>, Rob Herring <robh@kernel.org>, Peter Maydell <peter.maydell@linaro.org>, "Cédric Le Goater" <clg@kaod.org>, "Philippe Mathieu-Daudé" <philmd@redhat.com>, Andrzej Zaborowski <balrogg@gmail.com>, Leif Lindholm <leif@nuviainc.com>, "Edgar E. Iglesias" <edgar.iglesias@gmail.com>, Marcel Apfelbaum <marcel.apfelbaum@gmail.com>, Artyom Tarasenko <atar4qemu@gmail.com>
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[PATCH v5 73/79] exec: cleanup qemu_minrampagesize()/qemu_maxrampagesize()
Posted by Igor Mammedov 5 years, 11 months ago
Since all RAM is backed by hostmem backends, drop
global -mem-path invariant and simplify code.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
---
v4:
  * fix access to uninitialized pagesize/hpsize
    (David Gibson <david@gibson.dropbear.id.au>)

CC: thuth@redhat.com
CC: aik@ozlabs.ru
CC: mdroth@linux.vnet.ibm.com
CC: david@gibson.dropbear.id.au
CC: qemu-ppc@nongnu.org
CC: pbonzini@redhat.com
CC: rth@twiddle.net
---
 exec.c | 49 ++++---------------------------------------------
 1 file changed, 4 insertions(+), 45 deletions(-)

diff --git a/exec.c b/exec.c
index 8e9cc3b47c..d85a8689d4 100644
--- a/exec.c
+++ b/exec.c
@@ -1667,59 +1667,18 @@ static int find_max_backend_pagesize(Object *obj, void *opaque)
 long qemu_minrampagesize(void)
 {
     long hpsize = LONG_MAX;
-    long mainrampagesize;
-    Object *memdev_root;
-    MachineState *ms = MACHINE(qdev_get_machine());
-
-    mainrampagesize = qemu_mempath_getpagesize(mem_path);
-
-    /* it's possible we have memory-backend objects with
-     * hugepage-backed RAM. these may get mapped into system
-     * address space via -numa parameters or memory hotplug
-     * hooks. we want to take these into account, but we
-     * also want to make sure these supported hugepage
-     * sizes are applicable across the entire range of memory
-     * we may boot from, so we take the min across all
-     * backends, and assume normal pages in cases where a
-     * backend isn't backed by hugepages.
-     */
-    memdev_root = object_resolve_path("/objects", NULL);
-    if (memdev_root) {
-        object_child_foreach(memdev_root, find_min_backend_pagesize, &hpsize);
-    }
-    if (hpsize == LONG_MAX) {
-        /* No additional memory regions found ==> Report main RAM page size */
-        return mainrampagesize;
-    }
-
-    /* If NUMA is disabled or the NUMA nodes are not backed with a
-     * memory-backend, then there is at least one node using "normal" RAM,
-     * so if its page size is smaller we have got to report that size instead.
-     */
-    if (hpsize > mainrampagesize &&
-        (ms->numa_state == NULL ||
-         ms->numa_state->num_nodes == 0 ||
-         ms->numa_state->nodes[0].node_memdev == NULL)) {
-        static bool warned;
-        if (!warned) {
-            error_report("Huge page support disabled (n/a for main memory).");
-            warned = true;
-        }
-        return mainrampagesize;
-    }
+    Object *memdev_root = object_resolve_path("/objects", NULL);
 
+    object_child_foreach(memdev_root, find_min_backend_pagesize, &hpsize);
     return hpsize;
 }
 
 long qemu_maxrampagesize(void)
 {
-    long pagesize = qemu_mempath_getpagesize(mem_path);
+    long pagesize = 0;
     Object *memdev_root = object_resolve_path("/objects", NULL);
 
-    if (memdev_root) {
-        object_child_foreach(memdev_root, find_max_backend_pagesize,
-                             &pagesize);
-    }
+    object_child_foreach(memdev_root, find_max_backend_pagesize, &pagesize);
     return pagesize;
 }
 #else
-- 
2.18.1


Re: [PATCH v5 73/79] exec: cleanup qemu_minrampagesize()/qemu_maxrampagesize()
Posted by Richard Henderson 5 years, 11 months ago
On 2/17/20 9:34 AM, Igor Mammedov wrote:
> Since all RAM is backed by hostmem backends, drop
> global -mem-path invariant and simplify code.
> 
> Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> ---
> v4:
>   * fix access to uninitialized pagesize/hpsize
>     (David Gibson <david@gibson.dropbear.id.au>)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>


r~