From: Sergey Senozhatsky Date: Mon, 2 Sep 2024 10:56:12 +0000 (+0900) Subject: zram: support priority parameter in recompression X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=e899007a5e10084649f558593f7e8f26088492fc;p=linux-2.6-block.git zram: support priority parameter in recompression recompress device attribute supports alg=NAME parameter so that we can specify only one particular algorithm we want to perform recompression with. However, with algo params we now can have several exactly same secondary algorithms but each with its own params tuning (e.g. priority 1 configured to use more aggressive level, and priority 2 configured to use a pre-trained dictionary). Support priority=NUM parameter so that we can correctly determine which secondary algorithm we want to use. Link: https://lkml.kernel.org/r/20240902105656.1383858-25-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky Cc: Minchan Kim Cc: Nick Terrell Signed-off-by: Andrew Morton --- diff --git a/Documentation/admin-guide/blockdev/zram.rst b/Documentation/admin-guide/blockdev/zram.rst index d3b676273528..678d70d6e1c3 100644 --- a/Documentation/admin-guide/blockdev/zram.rst +++ b/Documentation/admin-guide/blockdev/zram.rst @@ -512,11 +512,14 @@ registered compression algorithms, increases our chances of finding the algorithm that successfully compresses a particular page. Sometimes, however, it is convenient (and sometimes even necessary) to limit recompression to only one particular algorithm so that it will not try any other algorithms. -This can be achieved by providing a algo=NAME parameter::: +This can be achieved by providing a `algo` or `priority` parameter::: #use zstd algorithm only (if registered) echo "type=huge algo=zstd" > /sys/block/zramX/recompress + #use zstd algorithm only (if zstd was registered under priority 1) + echo "type=huge priority=1" > /sys/block/zramX/recompress + memory tracking =============== diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index 9b29f9e6cb50..1f1bf175a6c3 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -1855,6 +1855,18 @@ static ssize_t recompress_store(struct device *dev, algo = val; continue; } + + if (!strcmp(param, "priority")) { + ret = kstrtouint(val, 10, &prio); + if (ret) + return ret; + + if (prio == ZRAM_PRIMARY_COMP) + prio = ZRAM_SECONDARY_COMP; + + prio_max = min(prio + 1, ZRAM_MAX_COMPS); + continue; + } } if (threshold >= huge_class_size)