Commit c83d628b authored by Alex Bennée's avatar Alex Bennée
Browse files

accel/tcg: better handle memory constrained systems 



It turns out there are some 64 bit systems that have relatively low
amounts of physical memory available to them (typically CI system).
Even with swapping available a 1GB translation buffer that fills up
can put the machine under increased memory pressure. Detect these low
memory situations and reduce tb_size appropriately.

Fixes: 600e17b2 ("accel/tcg: increase default code gen buffer size for 64 bit")
Signed-off-by: default avatarAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: default avatarRichard Henderson <richard.henderson@linaro.org>
Reviewed-by: default avatarRobert Foley <robert.foley@linaro.org>
Cc: BALATON Zoltan <balaton@eik.bme.hu>
Cc: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Message-Id: <20200724064509.331-7-alex.bennee@linaro.org>
parent 986babaa

accel/tcg/translate-all.c

+6 −1
Original line number Diff line number Diff line
@@ -976,7 +976,12 @@ static inline size_t size_code_gen_buffer(size_t tb_size) 
{

    /* Size the buffer.  */

    if (tb_size == 0) {

        size_t phys_mem = qemu_get_host_physmem();

        if (phys_mem == 0) {

            tb_size = DEFAULT_CODE_GEN_BUFFER_SIZE;

        } else {

            tb_size = MIN(DEFAULT_CODE_GEN_BUFFER_SIZE, phys_mem / 8);

        }

    }

    if (tb_size < MIN_CODE_GEN_BUFFER_SIZE) {

        tb_size = MIN_CODE_GEN_BUFFER_SIZE;